Gravitational Search and Sine Cosine Algorithms to Enhance the VSC-HVDC System Performance under Different Disturbances

Abstract

This paper focuses in studying the dynamic response of the voltage source converters high-voltage direct current (VSC-HVDC) connected to grid. In order to get faster response the magnitude of the active power, reactive power and the DC link voltage should be controlled. Optimizing the parameters of PI (proportional integration) controller is necessary to control the said quantities. In this context meta-heuristic optimization methods i.e. gravitational search algorithm (GSA) and sine cosine algorithm (SCA) are used to obtain optimal parameters of PI controller. GSA algorithm is based on the gravity law for Newton while SCA depends on mathematical model based on cosine and sine functions. It is worthy to mention these algorithms have an efficient global search capability. Using MATLAB™ Simulink, model of VSC-HVDC system is presented. This system is exposed to different disturbances for demonstrating its dynamic response. Simulation results exhibit the dynamic response is improved with the optimal gains than that of default ones.