Pub Date : 2016-03-20DOI: 10.1109/APEC.2016.7468196
Qianlai Zhu, Li Wang, Liqi Zhang, Wensong Yu, A. Huang
An improved bidirectional medium voltage AC-DC converter based on 10kV silicon carbide (SiC) MOSFETs for SST (Solid State Transformer) application is presented in this paper. Avalanche breakdown of the reverse blocking silicon diode and bridge arm shoot-through problems in traditional high voltage bridge-type AC-DC converters are solved. Shoot-through currents are limited to low di/dt events that are readily controlled, allowing zero dead-time operation. The reverse recovery dissipation of the SiC MOSFET is eliminated because no freewheeling current will flow through the body diode. This increases the efficiency as well as the reliability of the SiC MOSFET. Detailed power stage operating principles and energy transfer mechanism are described. A unique customized 10kV SiC MOSFET/JBS diode power module is developed and tested, which further reduces parasitic parameters and simplifies converter wire connection. This topology is therefore a very good choice for median voltage applications.
提出了一种基于10kV碳化硅(SiC) mosfet的改进型双向中压交直流变换器，用于固态变压器(SST)。解决了传统高压桥式交直流变换器中反向阻断硅二极管的雪崩击穿和桥臂穿透问题。射通电流限制在易于控制的低di/dt事件，允许零死区操作。SiC MOSFET的反向恢复耗散被消除，因为没有自由流动的电流将流过主体二极管。这提高了效率以及SiC MOSFET的可靠性。详细介绍了功率级的工作原理和能量传递机理。开发并测试了独特的定制10kV SiC MOSFET/JBS二极管功率模块，进一步降低了寄生参数，简化了转换器接线。因此，这种拓扑结构是中值电压应用的一个很好的选择。
{"title":"Improved medium voltage AC-DC rectifier based on 10kV SiC MOSFET for Solid State Transformer (SST) application","authors":"Qianlai Zhu, Li Wang, Liqi Zhang, Wensong Yu, A. Huang","doi":"10.1109/APEC.2016.7468196","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468196","url":null,"abstract":"An improved bidirectional medium voltage AC-DC converter based on 10kV silicon carbide (SiC) MOSFETs for SST (Solid State Transformer) application is presented in this paper. Avalanche breakdown of the reverse blocking silicon diode and bridge arm shoot-through problems in traditional high voltage bridge-type AC-DC converters are solved. Shoot-through currents are limited to low di/dt events that are readily controlled, allowing zero dead-time operation. The reverse recovery dissipation of the SiC MOSFET is eliminated because no freewheeling current will flow through the body diode. This increases the efficiency as well as the reliability of the SiC MOSFET. Detailed power stage operating principles and energy transfer mechanism are described. A unique customized 10kV SiC MOSFET/JBS diode power module is developed and tested, which further reduces parasitic parameters and simplifies converter wire connection. This topology is therefore a very good choice for median voltage applications.","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":"128811483","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.2016.7468141
A. Rahnamaee, A. Mojab, H. Riazmontazer, S. Mazumder, M. Žefran
This paper presents a soft-switched discontinuous pulse-width pulse-density modulation (PWPDM) scheme to decrease the switching losses of the capacitor-less high-frequency pulsating dc-link (HFPDCL) inverters. The proposed modulation scheme employs both pulse-width modulation (PWM) and pulse-density modulation (PDM) schemes to increase the overall efficiency of the inverter and generate high-quality output line-frequency (LF) Sine waveforms. In order to increase the efficiency of the converter, it decreases the switching requirement of the converter and it also provides soft-switching condition for the output inverter. The performance of the proposed PWPDM scheme is verified using am experimental 2 kW HFPDCL inverter.
