| 1. |
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| 2. |
- Risseh, Arash, 1980-, et al.
(författare)
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Design of a Thermoelectric Generator for Waste Heat Recovery Application on a Drivable Heavy Duty Vehicle
- 2017
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Ingår i: SAE International Journal of Commercial Vehicles. - : SAE International. - 1946-391X .- 1946-3928. ; 10:1, s. 26-44
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Tidskriftsartikel (refereegranskat)abstract
- The European Union’s 2020 target aims to be producing 20 % of its energy from renewable sources by 2020, to achieve a 20 % reduction in greenhouse gas emissions and a 20 % improvement in energy efficiency compared to 1990 levels. To reach these goals, the energy consumption has to decrease which results in reduction of the emissions. The transport sector is the second largest energy consumer in the EU, responsible for 25 % of the emissions of greenhouse gases caused by the low efficiency (<40 %) of combustion engines. Much work has been done to improve that efficiency but there is still a large amount of fuel energy that converts to heat and escapes to the ambient atmosphere through the exhaust system. Taking advantage of thermoelectricity, the heat can be recovered, improving the fuel economy. A thermoelectric generator (TEG) consists of a number of thermoelectric elements, which advantageously can be built into modules, arranged thermally and electrically, in a way such that the highest possible thermal power can be converted into electrical power. In a unique waste heat recovery (WHR) project, five international companies and research institutes cooperated and equipped a fully drivable Scania prototype truck with two TEGs. The entire system, from the heat transfer in the exchangers to the electrical power system, was simulated, built and evaluated. The primary experimental results showed that approximately 1 kW electrical power could be generated from the heat energy. In this paper the entire system from design to experimental results is presented.
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| 3. |
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| 4. |
- Thelin, Peter, et al.
(författare)
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Analytical Calculation of the Airgap Flux Density of PM Synchronous Motors with Buried Magnets Including Axial Leakage, Tooth and Yoke Saturations
- 2000
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Ingår i: Proc. of the International Conference on Power Electronics and Variable Speed Drives, London, September 2000.. - : IEE. ; , s. 218-223
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Konferensbidrag (refereegranskat)abstract
- It has been shown earlier that the airgap flux density of PM motors with buried magnets can be calculated with a satisfactory result, if saturated iron bridges, axial leakage flux (from 2D-FEM) and teeth saturation are taken into account. In this paper, instead of using 2D-FEM, an analytical expression for the axial reluctance is derived. By including the saturation of rotor and stator yokes, the model is even further improved. The result is a complete analytical model, which takes into account all phenomena mentioned above, and improves the agreement with experimental values.
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| 5. |
- Thelin, Peter, et al.
(författare)
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Calculation of the Airgap Flux Density of PM Synchronous Motors with Buried Magnets including Axial Leakage and Teeth Saturation
- 1999
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Ingår i: Proc. of the Electrical Machines and Drives Conference, Canterbury, UK, September 1999. - : Institution of Electrical Engineers (IEE). ; , s. 339-345
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Konferensbidrag (refereegranskat)abstract
- It has been shown earlier that the airgap flux density of unsaturated PM motors with buried magnets can be calculated analytically, with a satisfactory result, compared to 2D-FEM calculations. By taking axial leakage flux, and stator and rotor teeth saturation into account an improved expression for the airgap flux density, showing better agreement with experiments, is obtained.
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| 6. |
- Thelin, Peter, et al.
(författare)
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Comparison between Different Ways to Calculate the Induced No-Load Voltage of PM Synchronous Motors using Finite Element Methods
- 2001
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Ingår i: Proc. of the 4th IEEE International Conference on Power Electronics and Drive Systems (PEDS'01), Bali, Indonesia, October 2001, vol. 2.. ; , s. 468-474
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Konferensbidrag (refereegranskat)abstract
- In this paper two different ways of calculating the induced no-load voltage of permanent magnet synchronous motors (PMSM), by the use of a finite element method (FEM) program, have been compared. Neither of the two calculation methods require a FEM software package that can perform time-stepping. The number of required static FEM-calculations is limited to just a few, or even to one. The calculations are performed on five motor geometries. The results are compared to values obtained from time-stepping FEM-calculations, and to the measured induced no-load voltages of the five manufactured prototype motors. It can be seen that the least time-consuming method is accurate enough in most of these cases. The exceptions, in this study, are when there are relatively large airgaps and/or when the stator teeth are saturated.
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| 7. |
- Thelin, Peter, et al.
(författare)
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Development and Efficiency Measurements of a Compact 15 kW 1500 r/min Integral Permanent Magnet Synchronous Motor
- 2000
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Ingår i: Proc. of the IEEE Industry Applications Society Annual Meeting, Roma, Italy, October 2000.. ; , s. 155-162
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Konferensbidrag (refereegranskat)abstract
- This paper presents the development of a 15 kW, 1500 r/min integral motor, with the same outer dimensions as an equivalent standard induction motor, but with the possibility of operating with speed control and at a higher efficiency. To make a compact integral motor, a permanent magnet rotor is used, the coils of the line-filter and the coil of the DC-link have been integrated with the stator core, only a small DC-link capacitor is employed, and the motor is controlled without a shaft sensor. Temperature and efficiency measurements on the manufactured prototype machine are performed and the results are very promising.
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| 8. |
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| 9. |
- Thelin, Peter, et al.
(författare)
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Rotor Cage Losses of an Inverter-Fed PMSM investigated with FEM
- 2003
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Ingår i: Proceedings of the European Conference on Power Electronics and Applications, EPE´03.
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Konferensbidrag (refereegranskat)abstract
- In the design of a compact inverter-fed buried permanent magnet synchronous motor, the high-frequency losses of the sparse rotor cage - which are difficult to predict - were assumed to be small. To investigate these ohmic high-frequency losses of the rotor cage, fixed-speed time-stepping 2D-FEM calculations have been carried out. The losses due to only the magnets, magnets and sinusoidal currents, high-frequency currents etc., and the actual currents are presented. The actual current wave-forms were obtained from measurements on the manufactured prototype motor.
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| 10. |
- Thelin, Peter, et al.
(författare)
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Suggestions Regarding the Pole-Number of Inverter-Fed PM-Synchronous Motors with Buried Magnets
- 1998
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Ingår i: Proc. of the International Conference on Power Electronics and Variable Speed Drives 1998. - : Institution of Electrical Engineers (IEE). ; , s. 544-547
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Konferensbidrag (refereegranskat)abstract
- When designing an inverter-fed PM-motor, one is quite free to choose a number of poles which utilizes the machine in a good way. A common rule of thumb is to choose a high pole-number for low-speed motors and vice versa, but there are no sharp borderlines between the different areas. This paper gives a suggestion regarding the pole-number for a desired power and speed of the motor.
