JP5865327B2 - Motor drive control device, air conditioner, ventilation fan and heat pump type water heater - Google Patents

Description

  The present invention relates to a motor drive control device that drives a motor that rotates a fan, and to an air conditioner, a ventilation fan, and a heat pump type water heater equipped with the motor drive control device.

  In a conventional air conditioner, a motor and a drive circuit using a switching device such as a relay are used to protect the motor and the drive circuit from the electromotive force of the motor that is generated by the rotation of the fan when the fan rotates. Is disclosed (for example, see Patent Document 1).

  In addition, a method is disclosed in which, when an electromotive force is generated in an outdoor unit due to outside wind, the compressor is driven to consume the electromotive force and prevent the drive circuit from being destroyed (see, for example, Patent Document 2).

  Furthermore, a method is disclosed in which when the detected current value exceeds the protection level, the switching element is returned to the off state to stop the start-up, and the motor and the drive circuit are protected (see, for example, Patent Document 3).

  In addition, a method for reducing the capacity of an electrolytic capacitor output from a rectifier circuit in a drive circuit to reduce cost and weight of the drive circuit is disclosed (for example, see Patent Document 4).

JP-A-63-103621 JP 2001-263767 A JP 2005-124330 A Japanese Patent Laid-Open No. 2005-20986

  In the conventional technology, the fan and the drive circuit are rotated by outside wind, and the motor and the drive circuit are connected by using a switching device such as a relay in order to protect the motor and the drive circuit from the electromotive force of the motor generated by the rotation of the fan. Since it is disconnected, the addition of switching means will increase the cost of the circuit, and in the event of a power failure, the power supply to the switching means will cause intermittent contact switching, making it difficult to ensure contact life There was a problem. Further, in the problem of contact life, it may be possible to use a semiconductor. However, since a withstand voltage is required, there is a problem that a circuit added for protection also increases the cost.

  Further, in the conventional technology that drives the compressor and suppresses the regenerative voltage due to the electromotive force, there is a problem that the regenerative voltage cannot be suppressed when outside wind occurs at the timing when the drive system of the compressor enters the protection operation. there were.

  In addition, when the technology for reducing the capacity of the electrolytic capacitor of the output of the rectifier circuit, which has been actively developed in recent years, is applied to the drive circuit, the rate of increase of the DC voltage due to regeneration increases, and the compressor There is a problem that it becomes difficult to prevent the breakdown of the breakdown voltage of the drive circuit.

  Further, when protection is performed by turning off all the switching elements, the withstand voltage of the switching elements of the drive circuit is required, resulting in an increase in cost. Conversely, if the breakdown voltage of the switching element is to be lowered, it is necessary to lower the electromotive force of the motor. In this case, the motor current during normal operation increases, and the circuit and motor loss during steady operation increase. In recent years, from the viewpoint of global warming countermeasures, the reduction of losses required for air conditioners has become a major issue.

  Further, when the electromotive force of the motor is reduced, the number of turns of the motor winding is limited, the winding inductance value becomes small, and when driven by an inverter, the time change di / dt of the winding current becomes large. There has been a problem that motor noise and electromagnetic noise increase due to this rapid current change.

  Further, when the induced voltage of the motor generated by the rotation of the motor by the external wind exceeds the withstand voltage of the drive circuit, large components such as power elements and electrolytic capacitors are destroyed. As a result, there has been a problem that the user may feel uncomfortable that the repair cost of the drive circuit is generated or the air conditioner cannot be used until the parts replacement and repair are completed.

  The present invention has been made to solve the above-described problems, and can protect a motor drive control device from an electromotive force of a motor generated by rotation of the fan due to rotation of the fan by outside wind. Thus, a motor drive control device capable of increasing the number of turns of the motor winding and reducing the motor current is obtained.

A motor drive control device according to the present invention is a motor drive control device that rotates a fan and drives a motor in which one end of each phase of a winding is connected, and converts the DC voltage into an AC voltage to convert the motor An inverter circuit that is applied to the inverter circuit, a control unit that controls the operation of the motor by controlling the inverter circuit, and a bus voltage detection unit that detects a voltage of a power supply line that supplies power to the inverter circuit. Generates an electromotive force in which the line voltage is equal to or higher than the withstand voltage of the inverter circuit under an outdoor wind condition in which the rotation speed of the motor is higher than the rotation speed in the actual operation range, and the inverter circuit A switching element at one end of each phase of the wire, and when the bus voltage detection means detects that the voltage of the power supply line due to the electromotive force of the motor is equal to or higher than a certain voltage, the control Stage, the controls the switch patterns of the switching elements, the phases of one end of the winding of the motor is to short-circuit via the switching element.

  Since the present invention can protect the motor drive control device from the electromotive force of the motor generated by the rotation of the fan due to the rotation of the fan, the number of turns of the motor winding can be increased, The motor current can be reduced.

It is a schematic block diagram of the air conditioner which concerns on Embodiment 1 of this invention. It is a schematic block diagram of the outdoor unit of the air conditioner which concerns on Embodiment 1 of this invention. 1 is a circuit diagram of a motor drive control device according to Embodiment 1 of the present invention. It is the figure which showed the relationship between the outdoor fan rotation speed and motor line voltage which concern on Embodiment 1 of this invention. It is a circuit diagram of the motor drive control apparatus which concerns on Embodiment 2 of this invention. It is a circuit diagram of the motor drive control apparatus which concerns on Embodiment 4 of this invention. It is a circuit diagram of the motor drive control apparatus which concerns on Embodiment 5 of this invention. It is a circuit diagram of the motor drive control apparatus which concerns on Embodiment 5 of this invention. It is a circuit diagram of the motor drive control apparatus which concerns on Embodiment 5 of this invention. It is the schematic block diagram which showed typically the cross section of the ventilation fan which concerns on Embodiment 9 of this invention. It is a schematic block diagram of the heat pump type water heater which concerns on Embodiment 10 of this invention. It is a figure which shows the BH characteristic of the permanent magnet from which a coercive force falls with respect to a temperature rise. It is a figure which shows the temperature rise inside a motor at the time of a short circuit brake. It is a figure which shows the BH characteristic of the permanent magnet which a coercive force raises with respect to a temperature rise. It is a motor structure figure using a permanent magnet in a stator.

