Pub Date : 2016-03-20DOI: 10.1109/APEC.2016.7468066
S. Madhusoodhanan, K. Mainali, A. Tripathi, K. Vechalapu, S. Bhattacharya
High speed variable frequency motor drives are required for marine applications, compressors for oil and gas industries, wind energy generation systems etc. Traditionally, low voltage high speed motor drives are used in such applications. This results in large currents at high power levels leading to large copper loss in the motor winding. Therefore, medium voltage (MV) drives are being considered. The silicon (Si) based MV drives need gears to increase the speed due to low switching frequency operation of Si devices in the converter. Gears reduce both efficiency and power density. With the development of 10 kV SiC MOSFET, high switching frequency at MV is possible, which has enabled the scope of high power density MV direct drive variable speed controlled motors. In this paper, the design of a three-phase, 2-level, ≥ 2.3 kV MV, high frequency converter based on 10 kV SiC MOSEFT is explained. Performance analysis is presented along with experimental demonstration.
高速变频电机驱动需要用于船舶应用，石油和天然气工业的压缩机，风力发电系统等。传统上，低压高速电机驱动器用于此类应用。这导致在高功率水平下产生大电流，导致电机绕组中的大铜损耗。因此，正在考虑中压(MV)驱动器。基于硅(Si)的中压驱动器需要齿轮来提高速度，因为转换器中硅器件的开关频率较低。齿轮降低了效率和功率密度。随着10 kV SiC MOSFET的发展，使得MV高开关频率成为可能，从而实现了高功率密度MV直接驱动变速控制电机的范围。本文介绍了一种基于10 kV SiC MOSEFT的三相2电平、≥2.3 kV MV高频变频器的设计。并进行了性能分析和实验验证。
{"title":"Medium voltage (≥ 2.3 kV) high frequency three-phase two-level converter design and demonstration using 10 kV SiC MOSFETs for high speed motor drive applications","authors":"S. Madhusoodhanan, K. Mainali, A. Tripathi, K. Vechalapu, S. Bhattacharya","doi":"10.1109/APEC.2016.7468066","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468066","url":null,"abstract":"High speed variable frequency motor drives are required for marine applications, compressors for oil and gas industries, wind energy generation systems etc. Traditionally, low voltage high speed motor drives are used in such applications. This results in large currents at high power levels leading to large copper loss in the motor winding. Therefore, medium voltage (MV) drives are being considered. The silicon (Si) based MV drives need gears to increase the speed due to low switching frequency operation of Si devices in the converter. Gears reduce both efficiency and power density. With the development of 10 kV SiC MOSFET, high switching frequency at MV is possible, which has enabled the scope of high power density MV direct drive variable speed controlled motors. In this paper, the design of a three-phase, 2-level, ≥ 2.3 kV MV, high frequency converter based on 10 kV SiC MOSEFT is explained. Performance analysis is presented along with experimental demonstration.","PeriodicalId":143091,"journal":{"name":"2016 IEEE Applied Power Electronics Conference and Exposition (APEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134480122","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 : 2016-03-20DOI: 10.1109/APEC.2016.7468093
A. Renjit, F. Guo, Ratnesh K. Sharma
Microgrids with increased penetration of renewables have significant frequency excursions to power generation changes. A straight forward approach to solve this problem is by enhancing the inertia of the system using energy storage (ES). They provide Dynamic Frequency Control (DFC) support to the interconnected Distributed Energy Resources (DERs) in the microgrid. However, the amount of inertial support required from the ES varies based on the type of interconnected DERs, the amount of load change and many other factors. This paper proposes an analytical framework for calculating the inertia required from the ES systems during a generation change. A case study to corroborate the proposed framework for the DFC scheme has also been studied.
