Pub Date : 2018-12-01DOI: 10.1109/SPEC.2018.8635639
A. Ebrahimi
The acceptability and also the acceleration of renewable energy technologies is tightly linked with a better understanding of dynamic behavior of drive train components and their interactions. This ultimate understanding of system characteristics can only be achieved with comprehensive experimental investigations on different phenomena of large electrical generators. This leads consequently to a better verification of numerical and analytical models of large generators. The large generator-converter lab which is discussed in this paper is a unique opportunity for deep experimental investigations on large hydro and wind generators. It is designed to deal with the current as well as future research topics in the field of wind and hydro generators and their interactions with power electronic devices and electrical grid.
{"title":"Characterization of a Large Electrical Machine Test Bench for Advanced Investigations on Wind and Hydro Generators","authors":"A. Ebrahimi","doi":"10.1109/SPEC.2018.8635639","DOIUrl":"https://doi.org/10.1109/SPEC.2018.8635639","url":null,"abstract":"The acceptability and also the acceleration of renewable energy technologies is tightly linked with a better understanding of dynamic behavior of drive train components and their interactions. This ultimate understanding of system characteristics can only be achieved with comprehensive experimental investigations on different phenomena of large electrical generators. This leads consequently to a better verification of numerical and analytical models of large generators. The large generator-converter lab which is discussed in this paper is a unique opportunity for deep experimental investigations on large hydro and wind generators. It is designed to deal with the current as well as future research topics in the field of wind and hydro generators and their interactions with power electronic devices and electrical grid.","PeriodicalId":335893,"journal":{"name":"2018 IEEE 4th Southern Power Electronics Conference (SPEC)","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132339289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Modular multilevel converters (MMC) have an inevitable double-frequency circulating current between phases because of the three-phase parallel structure. This leads to extra power loss of the converter. The traditional circulating current suppression strategy suppresses the double-frequency content by superimposing the circulating current suppression signal into the reference of upper and lower arms. Due to the addition of the suppression signal, the upper-and lower-arm modulation reference waves are distorted. That affects the quality of output waveform on AC voltage. This paper proposes a decoupled circulating current suppressing strategy which suppresses the circulating current without affecting the output waveform on the AC side. Simulation and experiment results show the effectiveness of the proposed strategy.
{"title":"A Decoupled Circulating Current Suppressing Strategy For Modular Multilevel Converter","authors":"Shukai Mao, Binbin Li, Shuxin Zhang, Dianguo Xu, Jizhong Chen, Xiaoqing Wang","doi":"10.1109/SPEC.2018.8636081","DOIUrl":"https://doi.org/10.1109/SPEC.2018.8636081","url":null,"abstract":"Modular multilevel converters (MMC) have an inevitable double-frequency circulating current between phases because of the three-phase parallel structure. This leads to extra power loss of the converter. The traditional circulating current suppression strategy suppresses the double-frequency content by superimposing the circulating current suppression signal into the reference of upper and lower arms. Due to the addition of the suppression signal, the upper-and lower-arm modulation reference waves are distorted. That affects the quality of output waveform on AC voltage. This paper proposes a decoupled circulating current suppressing strategy which suppresses the circulating current without affecting the output waveform on the AC side. Simulation and experiment results show the effectiveness of the proposed strategy.","PeriodicalId":335893,"journal":{"name":"2018 IEEE 4th Southern Power Electronics Conference (SPEC)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131171446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-01DOI: 10.1109/SPEC.2018.8635918
K. Sun, T. Summers, C. Coates
This paper proposes a new method to reduce the output current ripple in Cascaded H-bridge converter with Phase-Shifted Carrier PWM. The proposed technique introduces a new technique, namely Carrier Phase Angle Offset (CPAO), which changes the phase shift of the carriers between the phase legs of the converter. The mathematical analysis of the proposed technique is presented. Simulation results is provided to verify the theoretical analysis. The results show the proposed technique significantly reduces both the peak-to-peak and RMS current ripple.
{"title":"Current Ripple Reduction for Cascaded H-bridge Converter with Phase-Shifted Carrier PWM","authors":"K. Sun, T. Summers, C. Coates","doi":"10.1109/SPEC.2018.8635918","DOIUrl":"https://doi.org/10.1109/SPEC.2018.8635918","url":null,"abstract":"This paper proposes a new method to reduce the output current ripple in Cascaded H-bridge converter with Phase-Shifted Carrier PWM. The proposed technique introduces a new technique, namely Carrier Phase Angle Offset (CPAO), which changes the phase shift of the carriers between the phase legs of the converter. The mathematical analysis of the proposed technique is presented. Simulation results is provided to verify the theoretical analysis. The results show the proposed technique significantly reduces both the peak-to-peak and RMS current ripple.","PeriodicalId":335893,"journal":{"name":"2018 IEEE 4th Southern Power Electronics Conference (SPEC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130638130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-01DOI: 10.1109/SPEC.2018.8636056
Hejin Yang, Xinan Zhang, Wang Youyi
This paper presents a duty cycle based finite-set model predictive torque control (FS-MPTC) for permanent magnet synchronous motor drives. The proposed method contributes to significantly reduce torque ripples experienced in conventional FS-MPTC by using two voltage vectors (VVs) in one sampling cycle. The duty ratio of active VV is determined based on PI controller, which equivalently adjusts the weighting between torque and flux control in FS-MPTC. The validity of the proposed method is verified through simulations.