Embodiment 1 FIG.
FIG. 1 is a schematic configuration diagram of an air conditioner according to Embodiment 1 of the present invention. 1, the air conditioner according to Embodiment 1 includes a compressor 103, a four-way valve 104, an outdoor heat exchanger 105, an expansion valve 106, an indoor heat exchanger 107, an outdoor fan 108, and an indoor fan that constitute a refrigeration cycle. 109. Further, the air conditioner is connected to the commercial power source 1, and includes a compressor inverter 102 that drives the motor of the compressor 103, a motor drive control device 110 that drives a motor 7 (described later) that rotates the outdoor fan 108, and an indoor fan 109. Speed control circuit 112, air conditioner control unit 113 that controls the entire air conditioner, light receiving unit 114 of an infrared remote controller, abnormality display unit 115 that informs the user of an abnormality of the device, infrared for the user to operate The remote control 116 is used.

  FIG. 2 is a schematic configuration diagram of the outdoor unit of the air-conditioning apparatus according to Embodiment 1 of the present invention. In FIG. 2, the outdoor heat exchanger 105 is arrange | positioned at the left side part and back part of the outdoor unit 117, and the compressor 103 is arrange | positioned at the right side part. An outdoor fan 108 is provided inside the outdoor heat exchanger 105. The outdoor fan 108 is constituted by a propeller fan 108F and a motor 7 (described later) driven by a motor drive control device 110. By rotating the propeller fan 108F, the outdoor fan 108F is viewed from the directions of arrows A and B shown in FIG. The outdoor heat exchanger 105 is configured to promote heat exchange by sucking outside air and discharging it in the direction of arrow C.

That is, during normal operation, the motor drive control device 110 rotates the propeller fan 108F in the rotation direction (forward direction) that generates wind from the A and B arrow directions shown in FIG. Cool down. That is, motor torque is generated so that the motor 7 rotates in the positive direction.
The outdoor unit 117 is installed outdoors.

  FIG. 3 is a circuit diagram of the motor drive control apparatus according to Embodiment 1 of the present invention. In FIG. 3, the motor drive control device 110 includes a rectifier circuit 2, an inverter circuit 5 that converts a DC voltage into an AC voltage and applies it to the motor, and a control unit that controls the operation of the motor 7 by controlling the inverter circuit 5. A three-phase synchronous motor (hereinafter referred to as “motor”), which is composed of sensorless control and braking control means 10, current detection means 11, and bus voltage detection means 13, which are driven by electric power supplied from the commercial power source 1. It controls the operation of 7).

  As for the commercial power source 1, 100 V 50 Hz or 60 Hz single-phase alternating current is generally used in a general Japanese home. In some homes, businesses, and overseas, single-phase / three-phase alternating current of 200V or more may be used.

  The rectifier circuit 2 is a full-wave rectifier circuit, and converts the AC voltage of the commercial power supply 1 into a DC voltage. In the first embodiment, a single-phase 200 V full-wave rectifier circuit will be described. When the commercial power source 1 is AC200V, it is converted to DC280-250V. The rectifier circuit 2 is configured by bridge-connecting rectifier diodes 3a to 3d of four semiconductor switch elements. Furthermore, it is smoothed by the electrolytic capacitor 4. The electrolytic capacitor 4 is not limited to an electrolytic capacitor, and may be another capacitor.

  The inverter circuit 5 receives the DC voltage output rectified by the rectifier circuit 2 and performs PWM control by the operation of sensorless control means and braking control means 10 described later. Convert to phase alternating current. The inverter circuit 5 is configured by bridge-connecting switching elements 6a to 6f made of a semiconductor such as a transistor, for example. In the first embodiment, a MOSFET is used as the switching element 6. Each switching element 6a to 6f includes a high-speed diode in parallel in the reverse current direction. The built-in high-speed diode functions to flow a reflux current when the switching elements 6a to 6f are turned off. Furthermore, the inverter circuit 5 is provided with a shunt resistor 12 that converts the current of each arm of the switching element 6 into a voltage. The bus voltage detection means 13 has a control power supply, obtains a low voltage constant voltage from the high voltage bus voltage, detects the inverter bus voltage, and outputs it to the sensorless control means and the brake control means 10.

The motor 7 is a six-slot four-pole three-phase synchronous motor (brushless DC motor: BLDCM), and drives the propeller fan 108F of the outdoor unit 117. This motor 7 has a three-phase winding 8, a stator (not shown) having a three-phase winding in which one terminal of each winding 8 serves as a common terminal, and a magnet. Of the rotor 9. Each terminal of the motor 7 is connected to the output terminal of the inverter circuit 5. Further, when the air conditioner (installed product) on which the motor 7 is mounted is at the maximum outside wind condition, for example, when the outside wind is 30 m / s, the line voltage (described later) exceeds the withstand voltage of the motor drive control device 110. For example, a motor 7 that generates an electromotive force of 350 V or more is used.
The rotor 9 corresponds to the rotor in the present invention, the magnet corresponds to the permanent magnet in the present invention, and the stator corresponds to the stator in the present invention.

  The current detection means 11 amplifies and level-shifts the current of each arm of the inverter circuit 5 converted into a voltage by the shunt resistors 12a, 12b, and 12c of the inverter circuit 5, and supplies each arm current to the sensorless control means and the brake control means 10. Is output.

The sensorless control means and the braking control means 10 perform PWM (Pulse Width Modulation) by determining the switching time of the switching element 6 of the inverter circuit 5 from each arm current obtained from the current detection means 11, By applying a voltage to each winding 8 of the motor 7 and controlling the winding current of the winding 8, a rotating magnetic field synchronized with the rotor 9 is generated, and the motor 7 is driven and controlled. Further, the sensorless control means and the braking control means 10 control the inverter circuit 5 by an operation to be described later, flow a short-circuit current through the winding 8 of the motor 7 to suppress the rise of the bus voltage, and perform electric braking (short-circuiting). Apply the brake.
In such a configuration, the propeller fan 108F of the outdoor unit 117 is rotated by the external wind, and the electromotive force of the motor 7 generated by the rotation of the propeller fan 108F will be described with reference to FIG.

