With the development of DC distribution technology, electric vehicles and renewable energy will be more efficient access to the grid. In this paper, a model of power supply capability evaluation is proposed, which takes the electric vehicle chargingswapping-storage integrated station and AC/DC hybrid distribution network into account. Firstly, the battery charging station model is built based on the driving behavior characteristics of electric vehicle fast charging users, and then the model of battery swapping station is established combined with urban road traffic model. Finally, the model of electric vehicle charging-swapping-storage integrated station is completed by combining the model of energy storage station. In the AC/DC hybrid distribution network with wind turbine, photovoltaic and integrated station, a power supply capability evaluation model is established. The model is a nonlinear nonconvex mixed integer programming problem, which could be transformed into a mixed integer second-order cone convex optimization problem. The model could be efficiently solved by commercial solver by using linearization and second-order cone relaxation techniques. Taking the modified IEEE33 test system as an example, the effectiveness and rationality of the proposed model are verified by combining with the actual road traffic situation in a certain area.
{"title":"Power supply capability evaluation of AC/DC hybrid distribution network considering charging-swapping-storage integrated station","authors":"H. Yuan","doi":"10.1049/icp.2021.2584","DOIUrl":"https://doi.org/10.1049/icp.2021.2584","url":null,"abstract":"With the development of DC distribution technology, electric vehicles and renewable energy will be more efficient access to the grid. In this paper, a model of power supply capability evaluation is proposed, which takes the electric vehicle chargingswapping-storage integrated station and AC/DC hybrid distribution network into account. Firstly, the battery charging station model is built based on the driving behavior characteristics of electric vehicle fast charging users, and then the model of battery swapping station is established combined with urban road traffic model. Finally, the model of electric vehicle charging-swapping-storage integrated station is completed by combining the model of energy storage station. In the AC/DC hybrid distribution network with wind turbine, photovoltaic and integrated station, a power supply capability evaluation model is established. The model is a nonlinear nonconvex mixed integer programming problem, which could be transformed into a mixed integer second-order cone convex optimization problem. The model could be efficiently solved by commercial solver by using linearization and second-order cone relaxation techniques. Taking the modified IEEE33 test system as an example, the effectiveness and rationality of the proposed model are verified by combining with the actual road traffic situation in a certain area.","PeriodicalId":242596,"journal":{"name":"2021 Annual Meeting of CSEE Study Committee of HVDC and Power Electronics (HVDC 2021)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127660167","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}
Parasitic capacitance is an important parasitic parameter of high-frequency transformer. It is the common-mode coupling channel between the primary and secondary sides of the transformer. This paper analyzes several types of typical transformer parasitic capacitance models and introduces the most suitable one for common-mode analysis. In order to determine the specific parameter values of the model, this article proposes a calculation method to calculate parasitic capacitance. The modelling and calculation are verified by measurements on two sample transformers.
{"title":"Calculation and modelling of transformer parasitic capacitance","authors":"Wenbo Guo, J. Yang, R. Li","doi":"10.1049/icp.2021.2589","DOIUrl":"https://doi.org/10.1049/icp.2021.2589","url":null,"abstract":"Parasitic capacitance is an important parasitic parameter of high-frequency transformer. It is the common-mode coupling channel between the primary and secondary sides of the transformer. This paper analyzes several types of typical transformer parasitic capacitance models and introduces the most suitable one for common-mode analysis. In order to determine the specific parameter values of the model, this article proposes a calculation method to calculate parasitic capacitance. The modelling and calculation are verified by measurements on two sample transformers.","PeriodicalId":242596,"journal":{"name":"2021 Annual Meeting of CSEE Study Committee of HVDC and Power Electronics (HVDC 2021)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114575057","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}
X. Sun, R. Bai, F. Zhuo, B. Zhao, Y. Lou, Q. Liu, X. Wang
Integrated gate commutator thyristor (IGCT) has the advantages of low on-state loss and strong forward current capability, and has the potential for further development. It is suitable for the application of modular multilevel converter (MMC). In this paper, clamping loss of IGCT-based MMC is evaluated. Firstly, the loss caused by various switching behaviours is analysed. The clamping loss caused by IGCT turning-on and turning-off under different current is measured by setting up an experimental circuit. Finally, the clamp loss in specific parameters of MMC is analysed by means of mean equivalent method. The analysis shows that the clamp loss accounts for about 5% of the total loss of the module.
