Investigation of Full-Order State Output Feedback Controller on DC-DC Converter Rapid Load Current Change

Abstract

A DC-DC converter produces constant output voltage in the face of varying supply voltage, load current change, and circuit element variation. To achieve tight output voltage regulation in the presence of various disturbances, DC-DC converters incorporate a control strategy to regulate power flow and power level. In recent times, several control strategies have been investigated for regulating the action of DC-DC converters, ranging from the conventional frequency domain to time domain design approaches. However, not enough attention is given to the performance of the state feedback controller, especially during rapid load current change in dc-dc converter. In this paper, a full order state-feedback controller was designed, and the performance was investigated for rapid load current change. A state feedback controller was first designed in this work, and then the integrator is introduced to eliminate the inherent steady-state error for improved system robustness to disturbance rejection. The state feedback controller performance was evaluated by subjecting the converter to various step load current changes in which the controller rejected the disturbance faster when compared with the PID controller used as a base controller. The fast transient response will allow the DC-DC converter to accept wider current change from rapidly changing loads and achieve improved output voltage regulation.