基于有功和无功独立调节的VSC-HVDC控制策略

以电压源换流器(VSC)的稳态模型为基础,通过坐标变换推导出VSC功率传输方程的直角坐标形式.新方程只有单通道耦合作用,可以通过简单曲线描述VSC的功率传输特性,并且可以求得控制量与功率值之间的解析关系式.采用逆系统方法设计了VSC的功率传输控制系统,以及基于有功、无功功率独立调节的VSC-HVDC控制系统.仿真结果表明所设计的控制系统具有优良的控制品质,实现了VSC传输功率的独立、灵活调节,很好地实现了VSC-HVDC系统向有源网络供电时的一端定直流电压、另一端定传输功率控制.

VSC-HVDC Control Strategy Based on Respective Adjustment of Active and Reactive Power

The rectangular coordinate form of VSC's power transmission equations is deduced through coordinate conversion based on its steady state model. The new equations have only one coupling channel, according to which the VSC's power transfer characteristic can be illustrated with simple curves; and the analytic expressions between the controlling variables and power values can be deduced. The VSC translating power control system adopting inverse system nonlinear control and VSC-HVDC control system based on respective adjustment of active and reactive power are designed. Simulation results show that the control systems demonstrate excellent control performance. They can adjust the active and reactive power respectively and flexibly. VSC-HVDC system can supply an active network using the strategy that one station constant DC line voltage control and the other constant translating power control.