南方交直流混合电网区域振荡的协调控制策略

Research on Coordinated Control Strategy for Inter-area Oscillations in China Southern AC/DC Power Grid

针对南方电网弱阻尼区域振荡模式的抑制问题,在分析了电力系统稳定器(PSS)、直流阻尼调制的控制机理及其控制效果的基础上,考虑到南方电网近距离直流多落点的特点,提出了一种PSS和直流阻尼调制的协调控制策略。在该策略中,结合模式可控性指标首先进行相关控制点的PSS参数优化以抑制直流调制不敏感的模式,在前一层优化的前提下再进行直流阻尼调制控制器的参数优化。这样既能保证二者的协调控制,又能有效地控制优化进程和降低计算量。最后通过仿真计算验证了协调控制策略的合理性和有效性。此工作可为研究近距离直流多落点交直流混合电网的低频振荡抑制问题提供新思路。

In order to suppress weakly-damped inter-area oscillation in the China Southern Power Grid （CSG）, control mechanism of power system stabilizers （PSS） and HVDC damping modulation as well as their control effects are analyzed, and a coordinated control strategy between PSS and HVDC damping controllers is put forward in view of multi-HVDC inverters electrically adjacent in the same AC system of CSG. In the proposed scheme, referring to the controllability indices, parameter optimization of selected PSS is firstly implemented to suppress the modes to which HVDC modulation shows low control sensitivity. Based on the first level of optimization, the parameter optimization of HVDC damping controllers in CSG are then realized. The advantage of this arrangement is that it can achieve the coordination between both means while control the optimization course and decrease the calculation quantum, which facilitates its application in practical large-scale AC/DC hybrid grid. Finally, the rationality and validity of the control strategy supposed are verified by simulation tests. Researches in this paper provide new idea for suppression of inter-area oscillations in large-scale AC/DC hybrid grid with multi-inverter stations located in the proximity of the same AC system.