偏磁对电动汽车充电设备的影响及抑制方法研究

Study on the Influence and Suppression Method of Magnetic Bias for EV Charging Equipment

建立电动汽车充电设备的近似数学模型,在此基础上讨论偏磁对充电设备正常工作的影响,说明偏磁问题的研究对充电设备的重要性。针对电动汽车充电设备,假设几种可能引起偏磁的因素,并从数学上推导这些因素与偏磁的关系,得出功率管IGBT的参数不对称和变压器漏感的存在能够引起或加剧偏磁,而隔直电容和变压器初级绕组的电阻能够减小或消除偏磁的结论。根据该结论,提出电动汽车充电设备抑制偏磁的硬件设计原则,并通过仿真验证了这一原则的有效性。

This paper established the approximation mathematical model of electric vehicle charging equipment,based on the model we discussed the influence of magnetic bias to charging equipment,and showed the importance of study on magnetic bias for electric vehicle charging equipment.We supposed several factors of electric vehicle charging equipment which may cause magnetic bias,and then derived the relationship between these factors and magnetic bias from mathematical formula.A conclusion is drawn that the parameters asymmetry of IGBT and the leakage inductance of transformer may cause or aggravate magnetic bias,and both the blocking capacitor and the primary winding’s resistance of power transformer have inhibition for charging equipment’s magnetic bias.According to the conclusion,we put forward the hardware design principles of electric vehicle charging equipment to inhibit magnetic bias,and the feasibility is validated by the simulation.