Improvement of commutation failure predictive control considering AC voltage disturbance

Abstract

Commutation failure is one of the most common faults in HVDC system, and the predictive control of commutation failure is an important means to prevent commutation failure. In this paper, the disturbance mechanism caused by the AC filter to the predictive control of commutation failure is analyzed in detail from the aspects of discrete action characteristics and control principle of circuit breaker. And at the same time, the feasibility of control strategy improvement is also analyzed from the detection. In order to thoroughly solve the influence of slight AC system disturbance on commutation failure predictive control and HVDC transmission system, such as the input of AC filter,the characteristics of DC current variation during AC system disturbance and failure are analyzed, and the new electrical parameters are introduced as auxiliary criteria to improve the commutation failure predictive control principle. The simulation results show that, the optimized commutation failure predictive control has stronger ability to resist the disturbance of AC system, higher applicability to HVDC project, and is more conducive to the stable operation of HVDC system.