Powerless Insulated DC–AC Voltage Measurement by Photovoltaic Energy Harvesting from a P–N Collector–Base Junction in an Opto-Insulator

This paper presents a simple and inexpensive powerless electrical insulated voltage measuring sensor using optical couplers for AC and DC voltage measurement, by harvesting the optical photovoltaic energy from a P–N collector–base junction in an opto-insulator to generate an output voltage proportional to the voltage input. A voltage transducer was built with a low-cost opto-insulator circuit and tested to evaluate the voltage measurement capabilities. The system proved to operate properly for AC power line and DC voltages and switching voltages with a bandwidth of 10 kHz. Applications for the powerless insulated DC–AC voltage sensor are in power electronics, voltage measurement, and control.