A Harmonic Mitigation Strategy for V2G Grid Integration Based on Repetitive Control

Abstract

Large-scale grid integration of renewable energy and power electronic devices leads to power quality problems including grid harmonic distortion. To solve these problems, this paper proposes a V2G grid-connected harmonic mitigation strategy that combines repetitive control and PI composite control based on the bidirectional energy interaction feature of Vehicle-to-Grid (V2G). This paper first constructs a two-level AC/DC-DC/DC grid-connected topology and a mathematical model of three-phase converters, and realizes independent regulation of active and reactive power via decoupled control. Traditional PI control fails to accurately track and compensate high-order periodic harmonics, so repetitive control is introduced to eliminate harmonics with zero steady-state error and form a composite control scheme. A simulation model is established according to theoretical analysis and tested under both charging and discharging conditions. Simulation results prove that the proposed composite control strategy can effectively reduce the total harmonic distortion (THD) of grid current, improve grid power quality and guarantee stable bidirectional power transmission of the V2G system.