Design of photovoltaic inverter with active filter capability

Since renewable sources are installed at the load point through power electronic converters, in addition to providing active power, can be used for harmonic compensation, reactive power compensation and other issues to improve network performance. One of the main problems in creating such compensators due to the lack of direct access to non-linear loads current is measuring the amount of injected harmonics in the network. In this paper, by adding the active filter capability to a photovoltaic inverter, harmonics and reactive power compensation are obtained. Also, the photovoltaic converter has been changed from a two-stage structure to a single-stage one offering the simplification and lower cost of the converter structure. To overcome the problem of measuring nonlinear load harmonics, a new method of measuring the load harmonics from PCC voltage and regulating the desired compensation for the converter is proposed. The converter and control system are simulated in MATLAB SIMULINK software, where the results show the feasibility and proper performance of the proposed method.