{"title":"An analytical framework to design a Dynamic Frequency Control scheme for microgrids using energy storage","authors":"A. Renjit, F. Guo, Ratnesh K. Sharma","doi":"10.1109/APEC.2016.7468093","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468093","url":null,"abstract":"Microgrids with increased penetration of renewables have significant frequency excursions to power generation changes. A straight forward approach to solve this problem is by enhancing the inertia of the system using energy storage (ES). They provide Dynamic Frequency Control (DFC) support to the interconnected Distributed Energy Resources (DERs) in the microgrid. However, the amount of inertial support required from the ES varies based on the type of interconnected DERs, the amount of load change and many other factors. This paper proposes an analytical framework for calculating the inertia required from the ES systems during a generation change. A case study to corroborate the proposed framework for the DFC scheme has also been studied.","PeriodicalId":143091,"journal":{"name":"2016 IEEE Applied Power Electronics Conference and Exposition (APEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131275753","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 : 2016-03-20DOI: 10.1109/APEC.2016.7468153
A. Tripathi, K. Mainali, S. Madhusoodhanan, Akshat Yadav, K. Vechalapu, S. Bhattacharya
This paper presents an Intelligent Medium-voltage Gate Driver (IMGD) for 15kV SiC IGBT and 10kV SiC MOSFET devices. The high voltage-magnitude and high dv/dt(> 30kV/μs) of these MV SiC devices, pose design challenge in form of isolation and EMI. This problem is solved by development of a <; 1pF isolation capacitance power-supply. But due to applied high stress, smaller short-circuit withstand time and the criticality of the application, these devices need to be monitored, well protected, active gate-driven and safely shut-down. This paper presents an EMI hardened IMGD built around a CPLD, sensing and optical interfacing unit. It provides advanced gate-driving, added protection and optically isolated state-monitoring features. The device operating conditions such as module temperature and Vds(on) can be data-logged. They can be used for diagnosis/prognosis purposes such as to predict failure and safely shut-down the system. This paper describes the functionality of different building blocks. The 15kV SiC IGBT has higher second switching slope above its punch-through level which is moderated without increasing losses by using digitally controlled active gate-driving. The shoot-through protection time can be reduced below withstand time by advanced gate driving. Soft turn-on and over-current triggered gate-voltage reduction helps reducing blanking time and quick turn-off reduces the protection response time. In this paper, the IMGD is high side tested at 5kV with device state monitoring on. The active gate-driving is tested at 6kV.
提出了一种适用于15kV SiC IGBT和10kV SiC MOSFET器件的智能中压栅极驱动器(IMGD)。这些中压SiC器件的高电压幅值和高dv/dt(> 30kV/μs)给设计带来了隔离和电磁干扰方面的挑战。这个问题是通过<;1pF隔离电容电源。但由于施加的高应力，更短的短路承受时间和应用的关键性，这些设备需要监控，良好的保护，有源栅极驱动和安全关闭。本文提出了一种基于CPLD、传感和光接口单元的抗电磁干扰IMGD。它提供了先进的栅极驱动，附加保护和光隔离状态监控功能。设备的工作条件，如模块温度和Vds(on)可以数据记录。它们可用于诊断/预测目的，例如预测故障并安全关闭系统。本文描述了不同构建块的功能。15kV SiC IGBT在其击穿电平以上具有更高的第二次开关斜率，通过使用数字控制有源栅极驱动可以在不增加损耗的情况下进行调节。采用先进的浇口驱动，可将穿透保护时间缩短至承受时间以下。软通和过流触发栅极电压降低有助于减少停机时间和快速关断减少保护响应时间。本文在5kV高压下，在设备状态监测的情况下，对IMGD进行了高侧试验。主动栅极驱动在6kV下进行了测试。
{"title":"A MV intelligent gate driver for 15kV SiC IGBT and 10kV SiC MOSFET","authors":"A. Tripathi, K. Mainali, S. Madhusoodhanan, Akshat Yadav, K. Vechalapu, S. Bhattacharya","doi":"10.1109/APEC.2016.7468153","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468153","url":null,"abstract":"This paper presents an Intelligent Medium-voltage Gate Driver (IMGD) for 15kV SiC IGBT and 10kV SiC MOSFET devices. The high voltage-magnitude and high dv/dt(> 30kV/μs) of these MV SiC devices, pose design challenge in form of isolation and EMI. This problem is solved by development of a <; 1pF isolation capacitance power-supply. But due to applied high stress, smaller short-circuit withstand time and the criticality of the application, these devices need to be monitored, well protected, active gate-driven and safely shut-down. This paper presents an EMI hardened IMGD built around a CPLD, sensing and optical interfacing unit. It provides advanced gate-driving, added protection and optically isolated state-monitoring features. The device operating conditions such as module temperature and Vds(on) can be data-logged. They can be used for diagnosis/prognosis purposes such as to predict failure and safely shut-down the system. This