Comprehensive detection and electric protection device for power frequency and variable frequency power supplies

The invention discloses a comprehensive detection and electric protection device for power frequency and variable frequency power supplies. The device comprises a current detection conversion circuit, a precision rectifying and filtering circuit, a signal processing circuit, a fault signal processing alarm circuit, a time control circuit and a system start control circuit, wherein the current detection conversion circuit detects a variable frequency or power frequency power supply signal, converts the power supply signal into a voltage signal with the same frequency and outputs the voltage signal to the precision rectifying and filtering circuit; the precision rectifying and filtering circuit outputs the rectified and filtered signal to the signal processing circuit; the signal processing circuit outputs the processed signal to the fault signal processing alarm circuit; the signal input end of the system start control circuit is connected with a working detection power supply of a frequency converter; and the signal output end of the system start control circuit is connected with the power supply control end of each circuit. The device can perform circuit protection on the power supplies accurately and adapts to working frequency ranges of multiple kinds of electric equipment, a user immediately masters the condition of a fault circuit, and the power supplies of the electric equipment are overhauled and maintained.