JP2010063303A - Motor drive unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor drive unit which interrupts power supply to a specific control system in response to an instruction from a microcomputer. <P>SOLUTION: A motor drive circuit 65 is supplied with power from a motor power supply Vpp and a control power supply Va. The motor power supply Vpp is connected to an inverter circuit 65a, and the control power supply Va is connected to a motor driving IC. An interrupting circuit 66 receives an on/off instruction signal different from a duty ratio control signal from the microcomputer 61 to interrupt power supply from the control power supply Va to the motor driving IC. As a result, power consumption by the motor driving IC is prevented in the standby mode. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a motor drive device that controls power supply to a motor.

  2. Description of the Related Art Conventionally, as a drive circuit for driving a device such as a motor, a method of providing a switch operation mechanism in a power supply circuit and cutting off power supply to the device (for example, see Patent Document 1) is well known. In the drive circuit described in Patent Document 1, when power supply from the power supply circuit is interrupted, power supply to the drive system and the control system is interrupted, so that standby power consumption may be considered to be almost zero. However, due to the multi-functionalization of devices in recent years, it is necessary to memorize the state before the power supply is cut off in order to execute various controls, so it is not possible to cut off the power supply to the entire control system. It is possible.

For example, in a motor drive device during standby, if power is supplied to a microcomputer but power supply to other control systems is not required, the power supply to a control system that does not need power supply can be shut off. , Power consumption during standby can be reduced.
JP 63-211006 A

  The subject of this invention is providing the motor drive device which can interrupt | block the power supply to a specific control system by the instruction | command of a microcomputer.

  A motor drive device according to a first aspect of the present invention is a motor drive device that performs start, stop, and rotation speed control of a motor based on a rotation speed command signal for rotating and stopping the motor. I have. The microcomputer sends a rotation speed command signal. The cutoff circuit receives a command signal different from the rotation speed command signal from the microcomputer and cuts off the power supply to the motor.

  In this motor drive device, when the motor is in a standby state, the power supply to the motor can be cut off by the cutoff circuit, so that power consumption in the standby state is reduced.

  A motor drive device according to a second invention is the motor drive device according to the first invention, further comprising a motor drive circuit for inputting a drive voltage to the motor. The motor drive circuit is supplied with a motor power source that is a source of drive voltage and a control power source that turns on the motor drive circuit. The cutoff circuit cuts off the supply of control power.

  In this motor drive device, since the control power supply is generally lower than the motor power supply, the ratings of the components constituting the cutoff circuit are small. As a result, a low-rated semiconductor element can be used, and an increase in component costs is suppressed. Also, cutting off the low voltage circuit is more reliable and lowers noise.

  A motor drive device according to a third invention is the motor drive device according to the second invention, wherein a regulator is connected between the motor drive circuit and the shut-off circuit. In this motor drive device, power consumption in the regulator is suppressed.

  A motor drive device according to a fourth aspect of the present invention is the motor drive device according to any one of the first to third aspects, wherein the cutoff circuit is a semiconductor element. In this motor drive device, the durability of the cutoff circuit is improved and the reliability is increased.

  A motor drive device according to a fifth aspect of the present invention is the motor drive device according to the fourth aspect of the present invention, wherein the cutoff circuit and the microcomputer signal are insulated by a photocoupler. In this motor drive device, since the so-called primary side (breaking circuit side) and secondary side (microcomputer signal side) are insulated, safety is improved and noise resistance is also improved.

  In the motor drive device according to the first aspect of the present invention, when the motor is in the standby state, the power supply to the motor can be interrupted by the cutoff circuit, so that power consumption in the standby state is reduced.

  In the motor drive device according to the second aspect of the present invention, it is possible to use a low-rated semiconductor element, thereby suppressing an increase in component costs. Also, cutting off the low voltage circuit is more reliable and lowers noise.

  In the motor drive device according to the third aspect of the invention, power consumption in the regulator is suppressed.

  In the motor drive device according to the fourth aspect of the invention, the durability of the cutoff circuit is improved and the reliability is increased.

  In the motor drive device according to the fifth aspect of the invention, the so-called primary side (breaking circuit side) and secondary side (microcomputer signal side) are insulated, so that safety is improved and noise resistance is also improved.

