Power flow direction detector

摘要

A power flow detector for connection to power supply lines includes a phase difference-to-pulse width converter for producing pulse signals for which the pulse width corresponds to the phase difference between the load voltage and load current of the power supply lines. The output of the phase difference-to-pulse width converter is integrated and the integrated voltage is compared with a reference voltage. The power flow direction is determined by whether the integrated voltage is larger than or smaller than the reference voltage.