Study and implementation of grounding insulation resistance detection system for the solar inverter

Grounding insulation resistance detection is of great importance for the solar inverter. A novel scheme of grounding insulation resistance detection system based on switch-controlled bridge circuit for the solar inverter was proposed in the paper. By controlling the bridge circuit, linear equations in respect of insulation resistances can be established, and the values of insulation resistances can be obtained by solving the equations. The hardware circuits and the software algorithm were designed and implemented. The experimental results show that the detection system worked well and the detection result was accurate.