  Embodiments of the present invention will be described below with reference to the drawings. The following embodiments are specific examples of the present invention and do not limit the technical scope of the present invention.

<Air conditioner>
FIG. 1 is a perspective view of an air conditioner including a motor driving device according to an embodiment of the present invention. In FIG. 1, in the air conditioner 1, an air cleaning unit 2, a dehumidifying unit 3, a humidifying unit 4, a blower 5 and a control unit 6 are housed in a main body 10. In the present embodiment, a handle 7 is provided at the upper part of the side surface of the main body 10 so that the user can easily move the air conditioner 1, and the lower surface of the main body 10 (the surface facing the indoor floor surface). A caster 8 is provided.

  The blower 5 is located on the side opposite to the air cleaning unit 2 with respect to the main body 10, and when viewed from the air cleaning unit 2 side, the air cleaning unit 2, the dehumidifying unit 3, the humidifying unit 4, and the blower 5 in this order. Are lined up. When the blower 5 is operating, air is sucked in from the air cleaning unit 2 side, and after passing through the dehumidifying unit 3, an air air path A that passes through the humidifying unit 4 and reaches the blower 5 is formed.

  FIG. 2 is a perspective view of the upper part of the main body of the air conditioner. In FIG. 2, an air outlet 11 is provided in the upper portion of the main body 10, and air that has been purified and conditioned through the air flow path A is blown out from the air outlet 11. The air blowing direction can be changed by the louver 12 installed at the opening of the air outlet 11.

  The louver 12 includes a partition blade 120, a first wind direction adjusting blade 121, and a second wind direction adjusting blade 122. The first wind direction adjusting blade 121 and the second wind direction adjusting blade 122 intersect with the partition blade 120 and are supported by the partition blade 120 so as to be tiltable with respect to the vertical direction. The louver 12 is driven by a stepping motor 19. In FIG. 1, the louver 12 is in a closed state, but when the operation is started, it is automatically opened directly above by the stepping motor 19.

  Further, an operation panel 60 (see FIG. 1) is provided on the upper portion of the main body 10 and is protected by the cover 13. The control unit 6 (see FIG. 1) is located below the operation panel 60, and based on a signal input from the operation panel 60, the air cleaning unit 2, the dehumidifying unit 3, the humidifying unit 4, the blower 5, and the louver. 12 is controlled. The operation mode is switched by an operation switching button on the operation panel 60.

<Operation panel 60>
FIG. 3 is a perspective view of the operation panel. In FIG. 3, on the operation panel 60, an operation on / off button 601, an operation switching button 602, an air volume selection button 603, a humidity selection button 604, a course selection button 605, a timer selection button 606, an auto louver button 607, and a recommendation Buttons 608 are provided, and by pressing each button, a signal corresponding to the pressed button is input to the control unit 6 disposed below the operation panel 60. The control unit 6 includes a microcomputer and a memory.

  For example, the operation on / off button 601 is a button for turning on / off the power supply to the air conditioner 1. After the power plug is inserted into an outlet, the operation is started when pressed, and the operation is performed when pressed again. Stop. The operation switching button 602 is a button for selecting an operation mode, and can select any one of “air cleaning”, “humidification”, and “dehumidification”.

<Motor drive device>
FIG. 4 is a circuit diagram of the motor drive device. In FIG. 4, the motor 50 is a brushless DC motor that rotates the blower 5, and includes a stator having a built-in drive coil and a rotor having a magnet facing the stator. Three Hall elements 500 are incorporated on the stator side of the motor 50, and the rotational speed of the rotor of the motor 50 can be detected via the Hall elements 500.

  The control unit 6 includes a microcomputer 61, a power supply circuit 62, and a motor drive circuit 65 in order to control the rotation speed of the motor 50. The microcomputer 61 includes a CPU and a memory, and controls the power supply circuit 62 and the motor drive circuit 65 so that the motor 50 has a predetermined rotation speed while monitoring the detection signals of the three Hall elements 500.

  The power supply circuit 62 includes a bridge circuit 62a made of a diode and an electrolytic capacitor 62b, and generates a DC motor power supply Vpp and a control power supply Va from the AC power supply 100. The motor power supply Vpp is a source of driving voltage for the motor 50. The control power source Va is a power source for turning on the motor drive circuit 65. In the power supply circuit 62, the second DC power supply Vb and the third DC power supply Vc are generated through the transformer 62c.

