Enhancing reliability and power density of single-phase PHEV charger using an integrated active filter

摘要

One of the conversion systems applicable in the chargers of Plug-in Hybrid Electric Vehicles (PHEVs) is Single-phase PWM AC/DC converter. The main challenge concerning single-phase conversion systems is the pulsating power at the AC side, which pulsates at the twice the grid frequency, and should be effectively filtered. In the PHEVs' chargers, the lack of the appropriate filtering of this power will lead to the emergence of a significant second-order voltage harmonic at the battery side, which will cause the overheating and degrading the battery lifetime and performance. This paper proposes a new active method to filter out the pulsating power. In this technique, the pulsating power is absorbed by a capacitive auxiliary energy storage element, which prevents it from being transferred to the DC side. One of the advantages of the proposed method compared to other existing methods is that it can provide the minimum amount of current stress. By employing the suggested method, the weight, size and implementation cost of the charger can be decreased, as well as its reliability and power density can be increased. The performance of the proposed method is investigated and verified by extensive simulations in MATLAB/Simulink environment.