{"title":"A Duty Cycle based Finite-set Model Predictive Torque Control for Permanent Magnet Synchronous Motor Drives","authors":"Hejin Yang, Xinan Zhang, Wang Youyi","doi":"10.1109/SPEC.2018.8636056","DOIUrl":"https://doi.org/10.1109/SPEC.2018.8636056","url":null,"abstract":"This paper presents a duty cycle based finite-set model predictive torque control (FS-MPTC) for permanent magnet synchronous motor drives. The proposed method contributes to significantly reduce torque ripples experienced in conventional FS-MPTC by using two voltage vectors (VVs) in one sampling cycle. The duty ratio of active VV is determined based on PI controller, which equivalently adjusts the weighting between torque and flux control in FS-MPTC. The validity of the proposed method is verified through simulations.","PeriodicalId":335893,"journal":{"name":"2018 IEEE 4th Southern Power Electronics Conference (SPEC)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122872824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-01DOI: 10.1109/SPEC.2018.8635967
R. García, J. Pinto, I. S. Ono, Vitoria dos Santos Fahed, M. Brito
Simplification in the acquisition system allows increasing the robustness and the sampling frequency of a motor drive system. Frequency domain multiplexing (FDM) allows reducing the number of signals to be digitized in vector control, simplifying the analog-to-digital system in a motor drive. Nonetheless, the required demultiplexing process is still an open question. This paper proposes a simple demultiplexing technique based on synchronous current sampling. The triangular carrier used in modulation and the resolver excitation signal are synchronized, so that the valley of the carrier happens when the resolver outputs are equal to zero. Thus, the demultiplexed current signals are equal to the samples obtained through synchronous current sampling, eliminating the harmonics in the current signals. The estimated current signals and an angle tracking observer are used to estimate the angular position without the previous demultiplexing of the resolver output signals. Simulation and experimental results show that the demultiplexing process has high accuracy, rejecting the current harmonics and gives a good estimation of the angular position.
{"title":"Simplification of the Acquisition System for Sensored Vector Control using Resolver Sensor based on FDM and Current Synchronous Sampling","authors":"R. García, J. Pinto, I. S. Ono, Vitoria dos Santos Fahed, M. Brito","doi":"10.1109/SPEC.2018.8635967","DOIUrl":"https://doi.org/10.1109/SPEC.2018.8635967","url":null,"abstract":"Simplification in the acquisition system allows increasing the robustness and the sampling frequency of a motor drive system. Frequency domain multiplexing (FDM) allows reducing the number of signals to be digitized in vector control, simplifying the analog-to-digital system in a motor drive. Nonetheless, the required demultiplexing process is still an open question. This paper proposes a simple demultiplexing technique based on synchronous current sampling. The triangular carrier used in modulation and the resolver excitation signal are synchronized, so that the valley of the carrier happens when the resolver outputs are equal to zero. Thus, the demultiplexed current signals are equal to the samples obtained through synchronous current sampling, eliminating the harmonics in the current signals. The estimated current signals and an angle tracking observer are used to estimate the angular position without the previous demultiplexing of the resolver output signals. Simulation and experimental results show that the demultiplexing process has high accuracy, rejecting the current harmonics and gives a good estimation of the angular position.","PeriodicalId":335893,"journal":{"name":"2018 IEEE 4th Southern Power Electronics Conference (SPEC)","volume":"297 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114441942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-01DOI: 10.1109/SPEC.2018.8636023
Hongchang Li, Shuxin Chen, Jingyang Fang, Yi Tang
The receiver-to-transmitter communication in a wireless power transfer (WPT) system plays an important role in the closed-loop control. Existing methods for the communication use separate modules or additional power components connected with the resonant tank or load. Therefore, these methods suffer from low reliabilities, high costs, or large disturbances on power transfer. To overcome these disadvantages, this paper proposes a synchronous rectification-based phase shift keying method for WPT systems. The method is to modulate the phase difference between the rectifier input voltage and the receiver resonant current and demodulate the reflected phase difference between the inverter output voltage and the transmitter resonant current. The disturbance on power transfer caused by the modulation is numerically analyzed. Two encoding schemes, namely the binary encoding and the pulse frequency/width encoding are suggested for digital and analog data transfer, respectively. The maximum data rate, the highest pulse frequency, and the narrowest pulse width are derived based on the system dynamical characteristics. Experimental results are given to verify the method and analysis.