  The motor drive circuit 65 includes an inverter circuit 65a and a motor drive IC 65b. Inverter circuit 65a is a bridge circuit composed of six transistors, and is supplied with motor power Vpp. The motor drive IC 65b is an IC that inputs a drive signal to each transistor of the inverter circuit 65a, and is supplied with a control power supply Va.

  A regulator 64 is connected between the control power supply Va and the motor drive IC 65b, and the voltage of the control power supply Va is converted into a voltage suitable for the motor drive IC 65b by the regulator 64. In addition, a cutoff circuit 66 is connected between the control power supply Va and the regulator 64.

  The cutoff circuit 66 is a circuit that opens and closes an electrical connection between the control power supply Va and the regulator 64, and includes a transistor 66a and a photocoupler 66b. The transistor 66 a is connected between the control power supply Va and the regulator 64. The photocoupler 66b is connected to the base of the transistor 66a.

  The photocoupler 66b includes a phototransistor 661 and a light emitting diode 662, and actually the phototransistor 661 is connected to the base of the transistor 66a. The light emitting diode 662 is connected between the second control power supply Vb and the microcomputer 61.

  For example, when the microcomputer 61 turns on the signal line of the light emitting diode 662, the light emitting diode 662 emits light, the phototransistor 661 is turned on, and the transistor 66a is also turned on. The voltage is input to the motor drive IC 65b.

  Conversely, when the microcomputer 61 turns off the signal line of the light emitting diode 662, the light emitting diode 662 does not emit light, so that the phototransistor 661 does not conduct and the transistor 66a does not conduct. As a result, the control power Va is not supplied to the regulator 64 and no voltage is input to the motor drive IC 65b.

  In this embodiment, the photocoupler 66b is used in the cutoff circuit 66 to cause the transistor 66a to perform a switching operation. However, the present invention is not limited to this, and a signal is directly input from the microcomputer 61 to the base of the transistor 66a. Then, the switch operation may be performed.

  In the motor drive device according to the present embodiment, the microcomputer 61 can change the rotation speed of the motor 50 by a pulse width modulation (PWM) method. The PWM method is a method in which the rotation speed is changed by changing the ratio (hereinafter referred to as the duty ratio) between the ON time and the OFF time of the drive voltage input to the motor 50. The microcomputer 61 inputs a control signal for controlling the duty ratio (hereinafter referred to as a duty ratio control signal) to the motor drive IC 65b.

  The duty ratio control signal of the microcomputer 61 is input to the motor drive IC 65 b via the second photocoupler 67. The second photocoupler 67 includes a phototransistor 671 and a light emitting diode 672. The phototransistor 671 is connected between the motor drive IC 65 b and the ground, and the light emitting diode 672 is connected between the second control power supply Vb and the microcomputer 61.

  For example, when the microcomputer 61 turns on the signal line of the light emitting diode 672, the light emitting diode 672 emits light and the phototransistor 671 becomes conductive. While the phototransistor 671 is conducting, a control signal is input to the motor drive IC 65b.

  Conversely, when the microcomputer 61 turns off the signal line of the light-emitting diode 672, the light-emitting diode 672 does not emit light, and thus the phototransistor 671 does not conduct. While the phototransistor 671 is not conducting, the transistor 66a is not conducting. As a result, the control power supply Va is not supplied to the regulator 64, and no control signal is input to the motor drive IC 65b. In this way, the duty ratio is controlled by the microcomputer 61.

  Note that the microcomputer 61 causes the microcomputer 61 itself to input a signal input from the motor drive IC 65b to the inverter circuit 65a as a feedback signal in order to monitor whether or not the duty ratio is a target value.

  The feedback signal is input to the microcomputer 61 via the third photocoupler 68. The third photocoupler 68 includes a phototransistor 681 and a light emitting diode 682. The phototransistor 681 is connected between the microcomputer 61 and the ground, and the light emitting diode 682 is connected in the middle of a signal line that exits from the motor drive IC 65b and returns to the motor drive IC 65b.

  For example, since the same signal as the drive signal input to the inverter circuit 65a is input to the light emitting diode 682, the light emitting diode 682 emits light for a time corresponding to the ON time of the drive signal, and the phototransistor 681 is driven. Conduction is performed for a time corresponding to the ON time of the signal. As a result, the feedback signal is input to the microcomputer 61 for a time corresponding to the ON time of the drive signal.

