Patent ID: 9179504
Filing Date: 2015-11-03
Classification: H02M,H05B

Abstract:
1. A power converter comprising: a converter circuit that transforms an input power-supply voltage to a transformed output voltage, the converter circuit including a switch that is switched by a converter gate signal; a capacitor smoothing the output voltage output by the converter circuit; an inverter circuit that converts a direct-current voltage smoothed by the capacitor into an alternating-current voltage and supplies electric power to a load; a current sensor that detects current that is output by the capacitor and is input directly to the inverter circuit without passing through any other component; a frequency detector that detects a frequency of a frequency component having a maximum amplitude among frequency components of the current flowing from the capacitor to the inverter circuit, based on a detection result of the current sensor; a phase detector that detects a phase of the frequency component having the maximum amplitude among the frequency components of the current flowing from the capacitor to the inverter circuit, and detects a time when each amplitude of the frequency component having the maximum amplitude is zero, based on the detection result of the current sensor; a carrier oscillator that generates a pulse width modulation carrier signal; a carrier signal controller that controls frequency and phase of the pulse width modulation carrier signal generated by the carrier oscillator, and causes the carrier oscillator to generate a corrected pulse width modulation carrier signal by controlling the frequency and the phase of the pulse width modulation carrier signal generated by the carrier oscillator, based on a detection result of the frequency detector and a detection result of the phase detector, the corrected carrier signal having a frequency that matches the frequency detected by the frequency detector and a rise time synchronized to the time detected by the phase detector; and a gate drive circuit that generates the converter gate signal based on the corrected phase-modulated carrier signal, and inputs the converter gate signal to the switch of the converter circuit to control switching of the switch of the converter circuit, wherein the convertor circuit transforms the input power supply voltage to the transformed output voltage due to the convertor gate signal switching of the switch of the converter circuit.