两级式光伏系统的低电压穿越控制技术  

Low Voltage Ride through Control Strategy for Double-stage Photovoltaic System

作　　者：程永乐[1] 王冰[1,2] 周建良[1] 

机构地区：[1]河海大学能源与电气学院,南京211100 [2]河海大学可再生能源发电技术教育部工程研究中心,南京211100

出　　处：《科学技术与工程》2014年第1期36-40,共5页Science Technology and Engineering

基　　金：国网科技项目(规模化光伏发电运行控制关键技术研究与示范);国家自然科学基金(51007019)资助

摘　　要：针对光伏系统在电网电压跌落时可能产生过流、过压的情况,在传统双闭环控制策略的基础上,采用无功控制与Crowbar电路相结合的方法对光伏系统进行控制,使系统具有低电压穿越的能力。采用有功、无功电流协调分配的无功控制,不但能够解决电网电压发生跌落时的过流问题,而且能够根据电网电压跌落幅值,利用光伏电站自身的无功补偿特性向电网提供一定的无功功率;Crowbar保护电路则能够保证直流侧电压在安全范围内。最后通过仿真验证了该方法的正确性和有效性。The photovoltaic （PV） system may produce overcurrent, overvoltage when grid voltage drop occurs. To deal with the problem, based on the traditional double-loop control strategy, the method of combining reactive power control with Crowbar circuit, which can improve the capability of low voltage ride through （LVRT） is proposed. Through coordinating the active current and the reactive current, the method can solve the overcurrent problem. At the same time, by using the reactive compensation of photo- voltaic power plant, the method provides reactive power to grid based on the amplitude of grid voltage drops. Finally, the simulation results show the correctness and effectiveness of the control strategy.

关 键 词：无功控制 CROWBAR 电压跌落 低电压穿越 无功补偿 

分 类 号：TM615[电气工程—电力系统及自动化]