  FIG. 4 is a diagram showing the relationship between the outdoor fan rotation speed and the motor line voltage according to Embodiment 1 of the present invention. In FIG. 4, the vertical axis represents the line voltage (bus voltage) generated by the electromotive force of the motor 7, and the horizontal axis represents the rotation speed of the propeller fan 108 </ b> F of the outdoor unit 117. As shown in FIG. 3, when all the switching elements 6a to 6f of the inverter circuit 5 are OFF, for example, when the operation of the motor 7 is stopped, the inverter circuit 5 becomes a three-phase full-wave rectifier circuit. In such a circuit, when the propeller fan 108F of the outdoor unit 117 is rotated by outside wind or the like, the rotor 9 of the motor 7 is rotationally driven to induce an electromotive force. The line voltage of the motor 7 is applied between the terminals of the electrolytic capacitor 4 via the inverter circuit 5, and the line voltage peak value of the motor 7 and the bus voltage at both ends of the electrolytic capacitor 4 become the same.

  As shown in FIG. 4, in the conventional motor, for example, under the maximum outside wind condition of 30 m / s of the fan motor, the rotation speed of the motor is 4000 rpm and the line voltage is 350V. As described above, the conventional motor does not exceed the withstand voltage 350 V of the electrolytic capacitor 4. Therefore, the line voltage generated only 114 V at the maximum rotation speed of 1300 rpm in the actual operation range.

  On the other hand, the motor 7 according to the first embodiment uses a motor 7 that generates an electromotive force in which the line voltage is equal to or higher than the withstand voltage of the electrolytic capacitor 4 under the maximum outside wind condition. By using such a motor 7, as shown by the thick line in FIG. 4, for example, the minimum value of the bus voltage at the maximum rotation speed of 1300 rpm in the actual operation region is 250V. For this reason, when the outside wind is reached, the breakdown voltage of the electrolytic capacitor 4 reaches 350 V at 1820 rpm.

  Therefore, in the first embodiment of the present invention, the sensorless control unit and the braking control unit 10 are configured such that when the bus voltage detected by the bus voltage detection unit 13 exceeds a predetermined value, for example, becomes 350V or 350V. When the predetermined value does not exceed, the switch pattern of the inverter circuit 5 is switched so that the bus voltage is equal to or lower than the withstand voltage of the electrolytic capacitor 4, and a short circuit current is passed through the winding 8 of the motor 7 to increase the bus voltage. Suppress. That is, as the switch pattern of the inverter circuit 5, the switches of the switching elements 6b, 6d, 6f are turned on and the switches of the switching elements 6a, 6c, 6e are turned off, or the switches of the switching elements 6b, 6d, 6f are turned on. And the switches of the switching elements 6a, 6c and 6e are turned on. That is, by outputting a zero vector as a switch pattern, each winding 8 of the motor 7 is short-circuited, and a short-circuit current is passed through the motor 7.

  By such an operation, the lines of the motor 7 are short-circuited, and the line voltage caused by the motor electromotive force generated by the rotation of the external wind is not applied to both ends of the electrolytic capacitor 4, thereby suppressing an increase in the bus voltage. However, the breakdown voltage of the electrolytic capacitor 4 is not exceeded.

Here, the direction of rotation of the propeller fan 108F due to the external wind may be forward or reverse.
When the outside wind is in the direction from the outdoor fan 108 to the outdoor heat exchanger 105 (hereinafter “reverse outside wind”), the motor 7 rotates in the direction opposite to that during normal operation. On the other hand, when the outdoor air from the outdoor heat exchanger 105 is in the direction of the outdoor fan 108 (hereinafter “positive external air”), the motor 7 rotates in the same direction as during normal operation. In the present embodiment, the outdoor unit 117 is not provided with means for preventing inflow of outside wind such as a wind pressure shutter. For this reason, when the outside wind in the reverse direction and the outside wind in the forward direction are blown at the same wind speed, the amount of inflow into the outdoor unit 117 is larger in the reverse direction, and the rotational speed of the motor 7 is The rotational speed in the reverse direction is higher than the rotational speed in the direction.

When the motor 7 rotates in the reverse direction due to the external wind in the reverse direction, a brake torque can be generated in the rotation direction by the short-circuit current, and application of the induced voltage to the motor drive control device 110 can be reduced. Further, when the motor 7 rotates in the positive direction due to the external wind in the positive direction, torque in the reverse direction can be generated, and application of the induced voltage to the motor drive control device 110 can be reduced.
Thus, in the case of a short-circuit brake, since a brake torque can be generated in the reverse direction of the rotational torque due to the external wind with a single switch operation, means for determining the forward and reverse direction of the torque generated by the external wind, etc. Even if not, application of the induced voltage to the motor drive control device 110 can be reduced.

Next, demagnetization of the motor 7 will be described.
The short circuit current resulting from the torque generated by the outside wind increases as the outside wind amount increases. Further, when the outside wind continues to blow continuously, heat is generated due to the torque generated by the inverter circuit 5, and the temperature inside the motor rises.

  In this case, since there is a concern about the demagnetization of the motor 7 due to the short-circuit current of the motor 7 and the increase in the internal temperature of the motor 7 when the outside wind exceeds the maximum outside wind condition, the motor 7 satisfying the following relationship is used.

The short circuit current of the motor 7 follows the following formula.
I = A · K · N / {R ² + (2πfL) ² } ^1/2 (Formula 1)
f = P · N / 60 (Formula 2)
Imax = 60 · A · K / (P · L) (Formula 3)
I: Short-circuit current K: Induced voltage constant L: Winding inductance R: Winding resistance f: Electric frequency of induced voltage of motor A: Proportional constant N: Number of motor rotations P: Number of pole pairs of motor Imax: Maximum value of short-circuit current In Equations 1 and 2, when the number of revolutions N is infinite, the value of the maximum current Imax at the time of short circuit is as shown in Equation 3: electromotive force constant K, motor pole pair number P, winding inductance L. For this reason, the motor 7 that satisfies the relationship that the maximum value Imax of the short-circuit current is equal to or less than the demagnetization current is used. As a result, there is no concern about demagnetization of the motor 7. In the first embodiment, the number of pole pairs is set to 2, but if there is no freedom to change the inductance value or the induced voltage constant due to the winding, it is possible to take measures by setting the number of pole pairs to a large value of 2 or more. It is.