{"title":"Soft-switched discontinuous pulse-width pulse-density modulation scheme","authors":"A. Rahnamaee, A. Mojab, H. Riazmontazer, S. Mazumder, M. Žefran","doi":"10.1109/APEC.2016.7468141","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468141","url":null,"abstract":"This paper presents a soft-switched discontinuous pulse-width pulse-density modulation (PWPDM) scheme to decrease the switching losses of the capacitor-less high-frequency pulsating dc-link (HFPDCL) inverters. The proposed modulation scheme employs both pulse-width modulation (PWM) and pulse-density modulation (PDM) schemes to increase the overall efficiency of the inverter and generate high-quality output line-frequency (LF) Sine waveforms. In order to increase the efficiency of the converter, it decreases the switching requirement of the converter and it also provides soft-switching condition for the output inverter. The performance of the proposed PWPDM scheme is verified using am experimental 2 kW HFPDCL inverter.","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":"125507603","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.2016.7468202
Sokchea Am, P. Lefranc, D. Frey, M. Ibrahim
In this article, a design methodology for DC-DC converters with high insulation capabilities (up to 30kV) is proposed. The objective is to provide a power transmission function for IGBT drivers. To achieve this, a DC-DC full-bridge series-series (FB-SS) resonant converter with a high air gap transformer is selected and studied. This high air gap transformer (loosely coupled transformer (k)) is used for a high galvanic insulation system. Some transformer geometries are analyzed and compared for this specific application field. Therefore, in term of coupling coefficient of transformer (k), the analysis and the proposed investigations prove that pot core based transformers are suitable choices. Simulation results are presented and analyzed and experimental works are briefly described. Finally, the comparison between the simulation and experimental results are illustrated to validate the proposed methodology.
{"title":"Design methodology for a high insulation voltage power transmission function for IGBT gate driver","authors":"Sokchea Am, P. Lefranc, D. Frey, M. Ibrahim","doi":"10.1109/APEC.2016.7468202","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468202","url":null,"abstract":"In this article, a design methodology for DC-DC converters with high insulation capabilities (up to 30kV) is proposed. The objective is to provide a power transmission function for IGBT drivers. To achieve this, a DC-DC full-bridge series-series (FB-SS) resonant converter with a high air gap transformer is selected and studied. This high air gap transformer (loosely coupled transformer (k)) is used for a high galvanic insulation system. Some transformer geometries are analyzed and compared for this specific application field. Therefore, in term of coupling coefficient of transformer (k), the analysis and the proposed investigations prove that pot core based transformers are suitable choices. Simulation results are presented and analyzed and experimental works are briefly described. Finally, the comparison between the simulation and experimental results are illustrated to validate the proposed methodology.","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":"123325284","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.2016.7468298
R. Beres, Xiongfei Wang, F. Blaabjerg, C. Bak, H. Matsumori, Toshihisa Shimizu
Inductive components play an important role in filtering the switching harmonics related to the pulse width modulation in voltage source converters. Particularly, the filter reactor on the converter side of the filter is subjected to rectangular excitation which may lead to significant losses in the core, depending on the magnetic material of choice and current ripple specifications. Additionally, shunt or series reactors that exists in LCL or trap filters and which are subjected to sinusoidal excitations have different specifications and requirements. Therefore, the core losses of different magnetic materials adopted in utility grid ac filters have been investigated and measured for both sinusoidal and rectangular excitation, with and without dc bias condition. The core loss information can ensure cost-effective passive filter designs and may avoid trial-error design procedures of the passive components parameters.
{"title":"Evaluation of core loss in magnetic materials employed in utility grid AC filters","authors":"R. Beres, Xiongfei Wang, F. Blaabjerg, C. Bak, H. Matsumori, Toshihisa Shimizu","doi":"10.1109/APEC.2016.7468298","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468298","url":null,"abstract":"Inductive components play an important role in filtering the switching harmonics related to the pulse width modulation in voltage source converters. Particularly, the filter reactor on the converter side of the filter is subjected to rectangular excitation which may lead to significant losses in the core, depending on the magnetic material of choice and current ripple specifications. Additionally, shunt or series reactors that exists in LCL or trap filters and which are subjected to sinusoidal excitations have different specifications and requirements. Therefore, the core losses of different magnetic materials adopted in utility grid ac filters have been investigated and measured for both sinusoidal and rectangular excitation, with and without dc bias condition. The core loss information can ensure cost-effective passive filter designs and may avoid trial-error design procedures of the passive components parameters.","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":"126875242","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.2016.7467973
Stefan Ditze, T. Heckel, M. Mârz
Multi-resonant converters like the CLLLC topology are known for their outstanding efficiency and high power density. Little information has however been published about the influences of secondary side diode junction capacitances on the output characteristics of the resonant converter. This paper presents a detailed analysis of these influences in the inductive working range and reviews practical design considerations of the converter. Therefore, experimental results of an inductive power transfer system, using a CLLLC resonant topology, are compared to theoretical time domain solution, showing significant effects of different semiconductor materials and devices on output power. These effects will be discussed and explained in detail by using measured key waveforms.
