基于微网储能变流器的故障穿越控制  

FAULT RIDE-THROUGH CONTROL BASED ON MICROGRID ENERGY STORAGE CONVERTER

作　　者：吴东 汪海宁[1] 房志学 罗琴琴 Wu Dong;Wang Haining;Fang Zhixue;Luo Qinqin(Hefei University of Technology,Hefei 230009,Research Centerfor Photovoltaic System Engineering of MOE China)

机构地区：[1]合肥工业大学光伏系统教育部工程研究中心,合肥230009

出　　处：《太阳能学报》2020年第10期66-73,共8页Acta Energiae Solaris Sinica

基　　金：国家重点研发计划(2017YFB0903503)。

摘　　要：微网中需要能够提供电压和频率支撑的电压源型变流器,针对公共连接点电压跌落情况,提出一种基于电流下垂的故障穿越控制策略,电流下垂采用有功电流-频率、无功电流-电压控制,无需功率计算,可避免故障时输出有功电流的过流现象;采用虚拟阻抗连接下垂与电流内环,通过动态调整内环无功电流指令限幅值,提供无功支撑;针对故障穿越过程中可能存在的功角失稳及故障后电流恢复响应慢的问题,提出一种功角限幅控制。在故障时采用滞环控制器,将功角保持在故障前稳态值的一定范围内,使其平稳度过故障暂态阶段,且能够在故障清除时快速恢复到故障前的状态。仿真和实验验证了所提方法的可行性和有效性。The voltage source converter is necessary for microgrids to maintain the voltage and frequency. A control strategy based on current droop is proposed,which can make the converter capable of riding through the fault of the voltage sag at the point of common coupling. The current droop adopts by the active current-frequency control and reactive current-voltage control which has the merit of no need to calculate the powers,and avoiding overcurrent of the active current. The reactive power support function is provided by regulating the reactive current limiting. Aiming at the problem of power angle instability and slow response of current recovery after fault,a power angle limiting control is proposed. The hysteresis controller is employed to constrain the power angle within a certain range around the pre-fault steady state value so that the converter can ride through the transient state smoothly and recover to the pre-fault state rapidly. The proposed strategy is verified with simulations and experiments.

关 键 词：微网 储能 电压源变流器 电流下垂 无功支撑 功角限幅 

分 类 号：TM7[电气工程—电力系统及自动化]