I am working on a solar energy project and I'm using a 10 panel array. For monitoring purposes I'm using a combiner device which tracks various data parameters like current, voltage and temperature. This combiner device should be able to withstand a 50A current and give current measurements with 0.5% error rating. Now I have already tested 2 different methods and faced the corresponding problems.
- Hall effect based sensors: For the sensor I selected, I was still getting 1% to 2% percent error in ideal conditions and the sensor was going out of my budget,too.
- Shunt resistor: I was able to find some shunts with 0.5% error, but the problem was with the dissipated heat. On longer testing cycles the Shunt PCB was getting extremely hot. I tried different design techniques:changing shunts, track width and others. Still,on long testing cycles.the heat dissipation was beyond acceptable for my application.(I've added an image of the same below)
Now on searching for other techniques online, I found some using an inductor, current transformer, transistor. But I have no experience or knowledge of their capabilities. I need help to choose the best technique for current measurement with 50Amps and 0.5% error margin and also not too expensive. Thank you!