采用广域测量信息反馈的广域PSS参数设计

Parameter Design for Wide-area PSS Using Global Signals

根据互联电网区间振荡的特点,可将参与振荡的机群按各自的"部分惯性中心"等值为两机系统。文中首先推导了等值两机系统的电磁转矩系数,为区间振荡模式的电磁转矩分析奠定了理论依据。在此基础上提出了双通道反馈结构的广域电力系统稳定器(PSS),并采用建立在同步转矩及阻尼转矩概念上的扩展相位补偿法,进一步推导了反映广域反馈信号与本地反馈信号之间关系的传递函数,然后进行相量坐标映射变换,最后系统研究了广域PSS的参数设计。仿真结果表明:它能有效抑制系统的区间低频振荡,提高系统的小信号稳定极限,与其他稳定器设计方法相比,能够进一步改善系统阻尼特性。

Based on the inter-area oscillation characteristics in interconnected power system, the machines participating in oscillation can be equivalent to a two-machine system according to their respective inertia center. The electromagnetic torque coefficient for the equivalent two-machine system is firstly deduced, which lays foundations for the electromagnetic torque analysis of inter-area oscillation mode. On this basis a wide-area power system stabilizer （PSS） with two-channel feedback structure is presented, and the extended phase compensation method is adopted to coordinate mapping and conversion by a transfer function between wide-area and local feedback state variables. At last the design method of the parameters for the wide-area PSS is provided systematically. Simulation results show that it can not only damp inter-area modes effectively, but also improve small signal stability limit. Compared with other stabilizer design methods, the approach proposed is helpful to improve the damping characteristics of the system.