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| 11. |
- Zhang, Yafan, et al.
(författare)
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Thermal evaluation of a liquid/air cooled integrated power inverter for hybrid vehicle applications
- 2013
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Ingår i: 2013 14th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems, EuroSimE 2013. - New York : IEEE. - 9781467361385 - 9781467361378 ; , s. 6529944-
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Konferensbidrag (refereegranskat)abstract
- A thermal design of an integrated double-side cooled SiC 50kW-1200V-200A power inverter for hybrid electric vehicle applications has been proposed to enable cooling in two different automotive operating environments: under-hood and controlled temperature environment of passenger compartment. The power inverter is integrated with air/liquid cooled cold plates equipped with finned channels. Concept evaluation and CFD model calibration have been performed on a simplified thermal prototype. Computational experiments on the detailed model of the inverter, including packaging materials, have been performed for automotive industry defined application scenarios, including two extreme and one typical driving cycles. For the studied application scenarios the case temperature of the SiC transistors and diodes have been found to be below 210°C. The maximum steady-state temperature of the DC-link capacitor has been below 127 °C for the worst-case scenario including liquid cooling, and up to 140 °C for the worst-case scenario with air-cooling.
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| 12. |
- Abbas, Khizra, et al.
(författare)
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Autonomous Gate Drivers Tailored for Triangular Current Mode-Based Zero-Voltage Switching Two-Level Three-Phase Inverters for Electric Vehicle Drive Systems
- 2024
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Ingår i: Energies. - : MDPI AG. - 1996-1073. ; 17:5
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Tidskriftsartikel (refereegranskat)abstract
- The demand for highly efficient and dynamic electric vehicles (EVs) has increased dramatically. The traction inverter, a pivotal component in an EV powertrain, plays a crucial role. This study is dedicated to designing a traction inverter with focus on achieving high efficiency and elevated power density and mitigating electromagnetic interference (EMI) issues. To realize these objectives, autonomous gate drivers (AGDs) are proposed and designed using LTspice simulation software. The aim is to achieve zero voltage switching (ZVS) at both turn-on and turn-off through the utilization of triangular current mode (TCM) control on the gate driver. The AGDs implement a current modulation scheme by sensing the current and voltage and generating gate-source voltage signals with minimal delays. The implemented current modulation scheme by the AGDs results in an efficiency exceeding 99% for a 10 kW power rating. The sinusoidal output waveforms not only contribute to extending the motor lifespan by mitigating sharp-edge voltages but also bring advantages such as reduced switch stress, decreased EMI, and simplified thermal management.
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| 13. |
- Abbas, Khizra, et al.
(författare)
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Autonomously Modulating Gate Drivers For Triangular-Current Mode (TCM) Zero-Voltage Switching (ZVS) Buck Converter
- 2023
-
Ingår i: Proceedings of 22nd International Symposium on Power Electronics, Ee 2023. - : Institute of Electrical and Electronics Engineers (IEEE).
-
Konferensbidrag (refereegranskat)abstract
- This paper introduces a novel approach to designing autonomous gate drivers for soft-switched buck converters. The objective is to reduce switching losses, enhance converter efficiency, and reduce electromagnetic interference (EMI). The uniqueness of this converter is that the pulse-width modulation is performed autonomously on the gate driver. The gate driver makes quick decisions on switching times, capitalizing on the minimal time delay between measurements and switching. In the proposed buck converter configuration, the gate driver senses both the current and voltage across the switches to avoid delay. When a slightly negative voltage is detected across the switch, it rapidly turns on, resulting in a zero-voltage switching (ZVS). With an external snubber capacitor placed across the switches, the turn-off switching losses are zero (ZVS). Hence, both the turn-on and turn-off of the switch are soft. To enable the switch to turn off, a reference value of the switch current needs to be sent out to the gate driver using a galvanically isolated current sensor. Through this approach, the efficiency of the 7 kW buck converter has been calculated to exceed 99% without including the filter losses. Additional benefits include reduced switch stresses, diminished electromagnetic interference (EMI), and simplified thermal management.
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| 14. |
- Abbas, Khizra, et al.
(författare)
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Comprehensive Insight into the Operational Dynamics of TCM-Based Zero-Voltage Switching (ZVS) Two-Level Three-Phase Inverters for Electric Vehicle (EV) Motor-Drive Applications
- 2024
-
Ingår i: 2024 IEEE Texas Power and Energy Conference, TPEC 2024. - : Institute of Electrical and Electronics Engineers (IEEE).
-
Konferensbidrag (refereegranskat)abstract
- This paper introduces a novel triangular-current mode (TCM), zero-voltage switching (ZVS) two-level three-phase inverter, specifically designed to enhance the performance of the electric vehicle (EV) drive system. The primary objective is to enhance the inverter efficiency by minimizing turn-on and turn-off switching losses while mitigating electromagnetic interference (EMI) by generating sinusoidal output waveforms. The distinctive feature of this inverter lies in its gate driver, which executes the current modulation scheme. Achieving ZVS during turn-on involves the gate driver sensing the switch voltage and turning it on at zero voltage, utilizing TCM. For turn-off ZVS, the gate driver monitors the switch current, turning it off when it exceeds a predefined reference value. With a carefully placed snubber capacitor, turn-off ZVS is achieved. The implemented current modulation scheme yields an efficiency exceeding 99% for a 10 kW power rating. The sinusoidal output waveforms not only enhance motor lifespan by safeguarding against sharp-edge voltages but also offer benefits like reduced switch stress and simplified thermal management.
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| 15. |
- Abdelhakim, A., et al.
(författare)
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Single-Stage Boost Modular Multilevel Converter (BMMC) for Energy Storage Interface
- 2020
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Ingår i: 2020 22nd European Conference on Power Electronics and Applications, EPE 2020 ECCE Europe. - : Institute of Electrical and Electronics Engineers (IEEE).