{"title":"Measurement and analysis of clamp circuit loss of IGCT-MMC sub-module","authors":"X. Sun, R. Bai, F. Zhuo, B. Zhao, Y. Lou, Q. Liu, X. Wang","doi":"10.1049/icp.2021.2595","DOIUrl":"https://doi.org/10.1049/icp.2021.2595","url":null,"abstract":"Integrated gate commutator thyristor (IGCT) has the advantages of low on-state loss and strong forward current capability, and has the potential for further development. It is suitable for the application of modular multilevel converter (MMC). In this paper, clamping loss of IGCT-based MMC is evaluated. Firstly, the loss caused by various switching behaviours is analysed. The clamping loss caused by IGCT turning-on and turning-off under different current is measured by setting up an experimental circuit. Finally, the clamp loss in specific parameters of MMC is analysed by means of mean equivalent method. The analysis shows that the clamp loss accounts for about 5% of the total loss of the module.","PeriodicalId":242596,"journal":{"name":"2021 Annual Meeting of CSEE Study Committee of HVDC and Power Electronics (HVDC 2021)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128709449","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}
The development of DC power grids requires DC circuit breaker(DCCB) to have higher breaking capacity. As a key component of DCCB, the withstand voltage and breaking capacity of power electronic devices affect the structure and cost of DCCB. Therefore, it is necessary to upgrade power electronic devices to improve the breaking capability of DCCB and reduce costs. Integrated gate commutated thyristor (IGCT) has great advantages in the application of DCCB due to its inherent high inrush current capacity and low on-state loss. This article introduces a novel IGCT used in DCCB. It is based on the existing 6-inch 4.5kV GCT chip and shell structure. After designing a new gate unit and optimizing the turn-off circuit, it effectively improves the turn-off capability of the device. In the DC circuit breaker application topology, the device has a turn-off capability of 15kA at 2400V. This new device is expected to further increase the breaking capability of DCCB in the future.
{"title":"Research on characteristics of 6-inch IGCT with 15kA turn-off capability in DC circuit breaker","authors":"P. Zou, F. Chen, H. Zeng, X. Pan, Y. Chen, Y. Sun","doi":"10.1049/icp.2021.2551","DOIUrl":"https://doi.org/10.1049/icp.2021.2551","url":null,"abstract":"The development of DC power grids requires DC circuit breaker(DCCB) to have higher breaking capacity. As a key component of DCCB, the withstand voltage and breaking capacity of power electronic devices affect the structure and cost of DCCB. Therefore, it is necessary to upgrade power electronic devices to improve the breaking capability of DCCB and reduce costs. Integrated gate commutated thyristor (IGCT) has great advantages in the application of DCCB due to its inherent high inrush current capacity and low on-state loss. This article introduces a novel IGCT used in DCCB. It is based on the existing 6-inch 4.5kV GCT chip and shell structure. After designing a new gate unit and optimizing the turn-off circuit, it effectively improves the turn-off capability of the device. In the DC circuit breaker application topology, the device has a turn-off capability of 15kA at 2400V. This new device is expected to further increase the breaking capability of DCCB in the future.","PeriodicalId":242596,"journal":{"name":"2021 Annual Meeting of CSEE Study Committee of HVDC and Power Electronics (HVDC 2021)","volume":"21 11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116374363","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}
C. Tian, J. Zhang, J. Zhou, J. Zang, Z. Li, D. Xi, F. Wang, A. Zhang, L. Liu
The DC transformers (DCTs) can achieve flexible power flow control in the ring-type and meshed-type multi-terminal DC grids with less loss. However, due to the limited power flow control range of the DCTs, the power flow controller (PFC) is expected to boost the system's controllability. Unlike the conventional DCTs, this paper proposes an embedded DC power flow controller (e-DCPFC) formed by a PFC and an input-series-output-parallel (ISOP) DCT. This device has the features of multiple ports and extended bidirectional power flow control capability. The operational principle of the e-DCPFC is analysed in detail. And a modified input voltage sharing (m-IVS) control strategy is proposed in this paper. This control scheme not only maintains the input capacitor voltage balanced of the ISOP structure but also controls the power of the extra ports provided by the e-DCPFC. The feasibility and effectiveness of the proposed topology and control strategy are verified via MATLAB simulation mode.
