Active Disturbance Rejection Control of a SEPIC Converter

Single-ended primary inductor converter(SEPIC) is a high-gain buck-boost converter, but its controller’s design is a challenging task as it is a fourth-order nonlinear system. This paper proposes an active disturbance rejection control (ADRC)-based controller for a SEPIC converter with high switching frequency. ADRC is an advanced control technique that does not rely on the exact information of the system as all the external and internal disturbances are estimated as separate variables and are canceled directly by the effect of the controller. Simulation results suggest that the proposed ADRC technique gives good setpoint tracking and robustness toward disturbances like input voltage fluctuations and load variations. The performance parameters have been calculated and analyzed to conclude that the proposed method has stable and robust performance.