-
Konferensbidrag (refereegranskat)abstract
- Single-stage DC-AC power converters are gaining higher attention due to their simpler structure compared to the two-stage equivalent solution. In this paper, a single-stage DC-AC converter solution is proposed for interfacing a low voltage (LV) DC source with a higher voltage AC load or grid, where this converter has a modular structure with multilevel operation. The proposed converter, which is called boost modular multilevel converter (BMMC), comprises the boosting capability within the inversion operation, and it is mainly dedicated for interfacing LV energy storage systems, such as fuel cells and batteries, and it allows the use of LV MOSFETs (« 300 V), in order to utilize their low ON-state resistance, along with LV electrolytic capacitors. This converter is introduced and analysed in this paper, where simulation results using PLECS, considering a 10 kW three-phase BMMC, are presented in order to verify its functionality.
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| 16. |
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| 17. |
- Ahmed, Noman, et al.
(författare)
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HVDC SuperGrids with modular multilevel converters - The power transmission backbone of the future
- 2012
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Ingår i: International Multi-Conference on Systems, Signals and Devices, SSD 2012. - : IEEE. - 9781467315906 ; , s. 6198119-
-
Konferensbidrag (refereegranskat)abstract
- In order to transmit massive amounts of power generated by remotely located power plants, especially offshore wind farms, and to balance the intermittent nature of renewable energy sources, the need for a stronger high voltage transmission grid is anticipated. Due to limitations in ac power transmission the most likable choice for such a grid is a high-voltage dc (HVDC) grid. However, the concept of the HVDC grid is still under active development as different technical challenges exist, and it is not yet possible to construct such a dc grid. This paper deals with prospects and technical challenges for future HVDC SuperGrids. Different topologies for a SuperGrid and the possibility to use modular multilevel converters (M2Cs) are presented. A comprehensive overview of different submodule implementations of M2C is given as well as a discussion on the choice between cables or overhead lines, the protection system for the dc grid and dc-side resonance issues.
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| 18. |
- Ahmed, Noman, et al.
(författare)
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Performance of the modular multilevel converter with redundant submodules
- 2015
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Ingår i: IECON 2015 - 41st Annual Conference of the IEEE Industrial Electronics Society. - : Institute of Electrical and Electronics Engineers (IEEE). - 9781479917624 ; , s. 3922-3927
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Konferensbidrag (refereegranskat)abstract
- The modular multilevel converter (MMC) is the state-of-the-art voltage-source converter (VSC) topology used for various power-conversion applications. In the MMC, submodule failures can occur due to various reasons. Therefore, additional submodules called the redundant submodules are included in the arms of the MMC to fulfill the fault-safe operation requirement. The performance of the MMC with redundant submodules has not been widely covered in the published literature. This paper investigates the performance of the MMC with redundant submodules in the arms. Two different control strategies are used and compared for integrating redundant submodules. The response of the MMC to a submodule failure for the two strategies is also studied. Moreover, the operation of the MMC with redundant submodules is validated experimentally using the converter prototype in the laboratory.
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| 19. |
- Ahmed, Noman, et al.
(författare)
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Prospects and challenges of future HVDC SuperGrids with modular multilevel converters
- 2011
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Ingår i: Proceedings of the 2011-14th European Conference on Power Electronics and Applications (EPE 2011). - 9781612841670 - 9789075815153
-
Konferensbidrag (refereegranskat)abstract
- In order to transmit massive amounts of power generated by remotely located power plants, especially offshore wind farms, and to balance the intermittent nature of renewable energy sources, the need for a stronger high voltage transmission grid is anticipated. Due to limitations in AC power transmission the most likable choice for such a grid is a high voltage DC (HVDC) grid. However, the concept of the HVDC grid is still under active development as different technical challenges exist, and it is not yet possible to construct such a DC grid. This paper deals with prospects and technical challenges for the future HVDC SuperGrids. Different topologies for a SuperGrid and the possibility to use modular multilevel converters (M2Cs) are presented. A comprehensive overview of different sub-module implementations of M2C is given. An overview of short circuit behaviour of the M2C is also given, as well as a discussion on the choice between cables or overhead lines and DC-side resonance issues.
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| 20. |
- Anpalahan, Peethamparam, et al.
(författare)
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Design Steps towards a High Power Factor Transverse Flux Machine
- 2001
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Ingår i: Proc. of the European Conference on Power Electronics and Applications (EPE), Graz, Austria, August 2001.
-
Konferensbidrag (refereegranskat)abstract
- This article describes a topology of three-phase transverse flux machine and the derivation of ananalytical model which does not exist in the literature. Three dimensional finite element analysis isalso used to get more accurate results. Steps carried out to obtain a better power factor are presented.
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| 21. |
- Asoodar, Mohsen, et al.
(författare)
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A Computationally Efficient Model for Large-Scale Energy Storage Systems With Active Voltage Balancing in Modular Multilevel Converters
- 2023
-
Ingår i: 2023 IEEE Applied Power Electronics Conference And Exposition, APEC. - : Institute of Electrical and Electronics Engineers (IEEE). ; , s. 2973-2978
-
Konferensbidrag (refereegranskat)abstract
- In this paper, a novel method for modeling and simulation of large-scale energy storage systems (ESS) is provided. Specifically, the model is developed for large-scale series connected supercapacitors (SCs) intended for power electronic applications. This method is especially useful for high voltage applications where a large number of series connected energy storage units (ESUs) are required. The proposed solution reduces a multi-node string of series connected SCs-together with their corresponding voltage balancing circuit-to a single unit with two electrical nodes. The proposed model is connected to the dc link of a three phase grid-connected modular multilevel converter (MMC). In this system, the effectiveness of the proposed model and the proposed voltage balancing scheme is demonstrated for a string comprising ten thousand series connected ESUs. The efficacy of the proposed model and the balancing algorithm is proven by simulations in the MATLAB/Simulink environment.
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| 22. |
- Asoodar, Mohsen, et al.
(författare)
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A Condition Monitoring Scheme for Semiconductor Devices in Modular Multilevel Converters with Cascaded H-Bridge Submodules
- 2022
-
Ingår i: 24th European Conference on Power Electronics and Applications, EPE 2022 ECCE Europe. - : Institute of Electrical and Electronics Engineers Inc..
-
Konferensbidrag (refereegranskat)abstract
- In this paper, a novel online semiconductor device monitoring scheme is presented. The condition monitoring (CM) scheme is based on measuring the ON-state voltage drop of semiconductor devices, and tracking the changes in their ON-state resistance. The proposed solution measures the ON-state voltage of semiconductor devices at a controlled and readily measurable temperature. This allows for accurate CM of semiconductors as it decouples temperature related and degradation related changes in the ON-state voltage. The temperature decoupling is achieved using natural switching redundancies available to modular multilevel converter systems. Hence, the proposed CM scheme does not interfere with the output voltages and currents generated by the converter.