{"title":"A multiport embedded DC power flow controller for ISOP-DCT","authors":"C. Tian, J. Zhang, J. Zhou, J. Zang, Z. Li, D. Xi, F. Wang, A. Zhang, L. Liu","doi":"10.1049/icp.2021.2555","DOIUrl":"https://doi.org/10.1049/icp.2021.2555","url":null,"abstract":"The DC transformers (DCTs) can achieve flexible power flow control in the ring-type and meshed-type multi-terminal DC grids with less loss. However, due to the limited power flow control range of the DCTs, the power flow controller (PFC) is expected to boost the system's controllability. Unlike the conventional DCTs, this paper proposes an embedded DC power flow controller (e-DCPFC) formed by a PFC and an input-series-output-parallel (ISOP) DCT. This device has the features of multiple ports and extended bidirectional power flow control capability. The operational principle of the e-DCPFC is analysed in detail. And a modified input voltage sharing (m-IVS) control strategy is proposed in this paper. This control scheme not only maintains the input capacitor voltage balanced of the ISOP structure but also controls the power of the extra ports provided by the e-DCPFC. The feasibility and effectiveness of the proposed topology and control strategy are verified via MATLAB simulation mode.","PeriodicalId":242596,"journal":{"name":"2021 Annual Meeting of CSEE Study Committee of HVDC and Power Electronics (HVDC 2021)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114365440","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}
Commutation failure is one of the most common faults on the inverter side of HVDC transmission system. Rapid and accurate discrimination of commutation failure is the premise of resisting commutation failure. In this paper, a method for discriminating HVDC commutation failure based on valve voltage and valve current is proposed. According to the process and development of commutation failure, combined with the two waveform information of valve voltage and valve current, the most direct information characteristics of commutation failure are extracted for discrimination. Compared with the discrimination method of single use of converter valve voltage or converter valve current, this method not only accurately discriminates the commutation failure, but also improves the discrimination speed and shortens the discrimination time. Taking CIGRE HVDC benchmark model as simulation example, the logic module of HVDC commutation failure discrimination method based on valve voltage and valve current is built in PSCAD/EMTDC to verify the effectiveness of the proposed method.
{"title":"Discrimination method of HVDC commutation failure based on valve voltage and valve current","authors":"Z. Fan, L. Zhu, X. Wei, D. Liu","doi":"10.1049/icp.2021.2559","DOIUrl":"https://doi.org/10.1049/icp.2021.2559","url":null,"abstract":"Commutation failure is one of the most common faults on the inverter side of HVDC transmission system. Rapid and accurate discrimination of commutation failure is the premise of resisting commutation failure. In this paper, a method for discriminating HVDC commutation failure based on valve voltage and valve current is proposed. According to the process and development of commutation failure, combined with the two waveform information of valve voltage and valve current, the most direct information characteristics of commutation failure are extracted for discrimination. Compared with the discrimination method of single use of converter valve voltage or converter valve current, this method not only accurately discriminates the commutation failure, but also improves the discrimination speed and shortens the discrimination time. Taking CIGRE HVDC benchmark model as simulation example, the logic module of HVDC commutation failure discrimination method based on valve voltage and valve current is built in PSCAD/EMTDC to verify the effectiveness of the proposed method.","PeriodicalId":242596,"journal":{"name":"2021 Annual Meeting of CSEE Study Committee of HVDC and Power Electronics (HVDC 2021)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125601931","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}
In the subway traction power supply system, it is necessary to detect the line state and confirm that there is no short circuit on the line before closing the feeder circuit breaker. In this paper, the existing rules and principles of line test are summarized, the simulation model of subway traction power supply system and locomotive is established, and the results of line test under various conditions are studied. Aiming at the problems existing in the current line test, a new solution is proposed. Furthermore, by calculating temperature rise of the test resistor, the selection method of the test resistor is given.
{"title":"Research on state monitoring method of subway DC traction power supply line","authors":"M. Xia, Y. Huang, Y. Zhou, W. Shuo, Y. Bing","doi":"10.1049/icp.2021.2565","DOIUrl":"https://doi.org/10.1049/icp.2021.2565","url":null,"abstract":"In the subway traction power supply system, it is necessary to detect the line state and confirm that there is no short circuit on the line before closing the feeder circuit breaker. In this paper, the existing rules and principles of line test are summarized, the simulation model of subway traction power supply system and locomotive is established, and the results of line test under various conditions are studied. Aiming at the problems existing in the current line test, a new solution is proposed. Furthermore, by calculating temperature rise of the test resistor, the selection method of the test resistor is given.","PeriodicalId":242596,"journal":{"name":"2021 Annual Meeting of CSEE Study Committee of HVDC and Power Electronics (HVDC 2021)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128110360","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}
In recent years, many high-frequency resonance (HFR) accidents have occurred in high-voltage direct current transmission (HVDC) system based on modular multilevel converter (MMC), which seriously threaten the stable operation of the power system. This paper studies the optimized suppression strategy for HFR of MMC-HVDC System. Firstly, the AC-side smallsignal impedance of MMC is modelled by the harmonic linearization method, which has taken into the consideration of current control loop, power control loop and phase-locked loop (PLL), and then the effect of each control loop on the impedance characteristics of MMC is analysed. Then, aiming at the shortcomings of existing high frequency resonance suppression strategies, an optimized suppression strategy based on voltage feedforward optimization and power control loop optimization is proposed, which reduces the resonance risk in lower frequency bands compare to the existing suppression strategies. Finally, the effectiveness of the optimized suppression strategy is verified by time-domain simulation.
