A bang-bang control strategy of HVDC to improve transient stability in the AC/DC system

This paper presents an automatic bang-bang control strategy of HVDC power flow based on equal-area criterion. The proposed strategy has taken into account the restraints on both amplitude of power flow change, and rate of change. This strategy is evaluated on an AC/DC system model in EMTDC/PSCAD. Simulations with several faults in different places show that the proposed strategy allows a significant improvement of the system transient stability after a large disturbance. The rate of the power flow change is an important impact factor of the control strategy.