Motor driving device and air conditioner including the same

Patent metadata

Field	Value
Publication number	US-9793787-B2
Application number	US-201414566368-A
Country	US
Kind code	B2
Filing date	Dec 10, 2014
Priority date	Dec 10, 2013
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

A motor driving device and an air conditioner including the same are disclosed. The disclosed motor driving device includes a multi-level converter to receive AC power, thereby outputting multi-level power, the multi-level converter including plural diodes and plural switching elements, plural capacitors for storing the multi-level power from the multi-level converter, and a gate drive signal generator to generate gate drive signals for the switching elements of the multi-level converter. The gate drive signal generator includes a gate drive power source to supply a gate drive voltage, a gate driver to generate the gate drive signals, using the gate drive voltage, a gate capacitor connected to both terminals of the gate driver, and a gate switching element connected between one end of the gate capacitor and one end of one of the plural capacitors. Accordingly, gate drive signals for the multi-level converter can be generated.

First claim

What is claimed is:

1. A motor driving device comprising:
rectifier having a plurality of diodes coupled in at least one of serially or in parallel;
a plurality of transistors to control an operation of the plurality of diodes;
a plurality of capacitors to store energy based an output of the rectifier; and
a gate signal generator to generate gate drive signals for the transistors, wherein the gate drive signal generator includes:
a gate driver to generate gate drive signals based on a gate drive voltage from a gate drive power source,
a gate capacitor coupled to both terminals of the gate driver,
a switch coupled between one terminal of the gate capacitor and one of the plurality of capacitors; and
a diode and a resistor connected between another terminal of the gate capacitor and the gate drive power source, the diode preventing a backflow of current to the gate drive power source,
wherein the one of the plurality of capacitors includes one terminal that is floated and is electrically connected to one terminal of the switch.

2. The motor driving device according to claim 1 , wherein
when the switch is turned on, the gate capacitor is configured to store energy based on the gate drive voltage, and
when the switch is turned off, the gate driver generates the gate drive signals using the energy stored in the gate capacitor.

3. The motor driving device according to claim 2 , wherein the switch is turned on when all of the plurality of transistors are turned off.

4. The motor driving device according to claim 1 , wherein the gate signal generator further includes a resistor coupled to the gate capacitor and a terminal configured for connection a gate drive voltage.

5. The motor driving device according to claim 1 , wherein each of the transistors is connected to a neutral node among the plurality of capacitors.

6. The motor driving device according to claim 1 , further comprising:
an inverter to provide AC power using the energy stored in the plurality of capacitors; and
an inverter controller to control the inverter.

7. The motor driving device according to claim 1 , further comprising a plurality of inductors configured to be coupled between an AC power source and the rectifier.

8. The motor driving device of claim 1 , wherein the plurality of transistors comprises first, second and third transistors, the plurality of diodes comprises a first pair of diodes coupled in series, a second pair of diodes coupled in series, and a third pair of diodes coupled in series, the first pair, second pair and third pair being coupled in parallel, wherein a first node between the first pair of diodes is coupled to the first transistor, a second node between the second pair of diodes is coupled to the second transistor, and a third node between the third pair of diodes is coupled to the third transistor.

9. An air conditioner comprising:
a compressor to compress a refrigerant;
a heat exchanger to perform heat exchange, using the compressed refrigerant; and
a compressor motor driving device to drive a motor equipped in the compressor, wherein the compressor motor driving device includes
a rectifier having a plurality of diodes coupled in at least one of serially or parallel;
a plurality of transistors to control an operation of the plurality of diodes;
a plurality of capacitors to store energy based an output of the rectifier; and
a gate drive signal generator to generate gate drive signals for the transistors, wherein the gate drive signal generator includes:
a gate driver to generate gate drive signals based on a gate drive voltage,
a gate capacitor coupled to both terminals of the gate driver,
a switch coupled between one terminal of the gate capacitor and one of the plurality of capacitors; and
a diode and a resistor connected between another terminal of the gate capacitor and a terminal of the gate drive power source,
wherein the diode prevents backflow of a current to the gate drive power source, and
wherein one terminal of one of the plurality of capacitors is floated, and the one terminal of one of the plurality of capacitors is connected electrically to one terminal of the switch.

10. The air conditioner according to claim 9 , wherein:
when the switch is turned on, the gate capacitor is configured to store energy based on the gate drive voltage, and
when the switch is turned off, the gate driver generates the gate drive signals using the energy stored in the gate capacitor.

11. The air conditioner according to claim 10 , wherein the switch is turned on when all of the plurality of transistors are turned off.

12. The air conditioner according to claim 9 , further comprising:
an inverter to provide AC power using the energy stored in the plurality of capacitors; and
an inverter controller to control the inverter.

13. The air conditioner according to claim 9 , wherein the plurality of transistors comprises first, second and third transistors, the plurality of diodes comprises a first pair of diodes coupled in series, a second pair of diodes coupled in series, and a third pair of diodes coupled in series, the first pair, second pair and third pair being coupled in parallel, wherein a first node between the first pair of diodes is coupled to the first transistor, a second node between the second pair of diodes is coupled to the second transistor, and a third node between the third pair of diodes is coupled to the third transistor.

14. A motor driving device comprising:
an AC/DC converter;
a plurality of capacitors to store energy based on an output from the AC/DC converter; and
a converter controller to control the operation of the AC/DC converter,
wherein the converter controller includes:
a switch connected to a floated terminal of one of the plurality of capacitors,
a gate capacitor for storing energy based on a gate drive voltage,
a gate driver to generate the gate drive signals, using the energy stored in the gate capacitor, and
a diode and a resistor connected between a terminal of the gate capacitor and a terminal of the gate drive power source,
wherein the diode prevents backflow of a current to the gate drive power source, and
wherein the floated terminal of one of the plurality of capacitors is connected electrically to one terminal of the switch.

15. The motor driving device according to claim 14 , wherein:
the energy is stored in the gate capacitor when the switch is turned on; and
the gate driver generates the gate drive signals, which is based on the gate drive voltage, using the energy stored in the gate capacitor, when the switch is turned off.

16. The motor driving device according to claim 15 , wherein the switch is turned on when all switching elements configured to be controlled by the gate drive signals in the AC/DC converter are turned off.

17. The motor driving device according to claim 14 , wherein the converter controller further includes a resistor connected to the gate capacitor and a terminal of the gate drive power source.

18. The motor driving device according to claim 14 , wherein each of the plural switching elements in the AC/DC converter is connected to a virtual neutral point among the plural capacitors.

19. The motor driving device according to claim 14 , wherein AC/DC converter comprises:
a 3-phase rectifier; and
a plural switching elements each connected between the 3-phase rectifier and a virtual neutral point among the plural capacitors.

Assignees

• Lg Electronics Inc

Inventors

• Cho Wonwoo
• Park Gwigeun

Classifications

• H02M1/08 Primary

  Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters · CPC title

• H02M7/483 Primary

  Converters with outputs that each can have more than two voltages levels · CPC title

• H02P6/14

  Electronic commutators · CPC title

• H02M5/44

  using discharge tubes or semiconductor devices to convert the intermediate DC into AC · CPC title

• H02M2001/0006

  Electricity · mapped topic