Regional Generator Excitation Control Strategy for HVDC Commutation Failure Suppression

The stability of the DC system has become the key to the stability of the entire system. The generators in power grid as a reactive power source could be used for dynamic reactive power compensation. The generator which is strong correlation with the busbar voltage of the converter station is determined by analyzing the voltage/ reactive sensitivity analysis. The short-time forced excitation control strategy in the determined generator is proposed in this paper. In this strategy the target bus voltage is used as the control target. So dynamic reactive power support is provided to avoid commutation failure when AC bus voltage of DC converter station has achieved the low level. The purpose of exploiting the potential of resources of power grid to enhance the transient voltage stability is achieved. Finally, the simulation verified that the generator excitation control strategy in this area can effectively suppress the commutation failure of DC system.