  Thus, since the short circuit current does not exceed the maximum value of the short circuit current even if the rotational speed increases, the motor will not be demagnetized indefinitely and the function as a motor will not be lost.

  As described above, in the first embodiment, when the bus voltage exceeds a predetermined value, the switch pattern of the inverter circuit 5 is switched, and a short-circuit current is supplied to the winding 8 of the motor 7 to suppress an increase in the bus voltage. As a result, breakdown of the motor drive control device 110 caused by the electromotive force of the motor 7 can be prevented without adding an expensive switching means such as a relay. Moreover, since the short circuit brake is applied by switching of the switching element 6 which is a semiconductor element, there is no concern about the contact life.

  In addition, since the circuit breakage of the motor drive control device 110 can be avoided, it is possible to avoid the occurrence of circuit repair costs and the stoppage of the function of the air conditioner for repairs and parts replacement. As a result, the user does not feel uncomfortable.

  Further, since the withstand voltage can be protected only by the operation of the motor drive control device 110, the motor drive control device 110 can be protected even when the compressor inverter 102 is stopped by the protection operation.

  In the first embodiment, as shown in FIG. 4, the line voltage of the motor 7 can be set to 250 V at the maximum rotation speed of 1300 rpm in the actual operation region. For this reason, compared with the conventional motor, the current of the motor at the same output is 117/250, which can be ½ or less. The on-loss of the switching elements 6a to 6f of the inverter circuit 5 is proportional to the square of the current on the FET side and proportional to the current on the diode side. Also, the switching loss has a characteristic that depends on the current. Furthermore, since the loss in the shunt resistor 12 is also proportional to the square of the current, when the same inverter circuit 5 is used with the same output, the first embodiment can greatly reduce the inverter loss as compared with the conventional motor. It becomes possible.

  Further, the heat dissipation condition of the switching element 6 is eased by reducing the inverter loss, and when the heat dissipating fin and the overheat protection circuit are necessary in the prior art, there is an effect of reducing the cost by reducing the heat dissipating fin and the overheat protection circuit. .

  In the first embodiment, the same rotor or stator is used, the number of turns of the winding 8 is increased, and the electromotive force of the motor 7 can be increased. Since the inductance of the winding 8 is proportional to the square of the number of turns of the winding 8, it is four times when calculated from the line voltage ratio. Therefore, when driven by the inverter circuit 5, the time change di / dt of the winding current can be reduced by ¼. Therefore, the effect of reducing the noise of the motor 7 generated by the current change can also be obtained. This effect is effective in a fan motor that cannot be soundproofed due to wind path pressure loss. Further, the reduction of di / dt has an effect of reducing the generation of electromagnetic noise. Furthermore, the reduction of di / dt has the effect of reducing the current ripple when driving the inverter and reducing the high-frequency iron loss of the motor 7.

  Further, in the conventional technology, when the motor is opened by the opening / closing means during the outside wind, the motor terminal voltage reaches 769 V under the maximum outside wind condition of 30 m / s, and the opening / closing means, the connection between the motor and the opening / closing means, and the connector The withstand voltage is required and is extremely expensive, but this can be avoided in the first embodiment.

  Further, in the air conditioner, since the propeller fan 108F of the outdoor unit 117 is made of plastic, when the rotational speed increases due to the external wind and exceeds the limit rotational speed, it is destroyed by centrifugal force. Since this limit point is also in the vicinity of the maximum outside wind condition, even if the drive circuit can be protected by opening the motor or stopping the inverter as in the prior art, it is a problem to ensure the blade breaking resistance. In the first embodiment, when the bus voltage exceeding the withstand voltage is generated, that is, when the rotational speed of the motor 7 exceeds a predetermined value, the short-circuit brake is continuously applied, so that the propeller fan 108F reaches the same outside wind speed. Since the number of revolutions can be reduced as compared with motor open trains and inverter stops that do not generate forward / reverse bidirectional braking torque, when the same propeller fan 108F is used, there is also an effect that the outside wind resistance leading to destruction increases.

  In the first embodiment, the short-circuit brake is operated only by turning each switching element 6 of the inverter circuit 5 ON / OFF. However, the same effect can be obtained by switching intermittently or switching using PWM. Needless to say.

In the first embodiment, the motor 7 that satisfies the relationship in which the maximum value Imax of the short-circuit current is equal to or less than the demagnetization current is used. However, using such a motor is not possible due to motor design constraints. In this case, there is a method for increasing the demagnetization resistance of the permanent magnet included in the rotor 9.
Usually, the demagnetization characteristic of the motor 7 greatly depends on the magnet temperature. Hereinafter, a description will be given separately for a permanent magnet whose coercive force decreases with increasing temperature and a permanent magnet whose coercive force increases with increasing temperature.

FIG. 12 is a diagram showing the BH characteristics of a permanent magnet whose coercive force decreases with increasing temperature. FIG. 12 shows the BH characteristics of a permanent magnet whose coercive force decreases with increasing temperature of a rare earth magnet containing, for example, neodymium or samarium.
As shown in FIG. 12, for example, the coercive force at 20 ° C. at room temperature is about 1100 kA / m, whereas the coercive force at 100 ° C. is about 370 kA / m. Will drop to 3. However, in general, rare earth magnets containing neodymium, samarium, etc. have high magnetic flux density per volume, which can reduce the amount of magnetic field generated by the winding current for the same output, and reduce copper loss due to winding resistance and low loss. A highly efficient motor can be obtained.
By using such a motor 7 having a permanent magnet, a short-circuit brake can be applied during outside wind to suppress an increase in bus voltage, and an operating current can be reduced during normal operation, thereby improving efficiency. Can be planned.

In addition, as shown in FIGS. 1 and 2, the motor 7 in the present embodiment is attached to the propeller fan 108F, so that when the outside air flows into the outdoor unit 117, the outer surface of the motor 7, for example, the rotating shaft Wind flows in the direction parallel to.
For this reason, a hole is formed in the fan boss of the propeller fan 108F (not shown), or the fan boss does not cover the motor 7 (not shown). Further, fins are attached to the outside of the motor 7 (not shown). By adopting such a heat dissipation structure, the amount of heat exchange between the motor 7 and the air during outside wind increases, and the motor 7 that generates heat due to a short-circuit current during outside wind can be cooled. Temperature rise can be reduced.
Note that the fan boss hole of the propeller fan 108F, the structure where the fan boss of the propeller fan 108F does not cover the motor 7, or the fin outside the motor 7 corresponds to the heat radiating means in the present invention.

