Patent attributes
In an embodiment, a current sensor unit includes: a rectification module, to convert an AC current to a pulsed DC current; a conversion module containing an energy storage element, to store energy based upon the pulsed DC current during a charging mode and generate a power supply current; a switching module, bypassed by the conversion module during the charging mode, and bypassing the conversion module during an energy release mode; a current sensor module, to detect a pulsed DC current; a control module, to acquire electrical energy from the power supply current, determine operation in the charging mode or energy release mode, and acquire a first detection value provided by the current sensor module; and a self-calibration module, to generate a current flowing through the current sensor module in a self-calibration process, the control module calibrating the first detection value based upon a second detection value of the current generated.