Implementation of Harmonic Compensation for Three-Phase Grid-Connected Voltage-Source Converter Under Grid Voltage Distortion

This paper presents an implementation methodology for a current harmonic compensation technique of three-phase grid-connected voltage-source converter (VSC), which was applied under the grid voltage distortion and frequency variation. The proportional-integral plus multi-resonant controllers (PIMR) were used to mitigate the high order harmonic current. The PIMR controller was transformed to the discrete-time domain and implemented on a TMS320F28379D digital signal processor. The proposed control scheme was validated with a hardware in the loop (HiL) and with a 5 kW three-phase LCL-filtered grid-connected VSC. The harmonic compensators were used in the dq-frame at harmonic orders 6th and 12th for suppression of the grid voltage harmonic orders 5th, 7th, 11th, and 13th. Results from MATLAB/Simulink simulation and experiments with HiL and hardware implementations were found to be in close agreement. The experimental grid current exhibited excellent harmonic rejection with a total harmonic distortion close to 1% and complied with the IEEE 1547 standard. The grid current can tracked the reference command with a fast dynamic response.