FIG. 13 is a diagram showing a temperature rise inside the motor during short-circuit braking. FIG. 13 shows the result of measuring the saturation temperature value when the motor 7 is rotated at high speed during short-circuit braking and the internal temperature of the motor near the rotor 9 rises to saturation.
By taking measures against heat dissipation of the propeller fan 108F and the motor 7 as described above, the saturation temperature of the motor 7 does not reach the demagnetization temperature even at the maximum reached rotational speed or more that is assumed during external wind, as shown in FIG.
Thus, the temperature increase of the motor 7 can be reduced by using a heat dissipation structure. That is, the temperature of the rotor 9 and the permanent magnet that are in thermal contact with the outer shell of the motor 7 through the structural parts of the motor 7 can also be reduced, the reduction of the coercive force of the permanent magnet is suppressed, and the demagnetization resistance of the motor 7 is improved. It is possible.
In order to further increase the cooling effect, it is effective to increase the contact area by using a mold resin or metal having a low thermal resistance as the structure.

FIG. 14 is a diagram showing the BH characteristics of a permanent magnet whose coercive force increases with increasing temperature. FIG. 14 shows the BH characteristics of a permanent magnet whose coercive force increases with increasing temperature, such as a ferrite magnet.
As shown in FIG. 14, for example, the coercive force at −60 ° C. is about 160 kA / m, whereas the coercive force at 100 ° C. is about 320 kA / m, and the coercive force increases about twice as the temperature rises. .
When the rotor 9 using a permanent magnet whose coercive force increases with respect to the temperature rise such as a ferrite magnet is used, the demagnetization resistance increases when the temperature rises due to the short-circuit brake current.
For this reason, the winding current during normal operation can be reduced without taking measures for heat dissipation as described above, the loss of the inverter circuit 5 can be reduced, the efficiency of the air conditioner can be improved, and the heat dissipation of the inverter circuit 5 can be reduced. The fin size can be reduced.
However, it is necessary to design the heat dissipation so that the temperature of the permanent magnet does not become the Curie temperature.

In the first embodiment, the case of the motor 7 having the rotor 9 using a permanent magnet has been described. However, the motor 7 may use a permanent magnet for the stator.
FIG. 15 is a structural diagram of a motor using a permanent magnet in the stator. As shown in FIG. 15, a rotor core 61 made of an electromagnetic steel plate is used as a rotor, and a permanent magnet 62 is included in a stator core 63. With such a structure, the magnetic flux generated by the winding current passes mainly through the stator core 63 side having a low magnetic resistance, and an excessive magnetic flux is not applied to the permanent magnet 62. With the motor 7 having such a structure, the demagnetization resistance can be increased, and the demagnetization current due to the short-circuit brake current is not a design constraint, and the loss of the air conditioner can be reduced.

Embodiment 2. FIG.
FIG. 5 is a circuit diagram of a motor drive control device according to Embodiment 2 of the present invention. In FIG. 5, the motor drive control device 110 according to the second embodiment is connected by the wiring 131 in addition to the configuration of the motor drive control device 110 according to the first embodiment, and consumes power generated by the electromotive force of the motor 7. A brake resistor 130 as a means and a semiconductor switch element 15 for controlling energization to the brake resistor 130 are provided.

  Other configurations are the same as those of the first embodiment. The relationship between the rotation speed of the propeller fan 108F of the outdoor unit 117 and the line voltage (bus voltage) generated by the electromotive force of the motor 7 is the same as the operation described with reference to FIG. Further, in the motor 7 according to the second embodiment, similarly to the first embodiment, the line voltage becomes higher than the withstand voltage of the electrolytic capacitor 4 under the maximum outside wind condition as shown by the thick line in FIG. A motor 7 that generates electric power is used.

  With this configuration, in Embodiment 2 of the present invention, for example, when the propeller fan 108F of the outdoor unit 117 is rotated by outside wind or the like while the operation of the motor 7 is stopped, the rotor 9 of the motor 7 is rotationally driven. An electromotive force is induced. Then, the line voltage of the motor 7 is applied between the terminals of the electrolytic capacitor 4 via the inverter circuit 5, and the bus voltage rises. At this time, when the bus voltage detected by the bus voltage detecting means 13 exceeds a predetermined value, for example, when it becomes 350V or a predetermined value not exceeding 350V, the sensorless control means and the braking control means 10 A switch pattern other than the zero vector is output as the switch pattern of the circuit 5. Then, the semiconductor switch element 15 is turned on or PWMed, and a regenerative current is caused to flow through the brake resistor 130.

  By such an operation, a regenerative current flows through the winding 8 of the motor 7 to perform regenerative braking of the motor 7, and the regenerative power resulting from the motor electromotive force is consumed by the brake resistor 130, thereby increasing the bus voltage. And the breakdown voltage of the electrolytic capacitor 4 is not exceeded.

  As described above, in the second embodiment, when the bus voltage exceeds a predetermined value, the regenerative current is supplied to the brake resistor 130 to suppress the increase of the bus voltage, which is caused by the electromotive force of the motor 7. Breakdown of the withstand voltage of the motor drive control device 110 can be prevented without adding an expensive switching means such as a relay. Moreover, since the short circuit brake is applied by switching of the switching element 6 which is a semiconductor element, there is no concern about the contact life.

  Further, since the withstand voltage can be protected only by the operation of the motor drive control device 110, the motor drive control device 110 can be protected even when the compressor inverter 102 is stopped by the protection operation.

  In the second embodiment, as shown in FIG. 4, the line voltage of the motor 7 can be 250 V at the maximum rotation speed of 1300 rpm in the actual operation region. For this reason, compared with the conventional motor, the current of the motor at the same output is 117/250, which can be ½ or less. The on-loss of the switching elements 6a to 6f of the inverter circuit 5 is proportional to the square of the current on the FET side and proportional to the current on the diode side. Also, the switching loss has a characteristic that depends on the current. Furthermore, since the loss in the shunt resistor 12 is also proportional to the square of the current, when the same inverter circuit 5 is used with the same output, the inverter loss can be greatly reduced in the second embodiment compared to the conventional motor. It becomes possible.

