| 1. |
- Antonello, Riccardo, et al.
(author)
-
Self-commissioning calculation of dynamic models for synchronous machines with magnetic saturation using flux as state variable
- 2019
-
In: The Journal of Engineering. - : Institution of Engineering and Technology. - 2051-3305. ; :17, s. 3609-3613
-
Journal article (peer-reviewed)abstract
- This paper deals with the non-linear modelling of synchronous machines by using the flux linkage as a state variable.The model is inferred from a conventional set of measurements where the relation between the currents and the flux linkages inthe rotating reference frame (also known as dq reference frame) are known by measurements or estimated through finite-element simulations. In particular, the contribution of this paper is twofold: first, it proposes a method to extract the non-linearmodel information which can be easily implemented in electric drives, without the need of offline post-processing of the data.Second, it mathematically demonstrates that the method converges to the final result in a stable way. An example based onexperimental measurements of the current-to-flux look-up tables of an 11-kW synchronous reluctance machine is shown,proving the feasibility of the proposed method.
|
|
| 2. |
- Aziz, Imran, et al.
(author)
-
60 GHz compact broadband antenna arrays with wide-angle beam steering
- 2019
-
In: The Journal of Engineering. - : INST ENGINEERING TECHNOLOGY-IET. - 2051-3305. ; :8, s. 5407-5414
-
Journal article (peer-reviewed)abstract
- Highly integrated multilayered printed circuit board-based patch antenna arrays are proposed in this study for 60 GHz wireless communications. Electromagnetic coupling between two stacked patches is used to achieve the broadband performance. Different structures of single element antennas, two-element antenna arrays and four-element antenna arrays are presented. The two compact four-element antenna arrays show < -10 dB impedance bandwidth of 13 and 14.6% with 12 dBi peak gain. The arrays have the 3 dB gain bandwidth of 9 and 13%. A single column, four-element sub-array is used to design 4 x 16 antenna array. This array delivers 20.8 dBi peak gain with 13% impedance and gain bandwidth. Furthermore, a two-element series fed array is used to realise a 2 x 16 phased antenna array. This array is fed through a 16 x channel radio frequency IC to achieve the beam steering in +/- 50 degrees range.
|
|
| 3. |
- Aziz, Imran, et al.
(author)
-
Effects of proton irradiation on 60 GHz CMOS transceiver chip for multi-Gbps communication in high-energy physics experiments
- 2019
-
In: The Journal of Engineering. - : INST ENGINEERING TECHNOLOGY-IET. - 2051-3305. ; :8, s. 5391-5396
-
Journal article (peer-reviewed)abstract
- This article presents the experimental results of 17 MeV proton irradiation on a 60 GHz low power, half-duplex transceiver (TRX) chip implemented in 65 nm CMOS technology. It supports short range point-to-point data rate up to 6 Gbps by employing on-off keying (OOK). To investigate the irradiation hardness for high-energy physics (HEP) applications, two TRX chips were irradiated with total ionising doses (TID) of 74 and 42 kGy and fluence of 1.4 x 10(14)N(eq)/cm(2) and 0.8 x 10(14)N(eq)/cm(2) for RX and TX modes, respectively. The chips were characterised by pre- and post-irradiation analogue voltage measurements on different circuit blocks as well as through the analysis of wireless transmission parameters like bit error rate (BER), eye diagram, jitter etc. Post-irradiation measurements have shown certain reduction in performance but both TRX chips have been found operational through over the air measurements at 5 Gbps. Moreover, very small shift in the carrier frequency was observed after the irradiation.
|
|
| 4. |
- Barzegaran, Mohammadreza, et al.
(author)
-
Electric drives as fog nodes in a fog computing-based industrial use case
- 2021
-
In: The Journal of Engineering. - : WILEY. - 2051-3305. ; 2021:12, s. 745-761
-
Journal article (peer-reviewed)abstract
- Electric drives, which are a main component in industrial applications, control electric motors and record vital information about their respective industrial processes. The development of electric drives as Fog nodes within a fog computing platform (FCP) leads to new abilities such as programmability, analytics, and connectivity, increasing their value. In this study, the FORA FCP reference architecture is used to implement electric drives as Fog nodes, which is called "fogification". The fogified drive architecture and its components are designed using Architecture Analysis and Design Language (AADL). The design process was driven by the high-level requirements that the authors elicited. Both the fogified drive architecture and the current drive architecture are used to implement a self baggage drop system in which electric drives are the key components. The fog-based design was then evaluated using several key performance indicators (KPIs), which reveal its advantages over the current drive architecture. The evaluation results show that safety-related isolation is enabled with only 9% overhead on the total Fog node utilization, control applications are virtualized with zero input-output jitter, the hardware cost is reduced by 44%, and machine learning at the edge is performed without interrupting the main drive functionalities and with an average 85% accuracy. The conclusion is that the fog-based design can successfully implement the required electric drive functionalities and can also enable innovative uses needed for realizing the vision of Industry 4.0.
|
|
| 5. |
- Baudoin, Antoine, et al.
(author)
-
Experimental results from a Thomson-coil actuator for a vacuum interrupter in an HVDC breaker
- 2019
-
In: The Journal of Engineering. - : INST ENGINEERING TECHNOLOGY-IET. - 2051-3305. ; :17, s. 3527-3531
-
Journal article (peer-reviewed)abstract
- Recent developments in high-voltage direct current transmission technology and the plans for multi-terminals motivate research efforts on the fast DC breaker. A novel concept to interrupt current up to several kiloamperes within a few milliseconds is presently under development, using a vacuum interrupter together with power electronics to create an artificial zero-crossing in the current through the switch. To achieve this objective, one critical component in the concept is an ultra-fast linear mechanical actuator. A prototype has been developed based on a Thomson coil. The experimental results are presented and show how a contact gap in a vacuum interrupter was effectively created in a controlled manner. Current of several kiloamperes was successfully interrupted within 3ms, thanks to the high-speed operation of the linear actuator.
|
|
| 6. |
- Fotouhi, Ali, 1983, et al.