{"title":"Synchronous Rectification-Based Phase Shift Keying Communication for Wireless Power Transfer Systems","authors":"Hongchang Li, Shuxin Chen, Jingyang Fang, Yi Tang","doi":"10.1109/SPEC.2018.8636023","DOIUrl":"https://doi.org/10.1109/SPEC.2018.8636023","url":null,"abstract":"The receiver-to-transmitter communication in a wireless power transfer (WPT) system plays an important role in the closed-loop control. Existing methods for the communication use separate modules or additional power components connected with the resonant tank or load. Therefore, these methods suffer from low reliabilities, high costs, or large disturbances on power transfer. To overcome these disadvantages, this paper proposes a synchronous rectification-based phase shift keying method for WPT systems. The method is to modulate the phase difference between the rectifier input voltage and the receiver resonant current and demodulate the reflected phase difference between the inverter output voltage and the transmitter resonant current. The disturbance on power transfer caused by the modulation is numerically analyzed. Two encoding schemes, namely the binary encoding and the pulse frequency/width encoding are suggested for digital and analog data transfer, respectively. The maximum data rate, the highest pulse frequency, and the narrowest pulse width are derived based on the system dynamical characteristics. Experimental results are given to verify the method and analysis.","PeriodicalId":335893,"journal":{"name":"2018 IEEE 4th Southern Power Electronics Conference (SPEC)","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123168563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-01DOI: 10.1109/SPEC.2018.8635891
B. Nguyen, Jaspreet Singh, Xinan Zhang, Wen-Zhuang Jiang, L. Koh, Peng Wang
This paper proposes a design and control method for double sided LCC compensation network based wireless charging to obtain both constant voltage (CV) and multiple constant current (CC) characteristics which is suitable for stationary charging system without the need of additional electronic components requirement while maintaining input zero phase angle (ZPA) condition for a wide range of load variations. Proper control strategies are also presented to realize soft switching of power switches. The validity of the proposed concept is demonstrated by both theoretical analysis and computer simulations. Experimental results verify the feasibility of the proposed system.
{"title":"Design and Control for ZVS Constant Current and Constant Voltage Wireless Charging Systems","authors":"B. Nguyen, Jaspreet Singh, Xinan Zhang, Wen-Zhuang Jiang, L. Koh, Peng Wang","doi":"10.1109/SPEC.2018.8635891","DOIUrl":"https://doi.org/10.1109/SPEC.2018.8635891","url":null,"abstract":"This paper proposes a design and control method for double sided LCC compensation network based wireless charging to obtain both constant voltage (CV) and multiple constant current (CC) characteristics which is suitable for stationary charging system without the need of additional electronic components requirement while maintaining input zero phase angle (ZPA) condition for a wide range of load variations. Proper control strategies are also presented to realize soft switching of power switches. The validity of the proposed concept is demonstrated by both theoretical analysis and computer simulations. Experimental results verify the feasibility of the proposed system.","PeriodicalId":335893,"journal":{"name":"2018 IEEE 4th Southern Power Electronics Conference (SPEC)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123535957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-01DOI: 10.1109/SPEC.2018.8635982
Jian Liang, Yao Sun, M. Su, Sijie Ning, Min Zhou, Hanbing Dan, Guo Xu
A method based on optimal control is proposed to reduce the commutation torque ripple of brushless dc motors (BLDCMs) in this paper. The theoretical background on optimal control and its design process when applied to BLDCM for commutation torque ripple reduction are given. According to the proposed method, the optimal switching state is selected and applied in the commutation period directly, which makes the non-commutated phase currents stable. Therefore, the commutation torque ripple of the BLDCM is reduced. Simulation results show the effectiveness of the proposed strategy in both high-speed and low-speed conditions as compared to that of the conventional control method.