paper describes the functionality of different building blocks. The 15kV SiC IGBT has higher second switching slope above its punch-through level which is moderated without increasing losses by using digitally controlled active gate-driving. The shoot-through protection time can be reduced below withstand time by advanced gate driving. Soft turn-on and over-current triggered gate-voltage reduction helps reducing blanking time and quick turn-off reduces the protection response time. In this paper, the IMGD is high side tested at 5kV with device state monitoring on. The active gate-driving is tested at 6kV.","PeriodicalId":143091,"journal":{"name":"2016 IEEE Applied Power Electronics Conference and Exposition (APEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133829750","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 : 2016-03-20DOI: 10.1109/APEC.2016.7468155
Laili Wang, D. Malcolm, Yanfei Liu
This paper presents an integrated power module with the features of high power density and high efficiency. A multi-functional integrated magnetic component is designed. The component has the roles of both the filter inductor and the case of the whole power module. With the assist of finite element analysis (FEA), design and optimization of the proposed inductor are demonstrated. It has higher inductance value than the inductor used in conventional designs. It has bigger coil winding and larger surface area, leading to lower DCR and better thermal performances than plastic packaging. Benefiting from these advantages, the power module constructed based on the inductor can achieve higher efficiency and lower temperature than those based on traditional plastic packaging solutions. Design of the inductor is demonstrated through the combination of analytical and simulation methods. An inductor prototype is built and used in an integrated power module to do experimental tests. Loss breakdown of the power module is executed to show the loss of the magnetic component. The proposed power module shows better performances than the plastic packaging solution.
{"title":"An innovative power module with power-system-in-inductor structure","authors":"Laili Wang, D. Malcolm, Yanfei Liu","doi":"10.1109/APEC.2016.7468155","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468155","url":null,"abstract":"This paper presents an integrated power module with the features of high power density and high efficiency. A multi-functional integrated magnetic component is designed. The component has the roles of both the filter inductor and the case of the whole power module. With the assist of finite element analysis (FEA), design and optimization of the proposed inductor are demonstrated. It has higher inductance value than the inductor used in conventional designs. It has bigger coil winding and larger surface area, leading to lower DCR and better thermal performances than plastic packaging. Benefiting from these advantages, the power module constructed based on the inductor can achieve higher efficiency and lower temperature than those based on traditional plastic packaging solutions. Design of the inductor is demonstrated through the combination of analytical and simulation methods. An inductor prototype is built and used in an integrated power module to do experimental tests. Loss breakdown of the power module is executed to show the loss of the magnetic component. The proposed power module shows better performances than the plastic packaging solution.","PeriodicalId":143091,"journal":{"name":"2016 IEEE Applied Power Electronics Conference and Exposition (APEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124345420","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 : 2016-03-20DOI: 10.1109/APEC.2016.7468288
M. Ando, K. Wada
Recently, high-speed switching circuits using SiC and GaN power devices have been developed for realizing higher efficiency. Stray inductance caused by the wiring structure between a DC capacitor and power devices is one of the most critical parameters for these high-speed switching circuits. In this paper a DC-side stray inductance design procedure for a high-speed switching circuit is presented based on a normalization procedure. The stray inductance is presented not as the absolute value [H] but as the percent value [%] based on the power rating of the converter circuit. By applying the proposed method, the stray inductance can be designed for a circuit depending on the switching time and the voltage and current ratings. To verify the normalization method, experimental results are shown using an all-SiC module at voltage and current ratings of 500 V and 100 A, respectively.
