中型功率光伏并网逆变器电磁辐射骚扰解决方法

Solution of Medium Power Grid-connected PV Inverter Radiation Emission

为了提高光伏并网逆变器的效率,逆变器中的功率半导体器件往往采用较快的开关速度以降低其开关损耗。但提高开关速度会导致电路中的di/dt增大,产生的干扰相应增加,造成逆变器的传导骚扰、电磁辐射骚扰很难通过相应的标准。首先,以中型功率光伏并网逆变器为例,分析并查找辐射骚扰源;然后,通过对机箱进行屏蔽,降低电源线共模电流等方法,使逆变器的电磁辐射骚扰通过标准限值要求。

In order to improve the efficiency of Power Grid-connected PV Inverter, semiconductor devices tend to use a faster switching speed to reduce the switching losses. Increase the switching speed, resulting in the increase of di/dt in the circuit, and the corresponding increase of the EMC interference. It is difficult to pass the relevant standards for the conduction emission and the radiation emission. This paper is taken medium power grid-connected PV Inverter as an example. Analysis and find the source of radiation emission, take special measures such as shielding, reduce common mode current of power line, and finally meet standard requirements.