An Experimental Study on Accuracy Improvement in Grid Connection Inverter with Load Estimation

Abstract

The grid connection inverter is built in the PCS (Power Conditioning Subsystem) for the distributed power supply, such as photo voltaic system. In order to utilize the power source, it is necessary that the grid connection inverter of the PCS predicts the load and output fluctuation in customer side. Therefore, this paper investigates a load estimation in the grid connection inverter of the PCS. The proposed estimation method adds superimposing perturbative signals in the inverter reference. The validity of the proposed estimation method is experimentally verified. In addition, the perturbative signals for load estimation consist of three different frequency components. As the result, it is experimentally clarified the proposed method improves the estimation accuracy.