{"title":"Commutation Torque Ripple Reduction for Brushless DC Motors Based on Optimal Control","authors":"Jian Liang, Yao Sun, M. Su, Sijie Ning, Min Zhou, Hanbing Dan, Guo Xu","doi":"10.1109/SPEC.2018.8635982","DOIUrl":"https://doi.org/10.1109/SPEC.2018.8635982","url":null,"abstract":"A method based on optimal control is proposed to reduce the commutation torque ripple of brushless dc motors (BLDCMs) in this paper. The theoretical background on optimal control and its design process when applied to BLDCM for commutation torque ripple reduction are given. According to the proposed method, the optimal switching state is selected and applied in the commutation period directly, which makes the non-commutated phase currents stable. Therefore, the commutation torque ripple of the BLDCM is reduced. Simulation results show the effectiveness of the proposed strategy in both high-speed and low-speed conditions as compared to that of the conventional control method.","PeriodicalId":335893,"journal":{"name":"2018 IEEE 4th Southern Power Electronics Conference (SPEC)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123672671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-01DOI: 10.1109/SPEC.2018.8636011
Yue Zhang, Chengcheng Yao, Zhongjing Wang, Huanyu Chen, Xiaoteng He, Xuan Zhang, He Li, Jin Wang
This paper presents discussions on the design of Semiconductor-based galvanic isolation (SGI)-based vehicle on-board battery chargers. SGI is a paradigm shift compared to traditional transformer-based solutions by using switched capacitor circuits to realize galvanic isolation. Two major SGI-based battery charger topologies are compared, and a two-stage Totem-pole + SGI dc/dc solution is selected due to higher efficiency. Based on the topology, the touch current (TC) issue is modelled and analyzed, and a buck-boost-based active compensation circuit is proposed with local sensing and control. At last, a 2-kW SGI charger is prototyped and tested, and the efficiency of the dc/dc stage maintains above 98%. With the proposed touch current compensation circuit, the charger meets the safety standards by passing the TC test.
{"title":"Development of a WBG-based Transformerless Electric Vehicle Charger with Semiconductor Isolation","authors":"Yue Zhang, Chengcheng Yao, Zhongjing Wang, Huanyu Chen, Xiaoteng He, Xuan Zhang, He Li, Jin Wang","doi":"10.1109/SPEC.2018.8636011","DOIUrl":"https://doi.org/10.1109/SPEC.2018.8636011","url":null,"abstract":"This paper presents discussions on the design of Semiconductor-based galvanic isolation (SGI)-based vehicle on-board battery chargers. SGI is a paradigm shift compared to traditional transformer-based solutions by using switched capacitor circuits to realize galvanic isolation. Two major SGI-based battery charger topologies are compared, and a two-stage Totem-pole + SGI dc/dc solution is selected due to higher efficiency. Based on the topology, the touch current (TC) issue is modelled and analyzed, and a buck-boost-based active compensation circuit is proposed with local sensing and control. At last, a 2-kW SGI charger is prototyped and tested, and the efficiency of the dc/dc stage maintains above 98%. With the proposed touch current compensation circuit, the charger meets the safety standards by passing the TC test.","PeriodicalId":335893,"journal":{"name":"2018 IEEE 4th Southern Power Electronics Conference (SPEC)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122388442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-01DOI: 10.1109/SPEC.2018.8636057
James Xian, C. Baguley, U. Madawala
Increasingly, it is desired to operate electric fence energizers at higher power levels. This can be achieved by applying higher voltage output pulses from an electric fence energizer onto fence lines. However, and to comply with safety standards, this necessitates an increased level of voltage isolation between input and output parts of a mains-supplied electric fence energizer circuit. Therefore, low cost techniques to achieve high voltage isolation are required. Accordingly, this paper reports such a technique, based on integrating a contactless capacitive power transfer, CPT, circuit into the capacitor charging part of an electric fence energizer. Through compensation, reactive power drawn by the CPT circuit can be reduced, while assuring circuit operation as a current source. This is ideal for capacitor charging purposes, and energy transfer through appropriately separated CPT electrodes allows for high voltage isolation. The proposed CPT circuit is modelled. The results of modelling verify performance.
{"title":"A Wireless Power Transfer System for Electric Fence Energizers","authors":"James Xian, C. Baguley, U. Madawala","doi":"10.1109/SPEC.2018.8636057","DOIUrl":"https://doi.org/10.1109/SPEC.2018.8636057","url":null,"abstract":"Increasingly, it is desired to operate electric fence energizers at higher power levels. This can be achieved by applying higher voltage output pulses from an electric fence energizer onto fence lines. However, and to comply with safety standards, this necessitates an increased level of voltage isolation between input and output parts of a mains-supplied electric fence energizer circuit. Therefore, low cost techniques to achieve high voltage isolation are required. Accordingly, this paper reports such a technique, based on integrating a contactless capacitive power transfer, CPT, circuit into the capacitor charging part of an electric fence energizer. Through compensation, reactive power drawn by the CPT circuit can be reduced, while assuring circuit operation as a current source. This is ideal for capacitor charging purposes, and energy transfer through appropriately separated CPT electrodes allows for high voltage isolation. The proposed CPT circuit is modelled. The results of modelling verify performance.","PeriodicalId":335893,"journal":{"name":"2018 IEEE 4th Southern Power Electronics Conference (SPEC)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124759726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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