基于不对称分析的高压链式STATCOM的低压穿越控制策略  

Low voltage ride through control strategy of high voltage cascaded STATCOM based on asymmetric analysis

作　　者：刘刚[1] 张扬[1] 高志军[1] 孙健[1] 张建[1] 

机构地区：[1]许继集团有限公司,许继电气股份有限公司,河南许昌461000

出　　处：《电力系统保护与控制》2015年第21期112-119,共8页Power System Protection and Control

基　　金：国家电网公司2014年科技项目“静止同步发电机(SSG)技术及应用前期研究”

摘　　要：作为新能源电站的主要无功补偿和电压支撑设备,高压链式静止同步补偿器(STATCOM)也需具备低电压穿越的能力,特别是三相电网电压不对称故障的低压穿越能力。为解决此难题,采用对称分量法分别分析了电网侧和换流链侧,并推导出数学公式,结合该公式提出了一种基于负序电流注入的高压链式STATCOM的低电压穿越控制策略。该策略包含了控制算法和控制逻辑,能够满足三相电网对称以及不对称下的跌落工况。通过仿真和试验,验证了该方法的有效性,并将其应用于工程实践中。As a key electric equipment for reactive power compensation and voltage support in new energy substations, high voltage cascaded STATCOM needs low-voltage ride-through（LVRT） capacity, especially under the asymmetrical fault of three-phase grid voltage. To solve this problem, this paper analyzes grid side and conversion chain side respectively by using symmetrical component method and deduces a mathematical formula. And based on the formula, a LVRT control strategy of high voltage cascaded STATCOM based on negative-sequence current injection is proposed. The proposed strategy includes control algorithm and control logics, which can satisfy voltage-drop under both three-phase symmetric and asymmetric grid. The validity of the method is verified by simulations and experiments, and it has been applied in engineering application.

关 键 词：不平衡分析 低电压穿越 负序电流注入 链式STATCOM 

分 类 号：TM761.12[电气工程—电力系统及自动化]