Solar inverters play a major role in converting solar power into usable electricity. To keep them safe and reliable, an important feature called the Insulation Monitoring Device (IMD) is used. Over time, the insulation of cables and components in a Solar PV inverter system can get damaged due to rain, dust, heat, or ageing. When insulation becomes weak, leakage current can flow to the ground. This can cause safety risks, inverter faults, or even fire hazards. The Insulation Monitoring Device (IMD) continuously checks the insulation resistance between the solar panels and the earth. If the insulation level drops below a safe limit, the inverter gives an alarm or shuts down automatically to prevent damage and accidents. IMD helps in protecting people from electric shock, preventing fire and equipment damage, improving system reliability, and meeting safety standards. This work is done at NCPRE by student Srivardhan Sarma Machavolu under the guidance of Prof. Sandeep Anand.
Flowchart of General IMD working.