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| 23. |
- Asoodar, Mohsen, et al.
(författare)
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A Measurement-Based Method for Characterizing Parasitic Inductances in Power Electronic Circuits
- 2021
-
Ingår i: 2021 23rd European Conference on Power Electronics and Applications, EPE 2021 ECCE Europe.
-
Konferensbidrag (refereegranskat)abstract
- This paper presents a new method of measuring parasitic inductances in various elements of power electronic circuits. The proposed solution features a low-cost design while providing accurate measurement results in a predefined range of stray inductances. The solution utilizes a unique parallel resonance circuit for extracting stray inductances in various circuits. Structural challenges as well as the analysis for the choice of circuit parameters are addressed in this study. Both simulation and experimental results are presented to exhibit the efficacy of the solution. Moreover, important design constraints that can affect the end results are explained and considered in the proposed experimental setup.
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| 24. |
- Asoodar, Mohsen, et al.
(författare)
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A Novel ON-State Resistance Estimation Technique for Online Condition Monitoring of Semiconductor Devices Under Noisy Conditions
- 2024
-
Ingår i: IEEE Open Journal of Instrumentation and Measurement. - : Institute of Electrical and Electronics Engineers (IEEE). - 2768-7236. ; 3
-
Tidskriftsartikel (refereegranskat)abstract
- This article presents a novel method for accurate online extraction of semiconductor ON-state resistance in the presence of measurement noise. In this method, the ON-state resistance value is extracted from the measured ON-state voltage of the semiconductors and the measured load current. The extracted ON-state resistance can be used for online condition monitoring of semiconductors. The proposed method is based on the extraction of selective harmonic content. The estimated values are further enhanced through an integral action that increases the signal-to-noise ratio, making the proposed method suitable in the presence of noisy measurements. The efficacy of the proposed method is verified through simulations in the MATLAB/Simulink environment, and experimentally. The estimated ON-state resistance values from the online setup are compared to offline measurements from an industrial curve tracer, where an overall estimation error of less than 1% is observed. The proposed solution maintains its estimation accuracy under variable load conditions and for different temperatures of the device under test.
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| 25. |
- Asoodar, Mohsen, et al.
(författare)
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Accurate Condition Monitoring of Semiconductor Devices in Cascaded H-Bridge Modular Multilevel Converters
- 2023
-
Ingår i: IEEE transactions on power electronics. - : Institute of Electrical and Electronics Engineers (IEEE). - 0885-8993 .- 1941-0107. ; 38:3, s. 3870-3884
-
Tidskriftsartikel (refereegranskat)abstract
- This article presents an online condition monitoring (CM) scheme for semiconductors used in modular multilevel converters (MMCs) that comprise cascaded H-bridge submodules. The CM algorithm is based on detecting changes in the ON-state resistance of the semiconductors over time. The proposed method is shown to successfully perform a curve tracing of semiconductors in MMCs while the semiconductor junction remains at a temperature that is readily measurable and undergoes minute changes during the measurement process. The ON-state resistance value is estimated from the measured ON-state voltage drop of the semiconductors and the measured arm current. Measuring the ON-state resistance at known temperatures allows for separating temperature-dependent variations of the ON-state resistance from age-dependent variations of this parameter. Suitable methods for reducing the effect of noise on the curve-traced data are proposed, and a recursive least square estimator is used to extract the optimum ON-state resistance from the traced v(CE) - i
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| 26. |
- Asoodar, Mohsen, et al.
(författare)
-
Online Health Monitoring of DC-Link Capacitors in Modular Multilevel Converters for FACTS and HVDC Applications
- 2021
-
Ingår i: IEEE transactions on power electronics. - : Institute of Electrical and Electronics Engineers (IEEE). - 0885-8993 .- 1941-0107. ; 36:12, s. 13489-13503
-
Tidskriftsartikel (refereegranskat)abstract
- This article presents an online health monitoring scheme for dc capacitors in modular multilevel converters (MMCs). The health monitoring algorithm is based on detecting changes in the dc capacitance value over time. The proposed algorithm only utilizes measurements that are typically available in flexible alternating current transmission systems and high-voltage direct current applications. Hence, in the proposed estimation method, no additional sensors are used. The estimation scheme considers the presence of noise in voltage and current measurements, and utilizes a recursive least square estimator in conjunction with a special low-pass filter to minimize the estimation errors. Simulation results of a hardware replica, as well as experimental results on a low-power MMC prototype show that the proposed scheme can identify the dc-link capacitance value with a maximum error of 1%.
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| 27. |
- Asoodar, Mohsen, et al.
(författare)
-
Temperature Considerations for Online Health Monitoring of DC-Link Capacitors in Modular Multilevel Converters
- 2021
-
Ingår i: 2021 23rd European Conference on Power Electronics and Applications, EPE 2021 ECCE Europe. - : Institute of Electrical and Electronics Engineers Inc..
-
Konferensbidrag (refereegranskat)abstract
- In this paper, the effect of temperature on online heath monitoring of dc capacitors in modular multilevel converters (MMCs) is studied. The submodule capacitance value is considered as the main indicator of health. Both self heating and ambient temperature are considered as sources of temperature variation. The study is conducted on a single phase MMC with full-bridge submodules. However, a similar analysis can be used for half-bridge MMCs and multiphase MMCs as well. The thermal behaviour of the capacitors is explained analytically and simulated using a simplified Cauer model. The effect of temperature on the estimated capacitance values is shown, and a method for reducing this effect is proposed. The results are verified using simulations in MATLAB/Simulink.
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| 28. |
- Augustin, Tim, et al.
(författare)
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Advanced Test Circuit for DC Circuit Breakers
- 2018
-
Ingår i: 20th European Conference on Power Electronics and Applications (EPE'18 ECCE EUROPE).
-
Konferensbidrag (refereegranskat)abstract
- In future HVDC systems, many DC circuit breakers (DCCBs) will be required. In this paper, an advanced test circuit for DCCBs is described. A DC source is combined with a capacitor bank. In contrast to other test circuits, the proposed test circuit allows to replicate constant DC and temporary faults. In addition to conventional faults, this enables testing of auto-reclosing, proactive commutation, and complex test sequences combining all of these modes. The test circuit is easy to setup and also suitable for smaller research facilities. Experimental results from a down-scaled mock-up are included to demonstrate the capabilities of the test circuit.
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| 29. |
- Augustin, Tim, et al.
