A Nonlinear Boundary Controller For Buck Converters Feeding Constant-Power Loads

Constant-Power Load (CPL) introduces destabilizing effect to dc-dc converters, which may lead to voltage oscillation or collapse. To mitigate the destabilizing problem brought by CPL, a nonlinear boundary controller is proposed in this paper, which has a nonlinear switching line. The converters' dynamics on the state space plane is analyzed through phase portrait. The proposed controller is verified by simulation tests in MATLAB/Simulink for controlling the output voltage of a buck converter with CPL.