中压电网中光伏逆变器故障穿越控制策略  

CONTROL STRATEGY OF FAILURE RIDE-THROUGH OF PV INVERTER CONNECTED TO MEDIUM-VOLTAGE GRID

作　　者：周峰武[1] 邓哲[1] 吕征宇[1] 

机构地区：[1]浙江大学电气工程学院,杭州310027

出　　处：《太阳能学报》2014年第8期1441-1448,共8页Acta Energiae Solaris Sinica

基　　金：国家自然科学基金(50677063)

摘　　要：针对分布式发电系统的中压电网技术导则(MVD),以三相三电平光伏并网逆变器为研究对象,在电网发生对称故障时,功率不平衡会导致逆变器直流母线电压不稳定和逆变器输出电流过冲,此时采用直接功率控制方法,使光伏逆变器按照入网导则的要求进行故障穿越;当电网发生三相不对称故障时,采用改进的正、负序电流双环控制器,抑制负序电流,使逆变器能稳定工作且向电网供应THD值较小的电流,在保证电能质量的前提下实现故障穿越。On account of Medium-Voltage Directive （MVD） for distributed generation systems, taking the three-phase three-level PV grid-connected inverter as study object, when the symmetrical faults of three-phase grid occur, the voltage of the DC bus of the PV inverter will be unstable and the output current of the PV inverter will get overshoot because of the unbalanced power. In this situation, the method of direct power control is used to achieve the fault ride- through of the inverter according to the Medium-Voltage Directive. When the grid unbalanced faults occur, improved positive and negative sequence dual current control scheme is use to suppress the negative-sequence current and make the inverter operate steadily, simultaneously supply the grid with the current of low THD, achieve the goal of fault fide- through on the premise of good power quality.

关 键 词：中压电网 光伏逆变器 故障穿越 功率管理 改进型正负序双电流控制 

分 类 号：TM464[电气工程—电器]