(författare)
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Enhanced Active Resonant DC Circuit Breakers Based on Discharge Closing Switches
- 2021
-
Ingår i: IEEE Transactions on Power Delivery. - : IEEE. - 0885-8977 .- 1937-4208. ; 36:3, s. 1735-1743
-
Tidskriftsartikel (refereegranskat)abstract
- Direct current circuit breakers (DCCBs) have become a large research topic and are considered one of the critical components for future DC grids. Proposed DCCB concepts may be grouped into hybrid DCCBs and active resonant DCCBs. In this work, the enhanced active resonant (EAR) DCCB family is introduced. EAR DCCBs combine elements of hybrid and active resonant DCCBs. The EAR DCCB family consists of one unidirectional and six bidirectional concepts. All concepts feature proactive commutation. The main characteristic of the EAR DCCBs is that discharge closing switches are used instead of semiconductors with turn-off capability. Relevant discharge closing switch technology is reviewed, a laboratory prototype is explained, and experimental results are presented to demonstrate the feasibility of the proposed DCCB concepts.
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| 30. |
- Augustin, Tim, et al.
(författare)
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Experimental Study of Enhanced Active Resonant DC Circuit Breakers
- 2022
-
Ingår i: IEEE transactions on power electronics. - : Institute of Electrical and Electronics Engineers (IEEE). - 0885-8993 .- 1941-0107. ; 37:5, s. 5687-5698
-
Tidskriftsartikel (refereegranskat)abstract
- Enhanced active resonant (EAR) dc circuit breakers (DCCBs) are a novel type of DCCB that use a discharge closing switch as interruption medium. A technical limitation of discharge closing switches is the minimum voltage across the main gap required for successful triggering. A novel commutation process creating the minimum voltage internally is proposed, which allows to simplify the EAR DCCB configuration and to reduce its component count. In the prototype, the discharge closing switch is implemented with a TVG. Experiments show that the TVG can be triggered reliably down to a voltage of 50 V and that the discharge in the TVG is highly oscillatory at low current. The originally proposed EAR DCCB configuration has to be tuned such that the commutation to the TVG succeeds at low current. Conversely, the novel commutation process decouples the minimum voltage from the current level by adjusting the triggering delay. This allows reliable commutation irrespective of the operating conditions. It is shown that the novel commutation process does not adversely affect dc interruption. Proactive commutation operation and auto-reclosing strategies are demonstrated.
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| 31. |
- Augustin, Tim, et al.
(författare)
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Modelling of HVDC breakers for HVDC grid simulations
- 2017
-
Ingår i: IET Conference Publications. - : Institution of Engineering and Technology.
-
Konferensbidrag (refereegranskat)abstract
- This paper deals with the modelling of high-voltage direct current (HVDC) breakers in PSCAD. The models are aimed at HVDC grid simulation and are kept as simple as possible. An overview is given over recently proposed HVDC breaker concepts. Assumptions and simplifications are explained as well. The main result is that even these simplified models are too detailed for grid simulations. The reason for this is that from a grid perpective the only thing that matters is when the metal-oxide varistor is inserted. The models can be used to estimate interruption times.
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| 32. |
- Augustin, Tim, et al.
(författare)
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System Design of Fast Actuator for Vacuum Interrupter in DC Applications
- 2018
-
Ingår i: 2018 28th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV). - : Institute of Electrical and Electronics Engineers (IEEE). - 9781538643730 ; , s. 527-530
-
Konferensbidrag (refereegranskat)abstract
- One of the major challenges of DC circuit breakers is the required fast mechanical actuator. In this paper, a Thomson coil actuator system for a vacuum interrupter is designed. Active damping is used to decelerate the moving contacts. Challenges are discussed, especially concerning the power supply needed for the Thomson coil actuator. The design philosophy is explained and FEM simulation results are presented. The results indicate that a wide range of combinations of drive circuit capacitance and voltage fulfill the requirements for armature acceleration. However, active damping requires a very careful selection of drive circuit voltage and timing of applied damping.
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| 33. |
- Augustin, Tim, et al.
(författare)
-
Thomson-Coil Actuator System for Enhanced Active Resonant DC Circuit Breakers
- 2022
-
Ingår i: IEEE Journal of Emerging and Selected Topics in Power Electronics. - : Institute of Electrical and Electronics Engineers (IEEE). - 2168-6777 .- 2168-6785. ; 10:1, s. 800-810
-
Tidskriftsartikel (refereegranskat)abstract
- Enhanced active resonant (EAR) dc circuit breakers (DCCBs) are a promising set of recently proposed DCCB concepts. As other DCCBs, EAR DCCBs still require a fast mechanical switch. The requirements on the actuator of the mechanical switch depend on the DCCB concept and the dc grid and are derived here for an EAR DCCB. Thomson-coil actuators (TCAs) can open and close mechanical switches sufficiently fast to satisfy the requirements. This work studies experimentally a TCA system with active damping for an off-the-shelf industrial vacuum interrupter used as mechanical switch in an EAR DCCB. The prototype is explained in detail, and extensive measurement results are presented, showing that active damping must be perfectly timed to be effective. A novel Thomson-coil (TC) driver is proposed and studied experimentally, which operates the TCA more efficiently by recycling energy during the actuation. Moreover, the novel TC driver reduces the capacitive storage by 50% and allows for faster recharging with lower charging current. Finally, the autoreclosing and proactive commutation operation of the TCA system and the interruption capability of the prototype EAR DCCB are demonstrated experimentally.
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| 34. |
- Augustin, Tim, et al.
(författare)
-
Transient Behaviour of VSC-HVDC Links with DC Breakers Under Faults
- 2017
-
Ingår i: 2017 19th European Conference on Power Electronics and Applications (EPE'17 ECCE EUROPE). - : Institute of Electrical and Electronics Engineers (IEEE). - 9789075815276
-
Konferensbidrag (refereegranskat)abstract
- In future high-voltage direct current (HVDC) systems, a large number of HVDC breakers will be required.In this paper, the influence of HVDC breakers on the transient performance of point-to-point HVDC links in both asymmetrical and symmetrical monopolar configuration with half-bridge modular multilevel converters is studied with simulations in PSCAD. As HVDC breakers, the active resonant breaker and ABB’s hybrid breaker are considered. The analyzed scenarios include DC line faults, DC bus faults, and AC faults between the converter and the transformer. The highest DC breaking capability is required during DC line faults in the asymmetric and symmetric monopole. The converter stress is highest for DC bus faults and unbalanced converter AC faults in the asymmetric monopole and for DC bus pole-to-pole faults in the symmetric monopole. During DC pole-to-ground faults in the symmetric monopole, the HVDC breaker combined with DC side arrestors yields the lowest overvoltage stress on the cable of the healthy pole. The fault current shapes depend strongly on the interaction of the converter and the travelling waves on the lines, and differ from the fault current shapes in typical HVDC breaker test circuits. Furthermore, the active resonant breaker and the ABB hybrid breaker perform similarly in the used benchmarks due to the very fast DC line fault detection.