  In the second embodiment, the same rotor and stator are used, the number of turns of the winding 8 is increased, and the electromotive force of the motor 7 can be increased. Since the inductance of the winding 8 is proportional to the square of the number of turns of the winding 8, it is four times when calculated from the line voltage ratio. Therefore, when driven by the inverter circuit 5, the time change di / dt of the winding current can be reduced by ¼. Therefore, the effect of reducing the noise of the motor 7 generated by the current change can also be obtained. This effect is effective in a fan motor that cannot be soundproofed due to wind path pressure loss. Further, the reduction of di / dt has an effect of reducing the generation of electromagnetic noise. Furthermore, the reduction of di / dt has the effect of reducing the current ripple when driving the inverter and reducing the high-frequency iron loss of the motor 7.

  Further, in the conventional technology, when the motor is opened by the opening / closing means during the outside wind, the motor terminal voltage reaches 769 V under the maximum outside wind condition of 30 m / s, and the opening / closing means, the connection between the motor and the opening / closing means, and the connector Although the withstand voltage is required and becomes extremely expensive, the second embodiment can avoid this.

  Further, in the air conditioner, since the propeller fan 108F of the outdoor unit 117 is made of plastic, when the rotational speed increases due to the external wind and exceeds the limit rotational speed, it is destroyed by centrifugal force. Since this limit point is also in the vicinity of the maximum outside wind condition, even if the drive circuit can be protected by opening the motor or stopping the inverter as in the prior art, it is a problem to ensure the blade breaking resistance. In the second embodiment, when the bus voltage exceeding the withstand voltage is generated, that is, when the rotational speed of the motor 7 exceeds a predetermined value, the regenerative brake is continuously applied, so that the propeller fan 108F reaches the same outside wind speed. Since the number of revolutions can be reduced as compared with motor open trains and inverter stops that do not generate brake torque, when the same propeller fan 108F is used, there is also an effect that the amount of outside wind resistance leading to breakage is increased.

  In the second embodiment, the switching operation of the switching element 6 of the inverter circuit 5 is not turned on during regenerative braking. However, the present invention is not limited to this, and the same effect can be obtained by switching the switching element 6. Needless to say.

Embodiment 3 FIG.
In the first embodiment, a short-circuit current is supplied to the winding 8 of the motor 7 to apply a short-circuit brake and an increase in the bus voltage is suppressed. In the second embodiment, a regenerative current is supplied to the brake resistor 130 to generate the regeneration. Although the brake is applied and the rise in the bus voltage is suppressed, the third embodiment uses both the short-circuit brake and the regenerative brake.

  The configuration of motor drive control apparatus 110 according to the third embodiment is the same as the configuration of the second embodiment. The motor 7 according to the third embodiment also uses the motor 7 that generates the same electromotive force as in the first and second embodiments. In the third embodiment, when the bus voltage exceeds a predetermined value by the same operation as in the first or second embodiment, a zero vector or a pattern other than the zero vector is appropriately used as the switch pattern of the inverter circuit 5. Switch. As a result, it is possible to switch between an operation in which a short-circuit current is applied to the winding 8 of the motor 7 to apply a short-circuit brake and an operation in which a regenerative current is applied to the brake resistor 130 to apply a regenerative brake. It goes without saying that the same effect as in the first or second embodiment can be obtained by such an operation.

Embodiment 4 FIG.
FIG. 6 is a circuit diagram of a motor drive control apparatus according to Embodiment 4 of the present invention. 6, in the motor 7 according to the fourth embodiment, both terminals of the windings 8 of each phase are connected to the output terminals of the inverter circuit 5 respectively. The inverter circuit 5 according to the fourth embodiment includes a switching element 6 at each end of each phase of the winding 8 of the motor 7. That is, as shown in FIG. 6, the inverter circuit 5 includes switching elements 6 a to 6 f connected to one side of each winding 8 of the motor 7 and switching elements 6 a ′ connected to the other end side of each winding 8. 6b ', and each is bridge-connected. Thus, in the fourth embodiment, twelve semiconductor switching elements 6 are used to form six arms. In the fourth embodiment, a MOSFET is used as the switching element 6. Each switching element 6a to 6f ′ includes a high speed diode in parallel in the reverse current direction. The built-in high-speed diode functions to flow a reflux current when the switching elements 6a to 6f ′ are turned off.
Furthermore, the motor 7 according to the fourth embodiment is a motor in which the phase voltage of each winding 8 generated by the rotation under the maximum outside wind condition is equal to or lower than the withstand voltage of the electrolytic capacitor 4, for example, the maximum outside wind condition 30 m / In s, when the rotational speed of the motor 7 is 4000 rpm, a motor having a phase voltage of 350 V is used.

  Other configurations are the same as those of the first embodiment. The relationship between the rotation speed of the propeller fan 108F of the outdoor unit 117 and the line voltage (bus voltage) generated by the electromotive force of the motor 7 is the same as the operation described with reference to FIG.

  With this configuration, in the fourth embodiment of the present invention, the motor 7 is connected to the inverter circuit 5 for each phase winding 8, so that, for example, when the operation of the motor 7 is stopped, Even if the propeller fan 108F of the outdoor unit 117 rotates, the bus voltage does not exceed the withstand voltage (350V) of the electrolytic capacitor 4.

  Further, since the motor 7 is connected to the inverter circuit 5 for each phase winding 8, a voltage (phase voltage) induced in each winding 8 is applied between the terminals of the electrolytic capacitor 4. As a result, for example, as shown in FIG. 4, at a maximum rotation speed of 1300 rpm in the actual operation range, a voltage corresponding to the line voltage of the motor 7 according to the fourth embodiment with respect to the line voltage 114 V of the conventional motor. (Phase voltage of the winding 8) is generated approximately 197V, which is 1.73 times (sqrt3 times).

