三相并网变流器在电网不对称故障时的有功功率安全运行区域  

Active Power Safe Operation Region of Three-phase Grid-connected Voltage Source Converter Under Unbalanced Grid Faults

作　　者：熊浩[1] 杜雄[1] 孙鹏菊[1] 籍勇亮 XIONG Haol;DU Xiong;SUN Pengju;JI Yongliang(State Key Laboratory of Power Transmission Equipment ＆ System Security and New Technology（Chongqing University）,Shapingba District,Chongqing 400044,China;State Grid Chongqing Electric Power Company Electric Power Research Institute,Yubei District,Chongqing 401123,China)

机构地区：[1]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆市沙坪坝区400044 [2]国网重庆电力公司电力科学研究院,重庆市渝北区401123

出　　处：《中国电机工程学报》2018年第20期6110-6118,共9页Proceedings of the CSEE

基　　金：国家电网总部科技项目(SGCQDK00PJJS1500069)~~

摘　　要：当电网发生不对称故障时,向电网注入有功功率可以减小有功缺额,避免大面积甩负荷。为了在保证变流器自身安全的前提下最大限度地注入有功功率,综合考虑电压源型变流器在不对称故障时可能面临的直流母线过压、过流、有功功率二倍频波动等问题,分析变流器的安全运行区域。根据安全运行区域,得到在不同故障类型、不同跌落程度下最大有功功率输出能力的解析表达式。另外,将有功功率波动不再简单地限制为0,而是限制在安全允许范围内,较大程度地提升了最大有功功率输出能力,如在单相接地故障下相对增大的百分比最高可达45%。仿真和实验结果证明了有功功率安全运行区域以及最大有功功率输出能力提升的结论。将安全运行区域分析结论应用于电网故障时的最大相电流最小化的优化控制。When unbalanced grid faults occur, the active power injection to the grid can reduce the deficit, to avoid a large area load rejection. In order to maximize the active power of the converter under the premise of ensuring the safety of the VSC, this paper considered overvoltage of the DC bus, the overcurrent, active power oscillation that the converter may face in asymmetric fault, the safe operation region （SOR） of converter was analyzed. According to the safe operation region, the analytical expression of the maximum active power output capability under different fault types with different fault strength was obtained. In addition, the active power oscillation was no longer limited to 0, but it was limited in the range of safety, so as to improve the maximum active power output capability. For example, the relative increase percentage in the single-phase ground fault is experiment results show that up to 45%. The simulation and the active power safe operation region is correct and the maximum active power output capability is improved. And the application of the safe operation region analysis conclusion was applied to the minimum current control under unbalanced conditions.

关 键 词：并网变流器 不对称电网故障 最大有功功率 安全运行区域 优化控制 

分 类 号：TM46[电气工程—电器]