Minimized Total Harmonic Distortion of a Multi-level Inverter of a Wind Power Conversion Chain Synchronized to the Grid-LCL Filter Optimization and Third Harmonic Cancellation

In order to improve the wind power conversion chain performance on the grid side, this work proposes the use of multi-level inverter and a fairly high switching frequency for an optimized LCL filter, while respecting the grid connection conditions. The method used consists of reducing the total harmonic distortion and adjusting filter parameters to cancel the third order harmonic. For grid-side chain control, two cascaded current and voltage control loops are used to generate the inverter pulse width modulation. To ensure synchronization even in the presence of grid faults or unbalance, a phase-locked loop (PLL) circuit with a multi-variable band-pass filter (MVBPF) is adopted. To validate the theoretical study, simulations are performed for a 300 W chain with a two-level, three-level, and five-level inverter using three different filters. A comparative study of the results shows that the use of the five-level inverter with the optimized filter effectively reduces ripples while meeting grid coupling conditions.

Cite this article as: W. El Maataoui, S. El Daoudi, L. Lazrak, and M. Mabrouki, “Minimized total harmonic distortion of a multi-level inverter of a wind power conversion chain synchronized to the grid-LCL filter optimization and third harmonic cancellation,” Electrica, 22(1), 27-40, Jan. 2022.