<Operation of air conditioner>
In FIG. 3, as long as the power plug is inserted into the outlet, the air conditioner 1 starts operation when the operation on / off button 601 is pressed, and stops operation when pressed again. Since the control unit 6 stores the operation mode before the stop as the operation mode, when the operation is resumed, the operation mode before the stop is executed until a new operation mode is selected by the operation switching button 602. Since the air conditioner 1 needs to operate the blower 5 in any of the “air cleaning”, “humidification” and “dehumidification” operation modes, the control unit 6 is connected via the motor drive circuit 65. The rotation of the motor 50 is controlled.

<Reduce power consumption during standby>
Since the motor drive circuit 65 is supplied with the motor power Vpp and the control power Va, the power is consumed even when the operation is stopped unless the power plug is removed from the outlet. In the present embodiment, when the operation is stopped with the power plug inserted into the outlet, the power supply to the motor driving IC 65b is cut off in order to suppress so-called standby power consumption.

  When the operation on / off button 601 is pressed from the operation state, the control unit 6 sends a duty ratio control signal for setting the duty ratio to 0 via the photocoupler 67 to the motor drive IC 65b and stops the motor 50. . Thereafter, the microcomputer 61 turns off the signal line of the light emitting diode 662 of the cutoff circuit 66. Since the light emitting diode 662 does not emit light, the phototransistor 661 does not conduct and the transistor 66a does not conduct. As a result, since the control power supply Va is not supplied to the regulator 64 and no voltage is input to the motor drive IC 65b, power consumption in the regulator 64 and the motor drive IC 65b is prevented.

  A method of preventing power consumption by interrupting the supply of the motor power supply Vpp is also conceivable. However, since the motor power supply Vpp is generally larger than the control power supply Va, a transistor 66a used for the cutoff circuit 66 for cutting off the supply of the control power supply Va is used as the cutoff circuit for cutting off the supply of the motor power supply Vpp. It should be noted that a transistor and a photocoupler having a larger capacity than that of the photocoupler 66b are used.

<Features>
The motor drive circuit 65 is supplied with a motor power Vpp and a control power Va. The motor power supply Vpp is connected to the inverter circuit 65a, and the control power supply Va is connected to the motor drive IC. The cutoff circuit 66 receives an on / off command signal different from the duty ratio control signal from the microcomputer 61 and cuts off the supply of the control power supply Va to the motor drive IC. As a result, power consumption in the motor drive IC is prevented during standby.

  As described above, according to the present invention, the power consumption of the motor drive circuit during standby can be suppressed, so the outdoor unit of the air conditioner and the fan motor of the indoor unit, or the fan motor of the outdoor unit of the heat pump water heater Useful for.

The perspective view of the air conditioner provided with the motor drive device concerning one embodiment of the present invention. The perspective view of the main body upper part of an air conditioner. The perspective view of an operation panel. The circuit diagram of a motor drive device.

Explanation of symbols

50 Motor 61 Microcomputer 64 Regulator 65 Motor drive circuit 66 Cutoff circuit

Claims (5)

A motor driving device for starting, stopping and controlling the rotational speed of the motor (50) based on a rotational speed command signal for rotating and stopping the motor (50),
A microcomputer (61) for sending the rotational speed command signal;
A cutoff circuit (66) for receiving a command signal different from the rotational speed command signal from the microcomputer (61) and shutting off the power supply to the motor (50);
Motor drive device. A motor drive circuit (65) for inputting a drive voltage to the motor (50);
The motor drive circuit (65) is supplied with a motor power supply (Vpp) that is a source of the drive voltage and a control power supply (Va) that turns on the motor drive circuit (65).
The cutoff circuit (66) shuts off the supply of the control power supply (Va).
The motor drive device according to claim 1. A regulator (64) is connected between the motor drive circuit (65) and the shut-off circuit (66);
The motor drive device according to claim 2. The blocking circuit (66) is a semiconductor element;
The motor drive device of any one of Claims 1-3. The interruption circuit (66) and the signal of the microcomputer (61) are insulated by a photocoupler (66b).
The motor drive device according to claim 4.

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