Coordinated design of PSS and multiple FACTS devices based on the improved steepest descent algorithm to improve the small-signal stability of wind-PV grid-connected system

Abstract

The integration of renewable energy has a significant impact on the stability of the power system, especially the unpredictable threat on the small-signal stability. The flexible AC transmission system (FACTS) devices can quickly adjust the fundamental wave power flow to improve the transmission capacity and stability of power systems. This paper proposes an improved steepest descent algorithm (SDA) to coordinate and optimize the control parameters of PSS, TCSC and UPFC-PODC, the initial values and ranges of parameters are determined by the critical eigenvalue locus movement (ELM). Extensive simulations on the eight machines twenty-four buses power system verify the effectiveness of the proposed method on improving the damping level and restraining the low frequency oscillation.