Electric power converter

Patent metadata

Field	Value
Publication number	US-2016156302-A1
Application number	US-201314902983-A
Country	US
Kind code	A1
Filing date	Sep 27, 2013
Priority date	Sep 27, 2013
Publication date	Jun 2, 2016
Grant date	—

Abstract

The present invention relates to a rush current limiting circuit in which a series circuit consisting of an inductor and a resistor for detecting a current is connected between a power source and a first semiconductor switch, in which there is provided a second semiconductor switch whose inter-output-terminal voltage is controlled by the voltage across the series circuit consisting of the inductor and the resistor for detecting a current, and in which the inter-output-terminal voltage of the second semiconductor switch controls the inter-control-terminal voltage of the first semiconductor switch so as to limit a current to a load; the present invention relates also to an electric power converter including the rush current limiting circuit.

First claim

1 - 5 . (canceled)

6 . An electric power converter comprising:
an electric-power conversion unit that has a three-phase bridge circuit in which each of arms is formed of a power semiconductor switch, in which a DC power source is connected between DC terminals, and in which each of armature windings of a rotating electric machine is connected between corresponding AC terminals; and a control circuit that controls the power semiconductor switches, wherein there are provided a motor operation mode in which the rotating electric machine is made to operate as a motor and an electric-power-generator operation mode in which the rotating electric machine is made to operate as an electric power generator, wherein in the motor operation mode, the power semiconductor switches are controlled by the control circuit in such a way that the electric-power conversion unit converts DC electric power from the DC power source into AC electric power, and in the electric-power-generator operation mode, the power semiconductor switches are controlled by the control circuit in such a way that the electric-power conversion unit converts AC electric power outputted from the rotating electric machine, which is driven by a driving source so as to generate electric power, into DC electric power, wherein the control circuit is supplied with an operational power source from the DC power source through a positive electrode of DC terminals of the electric-power conversion unit, by way of a rush current limiting circuit, and in the electric-power-generator operation mode, the control circuit controls the power semiconductor switches in such a way that one pulse is energized in synchronization with an electric-angular cycle of a rotor of the rotating electric machine, and wherein the rush current limiting circuit has a series circuit that is connected between the DC power source and the first semiconductor switch and is formed of an inductor and a current detection resistor that are connected in series with each other and a second semiconductor switch whose inter-output-terminal voltage is controlled by a voltage across the series circuit; and based on an inter-output-terminal voltage of the second semiconductor switch, the rush current limiting circuit controls an inter-control-terminal voltage of the first semiconductor switch so as to limit an electric current to the control circuit.

7 . The electric power converter according to claim 6 , wherein a circulation diode is connected in parallel with the inductor or the series circuit.

8 . The electric power converter according to claim 6 , further including a voltage limiting circuit that turns on the second semiconductor switch when a voltage applied to the control circuit exceeds a predetermined value.

9 . The electric power converter according to claim 6 , further including a voltage limiting circuit that turns on the second semiconductor switch when the voltage of the DC power source exceeds a predetermined value.

10 . The electric power converter comprising:
an electric-power conversion unit that has a three-phase bridge circuit in which each of arms is formed of a power semiconductor switch; and a control circuit that controls operation of the power semiconductor switches, wherein there is provided a motor operation mode in which the three-phase bridge circuit to be controlled by the control circuit converts DC electric power from a DC power source into AC electric power and supplies electric power to a rotating electric machine so that the rotating electric machine is made to operate as a motor, and there is provided an electric-power-generator operation mode in which the three-phase bridge circuit converts AC electric power generated by the rotating electric machine, which is driven by a driving source, into DC electric power and supplies electric power to the DC power source so that the rotating electric machine is made to operate as an electric power generator, wherein in the motor operation mode in which the rotating electric machine is made to operate as a motor, the control circuit controls the power semiconductor switches by use of a one-pulse energization method that is in synchronization with an electric-angular cycle of a rotor of the rotating electric machine, and wherein the control circuit is supplied with an operational power source from a positive electrode of DC terminals of the electric power converter, by way of the rush current limiting circuit according to claim 6 .

Assignees

• Mitsubishi Electric Corp

Inventors

• Asai Takamasa

Classifications

• H02H9/001

  limiting speed of change of electric quantities, e.g. soft switching on or off (progressive control of electronic switches for eliminating interferences H03K17/16) · CPC title

• H02P9/02

  Details {of the control} · CPC title

• H02P29/027 Primary

  the fault being an over-current · CPC title

• H02P27/08

  with pulse width modulation · CPC title

• H02P27/06

  using DC to AC converters or inverters (H02P27/05 takes precedence) · CPC title