High-Frequency Resonance Mitigation for Plug-In Hybrid Electric Vehicles’ Integration With a Wide Range of Grid Conditions

An adaptive virtual resistor-based controller is proposed to resolve the high-frequency resonance and controller instability issues associated with the integration of plug-in hybrid electric vehicles (PHEVs) with different grid conditions. The issues related to grid integration of PHEVs are presented and analyzed. When connected with different grids, the variety of grid impedance, results in the instability of the controller with fixed compensation gain. The proposed controller uses grid current and filter capacitor current to form a virtual resistor controller. Furthermore, the resonant frequency is extracted and is the criterion used to tune the compensation gain to make the proposed control behave as a controllable virtual resistor. The control-loop modeling, design, and analysis are presented. The adaptive tuning capability is analyzed. The control loop is designed under different grid conditions and the control robustness to the impedance variation is examined. The experimental results verify that the proposed controller can be applied to a wide range of grid conditions stably and can also achieve good performance with regard to total and individual harmonics.