Patent ID: 7483279

Claim:
An apparatus for detecting phase currents of an inverter, comprising: a switch section for converting a direct current power into an alternating current power and providing the alternating current power to a load as a plurality of upper switching elements and lower switching elements are turned-on according to a plurality of pulse width modulation signals; a plurality of current detecting resistors coupled between the plurality of lower switching elements and a ground, respectively; a plurality of analog/digital converters for converting voltages of the plurality of current detecting resistors into digital signals; a triangular wave generator for generating a triangular wave having a predetermined time period; a current detection controller for generating three-phase sine wave voltages, for comparing the generated three-phase sine wave voltage with a reference threshold voltage, and for varying the three-phase sine wave voltage according to the compared result to control a detection of the phase currents; a pulse width modulation signal generator for comparing the three-phase sine wave voltages from the current detection controller with a voltage of the triangular wave generated by the triangular wave generator to generate and output the plurality of pulse width modulation signals to the switch section; and a phase current detector for detecting output signals of the plurality of analog/digital converters as the phase currents according to a control of the current detection controller.