{"title":"Influence of the junction capacitance of the secondary rectifier diodes on output characteristics in multi-resonant converters","authors":"Stefan Ditze, T. Heckel, M. Mârz","doi":"10.1109/APEC.2016.7467973","DOIUrl":"https://doi.org/10.1109/APEC.2016.7467973","url":null,"abstract":"Multi-resonant converters like the CLLLC topology are known for their outstanding efficiency and high power density. Little information has however been published about the influences of secondary side diode junction capacitances on the output characteristics of the resonant converter. This paper presents a detailed analysis of these influences in the inductive working range and reviews practical design considerations of the converter. Therefore, experimental results of an inductive power transfer system, using a CLLLC resonant topology, are compared to theoretical time domain solution, showing significant effects of different semiconductor materials and devices on output power. These effects will be discussed and explained in detail by using measured key waveforms.","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":"120930806","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.2016.7467888
Kevin Lenz, Vladan Jerinic, Reiner Hinken
During standard robustness evaluations of a NPC type 2 IGBT power module a non-described effect in a Three Level NPC 2 topology was observed. A full description of that effect can help to protect IGBT power modules in this topology against blow ups and can help in a post mortem analysis to understand the reason for this. With a full understanding of that effect the lifetime of the inverter can be increased and the time and costs for qualification reduced.
{"title":"Investigation of short circuit in a IGBT power module with Three-Level neutral point clamped type 2 (NPC2, T-NPC, mixed voltage) topology","authors":"Kevin Lenz, Vladan Jerinic, Reiner Hinken","doi":"10.1109/APEC.2016.7467888","DOIUrl":"https://doi.org/10.1109/APEC.2016.7467888","url":null,"abstract":"During standard robustness evaluations of a NPC type 2 IGBT power module a non-described effect in a Three Level NPC 2 topology was observed. A full description of that effect can help to protect IGBT power modules in this topology against blow ups and can help in a post mortem analysis to understand the reason for this. With a full understanding of that effect the lifetime of the inverter can be increased and the time and costs for qualification reduced.","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":"116074402","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.2016.7467961
S. Moury, J. Lam, V. Srivastava, R. Church
The energy consumption of the information technology (IT) data centers and servers have been increasing rapidly for the past decade. In order to reduce global warming and conserve depleting sources of fossil fuel, hybrid wind-solar energy systems can be an attractive alternative energy source to supply clean and sustainable energy for powering the IT data centers and servers. To minimize the cost and power losses in individual power converter of the conventional hybrid renewable energy system, multi-input converters (MICs) are an attractive solution. This paper proposed a new quasi-resonant soft-switched MIC with integrated power factor correction (PFC) for hybrid wind-solar energy systems. The proposed MIC topology requires only one switch in each input module and all the switches are able to achieve zero voltage switching (ZVS) turn-on and zero current switching (ZCS) turn-off for individual and simultaneous operation for different operating conditions. The operating principles of the proposed circuit are provided. Results are given on a hybrid wind-solar energy system with 48V-output to highlight the performance of the proposed circuit.
{"title":"A novel multi-input converter using soft-switched single-switch input modules with integrated power factor correction capability for hybrid renewable energy systems","authors":"S. Moury, J. Lam, V. Srivastava, R. Church","doi":"10.1109/APEC.2016.7467961","DOIUrl":"https://doi.org/10.1109/APEC.2016.7467961","url":null,"abstract":"The energy consumption of the information technology (IT) data centers and servers have been increasing rapidly for the past decade. In order to reduce global warming and conserve depleting sources of fossil fuel, hybrid wind-solar energy systems can be an attractive alternative energy source to supply clean and sustainable energy for powering the IT data centers and servers. To minimize the cost and power losses in individual power converter of the conventional hybrid renewable energy system, multi-input converters (MICs) are an attractive solution. This paper proposed a new quasi-resonant soft-switched MIC with integrated power factor correction (PFC) for hybrid wind-solar energy systems. The proposed MIC topology requires only one switch in each input module and all the switches are able to achieve zero voltage switching (ZVS) turn-on and zero current switching (ZCS) turn-off for individual and simultaneous operation for different operating conditions. The operating principles of the proposed circuit are provided. Results are given on a hybrid wind-solar energy system with 48V-output to highlight the performance of the proposed circuit.","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":"116656296","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.2016.7468133
S. Biswas, N. Mohan, W. Robbins
A systematic method of designing a zero-ripple Ćuk converter for PV/Battery-to-grid applications is presented in this paper. The integrated magnetic core design uses an intuitive flux-reluctance model to arrive at the Area Product for this kind of structure. Unlike the earlier designs for this converter, it provides a completely analytical approach to design this converter for a range of specifications. The target application is grid interface of PV or battery. The validity of the proposed method is confirmed using finite element analyses (both 2-D and 3-D), circuit simulations in pspice as well as preliminary experimental validation.