{"title":"A normalization procedure of DC-side stray inductance for high-speed switching circuit","authors":"M. Ando, K. Wada","doi":"10.1109/APEC.2016.7468288","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468288","url":null,"abstract":"Recently, high-speed switching circuits using SiC and GaN power devices have been developed for realizing higher efficiency. Stray inductance caused by the wiring structure between a DC capacitor and power devices is one of the most critical parameters for these high-speed switching circuits. In this paper a DC-side stray inductance design procedure for a high-speed switching circuit is presented based on a normalization procedure. The stray inductance is presented not as the absolute value [H] but as the percent value [%] based on the power rating of the converter circuit. By applying the proposed method, the stray inductance can be designed for a circuit depending on the switching time and the voltage and current ratings. To verify the normalization method, experimental results are shown using an all-SiC module at voltage and current ratings of 500 V and 100 A, respectively.","PeriodicalId":143091,"journal":{"name":"2016 IEEE Applied Power Electronics Conference and Exposition (APEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114777918","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 : 2016-03-20DOI: 10.1109/APEC.2016.7467992
B. Zojer
Normally-on high-voltage (HV) power transistors are usually operated in a series connection with low-voltage (LV) MOSFETs to ensure safe operation. In the widely used cascode configuration (CC) the status of the combined switch is controlled via the MOSFET gate, whereas the alternative direct drive (DD) method controls the gate of the HV switch directly and utilizes the LV transistor as a safety switch only. Both concepts have their respective benefits: CC allows simple standard driving schemes, while DD excels in low switching losses. This paper investigates a third approach: by controlling both HV and LV gates an optimization of switching performance particularly in hard-switched half-bridge applications can be achieved. However, a straight-forward implementation of such a “dual drive” (2D) concept would obviously require a sophisticated driving scheme to allow independent control of both gates. The key idea of this paper is thus the substitution of a separate HV gate driver by a charge pump circuit connected to the LV gate driver. The new concept finally modifies CC by simply adding 3 passive components (resistor, capacitor, diode - “RCD” concept), yet it significantly lowers both losses and voltage stress. In a nutshell, the proposed cascode is able to combine direct drive switching performance with standard driving schemes.
{"title":"A new driving concept for normally-on GaN switches in cascode configuration","authors":"B. Zojer","doi":"10.1109/APEC.2016.7467992","DOIUrl":"https://doi.org/10.1109/APEC.2016.7467992","url":null,"abstract":"Normally-on high-voltage (HV) power transistors are usually operated in a series connection with low-voltage (LV) MOSFETs to ensure safe operation. In the widely used cascode configuration (CC) the status of the combined switch is controlled via the MOSFET gate, whereas the alternative direct drive (DD) method controls the gate of the HV switch directly and utilizes the LV transistor as a safety switch only. Both concepts have their respective benefits: CC allows simple standard driving schemes, while DD excels in low switching losses. This paper investigates a third approach: by controlling both HV and LV gates an optimization of switching performance particularly in hard-switched half-bridge applications can be achieved. However, a straight-forward implementation of such a “dual drive” (2D) concept would obviously require a sophisticated driving scheme to allow independent control of both gates. The key idea of this paper is thus the substitution of a separate HV gate driver by a charge pump circuit connected to the LV gate driver. The new concept finally modifies CC by simply adding 3 passive components (resistor, capacitor, diode - “RCD” concept), yet it significantly lowers both losses and voltage stress. In a nutshell, the proposed cascode is able to combine direct drive switching performance with standard driving schemes.","PeriodicalId":143091,"journal":{"name":"2016 IEEE Applied Power Electronics Conference and Exposition (APEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117334662","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 : 2016-03-20DOI: 10.1109/APEC.2016.7468260
J. Bermingham, G. O'Donovan, Ray Walsh, M. Egan, G. Lightbody, J. Hayes
Magnetic saturation may cause the inductance of a servo motor to deviate from values defined during the design of a drive's control system. Modern servo-drives are equipped with field-weakening strategies that control the trajectory of the motor's current vectors to produce the optimum levels of torque within the defined limit of current and voltage. The objective of this paper is to develop a `plug and play' control scheme to integrate industrial inverters and machines without extensive characterization of the matched set, while operating within the operating specifications of the drive components. In this paper, an approach to torque optimization is presented in which the motor-terminal voltage-vector magnitude is regulated at high motor speeds while producing torque-optimizing current-vector commands. This method differs from other field-weakening solutions due to the active control of the voltage vector trajectory on the dq-voltage plane across an extended motor speed range. In a decoupled cascaded control strategy, the voltage-control loops produce current-vector trajectory commands in order to realize the voltage set points. The resulting current vector continuously conforms to the defined voltage and current limits of the servo drive without characterization of magnetic saturation. Results of the successful hardware implementation of the method in an industrial drive are presented.
