Reactive Power and Voltage Coordinated Optimal Control with Energy Storage and Synchronous Condenser to Suppress DC Subsequent Commutation Failure

Abstract

Commutation failure threatens the safe operation of power grid. At present, dynamic reactive power equipment is widely used to suppress commutation failure, such as synchronous condenser, SVC and STATCOM. After commutation failure, dynamic reactive power supports the voltage recovery of converter AC bus to suppress the subsequent commutation failure. With the accelerated development of energy storage, this paper puts forward that energy storage and synchronous condenser participate in emergency control system to suppress the subsequent commutation failure of DC. Firstly, the reactive power control characteristics of energy storage and synchronous condenser are analyzed, and the engineering feasibility of emergency control system to suppress subsequent commutation failure is involved. Then, the reactive power and voltage control strategies of the energy storage and synchronous condenser are put forward in three stages: before the fault, after the DC commutation failure and after the recovery of DC commutation failure. Reserved transient reactive power capacity in steady-state operation before the fault. Emergency control provides large reactive power output after commutation failure. Finally, the effectiveness of coordinated optimal control of reactive power and voltage of energy storage and synchronous condenser to suppress subsequent commutation failure of DC is verified by an actual power grid simulation example.