Control apparatus of brushless motor and machine and apparatus using brushless motor

• US 6,337,548 B2
• Filed: 02/16/2001
• Issued: 01/08/2002
• Est. Priority Date: 03/23/1998
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Notohara, Yasuo, Tahara, Kazuo, Kawabata, Yukio
• Primary Examiner(s): IP, SHIK LUEN PAUL
• Application Number:
  US09/784,114
• Publication Number:
  US 20010004197A1
• Time in Patent Office: 326 Days
• Field of Search: 318/138, 318/245, 318/254, 318/439, 318/632, 318/701, 318/599, 363/26, 363/134
• US Class Current: 318/400.04
• CPC Class Codes: H02P 6/18 without separate position detecting elements

Abstract

An apparatus such as an air conditioner, refrigerator or washing machine having a control apparatus for use in a brushless motor facing a part of a compressor and/or blower of the apparatus. The control apparatus includes a voltage detector for generating a detection voltage in response to a terminal voltage of plural phases of a stator winding of the brushless motor, a standard voltage generator for generating a standard voltage, a comparator for outputting a comparison result information signal by comparing the detection voltage and said standard voltage, a controller for detecting a rotation position of a rotor of the brushless motor according to the comparison result information signal which is outputted from the comparator and for outputting an electric supply control signal, and an output unit for supplying electric power to the stator winding according to the electric supply control signal.

Claims

1. Apparatus including a control apparatus for use in a brushless motor comprising:

voltage detection means for generating a detection voltage in response to a terminal voltage of plural phases of a stator winding of the brushless motor, standard voltage generation means for generating a standard voltage, comparison means for outputting a comparison result information signal by comparing said detection voltage and said standard voltage, control means for detecting a rotation position of a rotor of the brushless motor according to said comparison result information signal which is outputted from said comparison means and for outputting an electric supply control signal, and output means for supplying electric power to said stator winding according to said electric supply control signal,

wherein said control means detects a position of said rotor according to a pattern of plural phase comparison result information signals,

wherein the brushless motor forms a part of at least one of a compressor and a blower of the apparatus which is one of (a) an air conditioner, (b) a refrigerator and (c) a washing machine, and

wherein said control means controls so as to at least one of (a) extract an “

on”

period or an “

off”

period of a PWM (pulse width modulation) signal according to said comparison results information signal, (b) detect a position of said rotor according to a pattern of plural phase comparison result information signals, (c) determine a pattern of electric supply to said stator winding according to a pattern of plural phase comparison result information signals, (d) detect a period in which a return current flows after an electric supply change-over according to a pattern of said comparison result information signal, (e) detect a rotor position according to a pattern of said comparison result information signal and changes over an electric supply phase according to electric supply information which is stored in a memory, (f) detect a rotor position according to a pattern of said comparison result information signal and changes over an electric supply phase according to a phase control command from an outside source, and (g) carry out a phase control in an operation efficiency importance in a PWM control area and carries out control for proceeding an electric phase in a high rotation importance control area.

2. Apparatus according to claim 1, wherein said control means is constituted by one of a microprocessor having plural input and output ports and a hybrid IC having plural input and output ports.

3. Apparatus according to claim 1, wherein said control means outputs said electric supply control signal which is for said stator winding in response to said rotation position.

4. Apparatus according to claim 1, wherein said control means uses one of an A/D (analog/digital) conversion terminal, a communication use terminal and an input port as a terminal for inputting said phase control command from said outside source.

5. Apparatus according to claim 2, wherein said control means outputs said electric supply control signal which is for said stator winding in response to said rotation position.