{"title":"Optimized control of high-performance servo-motor drives in the field-weakening region","authors":"J. Bermingham, G. O'Donovan, Ray Walsh, M. Egan, G. Lightbody, J. Hayes","doi":"10.1109/APEC.2016.7468260","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468260","url":null,"abstract":"Magnetic saturation may cause the inductance of a servo motor to deviate from values defined during the design of a drive's control system. Modern servo-drives are equipped with field-weakening strategies that control the trajectory of the motor's current vectors to produce the optimum levels of torque within the defined limit of current and voltage. The objective of this paper is to develop a `plug and play' control scheme to integrate industrial inverters and machines without extensive characterization of the matched set, while operating within the operating specifications of the drive components. In this paper, an approach to torque optimization is presented in which the motor-terminal voltage-vector magnitude is regulated at high motor speeds while producing torque-optimizing current-vector commands. This method differs from other field-weakening solutions due to the active control of the voltage vector trajectory on the dq-voltage plane across an extended motor speed range. In a decoupled cascaded control strategy, the voltage-control loops produce current-vector trajectory commands in order to realize the voltage set points. The resulting current vector continuously conforms to the defined voltage and current limits of the servo drive without characterization of magnetic saturation. Results of the successful hardware implementation of the method in an industrial drive are presented.","PeriodicalId":143091,"journal":{"name":"2016 IEEE Applied Power Electronics Conference and Exposition (APEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122141477","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 : 2016-03-20DOI: 10.1109/APEC.2016.7467998
H. Sarnago, Óscar Lucía, J. Burdío
Induction heating is an efficient and high performance heating method which already has a significant market penetration and economic impact due to its benefits inherent to contactless energy transfer systems such as quickness, cleanness, and safety. In order to improve the efficiency and performance of modern induction heating systems, this paper presents a multiple-output boost resonant inverter. The proposed topologies significantly improves the converter efficiency due to the reduced current level while being able to supply several induction loads. Consequently, a high-performance and cost-effective implementation is achieved. The proposed converter has been tested through a 3.6-kW dual-output prototype, proving the feasibility of this proposal.