{"title":"Research on optimized suppression strategy for high frequency resonance of MMC-HVDC system","authors":"Q. Huang, L. Lin, C. Wei","doi":"10.1049/icp.2021.2564","DOIUrl":"https://doi.org/10.1049/icp.2021.2564","url":null,"abstract":"In recent years, many high-frequency resonance (HFR) accidents have occurred in high-voltage direct current transmission (HVDC) system based on modular multilevel converter (MMC), which seriously threaten the stable operation of the power system. This paper studies the optimized suppression strategy for HFR of MMC-HVDC System. Firstly, the AC-side smallsignal impedance of MMC is modelled by the harmonic linearization method, which has taken into the consideration of current control loop, power control loop and phase-locked loop (PLL), and then the effect of each control loop on the impedance characteristics of MMC is analysed. Then, aiming at the shortcomings of existing high frequency resonance suppression strategies, an optimized suppression strategy based on voltage feedforward optimization and power control loop optimization is proposed, which reduces the resonance risk in lower frequency bands compare to the existing suppression strategies. Finally, the effectiveness of the optimized suppression strategy is verified by time-domain simulation.","PeriodicalId":242596,"journal":{"name":"2021 Annual Meeting of CSEE Study Committee of HVDC and Power Electronics (HVDC 2021)","volume":"80 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125886124","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}
High Voltage Direct Current(HVDC) transmission projects has been playing crucial role in China Southern Power Grid(CSG). These projects transmit the numerous hydro electricity from Yunnan to Guangdong and Guangxi. Keeping these HVDC projects stabilized operating is important to the whole power grid. Different from Alternate Current(AC) transmission projects, 78% of debugging and checking work for HVDC devices is proceeding before being service as estimated, the commission work actually. The Lugaozhao HVDC project is ±500kV three-terminal HVDC project, which is updated from Gaozhao HVDC project. The multi-terminal project keeps operating normally in the following year after well designed field commission. The paper analyzed the rationality of field commission for multi-terminal HVDC project through the principles, contents and unexpected action in commission.
{"title":"Research on the rationalization of field commissioning for multi-terminal HVDC projects-taking lugaozhao HVDC project for example","authors":"S. Yang, S. Wanli, H. Cong, Z. Yan, Y. Xuefei","doi":"10.1049/icp.2021.2591","DOIUrl":"https://doi.org/10.1049/icp.2021.2591","url":null,"abstract":"High Voltage Direct Current(HVDC) transmission projects has been playing crucial role in China Southern Power Grid(CSG). These projects transmit the numerous hydro electricity from Yunnan to Guangdong and Guangxi. Keeping these HVDC projects stabilized operating is important to the whole power grid. Different from Alternate Current(AC) transmission projects, 78% of debugging and checking work for HVDC devices is proceeding before being service as estimated, the commission work actually. The Lugaozhao HVDC project is ±500kV three-terminal HVDC project, which is updated from Gaozhao HVDC project. The multi-terminal project keeps operating normally in the following year after well designed field commission. The paper analyzed the rationality of field commission for multi-terminal HVDC project through the principles, contents and unexpected action in commission.","PeriodicalId":242596,"journal":{"name":"2021 Annual Meeting of CSEE Study Committee of HVDC and Power Electronics (HVDC 2021)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122195121","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}
There are many control strategies for Vienna rectifiers, but most of them are carried out when the power grid is balanced. In the case of unbalanced power grids, this paper proposes a deadbeat predictive direct power control to reduce the ripple problem of negative sequence current and active power. The strategy meets the minimum power tracking error as the control target to calculate the desired AC side voltage vector, and introduces space vector pulse width modulation to form a closed loop control system. Under unbalanced grid conditions, this strategy can also effectively extract the positive and negative sequence components of the grid voltage and current to form power compensation to suppress the negative sequence components of the current, thereby reducing the current harmonic content. And carry the Vienna rectifier simulation on MATLAB/Simulink for verification.
{"title":"Deadbeat prediction direct power control of Vienna rectifier under unbalanced three-phase Voltage","authors":"X. Wen kai, X. Hui hui, G. Qiang, C. Lan","doi":"10.1049/icp.2021.2531","DOIUrl":"https://doi.org/10.1049/icp.2021.2531","url":null,"abstract":"There are many control strategies for Vienna rectifiers, but most of them are carried out when the power grid is balanced. In the case of unbalanced power grids, this paper proposes a deadbeat predictive direct power control to reduce the ripple problem of negative sequence current and active power. The strategy meets the minimum power tracking error as the control target to calculate the desired AC side voltage vector, and introduces space vector pulse width modulation to form a closed loop control system. Under unbalanced grid conditions, this strategy can also effectively extract the positive and negative sequence components of the grid voltage and current to form power compensation to suppress the negative sequence components of the current, thereby reducing the current harmonic content. And carry the Vienna rectifier simulation on MATLAB/Simulink for verification.","PeriodicalId":242596,"journal":{"name":"2021 Annual Meeting of CSEE Study Committee of HVDC and Power Electronics (HVDC 2021)","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123249492","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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