Second-Order Ripple Minimization in Single-Phase Single-Stage Onboard PEV Charger

This article presents a single-phase, single-stage onboard plug-in electric vehicle (PEV) charger. The single-phase PEV chargers have an inherent problem of introducing a second-order ripple component on dc side. This problem is further exaggerated during the vehicle-to-grid (V2G) mode of operation where it may be normally controlled to supply both active as well as reactive power. During the V2G reactive power compensation, the second-order harmonics ripple component at dc side will increase, which further reduces the life cycle and performance of battery pack. Therefore, a second-order ripple component compensation technique is proposed by precompensating the reference current itself. The resultant reference current is periodic in nature, and accordingly, a repetitive controller (RC) is used, which is well known for its capability of tracking the periodic signals. The PEV charger is controlled in both grid-to-vehicle (G2V) and V2G modes. In this article, the performance of the controller has been tested in eight different modes on active-reactive (P-Q) power plane and found that ripple minimization technique successfully reduced second-order ripple component on dc side. The PEV charger controller has been simulated in MATLAB/Simulink environment and implemented on the scaled down experimental setup.