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| 35. |
- Bakas, Panagiotis, et al.
(författare)
-
Design considerations and comparison of hybrid line-commutated and cascaded full-bridge converters with reactive-power compensation and active filtering capabilities
- 2019
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper compares two hybrid topologies that combine the line-commutated converter (LCC) with cascaded full-bridge (FB) converters. The latter are utilized for compensating the reactive power and filtering the current harmonics of the LCC. The method that was developed for dimensioning these hybrid topologies is presented in detail. This method is utilized for calculating the arm voltage and current waveforms, which are used to estimate other important quantities, such as conduction losses and energy variations. Finally, the studied converters are compared in terms of voltage/current ratings, semiconductor requirements, conduction losses, and energy variations.
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| 36. |
- Bakas, Panagiotis, et al.
(författare)
-
Hybrid alternate-common-arm converter with director thyristors - Impact of commutation time on the active-power capability
- 2019
-
Ingår i: 2019 21st European Conference on Power Electronics and Applications, EPE 2019 ECCE Europe. - Genova, Italy : Institute of Electrical and Electronics Engineers Inc.. - 9789075815313 - 9781728123615
-
Konferensbidrag (refereegranskat)abstract
- This paper investigates the impact of the thyristor commutation time on the peak currents and the active-power capability of the hybrid alternate-common-arm converter (HACC). This converter employs director thyristors for the alternate connection of a common arm in parallel to the main arms. The parallel connection enables current sharing among the arms, which allows the HACC to transfer higher output power without increasing the peak arm current. It is shown that the active-power capability of the HACC is doubled for a certain current-sharing factor, which, however, is altered by the thyristor commutation time. Therefore, the impact of the commutation time on the active-power capability of the HACC is investigated theoretically. Finally, this analysis is verified by simulation results.
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| 37. |
- Bakas, Panagiotis, et al.
(författare)
-
Hybrid alternate-common-arm converter with high power capability : Potential and limitations
- 2020
-
Ingår i: IEEE transactions on power electronics. - : IEEE. - 0885-8993 .- 1941-0107. ; 35:12, s. 12909-12928
-
Tidskriftsartikel (refereegranskat)abstract
- This paper studies a new hybrid converter thatutilizes thyristors and full-bridge (FB) arms for achieving higherpower capability than the full-bridge (FB) modular multilevel converter (MMC) with reduced semiconductor requirements. The study covers the theoretical analysis of the energy balancing,the dimensioning principles, the maximum power capability, and the limitations imposed by the discontinuous operation of theconverter. Based on the analysis of these aspects, the theoretical analysis is concluded by identifying the design constraints that need to be fulfilled for achieving the maximum power capabilityof the converter. It is concluded that the maximum power capability can be achieved for a certain range of modulation indices and is limited by both the commutation time of the thyristors andthe power angle. Finally, simulation and experimental results that confirm the theoretical analysis and the feasibility of the studied converter are presented and discussed.
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| 38. |
- Bakas, Panagiotis, et al.
(författare)
-
Hybrid Converter With Alternate Common Arm and Director Thyristors for High-Power Capability
- 2018
-
Ingår i: 2018 20th European Conference on Power Electronics and Applications (EPE’18 ECCE Europe).
-
Konferensbidrag (refereegranskat)abstract
- This paper presents the basic operating principles of a new hybrid converter that combines thyristors and full-bridge (FB) arms for achieving high active-power capability. This converter consists of a modular multilevel converter (MMC) equipped with additional common arms, which alternate between the upper and lower dc poles. This alternation is achieved by the thyristors that are utilized as director switches and allow the parallel connection of the common arms and the arms of the MMC. The main contributions of this paper are the analysis of the operating principles, the simulation verification of the functionality of the proposed converter, and the comparison of the latter with the full-bridge modular multilevel converter (FB-MMC).
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| 39. |
- Bakas, Panagiotis
(författare)
-
Hybrid Converters for HVDC Transmission
- 2019
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The line-commutated converter (LCC) and the voltage-source converter (VSC) are the two main converter technologies utilized in high-voltage direct current (HVDC) transmission applications. Depending on the application requirements, one technology might be more advantageous than the other. On the one hand, the LCC features technological maturity, high efficiency, and high power-transfer capability, but it lacks the ability to independently control active and reactive power and to ride through ac faults. On the other hand, the VSC overcomes the shortcomings of the LCC and offers more functionality, as it features the ability to independently control active and reactive power, ac-fault ride through capability, black-start capability, and superior harmonic performance. Yet, it is less mature, less efficient, and has lower power-transfer capability than the LCC. Thus, the combination of the LCC and the VSC topologies could yield hybrid converters that leverage the complementary characteristics of both technologies and thus are optimized for HVDC applications. Therefore, the main objective of this thesis is to investigate existing and derive new hybrid converters that combine the complementary characteristics of the LCC and VSC technologies.The hybrid converters investigated in this thesis are divided in two main categories, namely: (a) current-source; and (b) voltage-source hybrid converters. The former category includes hybrid converters that are based on the LCC structure and utilize a VSC part either for compensating the reactive power consumed by the LCC, or for active filtering of the LCC current harmonics, or for independently controlling active and reactive power, or for achieving a combination of these functionalities. Four different current-source hybrid converters have been investigated and compared in terms of functionality, conduction losses, and semiconductor requirements.The second category includes more complex circuits that combine thyristors and modular VSC elements in ways that enable these hybrid converters to operate as VSCs and to achieve high active-power capability. Two new voltage-source hybrid converters are analyzed and compared in terms of active-power capability, semiconductor requirements, and controllability. This study reveals that the hybrid alternate-common-arm converter (HACC) is the most interesting circuit; thus, an in-depth analysis is performed for this converter. The theoretical analysis shows that, under certain operating conditions, the HACC can transfer twice the active power of the full-bridge modular multilevel converter (FB-MMC) with lower semiconductor rating per unit of active power. Yet, if the total commutation time of the thyristors and/or the power angle are increased beyond certain values, the active-power capability of the HACC is reduced. Finally, simulation and experimental results are provided in order to verify the theoretical analysis and prove the feasibility of the HACC.
