Motor driving apparatus and home appliance including the same

Patent metadata

Field	Value
Publication number	US-9806654-B2
Application number	US-201615238894-A
Country	US
Kind code	B2
Filing date	Aug 17, 2016
Priority date	Aug 19, 2015
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

Disclosed herein are a motor driving apparatus and a home appliance including the same. The motor driving apparatus includes a direct current (DC) link capacitor, an inverter, a DC link voltage detector, and a controller. The controller controls rheostatic braking to be performed in order to stop the motor, performs bootstrap operation of gate terminals of the upper arm switching elements of the inverter during a first period for starting the motor, and determines whether the motor stops during the first period based on the DC voltage detected by the DC link voltage detector or the output current detected by the output current detector. Accordingly, it is possible to conveniently determine whether the motor stops in the sensorless type motor driving apparatus.

First claim

What is claimed is:

1. A motor driving apparatus comprising:
a capacitor configured to store a charge;
an inverter including a plurality of first switching elements and a plurality of second switching elements and configured to convert the charge stored in the capacitor into alternating current (AC) voltage and to output the AC voltage to a motor;
a voltage detector configured to detect a voltage associated with the capacitor;
a current detector provided between the capacitor and the inverter and configured to detect a current flowing between the capacitor to the inverter; and
a controller configured to control the inverter based on the voltage detected by the voltage detector and the current detected by the current detector, wherein the controller controls the inverter to perform braking of the motor, performs a bootstrap operation of the plurality of first switching elements of the inverter after performing the braking and during a first period for starting the motor, determines whether the motor stops during the first period based on at least one of the voltage detected by the voltage detector or the current detected by the current detector, and further controls the inverter based on determining whether the motor stops during the first period.

2. The motor driving apparatus according to claim 1 , wherein the controller determines that the motor has not stopped during the first period when at least one of a change in the voltage detected by the voltage detector is equal to or greater than a first predetermined value or a peak value of the voltage detected by the voltage detector is equal to or greater than a first level, and the controller further controls the inverter to perform addition braking based on determining that the motor has not stopped during the first period.

3. The motor driving apparatus according to claim 1 , wherein the controller determines that the motor stops during the first period when at least one of a change in the voltage detected by the voltage detector is less than a first predetermined value or a peak value of the voltage detected by the voltage detector is less than a first level, and the controller further controls the inverter to perform an alignment of the motor after the first period based on determining that the motor stops during the first period.

4. The motor driving apparatus according to claim 1 , wherein the controller determines that the motor has not stopped during the first period when a change in the current detected by the current detector is equal to or greater than a second predetermined value or a peak value of the current detected by the current detector is equal to or greater than a second level, and the controller further controls the inverter to perform additional braking based on determining that the motor has not stopped during the first period.

5. The motor driving apparatus according to claim 1 , wherein the controller determines that the motor stops during the first period when at least one of a change in the current detected by the current detector is less than a second predetermined value or a peak value of the current detected by the current detector is less than a second level, and the controller further controls the inverter to perform an alignment of the motor after the first period based on determining that the motor stops during the first period.

6. The motor driving apparatus according to claim 1 , further comprising:
a first gate driver connected to the plurality of first switching elements;
a second gate driver connected to the plurality of second switching elements; and
a first gate capacitor connected to the first gate driver and a second gate capacitor connected to the second gate driver, the first gate capacitor and the second gate capacitor being configured to store a gate drive charge,
wherein the controller:
turns off the plurality of first switching elements and the plurality of second switching elements to cause the second gate capacitor to store the gate drive charge, or
turns off the plurality of first switching elements and turns on the plurality of second switching elements to cause the first gate capacitor to store the gate drive charge.

7. The motor driving apparatus according to claim 1 , wherein the controller determines whether the motor stops during the first period based on the voltage detected by the voltage detector or the current detected by the current detector, while the plurality of first switching elements of the inverter are turned off and the plurality of second switching elements are turned on.

8. A motor driving apparatus comprising:
a capacitor configured to store a charge;
an inverter including a plurality of first switching elements and a plurality of second switching elements and configured to convert the charge stored in the capacitor into an alternating current (AC) voltage and to output the converted AC voltage to a motor;
a voltage detector configured to detect a voltage associated with the capacitor;
a current detector provided between the capacitor and the inverter and configured to detect a current flowing toward the motor; and
a controller configured to control the inverter based on the voltage and the current, wherein the controller determines whether the motor is moving while restarting the motor when at least one of:
a change in the voltage detected by the voltage detector is equal to or greater than a first predetermined value,
a peak value of the voltage detected by the voltage detector is equal to or greater than a first level,
a change in the current detected by the current detector is equal to or greater than a second predetermined value, or
a peak value of the current detected by the current detector is equal to or greater than a second level, and
wherein the controllers further controls the inverter to stop the motor based on determining whether the motor is moving.

9. A home appliance comprising:
a motor;
a display;
a capacitor configured to store a charge;
an inverter including a plurality of first switching elements and a plurality second switching elements and configured to convert the charge stored in the capacitor into an alternating current (AC) voltage and to output the AC voltage to the motor;
a voltage detector configured to detect a voltage associated with the DC link capacitor;
a current detector provided between the capacitor and the inverter and configured to detect a current flowing between the capacitor and the inverter; and
a controller configured to control the inverter based on the current and the voltage, wherein the controller controls the inverter to apply braking to the motor, determines whether the motor stops during a first period after applying the braking based on the voltage detected by the voltage detector or the current detected by the current detector, and controls the inverter to restart the motor during the first time period based on determining whether the motor stops.

10. The home appliance according to claim 9 , wherein the controller determines that the motor is not stopped when at least one of a change in the voltage detected by the voltage detector is equal to or greater than a first predetermined value or a peak value of the voltage detected by the voltage detector is equal to or greater than a first level, and wherein the controller applies additional braking in order to stop the motor based on determining that the motor is not stopped.

11. The home appliance according to claim 10 , wherein the controller determines that the motor stops when change in the voltage detected by the voltage detector is less than the first predetermined value or the peak value of the voltage detected by the voltage detector is less

Assignees

• Lg Electronics Inc

Inventors

• Jung Hansu
• Jang Hoyong
• Cho Seokhee

Classifications

• H02P6/20

  Arrangements for starting (H02P6/08 takes precedence) · CPC title

• H02P3/22

  by short-circuit or resistive braking · CPC title

• D06F34/18

  Condition of the laundry, e.g. nature or weight · CPC title

• H02P27/06

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

• H02P6/24

  Arrangements for stopping · CPC title