  As described above, in the fourth embodiment, since the inverter circuit 5 has the switching elements 6 at both ends of each phase of the winding 8 of the motor 7, the motor at the same output as compared with the conventional motor. The electromotive force can be set to 1.73 times (sqrt3 times), and the current of the motor 7 can be set to 1 / 1.73 (1 / sqrt3). For example, at the maximum rotation speed of 1300 rpm in the actual operation range, the motor current at the same output can be 114/197. The on loss of the switching elements 6a to 6f 'of the inverter circuit 5 is proportional to the square of the current on the FET side and proportional to the current on the diode side. Also, the switching loss has a characteristic that depends on the current. Furthermore, since the loss in the shunt resistor 12 is also proportional to the square of the current, when the same inverter circuit 5 is used with the same output, the fourth embodiment can greatly reduce the inverter loss as compared with the conventional motor. It becomes possible.

  In the fourth embodiment, breakdown of the motor drive control device 110 due to the electromotive force of the motor 7 can be prevented without adding an expensive switching means such as a relay.

  Further, since the withstand voltage can be protected only by the operation of the motor drive control device 110, the motor drive control device 110 can be protected even when the compressor inverter 102 is stopped by the protection operation.

  In the fourth embodiment, the same rotor or stator is used, the number of turns of the winding 8 is increased, and the electromotive force of the motor 7 can be increased. Since the inductance of the winding 8 is proportional to the square of the number of turns of the winding 8, it is tripled when calculated from the line voltage ratio. Therefore, when driven by the inverter circuit 5, the time change di / dt of the winding current can be reduced by 1/3. Therefore, the effect of reducing the noise of the motor 7 generated by the current change can also be obtained. This effect is effective in a fan motor that cannot be soundproofed due to wind path pressure loss. Further, the reduction of di / dt has an effect of reducing the generation of electromagnetic noise. Furthermore, the reduction of di / dt has the effect of reducing the current ripple when driving the inverter and reducing the high-frequency iron loss of the motor 7.

  Further, in the conventional technology, when the motor is opened by the opening / closing means during the outside wind, the motor terminal voltage reaches 769 V under the maximum outside wind condition of 30 m / s, and the opening / closing means, the connection between the motor and the opening / closing means, and the connector Although the withstand voltage is required and becomes extremely expensive, the fourth embodiment can avoid this.

  Moreover, in this Embodiment 4, since the brake operation by a short circuit current or a regenerative current is not performed, there is no design restriction with respect to the demagnetization of the motor 7 by a short circuit current or a regenerative current.

Embodiment 5 FIG.
7 to 9 are circuit diagrams of the motor drive control device according to the fifth embodiment of the present invention. 7 to 9, the motor 7 according to the fifth embodiment has a three-phase winding 8, and one terminal of each phase winding 8 is connected to the output terminal of the inverter circuit 5. ing. The other terminal of the winding 8 is connected to the opening / closing means 81. By using the opening / closing means 81, switching between Δ connection and Y connection of the winding 8 or switching between the inverter circuit 5 and the winding 8 is possible. That is, the opening / closing means 81 constitutes a switching means for switching the winding 8 of the motor 7 between the Y connection and the Δ connection, and an opening / closing means for disconnecting the connection on one side of the winding 8.
Further, the motor 7 according to the fifth embodiment is a motor in which the phase voltage of each winding 8 generated by the rotation under the maximum outside wind condition is equal to or lower than the withstand voltage of the electrolytic capacitor 4, for example, the maximum outside wind condition 30 m / In s, when the rotational speed of the motor 7 is 4000 rpm, a motor having a phase voltage of 350 V is used.

  Other configurations are the same as those of the first embodiment. The relationship between the rotation speed of the propeller fan 108F of the outdoor unit 117 and the line voltage (bus voltage) generated by the electromotive force of the motor 7 is the same as the operation described with reference to FIG. With this configuration, in the fifth embodiment of the present invention, the Y connection and the Δ connection of the winding 8 are switched or the winding 8 and the inverter circuit 5 are opened.

First, switching between Y connection and Δ connection will be described with reference to FIGS. 7 and 8.
As shown in FIG. 7, for example, during operation of the motor 7, the sensorless control unit and the braking control unit 10 operate the opening / closing unit 81 to switch the winding of the motor 7 to the Y connection. In this case, the connection is the same as that of the conventional motor.

  On the other hand, as shown in FIG. 8, for example, when the operation of the motor 7 is stopped, the sensorless control means and the braking control means 10 operate the opening / closing means 81 to switch the winding of the motor 7 to Δ connection. In this case, when a motor electromotive force is generated due to rotation by the external wind, a phase voltage induced in each winding 8 is applied between the terminals of the electrolytic capacitor 4. Accordingly, the voltage applied between the terminals of the electrolytic capacitor 4 of the inverter circuit 5 can be 1 / 1.73 (1 / sqrt3) at the time of Y connection.

  As a result, for example, when the rotational speed of the motor 7 is 4000 rpm under the maximum outside wind condition of 30 m / s, a motor with a phase voltage of the motor 7 of 350 V can be used. At several 1300 rpm, it is possible to generate approximately 197 V, which is 1.73 times (sqrt 3 times) the phase voltage at Δ connection, with respect to the line voltage 114 V at Y connection. Further, at the time of Δ connection, even if the propeller fan 108F of the outdoor unit 117 rotates due to the maximum outside wind condition, the bus voltage does not exceed the withstand voltage (350V) of the electrolytic capacitor 4.

Next, the opening of the winding 8 and the inverter circuit 5 will be described.
As shown in FIG. 9, for example, when the operation of the motor 7 is stopped, the sensorless control means and the braking control means 10 operate the opening / closing means 81 to open the windings 8 of each phase, and the terminals of the inverter circuit 5. In addition, the voltage due to the motor electromotive force during the external wind is not applied. As described above, when the winding 8 of the motor 7 and the inverter circuit 5 are opened, the voltage due to the electromotive force of the motor 7 is not applied between the terminals (bus voltage) of the electrolytic capacitor 4.

  As described above, in the fifth embodiment, for example, when the operation of the motor 7 is stopped, the opening / closing means 81 is operated to open the Δ connection or the winding 8 as shown in FIG. 8 or FIG. Thus, as shown in FIG. 7, compared with the state at the time of Y connection, the voltage applied between the terminals of the inverter circuit 5 due to the electromotive force caused by the external wind can be reduced or eliminated.

  In the fifth embodiment, the voltage applied between the terminals of the electrolytic capacitor 4 of the inverter circuit 5 can be 1 / 1.73 (1 / sqrt3) at the time of Y connection. The number of turns can be increased to 1.73 times or more, and the motor current can be reduced.

