Step Response of High Feedback Gain Changeable Control DC-DC Converter

In this paper, the already proposed high feedback gain switching method has the optimum setting for a specific load step. Therefore, we investigate the optimal setting of the proportional gain switching for various disturbance such as the line and load fluctuation, which could occur in the renewable energy system. As a result, the following setting of the proposed method is optimum: the optimum setting when the gain changing duration and the proportional gain in the transient state are set to 14.4 ms and 30, respectively. The proposed method is effective for an improvement of the transient response avoiding the limit cycle oscillation. The transient characteristics of the proposed method are improved compared with the conventional PID control. Therefore, the proposed method is effective in the renewable energy system.