基于背靠背 VSC-HVDC 电网间同期并列装置实现UPFC 的仿真研究

基于电压源型换流器(VSC)能够同时独立控制有功功率和无功功率的原理,对背靠背VSC-HVDC同期并网装置结构和统一潮流控制器(UPFC)电路主拓扑结构进行分析,提出一种基于功率传递方式实现电网并网与UPFC功能相结合的控制策略。电压源型换流器完成同期并网操作后,采用断路器状态作为特征信号闭锁并联侧和串联侧的换流器,通过相关电气设备的操作完成UPFC结构的转换,改变换流器控制策略以实现潮流调节功能。同一装置在不同模式下实现多种功能,提高了电力系统的稳定性和自动化程度,增加设备的使用率。本文利用PSCAD/EMTDC仿真软件验证了该方法的有效性和可行性。

Simulation Study on Achieving UPFC of Simultaneous Paralleling Device Based on Back to Back VSC-HVDC

In this paper,the structure of back to back VSC-HVDC simultaneous paralleling device and main topological structure of unified power flow controller(UPFC)circuit are analyzed based on the principle that voltage source converter(VSC)can control independently both active and reactive power and a kind of control strategy which realize the control strategy of achieving power system synchronization by power transmission and UPFC functions is proposed.After the simultaneous parallel operation of VSC,the circuit breaker status is used as the feature signal to lockout the converter at both parallel and series side and the transformation of UPFC structure is finished through operation of related electrical equipment,so to change the control strategy of converter and achieve the flow adjustment function.The same device achieves multiple functions under different modes so to improve stability and automation degree of power system and increase the utilization rate of the equipment.The PSCAD/EMTDC simulation is used to verify effectiveness and feasibility of the method.