The Wind-AVC systems have been applied to 6 wind farm bases (2/3 of total China) and 66 renewable generation substations. Until the end of 2014, the wind generation capacity that has been under control of the system reached 30.1GW, which is more than 31% of China’s total grid-connected wind generation capacity.
Figure legend: system-wide synergic control to mitigate the cascading trip risk of the wind pool areas.
Qinglai Guo, Hongbin Sun, Bin Wang, Boming Zhang, Wenchuan Wu, Lei Tang. Electric Power Systems Research, Volume 120, March 2015, Pages 234-241.
Department of Electrical Engineering, State Key Laboratory of Power Systems, Tsinghua University, Beijing 100084, China.
Integration of high levels of wind power penetration is an important feature of the emerging smart transmission grid. To address the dramatic voltage fluctuations and wind turbine generators (WTGs) cascading trip faults, which have been greatly challenged the wind pool area’s operation, a hierarchical automatic voltage control system to support wind power integration (Wind-AVC) is designed and presented in this paper. For each wind farm, an autonomous wind farm voltage controller (WFVC), which takes the details of the wind farm side grid into account, is applied to optimize the voltage and reactive power distribution inside the wind farm. Three different control modes are implemented to consider all the terminal voltages of WTGs as well as the dynamic Var reserves. A control center voltage controller (CCVC) is designed to coordinate all the distributed WFVCs. A security-constrained optimal power flow (SCOPF) based preventive control is presented, which ensures all the wind farms’ voltage satisfying the operational constraints for all the possible N − 1 scenarios. The Wind-AVC system has been put into operation in Northern China and was found to be effective in mitigating the voltage fluctuations and reducing the cascading trip risks.