Refrigerator

• US 6,367,273 B2
• Filed: 04/13/2001
• Issued: 04/09/2002
• Est. Priority Date: 06/18/1998
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Takagi, Junichi, Nakamura, Hideyuki, Yoshida, Hideki, Kumakura, Hideo, Arakawa, Noriaki, Wakatabe, Takeshi, Ishii, Makoto
• Primary Examiner(s): Tanner, Harry B.
• Application Number:
  US09/833,556
• Publication Number:
  US 20010035018A1
• Time in Patent Office: 361 Days
• Field of Search: 622/30, 622/284, 622/281, 622/15, 622/29, 318/802, 318/801, 318/803, 363/40, 363/41, 363/42, 363/43
• US Class Current: 62/230
• CPC Class Codes: F25B 2600/021 Inverters therefor
• CPC Class Codes: F25B 49/025 Motor control arrangements
• CPC Class Codes: F25D 2400/30 Quick freezing
• CPC Class Codes: Y02B 30/70 Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Abstract

A refrigerator, having a motor for driving a compressor, an inverter for controlling the operation of the motor, a converter responsive to AC to perform a boosting function to supply DC of variable voltage to the inverter, converter control means for controlling the converter so that a plurality of DC voltages are outputted thereby and inverter control means for controlling the inverter in pulse width modulation each of the plurality of voltages. The lowest voltage among the plurality of voltages being a voltage which turns off the boosting function of the converter.

Claims

1. A refrigerator, comprising:

motor for driving a compressor;

an inverter for controlling the operation of said motor;

a converter responsive to AC to perform a boosting function to supply DC of variable voltage to said inverter;

converter control means for controlling said converter so that a plurality of DC voltages are outputted thereby; and

inverter control means for controlling said inverter in pulse width modulation each of said plurality of voltages;

the lowest voltage among said plurality of voltages being a voltage which turns off the boosting function of said converter.

2. A refrigerator, comprising:

motor for driving a compressor;

an inverter for controlling the operation of said motor;

a converter having a rectifier circuit for converting AC to DC and a boosting circuit for boosting a DC voltage and supplying the DC to said inverter;

boosting circuit control means for controlling said boosting circuit so that said converter can output a plurality of DC voltages; and

inverter control means for controlling said inverter using pulse width modulation of each of said plurality of voltages;

the lowest voltage among said plurality of voltages being an output voltage of the rectifier circuit of said converter.

3. A refrigerator, comprising:

a rectifier circuit for converting AC into DC;

a boosting chopper for boosting said DC;

a reactor provided between said rectifier circuit and said boosting chopper;

an inverter provided behind said boosting chopper for converting DC to AC;

a motor which is controlled by said inverter and which drives a compressor;

boosting chopper control means for controlling said boosting chopper so that the DC inputted to said inverter becomes DC of a plurality of kinds; and

inverter control means for controlling said inverter using the pulse width modulation of each of the plurality of types of DC voltages;

said reactor presenting a large inductance in a small current range and a small inductance in a large current range.

4. The refrigerator according to claim 3, wherein said reactor comprises coils wound around a ringed core having at least one gap.

5. A refrigerator, comprising:

motor for driving a compressor;

an inverter for controlling said motor;

a converter having a rectifier circuit for converting AC to DC and a boosting circuit for boosting a DC voltage and supplying DC to said inverter;

boosting circuit control means for controlling said boosting circuit so that said converter can output a plurality of DC voltages; and

inverter control means for controlling said inverter using pulse width modulation of each of said plurality of voltages;

said refrigerator further comprising;

first operating means for operating said motor in a speed range which is lower than a first rotating speed;

second operating means for driving said motor at a second speed which is greater than said first rotating speed;

wherein said plurality of DC voltages comprise three stages of voltages representing high, intermediate and low voltages;

said boosting chopper control means being arranged so that the three stages of high, middle and low voltages are selected corresponding to the rotating speed of said motor, said high voltage being selected when said second operating means is selected.

6. A refrigerator, comprising:

a motor for driving a compressor;

an inverter for controlling operation of said motor;

a converter having a rectifier circuit for converting AC to DC and a boosting circuit for boosting a DC voltage and supplying DC to said inverter;

boosting circuit control means for controlling said boosting circuit so that said converter can output a plurality of DC voltages; and

inverter control means for controlling said inverter using pulse width modulation of each of said plurality of voltages;

wherein

said plurality of DC voltages are selected based on a rotating speed command of said motor and an actual speed of rotation thereof.

7. A refrigerator, comprising:

motor for driving a compressor;

an inverter for controlling said motor;

a converter responsive to AC for supplying DC of variable voltage to said inverter;

said refrigerator further comprising;

means for setting the DC voltage supplied to said inverter at a value higher than the value converted from AC to DC.

8. A refrigerator, comprising:

motor for driving a compressor;

an inverter for controlling said motor;

a converter responsive to AC for supplying DC of variable voltage to said inverter;

said refrigerator further comprising;

means for driving said motor at a voltage which is lower than said DC voltage at the time of starting of said motor.