Abstract
Fault-tolerant operation ability is of great importance for stable operation of cascaded H-bridge (CHB) converters, under open-circuit (OC) or short-circuit (SC) switch failures in submodule (SM). In this article, an improved fault-tolerant control strategy is proposed for CHB-based static synchronous compensator (STATCOM) under SM faults. First of all, compared with the conventional fault-tolerant method of directly bypassing the faulty SMs, the proposed fault-tolerant method takes advantage of the healthy switches of the faulty SMs, where they are still able to generate either positive or negative voltage level. As a result, more output voltage levels can be generated, and it raises the attainable balanced line-to-line voltage, especially when different fault types exist at the same time. Then, based on the specific condition of OC fault or SC fault, when the output voltage reference of the faulty phase reaches its limit, the references of the other two healthy phases are redistributed to generate the desired line-to-line voltage. With the reconfiguration of modulation waves, the attainable balanced line-to-line voltage can be further improved. In addition, the proposed fault-tolerant method possesses the ability of cluster voltage balancing, which is an important issue for the STATCOM application. Simulation and experimental results validate the effectiveness of the proposed fault-tolerant method.
| Originalsprog | Engelsk |
|---|---|
| Artikelnummer | 9032336 |
| Tidsskrift | IEEE Transactions on Industrial Electronics |
| Vol/bind | 68 |
| Udgave nummer | 4 |
| Sider (fra-til) | 2784-2797 |
| Antal sider | 14 |
| ISSN | 0278-0046 |
| DOI | |
| Status | Udgivet - apr. 2021 |
Bibliografisk note
Funding Information:This work was supported in part by the National Key Research and Development Program of China under Grant 2017YFB0903300, in part by the Project of National Natural Science Foundation of China under Grant 51625702 and Grant 51807135, and in part by the Joint Fund Project of National Natural Science Foundation-State Grid Corporation under Grant U1766210.
Funding Information:
was supported in part by the National Key Research and Development higher output voltage, and so on [5]. With the rapid development ProgramofChinaunderGrant2017YFB0903300,inpartbytheProject of power technology and the widely applied power electronic de-andGrant51807135,andinpartbytheJointFundProjectof Na-ofNationalNaturalScienceFoundationofChinaunderGrant51625702 vices, power quality is becoming an important and serious issue tional Natural Science Foundation-State Grid Corporation under Grant [6]. As one of the most effective compensation devices, static U1766210.(Correspondingauthors:LinglinChen;HongjieJia.) synchronous compensator (STATCOM) draws much attention SmartGridofMinistryofEducation,TianjinUniversity,Tianjin300072,QianXiao,YunfeiMu,andHongjieJiaarewiththeKeyLaboratoryof in recent years [7]. It can effectively compensate for the reactive China, and also with the Key Laboratory of Smart Energy & Informa-current, improve the power factor, and reduce the power loss on tionTechnologyofTianjinMunicipality,Tianjin300072,China(e-mail: power transmission, thereby enhancing the stability of the power LinglinCheniswiththeDepartmentofElectricalandElectronicsEn-xiaoqian@tju.edu.cn;yunfeimu@tju.edu.cn;hjjia@tju.edu.cn). network [8]–[11]. For high-voltage STATCOM applications, gineering, University of Nottingham, NG7 2RD Nottingham, U.K. (e-mail: cascaded H-bridge (CHB) converter is one of the most superior exlc15@nottingham.ac.uk). topologies due to its modularity, scalability, and so on [12]–[14]. tomation,HarbinInstituteofTechnology,Harbin150001,China(e-mail:Yu Jinis withthe DepartmentofElectricalEngineering andAu- In high-voltage high-power applications [15], there are many hitjy19940213@163.com). submodules (SMs), each containing four power switches and one AllanFagnerCupertinoiswiththeFederalUniversityofMinasGerais, capacitor, as shown in Fig. 1. The open-circuit (OC) fault and MaterialsEngineering, FederalCenterfor Technological EducationofBelo Horizonte31270-901,Brazil,andalsowiththeDepartmentof short-circuit (SC) fault of IGBTs may even lead to the interrup-Minas Gerais, Belo Horizonte 30421-169, Brazil (e-mail: afcupertino@ tion of the CHB STATCOM, due to the cascaded connection of ieee.org). each H-bridge [16]. As a result, the fault-tolerant control method puterEngineering,UrmiaUniversity,Urmia5756151818,Iran(e-mail:Yousef Neyshabouri iswiththeSchoolof ElectricalandCom- for CHB STATCOM has to be studied. Many studies have been y.neyshabouri@urmia.ac.ir). carried out on fault-tolerant control of CHB-based converter, Tomislav Dragicˇevic´ and Remus Teodorescu are with the Depart- which mainly can be divided into three categories, additional (e-mail:tdr@et.aau.dk;ret@et.aau.dk).mentofEnergyTechnology,AalborgUniversity,9220Aalborg,Denmark power unit (APU) method, special modulation technique (SMT), This article has supplementary downloadable material available at and zero-sequence voltage (ZSV) injection method. http://ieeexplore.ieee.org,providedbytheauthors. For APU methods, an additional unit with an isolated dc onlineathttp://ieeexplore.ieee.org.Colorversionsofoneormoreofthefiguresinthisarticleareavailable voltage source is used [17] to provide a postfault operation Digital Object Identifier 10.1109/TIE.2020.2978716 ability. However, the additional isolated dc source is usually
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