bstract: As mentioned in my previous blog on solar grid interactive inverters, giridaran-solar there are various issues involved with solar grid inverter for Indian conditions. Now in this blog I will be discussing more about the issues and methods to integrate/synchronize a grid connected inverter with diesel generator during a power cut/grid failure. In states like Tamil Nadu we have power-cuts every day, so the solar rooftop owner will try to consume all the power generated from solar and reduce its dependence on diesel generators.
The inverters do not start without the reference voltage and frequency, so during this islanding condition the rooftops owners cannot use their solar power generated. The owners usually consider solar as a backup for power cuts and also consider payback by selling excess generated. Now the only solution in the market is the hybrid inverters, but these are very expensive compared to normal grid inverters. But what about installations with existing grid inverters? Most of the rooftop owners are not aware of these islanding conditions and the EPC vendors just install existing grid inverters without any alteration proposed below.