应用于交直流混合配电网的PET故障穿越控制  

Fault ride-through control of PET applied to AC/DC hybrid power distribution network

作　　者：张丽萍 袁至 王维庆[1,2] 何山[1,2] ZHANG Liping;YUAN Zhi;WANG Weiqing;HE Shan(School of Electrical Engineering,Xinjiang University,Urumqi 830047,China;MOE Engineering Research Center of Renewable Energy Power Generation and Grid Connection Control,Xinjiang University,Urumqi 830047,China)

机构地区：[1]新疆大学电气工程学院,新疆乌鲁木齐830047 [2]新疆大学可再生能源发电与并网控制教育部工程研究中心,新疆乌鲁木齐830047

出　　处：《现代电子技术》2022年第17期180-186,共7页Modern Electronics Technique

基　　金：国家自然科学基金项目(52067020);国家自然科学基金项目(51767024);新疆维吾尔自治区重点实验室开放课题(2018D04005);新疆维吾尔自治区高校科研计划(XJEDU2021I010)。

摘　　要：电力电子变压器有望替代传统变压器成为交直流配电网的能量传输枢纽,当交流电网电压发生常见的单相跌落故障时,对电力电子器件及用户都会造成严重影响,需要其相应的故障穿越控制,保证电力电子变压器不会因故障闭锁脱网,并且维持其稳定的运行状态。文中提出一种适合交直流配电系统的模块化多电平变流器型电力电子变压器拓扑,并设计各部分的控制策略。首先,采用序分量控制维持不对称故障下输入级电流和电压的稳定性,在此基础上提出一种无功分段补偿控制向网侧提供无功支撑,以实现故障期间的低电压穿越。其次,调制波信号中注入合适的三次谐波,抑制电压单相跌落时子模块电容电压波动,提高故障时直流电压的稳定性。最后借助Matlab平台搭建了仿真模型,验证了该拓扑及控制策略的正确性与可行性。The power electronic transformer(PET)is expected to replace the traditional transformer to become the energy transmission hub of AC/DC distribution network.When the common single-phase drop fault occurs in the AC power grid voltage,it will cause serious impact on the power electronic devices and users,so the corresponding fault ride-through control is needed to ensure that the power electronic transformer(PET)will not be locked out of the network due to fault,and maintain its stable operation state.In this thesis,a modular multilevel converter type power electronic transformer topology suitable for AC/DC distribution system is proposed,and the control strategy of each part is designed.The sequence component control is used to maintain the stability of input stage current and voltage when an asymmetric fault appears.On this basis,a piecewise reactive power compensation control is proposed to provide reactive power support to the grid side to realize low voltage ride-through control during fault.The appropriate third harmonic is injected into the modulation wave signal to suppress the capacitor voltage fluctuation of the sub-module capacitor when the voltage single-phase sag occurs,so as to improve the stability of the DC voltage when the fault occurs.A simulation model is built by means of Matlab platform to verify the correctness and feasibility of the topology and control strategy.

关 键 词：故障穿越控制 交直流混合配电网 电力电子变压器 电压单相跌落 序分量 电容电压波动 三次谐波注入 无功分段补偿 

分 类 号：TN709-34[电子电信—电路与系统] TM42[电气工程—电器]