Applications of wide-area adaptive HVDC and generator damping control in Chinese power grids

Abstract

With the economic growth and the renewable energy integration increase, the weakly damped low frequency oscillation has become a major threat to the system stability in China's interconnected power systems. In this paper, some practical work on the applications of synchro-phasor measurement techniques in the field of wide area damping control are presented. The design, implementation and commission of the adaptive wide-area damping control (WADC) system through the modulations of multiple HVDC links and generator exciters are elaborated respectively. Two different adaptive control approaches, i.e., Prony-based and Mode-free Adaptive Control (MFAC), are implemented to adapt to the system change. In addition, time delay and coordination requirements are also considered in the design procedure. The WADC-HVDC system has been commissioned in the practical China Southern Grid (CSG). The field test results show that the coordinated WADC-HVDC system can effectively increase the damping ratios and power transfer capacity. WADC system that regulating the generator exciters are also implemented in CSG and Central China Grid (CCG) to increase the system stability. The performance has been verified via digital simulations conducted in CSG and CCG.