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| 40. |
- Bhadoria, Shubhangi, et al.
(författare)
-
Comparison of Top and Bottom Cooling for Short Duration of Over-Currents for SiC Devices: An Analysis of the Quantity and Location of Heat-Absorbing Materials
- 2024
-
Ingår i: IEEE Open Journal of Power Electronics. - : Institute of Electrical and Electronics Engineers (IEEE). - 2644-1314. ; 5, s. 765-778
-
Tidskriftsartikel (refereegranskat)abstract
- The fault clearance time in the power system can vary from a few milliseconds to a few hundred milliseconds. Power electronics converters should be able to provide the increased current during faults without failing due to thermal limits. Hence, the heat generated in the semiconductor chip due to the over-current (OC) should be removed as soon as it is generated. In this paper, cooling by heat-absorbing material has been investigated on the top, bottom, and top + bottom of the SiC MOSFET chip using COMSOL simulations for OCs. The heat-absorbing materials considered in the paper are copper, graphite, and aluminum. The maximum allowed chip temperature is assumed to be 250 ˆC since SiC devices do not fail in this range of temperature. It is concluded that the cooling on the top of the chip has the best performance among the three arrangements discussed in the paper in terms of OC duration and steady-state temperature. Another conclusion is that copper has the best performance due to higher thermal capacity for the same volume of the heat-absorbing material.
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| 41. |
- Bhadoria, Shubhangi, et al.
(författare)
-
Enablers for Overcurrent Capability of Silicon-Carbide-Based Power Converters : An Overview
- 2023
-
Ingår i: IEEE transactions on power electronics. - : Institute of Electrical and Electronics Engineers Inc.. - 0885-8993 .- 1941-0107. ; 38:3, s. 3569-3589
-
Tidskriftsartikel (refereegranskat)abstract
- With the increase in penetration of power electronic converters in the power systems, a demand for overcurrent/ overloading capability has risen for the fault clearance duration. This article gives an overview of the limiting factors and the recent technologies for the overcurrent performance of SiC power modules in power electronics converters. It presents the limitations produced at the power module level by packaging materials, which include semiconductor chips, substrates, metallization, bonding techniques, die attach, and encapsulation materials. Specifically, technologies for overcurrent related temperatures in excess of 200°C are discussed. This article also discusses potential technologies, which have been proven or may be potential candidates for improving the safe operating area. The discussed technologies are use of phase-change materials below the semiconductor chip, Peltier elements, new layouts of the power modules, control and modulation techniques for converters. Special attention has been given to an overview of various potential phase-change materials, which can be considered for high-temperature operations.
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| 42. |
- Bhadoria, Shubhangi, et al.
(författare)
-
Enabling Short-Term Over-current Capability of SiC Devices using Microchannel Cooling
- 2023
-
Ingår i: Proceedings 29th International Workshop on Thermal Investigations of ICs and Systems (THERMINIC). - : Institute of Electrical and Electronics Engineers (IEEE).
-
Konferensbidrag (refereegranskat)abstract
- Fault clearance time in the power system with renewables generally varies from 0.5-10 cycles (10-667 ms for 50 Hz). Power electronic converters should be able to provide an increased current without exceeding the thermal limits during faults. Accordingly, the heat generated in the semiconductor chip during over-current (OCs) should be removed from the chip as soon as it is generated. In this paper, microchannel (MC) cooling has been investigated through COMSOL simulations for OCs with SiC MOSFETs. The upper limit of the chip temperature has been assumed to be 250 °C as SiC devices do not fail in this temperature range. The duration of OCs is from a few tens of milliseconds to a few seconds. It is concluded that MC cooling has the potential to increase the duration of OC without reaching the assumed upper limit of the temperature.
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| 43. |
- Bhadoria, Shubhangi, et al.
(författare)
-
Over-current Capability of SiC Devices for Short Power and Heat Pulses
- 2023
-
Ingår i: 2023 24th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems, EuroSimE 2023. - : Institute of Electrical and Electronics Engineers (IEEE).
-
Konferensbidrag (refereegranskat)abstract
- Unsymmetrical faults in the power system typically last for approximately 200 ms until the circuit breakers clear the faults. Hence, it is important to ensure that power semiconductors in converters do not fail due to the associated increased current. This is possible if the heat generated in the SiC device due to over-currents (OCs) is removed as soon as possible. Various materials such as metals (copper, aluminum, nickel, silver and gold), diamond, graphite and phase change materials for removing the heat just below/above the semiconductor have been considered in this paper. The calculations and COMSOL simulations have been performed assuming a heat pulse on one side of the material and adiabatic conditions on the other side. This assumption is valid for short pulses as the components further away would take more time to absorb heat. It has been concluded that the higher thermal conductivity, the faster is the removal of the heat from the semiconductor. Because of this, metals, diamond and graphite have been proven to be more effective in heat removal and keeping the temperature below 250°C during OCs for the heat pulse of 400 W/cm2 for 200 ms. The concept of sensible height and limitations of the use of the materials is also discussed. There is a limit to the reduction of junction temperature by adding and increasing the amount of material above the chip. After this limit, the further reduction of junction temperature is not possible, even by increasing the amount of material. This limit reached is different for different materials.
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| 44. |
- Bhadoria, Shubhangi, et al.
(författare)
-
Over-Current Capability of Silicon Carbide and Silicon Devices for Short Power Pulses with Copper and Phase Change Materials below the Chip
- 2024
-
Ingår i: Energies. - : MDPI. - 1996-1073. ; 17:2, s. 462-
-
Tidskriftsartikel (refereegranskat)abstract
- An increasing share of fluctuating and intermittent renewable energy sources can cause over-currents (OCs) in the power system. The heat generated during OCs increases the junction temperature of semiconductor devices and could even lead to thermal runaway if thermal limits are reached. In order to keep the junction temperature within the thermal limit of the semiconductor, the power module structure with heat-absorbing material below the chip is investigated through COMSOL Multiphysics simulations. The upper limits of the junction temperature for Silicon (Si) and Silicon Carbide (SiC) are assumed to be 175 and 250 ∘∘C, respectively. The heat-absorbing materials considered for analysis are a copper block and a copper block with phase change materials (PCMs). Two times, three times, and four times of OCs would be discussed for durations of a few hundred milliseconds and seconds. This article also discusses the thermal performance of a copper block and a copper block with PCMs. PCMs used for Si and SiC are LM108 and Lithium, respectively. It is concluded that the copper block just below the semiconductor chip would enable OC capability in Si and SiC devices and would be more convenient to manufacture as compared to the copper block with PCM.