(author)
-
Two-stage demand-side management in energy flexible residential buildings
- 2024
-
In: JOURNAL OF ENGINEERING-JOE. - 2051-3305. ; 2024:4
-
Journal article (peer-reviewed)abstract
- In this study, an optimisation model is developed for two-stage energy management of a residential building to minimise energy cost under monthly power-based tariffs for peak demand and time-variable electricity prices. The expected peak demand is determined in the first stage, and then the energy management system minimizes energy costs during the second stage. The second stage's optimisation problem is solved in a rolling time window, facilitating real-time operation of flexible energy sources in the building. This includes optimal charging and discharging of the battery energy system, electric vehicle battery charging, heating system operation, and determining the optimal start times for washing machines and dishwashers, all close to real-time. The proposed approach enables users to predict and manage peak demand in daily operation, staying below the predetermined value through a close to real-time energy management system. The effectiveness of this two-stage approach in demand-side management for residential buildings is demonstrated through a realistic case study. In this study, an optimisation model is developed for two-stage energy management of a residential building to minimise energy cost under monthly power-based tariffs for peak demand and time variable electricity prices. The expected peak demand is determined in the first stage, and then the energy management system minimises the energy cost in the second stage. The optimisation problem of the second stage is solved in a rolling time window for the real time operation of the flexible energy sources in the building. image
|
|
| 7. |
- Frost, Anna E., 1988-, et al.
(author)
-
Power flow in the air gap of linear electrical machines by utilization of the Poynting vector : Part 1 - Analytical expressions
- 2022
-
In: The Journal of Engineering. - : Institution of Engineering and Technology (IET). - 2051-3305. ; 2022:4, s. 377-388
-
Journal article (peer-reviewed)abstract
- Analytical solutions and estimations for the power flow in the air gap of linear electrical machines of different geometries are derived from Poynting's theorem. The different geometries considered are flat one-sided, multi-sided, and tubular linear electrical machines. The radial power flow for all considered geometries is dependent on the area of the air gap, the electric field, the magnetic field, and the load angle. The tangential power flow for both flat one-sided and tubular linear electrical machines is dependent of the area of the air gap, number of poles, the electric field, the magnetic field, and the load angle. The number of poles could be increased to decrease the tangential power flow in flat linear electrical machines. The expression for the tangential flow in tubular linear electrical machines is so complicated that it is difficult to draw conclusions from it.
|
|
| 8. |
- Frost, Anna E., 1988-, et al.
(author)
-
Power flow in the air gap of linear electrical machines by utilization of the Poynting vector : Part 2 - Simulations
- 2022
-
In: The Journal of Engineering. - : Institution of Engineering and Technology. - 2051-3305. ; 2022:9, s. 883-891
-
Journal article (peer-reviewed)abstract
- Different types of linear generators are simulated and their power flow in the air gap is investigated. The results are compared to the analytical expressions derived in Part 1. The simulations and the analytical expressions in Part 1 show the same general behavior, but the magnitudes are lower for the analytical expressions. One explanation for the difference in magnitude can be that the harmonics of the electric and magnetic fields contribute to the power flow, which is not accounted for in the analytical expressions. Due to results from Part 1, it is investigated if changing the number of poles can decrease the tangential power flow while the normal power flow stays the same. As was suspected, changing the number of poles affected several other factors, which lead to an increase in the normal power flow when increasing the number of poles, even though the electrical power was the same. The tangential power flow also decreased for three out of four generators. Thereby, increasing the number of poles with the same length of the machine, at the cost of reduced pole-pitch, should be done with precaution.
|
|
| 9. |
- Habib, Md Zakaria, et al.
(author)
-
Phase Shift Compensation Method for the Line Differential Protection on UHV-AC Transmission Lines
- 2018
-
In: The Journal of Engineering. - : Institution of Engineering and Technology (IET). - 2051-3305 .- 2051-3305.
-
Conference paper (peer-reviewed)abstract
- Line differential protection is popular for its good selectivity and simplicity as long as there is a dependable communication system between the two ends of the line. However, the sensitivity needs to be compromised when traditional line differential scheme is applied for UHV-AC lines because of the large charging current. This paper presents a study of the impact of UHV transmission line characteristics on line differential protection and a proposed solution based on compensation of the phase shift that exists between the sending and receiving end currents.
|
|
| 10. |
- Haghbin, Saeid, 1977, et al.
(author)
-
High-frequency modelling of a three-phase pulse width modulation inverter towards the dc bus considering line and controller harmonics
- 2014
-
In: The Journal of Engineering. - : Institution of Engineering and Technology (IET). - 2051-3305.
-
Journal article (peer-reviewed)abstract
- Closed-form analytical formulas are provided to calculate the dc bus harmonics of a three-phase sinusoidal pulse width modulation (SPWM) inverter. The harmonic analysis is performed by using a double Fourier series approach to determine the dc bus current frequency spectrum. For an arbitrary modulation index and load power factor, the full harmonic components of the inverter dc side current are calculated. Based on the developed analytical model, an equivalent circuit is proposed for the inverter harmonic analysis towards the dc bus. Moreover, the impacts of line harmonics and zero sequence injection in controller towards the dc bus are presented. The results show that the 5th and 7th ac line harmonics on the dc side current is appearance of the 6th harmonic in the dc side. The impact of zero sequence injection to the controller on the dc side is negligible. In addition to analytical formulation, different simulations and extensive measurements performed which the results verified the presented analytical framework.
|
|
