电压源换流器高压直流输电的控制策略及其参数优化(英文)

Novel Control Strategy for Voltage Source Converter Based HVDC and Controller Parameters Optimization

提出一种电压源换流器高压直流输电(voltage source converter based on high voltage direct current,VSC-HVDC)的新型控制策略。基于VSC-HVDC的稳态模型,通过坐标变换和变量代换推导出一组功率传输方程。结合PI控制器和非线性逆系统的思想设计了相应的控制器,并推导出在该控制器下VSC-HVDC的有功功率和无功功率的传输极限。从圆特性出发,在理论上证明所设计的控制器可以实现有功功率和无功功率的完全独立控制。采用Hooke-Jeeves算法对控制器的参数进行了优化。PSCAC/EMTDC下的仿真结果表明:采用优化后的PI参数,系统性能得到很大改善;而且所设计的控制器可以实现有功功率和无功功率的独立控制,并具有快速的响应速度、良好的稳定性和较好的鲁棒性。

This paper proposes a novel control strategy for voltage source converter based high voltage direct current （VSC-HVDC）. Based on its steady state model, a series of mathematical analysis expressions for power delivery were deduced using the coordinate conversion and variables substitution in terms of the original equations. The corresponding power controllers were designed using the PI controller and the nonlinear inverse system. Based on the designed strategy, the transmission limits of the active and reactive power were deduced. According to the circle characteristics of operation represented, it was theoretically proved that the control strategy could independently control the active and reactive power. Hooke-Jeeves algorithm was adopted to optimize the PI parameters of the proposed controllers for VSC-HVDC system. Simulation results obtained by using PSCAD/EMTDC show that better operation characteristics can be achieved with the support of optimized PI parameters. Moreover, the proposed controllers can independently control the active and reactive power with high response speed, desirable stability and strong robustness.