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| 45. |
- Cai, Yumeng, et al.
(författare)
-
Characterization of Gate-Oxide Degradation Location for SiC MOSFETs Based on the Split C-V Method Under Bias Temperature Instability Conditions
- 2023
-
Ingår i: IEEE transactions on power electronics. - : Institute of Electrical and Electronics Engineers (IEEE). - 0885-8993 .- 1941-0107. ; 38:5, s. 6081-6093
-
Tidskriftsartikel (refereegranskat)abstract
- Gate-oxide degradation has been one of the major reliability challenges of SiC mosfets. Comprehensive and accurate localization of gate-oxide degradation under bias temperature instability (BTI) conditions is important to improve the device reliability. The split C-V [gate-source capacitance C-GS (v(G)) and gate-drain capacitance C-GD (v(G))] method is proposed in this article to locate gate-oxide degradation. Moreover, a BTI automated characterization system integrated I-V and split C-V test is presented. The effect of gate-oxide degradation on threshold voltage and split C-V under dc and ac BTI conditions is investigated and the degradation location is analyzed. Furthermore, the degradation simulation is conducted with technology computer aided design (TCAD) to reveal the mechanism. The results show that the different parts of split C-V can characterize degradation location, the type, and energy level of traps. The acceptor traps near valence band and donor traps near conduction band cause gate-oxide degradation above the channel and junction field effect transistor (JFET) region in positive bias temperature instability (PBTI) and Negative Bias Temperature Instability (NBTI), respectively. In ac BTI, the gate-oxide degradation at the channel region is independent of v(G) polarity, while the opposite is true above JFET region. These findings help to improve the long-term operation reliability of gate oxide from the perspective of chip design and application.
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| 46. |
- Cai, Yumeng, et al.
(författare)
-
Simulation Study of the Effect of Threshold Voltage Hysteresis on Switching Characteristics of SiC MOSFETs
- 2023
-
Ingår i: International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management, PCIM Europe 2023. - : Mesago PCIM GmbH. ; , s. 212-216
-
Konferensbidrag (refereegranskat)abstract
- The effect of VTH hysteresis on switching characteristics of SiC MOSFETs is investigated by TCAD in this paper. A device-circuit mixed-mode simulation model is built to simulate VTH hysteresis. The result illustrates that VTH hysteresis decreases VTH and increases channel mobility, which leads to earlier turn-on and larger ID. Moreover, the higher the interface state density (Dit) is, the more obvious the transient effect. However, ID remains unchanged with VTH hysteresis and it decreases with higher Dit without considering VTH hysteresis. Therefore, the VTH hysteresis is beneficial and the findings can be useful for distributing Dit when modeling the chip process.
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| 47. |
- Cao, Xin, et al.
(författare)
-
A New Method for Simplifying Complex DC Systems and Obtaining the Controller Droop Coefficients
- 2022
-
Ingår i: IEEE Transactions on Power Systems. - : Institute of Electrical and Electronics Engineers (IEEE). - 0885-8950 .- 1558-0679. ; 37:2, s. 996-1006
-
Tidskriftsartikel (refereegranskat)abstract
- DC grid has become an important application in power transmission. However, the exist works only have the method to obtain the droop coefficient in a radial topology. Also, this droop coefficient is for V-I droop control. There is no such like method to obtain the droop coefficient for the P-V droop control. This paper proposed a new method for a complex dc grid to obtain the droop coefficients. Firstly, based on the converter control strategies, the types of converter were classified. It will help to find out which kinds of converter can be participated into the dc-side voltage control. Secondly, a virtual node was defined, and the matrix of the dc grid was reshaped to fit the new added virtual node by using the proposed simplification method. An example was shown how this method worked. After that a new method of calculating the P-V droop coefficient was proposed. Finally, a simulation model was investigated to verify if the proposed method can operate in a real system. The results showed that the simplification method can ensure the mathematical relationships of the dc system. And simulations show good performances of the droop coefficient calculation method.
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| 48. |
- Ciftci, Baris, 1987-, et al.
(författare)
-
A Proposal for Wireless Control of Submodules in Modular Multilevel Converters
- 2018
-
Konferensbidrag (refereegranskat)abstract
- The modular multilevel converter is one of the most preferred converters for high-power conversion applications. Wireless control of the submodules can contribute to its evolution by lowering the material and labor costs of cabling and by increasing the availability of the converter. However, wireless control leads to many challenges for the control and modulation of the converter as well as for proper low-latency high-reliability communication. This paper investigates the tolerable asynchronism between phase-shifted carriers used in modulation from a wireless control point of view and proposes a control method along with communication protocol for wireless control. The functionality of the proposed method is validated by computer simulations in steady state.
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| 49. |
- Ciftci, Baris, et al.
(författare)
-
Simple Distributed Control for Modular Multilevel Converters
- 2019
-
Ingår i: 2019 21st European Conference on Power Electronics and Applications, EPE 2019 ECCE Europe. - Brussels : European Power Electronics and Drives Association. - 9789075815306
-
Konferensbidrag (refereegranskat)abstract
- The central control of MMC becomes demanding in computation power and communication bandwidth as the number of submodules increase. Distributed control methods can overcome these bottlenecks. In this paper, a simple distributed control method together with synchronization of modulation carriers in the submodules is presented. The proposal is implemented on a lab-scale MMC with asynchronous-serial communication on a star network between the central and local controllers. It is shown that the proposed control method works satisfactorily in the steady state. The method can be applied as is to MMCs with any number of submodules per arm.
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| 50. |
- Ciftci, Baris, et al.
(författare)
-
Wireless Communication in Modular Multilevel Converters and Electromagnetic Interference Characterization
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The wireless control of modular multilevel converter (MMC) submodules was recently proposed. The success of the control depends on specialized control methods suitable for wireless communication and a properly designed wireless communication network in the MMC valve hall while aiming for low latency and high reliability. The wireless communication in the hall can be affected by the electromagnetic interference (EMI) of MMC submodules, voltage and current transients. In this article, firstly, a wireless communication network based on 5G New Radio is designed for an example full-scale MMC valve hall. After that, radiated EMI characteristics of MMC submodules with different voltage and current ratings and two dc circuit breakers are measured. The effects of EMI on wireless communication in the multi-GHz frequency band are tested. The interference from the components is confined below 500 MHz, and the wireless communication with 5825 MHz center frequency is not affected by the interference.
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