An inverter includes an inverter circuit; an alternating current filter, where an input port of the alternating current filter is connected to an output port of the inverter circuit; an alternating current electromagnetic interference (EMI) filter; and a first alternating current switch, connected between an output port of the alternating current filter and an input port of the alternating current EMI filter. The first split capacitor is disposed between the first alternating current switch and the input port of the alternating current EMI filter; and when the first alternating current switch is turned off, the first split capacitor is disconnected from the output port of the alternating current filter, and the first split capacitor is connected to a circuit in which an alternating current system connected to the output port of the alternating current EMI filter is located, to suppress harmonic distortion of the alternating current system.

An inverter includes an inverter circuit; an alternating current filter, where an input port of the alternating current filter is connected to an output port of the inverter circuit; an alternating current electromagnetic interference (EMI) filter; and a first alternating current switch, connected between an output port of the alternating current filter and an input port of the alternating current EMI filter. The first split capacitor is disposed between the first alternating current switch and the input port of the alternating current EMI filter; and when the first alternating current switch is turned off, the first split capacitor is disconnected from the output port of the alternating current filter, and the first split capacitor is connected to a circuit in which an alternating current system connected to the output port of the alternating current EMI filter is located, to suppress harmonic distortion of the alternating current system.

An integrated circuit for a power supply circuit. The integrated circuit includes an oscillator circuit configured to output an oscillator voltage that rises with a predetermined slope from a first voltage, upon an inductor current of the power supply circuit becoming smaller than a first predetermined value, an error voltage output circuit configured to output an error voltage corresponding to a difference between a reference voltage and a feedback voltage corresponding to the output voltage, a drive circuit configured to turn on and off a transistor of the power supply circuit respectively upon the inductor current becoming smaller than the first predetermined value, and upon the oscillator voltage reaching a second voltage that is based on the error voltage, and an output circuit configured to change the first and/or second voltage based on a rectified voltage obtained by full-wave rectification of the AC voltage, and to output the changed voltage.

An integrated circuit for a power supply circuit. The integrated circuit includes an oscillator circuit configured to output an oscillator voltage that rises with a predetermined slope from a first voltage, upon an inductor current of the power supply circuit becoming smaller than a first predetermined value, an error voltage output circuit configured to output an error voltage corresponding to a difference between a reference voltage and a feedback voltage corresponding to the output voltage, a drive circuit configured to turn on and off a transistor of the power supply circuit respectively upon the inductor current becoming smaller than the first predetermined value, and upon the oscillator voltage reaching a second voltage that is based on the error voltage, and an output circuit configured to change the first and/or second voltage based on a rectified voltage obtained by full-wave rectification of the AC voltage, and to output the changed voltage.

A power conversion device includes: a power conversion circuit connected to a direct-current power supply and a power system and configured to perform conversion between direct-current power and alternating-current power; a phase-locked loop circuit configured to output a phase instruction value based on a system alternating-current voltage phase of the power system; and a control circuit configured to control the power conversion circuit based on the phase instruction value from the phase-locked loop circuit. The phase-locked loop circuit includes: a phase difference calculation section configured to calculate a phase difference in a predetermined cycle, the phase difference representing a deviation of the phase instruction value from the system alternating-current voltage phase of the power system; a phase difference correction section; and a phase instruction value generation section configured to output the phase instruction value based on an output of the phase difference correction section.

An apparatus for converting power of a fuel cell for power generation to remove an open voltage of the fuel cell and a method thereof are provided. A power converter converts and supplies power generated by the fuel cell to a system or load. A controller maintains a current linkage to the system or load to reduce an open circuit voltage (OCV) of the fuel cell, after power generation of the fuel cell is ended. The apparatus removes the OCV of the fuel cell to reduce performance and life of the fuel cell, when the fuel cell is stopped.

An apparatus for converting power of a fuel cell for power generation to remove an open voltage of the fuel cell and a method thereof are provided. A power converter converts and supplies power generated by the fuel cell to a system or load. A controller maintains a current linkage to the system or load to reduce an open circuit voltage (OCV) of the fuel cell, after power generation of the fuel cell is ended. The apparatus removes the OCV of the fuel cell to reduce performance and life of the fuel cell, when the fuel cell is stopped.

A power module for operating an electric vehicle drive, comprising: numerous power switches, each of which has a power semiconductor; a control electronics for controlling the numerous power switches to generate an output current based on an input current; wherein the control electronics also comprises a temperature unit configured to detect an operating voltage and operating current in the power semiconductor, and determine the temperature of the power semiconductor based on the operating voltage and operating current.

A power module for operating an electric vehicle drive, comprising: numerous power switches, each of which has a power semiconductor; a control electronics for controlling the numerous power switches to generate an output current based on an input current; wherein the control electronics also comprises a temperature unit configured to detect an operating voltage and operating current in the power semiconductor, and determine the temperature of the power semiconductor based on the operating voltage and operating current.

A load abnormality detecting circuit for an inverter to detect abnormality of a load during an operation of the inverter which has a self-arc-extinguishing element as a switching element and a phase synchronizing loop controlling an output frequency to be a resonance frequency of the load, the load abnormality detecting circuit includes a phase shift detection part that detects a phase shift between a gate voltage signal controlling ON/OFF of the self-arc-extinguishing element and an output current of the inverter which is applied to the load, and that sends a first abnormal load signal based on the phase shift.