{"title":"Multiple-output boost resonant inverter for high efficiency and cost-effective induction heating applications","authors":"H. Sarnago, Óscar Lucía, J. Burdío","doi":"10.1109/APEC.2016.7467998","DOIUrl":"https://doi.org/10.1109/APEC.2016.7467998","url":null,"abstract":"Induction heating is an efficient and high performance heating method which already has a significant market penetration and economic impact due to its benefits inherent to contactless energy transfer systems such as quickness, cleanness, and safety. In order to improve the efficiency and performance of modern induction heating systems, this paper presents a multiple-output boost resonant inverter. The proposed topologies significantly improves the converter efficiency due to the reduced current level while being able to supply several induction loads. Consequently, a high-performance and cost-effective implementation is achieved. The proposed converter has been tested through a 3.6-kW dual-output prototype, proving the feasibility of this proposal.","PeriodicalId":143091,"journal":{"name":"2016 IEEE Applied Power Electronics Conference and Exposition (APEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124102913","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 : 2016-03-20DOI: 10.1109/APEC.2016.7468070
Jiangchao Qin, S. Debnath, M. Saeedifard
The modular multilevel converter (MMC) has become one of the most promising converter technologies for medium/high-power applications, specifically for high-voltage direct current (HVDC) transmission systems. One of the technical challenges associated with the operation and control of the MMC-based system is to precharge the submodule (SM) capacitors to their nominal voltages during the startup process. In this paper, considering various SM circuits, a general precharging strategy is proposed for the MMC-based systems under ac-and dc-side startup conditions. The proposed startup method does not require any additional feedback control loop, extra measurements, and/or auxiliary power supplies. Based on the developed startup method, the charging current is controllable by adjusting the changing rate of the number of blocked and bypassed SM capacitors. Performance of the proposed strategy for various MMCs is evaluated based on time-domain simulation studies in the PSCAD/EMTDC software environment.
{"title":"Precharging strategy for soft startup process of modular multilevel converters based on various SM circuits","authors":"Jiangchao Qin, S. Debnath, M. Saeedifard","doi":"10.1109/APEC.2016.7468070","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468070","url":null,"abstract":"The modular multilevel converter (MMC) has become one of the most promising converter technologies for medium/high-power applications, specifically for high-voltage direct current (HVDC) transmission systems. One of the technical challenges associated with the operation and control of the MMC-based system is to precharge the submodule (SM) capacitors to their nominal voltages during the startup process. In this paper, considering various SM circuits, a general precharging strategy is proposed for the MMC-based systems under ac-and dc-side startup conditions. The proposed startup method does not require any additional feedback control loop, extra measurements, and/or auxiliary power supplies. Based on the developed startup method, the charging current is controllable by adjusting the changing rate of the number of blocked and bypassed SM capacitors. Performance of the proposed strategy for various MMCs is evaluated based on time-domain simulation studies in the PSCAD/EMTDC software environment.","PeriodicalId":143091,"journal":{"name":"2016 IEEE Applied Power Electronics Conference and Exposition (APEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125844699","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 : 2016-03-20DOI: 10.1109/APEC.2016.7467952
Xing Li, Hua Lin
To investigate the instability issues of three-phase voltage source converters (VSCs) connected to a weak grid, this paper develops a modeling method based on the harmonic-balance approach. The nonlinear coordinate transformation in the control system would generate two sideband components. If the grid is not strong while the bandwidth of phase-locked loop (PLL) is high enough, the sideband components would be coupled, and both of them have influence on system stability, neither of them could be neglected. Hence, there would be two feedback loops of grid-current representing two sideband frequencies. Taking this effect into account, the multifrequency small-signal model is proposed. It is further demonstrated that the sum of the two grid-current loop gains determines the stability and transient performance. Simulations and experimental results were conducted to validate the analysis.
{"title":"Multifrequency small-signal model of voltage source converters connected to a weak grid for stability analysis","authors":"Xing Li, Hua Lin","doi":"10.1109/APEC.2016.7467952","DOIUrl":"https://doi.org/10.1109/APEC.2016.7467952","url":null,"abstract":"To investigate the instability issues of three-phase voltage source converters (VSCs) connected to a weak grid, this paper develops a modeling method based on the harmonic-balance approach. The nonlinear coordinate transformation in the control system would generate two sideband components. If the grid is not strong while the bandwidth of phase-locked loop (PLL) is high enough, the sideband components would be coupled, and both of them have influence on system stability, neither of them could be neglected. Hence, there would be two feedback loops of grid-current representing two sideband frequencies. Taking this effect into account, the multifrequency small-signal model is proposed. It is further demonstrated that the sum of the two grid-current loop gains determines the stability and transient performance. Simulations and experimental results were conducted to validate the analysis.","PeriodicalId":143091,"journal":{"name":"2016 IEEE Applied Power Electronics Conference and Exposition (APEC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124968695","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：