Inverter control apparatus

Patent metadata

Field	Value
Publication number	US-10411630-B2
Application number	US-201815863248-A
Country	US
Kind code	B2
Filing date	Jan 5, 2018
Priority date	Mar 6, 2017
Publication date	Sep 10, 2019
Grant date	Sep 10, 2019

Abstract

The apparatus according to the present invention comprises a command voltage determination circuit section configured to determine a predetermined first compensation voltage as a command voltage upon initial startup and provide the command voltage to an inverter; a conversion circuit section configured to convert an output current of the inverter into a q-axis current on a synchronous reference frame; and a compensation voltage determination circuit section configured to determine a second compensation voltage based upon the q-axis current and to provide the second compensation voltage to the command voltage determination circuit section.

First claim

What is claimed is:

1. An apparatus for controlling an inverter for driving a motor, the apparatus comprising:
a command voltage determination circuit section that determines a predetermined first compensation voltage as a first command voltage upon initial startup and provides the first command voltage to the inverter;
a conversion circuit section that converts an output current of the inverter into a torque component current on a synchronous reference frame; and
a compensation voltage determination circuit section that determines a second compensation voltage based upon the torque component current and provides the second compensation voltage to the command voltage determination circuit section,
wherein the compensation voltage determination circuit section comprises:
a first amplifier that amplifies a predetermined rated torque component current by a first gain to output the amplified rated torque component current;
a subtractor that subtracts the amplified rated torque component current output from the first amplifier from the torque component current;
a comparator that compares an output of the subtractor with a predetermined reference current value to output a logic high output when the output of the subtractor is not less than the predetermined reference current value;
a multiplier that multiplies the output from the comparator by the torque component current to output the torque component current when an output of the comparator is a logic high output;
a low pass filter that attenuates a ripple component of the torque component current to output the torque component current from which ripple component is removed; and
a second amplifier that amplifies the torque component current output from the low pass filter with a second gain and outputs the amplified torque component current as the second compensation voltage.

2. The apparatus of claim 1 , wherein the command voltage determination circuit section is configured to provide, to the inverter, with a second command voltage determined by compensating the second compensation voltage to the first command voltage, after the first command voltage is provided to the inverter.

3. The apparatus of claim 1 , wherein the command voltage determination circuit section is configured to fix a target command voltage and output the fixed target command voltage when a command frequency of the inverter reaches a target frequency.

4. The apparatus of claim 1 , wherein the second gain corresponds to stator resistance.

Assignees

• Lsis Co Ltd

Inventors

• Byun Sunghoon

Classifications

• H02P1/28

  by progressive increase of voltage applied to primary circuit of motor · CPC title

• H02P1/028 Primary

  wherein the motor voltage is increased at low speed, to start or restart high inertia loads · CPC title

• H02P27/047

  V/F converter, wherein the voltage is controlled proportionally with the frequency · CPC title

• H02P27/08 Primary

  with pulse width modulation · CPC title

• H02P21/04 Primary

  specially adapted for very low speeds · CPC title