Air conditioner controlling prheating power of compressor and mechanism providing preheating power for compressor

Patent metadata

Field	Value
Publication number	US-9496816-B2
Application number	US-201013514066-A
Country	US
Kind code	B2
Filing date	Mar 23, 2010
Priority date	Dec 17, 2009
Publication date	Nov 15, 2016
Grant date	Nov 15, 2016

Abstract

An air conditioner equipped with a compressor, an indoor heat exchanger and an outdoor heat exchanger includes: an inverter circuit that drives a motor of the compressor; an inverter-power detecting unit that detects power of the inverter circuit; a PWM-signal generating unit that inverter-current detecting unit generates PWM signals for controlling the inverter circuit; a voltage-command-value generating unit that outputs voltage command values to the PWM-signal generating unit; and an accumulation detecting unit that detects accumulation of a liquid refrigerant within the compressor and outputs a detection result to the voltage-command-value generating unit, wherein when accumulation of a liquid refrigerant within the compressor is detected, the voltage-command-value generating unit outputs the voltage command value so that power of the inverter circuit has a predetermined power value.

First claim

The invention claimed is:

1. An air conditioner including a compressor, an indoor heat exchanger, and an outdoor heat exchanger, the compressor having a motor in which an inductance value is different depending on a position of a rotor, the air conditioner comprising:
an inverter circuit that drives the motor of the compressor;
an inverter-power detecting unit that detects power of the inverter circuit;
a PWM-signal generating unit that generates PWM signals for controlling the inverter circuit;
a voltage-command-value generating unit that outputs voltage command values to the PWM-signal generating unit; and
an accumulation detecting unit that detects accumulation of a liquid refrigerant within the compressor and outputs a detection result to the voltage-command-value generating unit, wherein
when accumulation of a liquid refrigerant within the compressor is detected, the voltage-command-value generating unit outputs the voltage command values so that power of the inverter circuit has a predetermined power value.

2. The air conditioner according to claim 1 , wherein
the inverter-power detecting unit includes
an inverter-voltage detecting unit that detects an input voltage of the inverter circuit, and
an inverter-current detecting unit that detects an input current of the inverter circuit, and
when accumulation of a liquid refrigerant within the compressor is detected, the voltage-command-value generating unit outputs the voltage command values based on the input voltage of the inverter circuit and the input current of the inverter circuit so that power of the inverter circuit has a predetermined power value.

3. The air conditioner according to claim 1 , wherein
the inverter-power detecting unit includes an inverter-current detecting unit that detects an output current of the inverter circuit, and
when accumulation of a liquid refrigerant within the compressor is detected, the voltage-command-value generating unit outputs the voltage command values based on the output current of the inverter circuit so that power of the inverter circuit has a predetermined power value.

4. The air conditioner according to claim 1 , wherein
the inverter-power detecting unit includes
an inverter-voltage detecting unit that detects an alternating-current input voltage of the inverter circuit, and
an inverter-current detecting unit that detects an alternating-current input current of the inverter circuit, and
when accumulation of a liquid refrigerant within the compressor is detected, the voltage-command-value generating unit outputs the voltage command values based on the alternating-current input voltage of the inverter circuit and the alternating-current input current of the inverter circuit so that power of the inverter circuit has a predetermined power value.

5. The air conditioner according to claim 1 , wherein an output frequency of the voltage-command-value generating unit is higher than an operating frequency of the inverter circuit during a compressing operation.

6. The air conditioner according to claim 1 , wherein an output frequency of the voltage-command-value generating unit is higher than an audible range.

7. The air conditioner according to claim 1 , wherein an output frequency of the voltage-command-value generating unit is lower than an upper limit of a switching frequency of switching elements that constitute the inverter circuit.

8. The air conditioner according to claim 1 , wherein the motor is of an interior permanent magnet configuration.

9. The air conditioner according to claim 1 , wherein the motor is a concentrated winding motor.

10. The air conditioner according to claim 1 , wherein the compressor has a scroll mechanism.

11. The air conditioner according to claim 1 , wherein when an operating frequency of the inverter circuit exceeds 10 kilohertz, the predetermined power value is set to be equal to or lower than 50 watts.

12. The air conditioner according to claim 1 , wherein the voltage-command-value generating unit changes the predetermined power value according to an accumulation state detected by the accumulation detecting unit.

Assignees

• Hatakeyama Kazunori
• Sakanobe Kazunori
• Matsushita Shinya
• Makino Tsutomu
• Mitsubishi Electric Corp

Inventors

• Hatakeyama Kazunori
• Sakanobe Kazunori
• Matsushita Shinya
• Makino Tsutomu

Classifications

• F25B2600/021

  Inverters therefor · CPC title

• F25B2700/04

  Refrigerant level · CPC title

• H02P27/04 Primary

  using variable-frequency supply voltage, e.g. inverter or converter supply voltage · CPC title

• F25B49/025

  Motor control arrangements · CPC title

• Y02B30/741

  Cross-Sectional Technologies · mapped topic