{"title":"A systematic design method and verification for a zero-ripple interface for PV/Battery-to-grid applications","authors":"S. Biswas, N. Mohan, W. Robbins","doi":"10.1109/APEC.2016.7468133","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468133","url":null,"abstract":"A systematic method of designing a zero-ripple Ćuk converter for PV/Battery-to-grid applications is presented in this paper. The integrated magnetic core design uses an intuitive flux-reluctance model to arrive at the Area Product for this kind of structure. Unlike the earlier designs for this converter, it provides a completely analytical approach to design this converter for a range of specifications. The target application is grid interface of PV or battery. The validity of the proposed method is confirmed using finite element analyses (both 2-D and 3-D), circuit simulations in pspice as well as preliminary experimental validation.","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":"121695534","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.2016.7468303
P. Ning, X. Wen, Yao-hua Li, Xiongxuan Ge
The layout of power modules is one of the key points in power module design. In this paper, along with design examples, an improved automatic layout method for planar power module is presented. Some practical considerations and implementations are introduced in the optimization procedure.
{"title":"An improved automatic layout method for planar power module","authors":"P. Ning, X. Wen, Yao-hua Li, Xiongxuan Ge","doi":"10.1109/APEC.2016.7468303","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468303","url":null,"abstract":"The layout of power modules is one of the key points in power module design. In this paper, along with design examples, an improved automatic layout method for planar power module is presented. Some practical considerations and implementations are introduced in the optimization procedure.","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":"123888042","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.2016.7468006
Zhe Zhang, M. Andersen
The dual active bridge (DAB) converter is an isolated bidirectional dc-dc topology which is the most critical part for the power conversion systems such as solid-state transformers (SST). This paper focuses on analysis and design of high frequency ac inductors which are the power interfacing component in DAB converters or DAB's derivative topologies for transferring energy between the primary and secondary sides. The DAB converter's operation principles, and the corresponding voltage and current stresses over its ac inductor are analyzed. Hereby, six diverse winding arrangements are studied in order to find a design having the lowest ac resistance and core loss. Core loss is calculated by both GSE and iGSE methods, and then the results are compared under two operating conditions. Based upon the finite element method (FEM) simulation, winding losses are investigated. Finally, the case in which the core loss and the winding loss are almost equal is selected as the optimal one. The experimental results are presented to verify the validity of the analysis and design.
{"title":"High frequency AC inductor analysis and design for dual active bridge (DAB) converters","authors":"Zhe Zhang, M. Andersen","doi":"10.1109/APEC.2016.7468006","DOIUrl":"https://doi.org/10.1109/APEC.2016.7468006","url":null,"abstract":"The dual active bridge (DAB) converter is an isolated bidirectional dc-dc topology which is the most critical part for the power conversion systems such as solid-state transformers (SST). This paper focuses on analysis and design of high frequency ac inductors which are the power interfacing component in DAB converters or DAB's derivative topologies for transferring energy between the primary and secondary sides. The DAB converter's operation principles, and the corresponding voltage and current stresses over its ac inductor are analyzed. Hereby, six diverse winding arrangements are studied in order to find a design having the lowest ac resistance and core loss. Core loss is calculated by both GSE and iGSE methods, and then the results are compared under two operating conditions. Based upon the finite element method (FEM) simulation, winding losses are investigated. Finally, the case in which the core loss and the winding loss are almost equal is selected as the optimal one. The experimental results are presented to verify the validity of the analysis and design.","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":"125136121","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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