| 1. |
- Behrouzian, Ehsan, 1985, et al.
(författare)
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DC-link voltage modulation for individual capacitor voltage balancing in cascaded H-bridge STATCOM at zero current mode
- 2018
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Ingår i: 2018 20th European Conference on Power Electronics and Applications, EPE 2018 ECCE Europe. - 9789075815283
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Konferensbidrag (refereegranskat)abstract
- Individual capacitor voltage balancing of cascaded H-Bridge converters is one of the challenges in the field of multilevel converters, especially when the converter is operating at zero-current mode. This is due to the fact that the balancing algorithm requires information about the power direction for proper insertion of the different cells of the converter. In case of delta configuration of the phase-legs of the converter, a circulating current inside the delta can be used for balancing purposes. However, this approach can not be used for the star configuration. Focusing on the star, this paper first highlights the issue related to the capacitor voltage balancing at zero-current mode and second proposes a novel method to overcome this problem. The proposed method is based on modulation of the DC-link voltages. The method provides a small amount of current flow during the zero-current mode operation. This current enables the sorting algorithm to provide an appropriate individual balancing. The proposed method is applied to a 7-level star connected cascaded H-Bridge STATCOM modeled in PSCAD and simulation results show the effectiveness of the proposed method in balancing the capacitors voltages when no current is exchanged with the grid. Finally the proposed method is experimentally verified through a down-scaled laboratory set-up.
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| 2. |
- Heinig, Stefanie, et al.
(författare)
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Reduction of Switching Frequency for the Semi-Full-Bridge Submodule Using Alternative Bypass States
- 2018
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Ingår i: 2018 20TH EUROPEAN CONFERENCE ON POWER ELECTRONICS AND APPLICATIONS (EPE'18 ECCE EUROPE). - : IEEE. - 9789075815283
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Konferensbidrag (refereegranskat)abstract
- As regards modular multilevel converter submodules, a different number of switches may be involved in the transitions between voltage levels depending on the submodule type and choice of switching states. In this paper, an investigation of the average switching frequency associated with different choices of bypass states is performed for the semi-full-bridge submodule. Theoretical considerations and simulation results show that the average switching frequency per device can be halved by using the proposed alternative bypass state. Moreover, the switching losses can be reduced by up to 60%. Finally, a comparative study with the full-bridge submodule has been conducted.
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| 3. |
- Kersten, Anton, 1991, et al.
(författare)
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Efficiency of Active Three-Level and Five-Level NPC Inverters Compared to a Two-Level Inverter in a Vehicle
- 2018
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Ingår i: 2018 20th European Conference on Power Electronics and Applications, EPE 2018 ECCE Europe. - 9789075815283 ; , s. 1-9
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Konferensbidrag (refereegranskat)abstract
- This paper deals with a comparison of a standard two-level inverter, with a three-level and a five-level active neutral point clamped (ANPC) inverter for vehicle traction applications. The inverter efficiencies during different drive cycles are assessed and an efficiency enhancement of the multilevel inverters for partial loading and different drive cycle scenarios is found.
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| 4. |
- Nikouei, Mojgan, et al.
(författare)
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Torque-Ripple Minimization for Permanent-Magnet Synchronous Motors Based on Harmonic Flux Estimation
- 2018
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Ingår i: 2018 20Th European Conference On Power Electronics And Applications (Epe'18 Ecce Europe). - : IEEE. - 9789075815283
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Konferensbidrag (refereegranskat)abstract
- This paper presents a control algorithm to reduce the torque ripple in permanent-magnet synchronous motors. This control algorithm is based on the on-line estimation of harmonic flux linkage. Together with the on-line estimation of the flux linkage, a proportional-integral-resonant controller is introduced to suppress the torque ripple.
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| 5. |
- Sadik, Diane, 1988-, et al.
(författare)
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Effect of Parasitic Inductance in a Soft-Switching SiC Power Converter
- 2018
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Ingår i: 2018 20TH EUROPEAN CONFERENCE ON POWER ELECTRONICS AND APPLICATIONS (EPE'18 ECCE EUROPE). - : IEEE. - 9789075815283
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Konferensbidrag (refereegranskat)abstract
- Wide Bandgap power semiconductors such as SiC MOSFETs, have enabled compact and highly efficient power converters operated at higher frequencies. However, parasitic inductance of the package may significantly increase power losses and limit the operation. This paper aims to quantify experimentally these losses in a soft-switching converter. A "removable" stray inductance is implemented in a setup consisting of discrete SiC MOSFET units. Thus, the power loss of the transistors with and without stray inductance can be compared. Similarly slower switching speeds are also implemented to fully emulate a 62-mm module. The power loss induced by the package can thus be evaluated.
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| 6. |
- Sadik, Diane, 1988-, et al.
(författare)
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Effect of Parasitic Inductance in a Soft-Switching SiC Power Converter Topics : 1 b: New Materials and Active Devices 7b: High-voltage DC Power Supplies (U)
- 2018
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Ingår i: 2018 20th European Conference on Power Electronics and Applications, EPE 2018 ECCE Europe. - : Institute of Electrical and Electronics Engineers Inc.. - 9789075815283
-
Konferensbidrag (refereegranskat)abstract
- Wide Bandgap power semiconductors such as SiC MOSFETs, have enabled compact and highly efficient power converters operated at higher frequencies. However, parasitic inductance of the package may significantly increase power losses and limit the operation. This paper aims to quantify experimentally these losses in a soft-switching converter. A 'removable' stray inductance is implemented in a setup consisting of discrete SiC MOSFET units. Thus, the power loss of the transistors with and without stray inductance can be compared. Similarly slower switching speeds are also implemented to fully emulate a 62-mm module. The power loss induced by the package can thus be evaluated.
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