A novel adaptive backstepping controller for stabilization of DC/DC converter feeding constant power load

Abstract

Power electronic converter loads are widespread in DC distributed power system. These tightly controlled converter loads behave as constant power loads (CPL) and may cause stability issue when fed by a source converter. This paper proposes a nonlinear control method to stabilize DC/DC boost converter feeding CPL. The proposed controller is based on adaptive backstepping and nonlinear disturbance observer techniques. Following the step-by-step backstepping algorithm, the designed controller achieves global stabilization of the system. With the load variation estimated by nonlinear disturbance observer (NDO), DC bus voltage can be accurately tracked with fast transient response. The proposed controller not only ensures large signal stability under large disturbance of CPL, but also features high performance at wide operating range. Simulations in Matlab/Simulink are conducted to verify the proposed strategy.