6. Apparatus including a control apparatus for use in a brushless motor comprising:

voltage detection means for generating a detection voltage in response to a terminal voltage of plural phases of a stator winding of the brushless motor, standard voltage generation means for generating a standard voltage, comparison means for outputting a comparison result information signal by comparing said detection voltage and said standard voltage, control means for detecting a rotation position of a rotor of the brushless motor according to said comparison result information signal which is outputted from said comparison means and for outputting an electric supply control signal, and output means for supplying electric power to said stator winding according to said electric supply control signal,

wherein said control means detects a position of said rotor according to a pattern of plural phase comparison result information signals, selection holding means for selecting whether said comparison result information signal from said comparison means is to be output from a phase signal or whether a previous level of said comparison result information signal is to be output as a phase signal,

wherein said selection holding means selects holding so as to at least one of operate to output, (a) when a PWM (pulse width modulation) signal is in an “

on”

condition, said comparison information signal from said comparison means as said phase signal as it is, and, (b) when said PWM signal changes to an “

off”

condition, continues to output the level of the condition comparison result information signal which occurred immediately before the “

off”

condition as said phase signal, and

wherein the brushless motor forms a part of at least one of a compressor and a blower of the apparatus which is one of (a) an air conditioner, (b) a refrigerator and (c) a washing machine.

7. Apparatus according to claim 6, wherein said control means is constituted by one of a microprocessor having plural input and output ports and a hybrid IC having plural input and output ports.

8. Apparatus according to claim 6, wherein said control means outputs said electric supply control signal which is for said stator winding in response to said rotation position.

9. Apparatus according to claim 6, further comprising a rectifying circuit for converting an alternating current power source voltage to a direct current voltage, an inverter circuit for converting said direct current voltage to an alternating current voltage and for supplying said alternating current voltage to said brushless motor, and a control circuit for controlling said inverter circuit.

10. Apparatus according to claim 6, further comprising a converter circuit having a rectifying circuit for converting an alternating current power source voltage to a direct current voltage and a chopper circuit for controlling the level of said direct current voltage, an inverter circuit for converting said direct current voltage which is received from said inverter circuit to an alternating current voltage and for supplying said alternating current voltage to said brushless motor, a converter control circuit for controlling a switching operation of said inverter circuit, an inverter control circuit for driving said brushless motor by controlling a switching operation of said inverter circuit, and a control circuit for controlling said converter control circuit and said inverter control circuit.

11. Apparatus including a control apparatus for use in a brushless motor comprising:

voltage detection means for generating a detection voltage in response to a terminal voltage of plural phases of a stator winding of the brushless motor, standard voltage generation means for generating a standard voltage, comparison means for outputting a comparison result information signal by comparing said detection voltage and said standard voltage, control means for detecting a rotation position of a rotor of the brushless motor according to a pattern of a phase signal by obtaining said phase signal according to said comparison result information signal which is outputted from said comparison means and for outputting an electric supply control signal, and output means for supplying electric power to said stator winding according to said electric supply control signal,

wherein after a return current after an electric supply change-over vanishes, a processing is carried out for renewing a phase signal pattern which is correlated to carry out a position detection, and

wherein the brushless motor forms a part of at least one of a compressor and a blower of the apparatus which is one of (a) an air conditioner, (b) a refrigerator and (c) a washing machine.

12. Apparatus according to claim 11, wherein said control means is constituted by one of a microprocessor having plural input and output ports and a hybrid IC having plural input and output ports.

13. Apparatus according to claim 11, wherein said control means outputs said electric supply control signal which is for said stator winding in response to said rotation position.

14. In a brushless motor system having a brushless motor and a control apparatus for controlling the brushless motor, said control apparatus detects a rotor position of said brushless motor in response to the voltage of a stator winding of said brushless motor, wherein said control apparatus controls so as to at least one of (a) extract an “

on”

period or an “

off”

period of a PWM (pulse width modulation) signal only in accordance with a comparison result of a comparison between a terminal voltage of the stator winding and a standard voltage, and (b) detect the position of the rotor of said brushless motor in accordance with the extracted “

on”

period of the PWM signal or the extracted “

off”

period of the PWM signal.