  Further, by switching the winding 8 of the motor 7 to the Δ connection, the motor electromotive force at the same output is 1.73 times (sqrt 3 times) compared to the Y connection, and the current of the motor 7 is reduced to 1/73. (1 / sqrt3). For example, at the maximum rotation speed of 1300 rpm in the actual operation range, the motor current at the same output can be 114/197. The on-loss of the switching elements 6a to 6f of the inverter circuit 5 is proportional to the square of the current on the FET side and proportional to the current on the diode side. Also, the switching loss has a characteristic that depends on the current. Furthermore, since the loss in the shunt resistor 12 is also proportional to the square of the current, when the same inverter circuit 5 is used with the same output, the fifth embodiment can greatly reduce the inverter loss as compared with the conventional motor. It becomes possible.

  Further, since the breakdown voltage can be protected only by the operation of the opening / closing means 81 of the motor drive control device 110, the motor drive control device 110 can be protected even when the compressor inverter 102 is stopped by the protection operation.

  In the fifth embodiment, the same rotor or stator is used, the number of turns of the winding 8 is increased, and the electromotive force of the motor 7 can be increased. Since the inductance of the winding 8 is proportional to the square of the number of turns of the winding 8, it is tripled when calculated from the line voltage ratio. Therefore, when driven by the inverter circuit 5, the time change di / dt of the winding current can be reduced by 1/3. Therefore, the effect of reducing the noise of the motor 7 generated by the current change can also be obtained. This effect is effective in a fan motor that cannot be soundproofed due to wind path pressure loss. Further, the reduction of di / dt has an effect of reducing the generation of electromagnetic noise. Furthermore, the reduction of di / dt has the effect of reducing the current ripple when driving the inverter and reducing the high-frequency iron loss of the motor 7.

  Moreover, in this Embodiment 5, since the brake operation by a short circuit current or a regenerative current is not performed, there is no design restriction with respect to the demagnetization of the motor 7 by a short circuit current or a regenerative current.

Embodiment 6 FIG.
In the first to fifth embodiments, the method of electrically protecting the drive circuit such as the operation of the inverter circuit 5 has been described. However, the motor drive control device 110 according to the sixth embodiment is the same as the first embodiment. In addition to the configurations of ˜5, mechanical braking means for increasing the rotational load of the motor and a stopper for stopping the rotation of the propeller fan 108F are further provided.

  With this configuration, in the sixth embodiment, when the propeller fan 108F is rotated by the external wind and the electromotive force of the motor 7 generated by the rotation of the propeller fan 108F exceeds a predetermined value, the mechanical braking means And the electromotive force of the motor 7 is lowered. Further, when the operation of the motor 7 is stopped, the stopper is operated so that the electromotive force of the motor 7 is not generated by the rotation of the propeller fan 108F. By such an operation, it is possible to suppress the generation of the motor electromotive force due to the rotation by the external wind, and by the increase in the number of turns of the winding 8 of the motor 7 as in the effects of the first to fifth embodiments. Needless to say, an effect may be obtained.

  Note that only one of the mechanical braking means and the stopper described above may be provided, or may be used in combination. Needless to say, in any of the configurations of the first to fifth embodiments described above, it is possible to suppress an increase in the bus voltage by using the mechanical braking means and the stopper together.

Embodiment 7 FIG.
In the first to fifth embodiments, the method of electrically protecting the drive circuit such as the operation of the inverter circuit 5 has been described. However, the motor drive control device 110 according to the sixth embodiment is the same as the first embodiment. In addition to the configurations of ˜5, the shape of the propeller fan 108F is deformed according to the wind speed, and the fan shape deforming means for reducing the rotational force of the propeller fan 108F or the rotational force of the propeller fan 108F is provided in the air passage. Further provided is a damper shutter which is a wind path shape deforming means.

  With this configuration, in the seventh embodiment, when the propeller fan 108F is rotated by the external wind and the electromotive force of the motor 7 generated by the rotation of the propeller fan 108F exceeds a predetermined value, the fan shape deforming means Or / and the damper shutter is operated to reduce the electromotive force of the motor 7. By such an operation, it is possible to suppress the generation of the motor electromotive force due to the rotation by the external wind, and by the increase in the number of turns of the winding 8 of the motor 7 as in the effects of the first to fifth embodiments. Needless to say, an effect may be obtained.

  Note that the fan shape deforming means and the damper shutter described above may be provided with either one or both of them. Needless to say, in any of the configurations of the first to fifth embodiments described above, the fan shape deforming means and the damper shutter can be used together to suppress an increase in the bus voltage. Furthermore, it goes without saying that the increase of the bus voltage can be suppressed by using the mechanical braking means and the stopper described in the sixth embodiment.

Embodiment 8 FIG.
In the first to fifth embodiments, the case where the motor 7 and the motor drive control device 110 are arranged at different locations has been described. However, all or a part of each means constituting the motor drive control device 110 is Even if it is built in the motor 7, the same effect can be obtained. With this configuration, heat generated by the switching element 6 of the inverter circuit 5, the brake resistor 130, the semiconductor switch element 15 that controls the regenerative current, etc. can be radiated into the motor 7. There is an effect that can be done.

Embodiment 9 FIG.
FIG. 10 is a schematic configuration diagram schematically showing a cross section of a ventilation fan according to Embodiment 9 of the present invention. In FIG. 10, the ventilation fan 200 includes a metal casing 201, a sirocco fan 202, a ventilation fan grill 203, and a metal electrical product BOX 204. The ventilation fan 200 is attached to the ceiling wall 220. The sirocco fan 202 of the ventilation fan 200 is connected to the rotor shaft 71 of the motor 7 of the first to eighth embodiments described above, and is rotationally driven by the motor drive control device 110 described in the first to eighth embodiments. The Needless to say, even when the sirocco fan 202 of the ventilation fan 200 is rotated by the outside wind, the same effects as those of the first to eighth embodiments can be obtained by such a configuration.

  In the ninth embodiment, similarly to the first embodiment, the demagnetization resistance of the permanent magnet of the motor 7 may be improved. That is, the motor 7 may include a rotor having a permanent magnet whose coercive force decreases with increasing temperature, and may include a heat radiating unit that radiates the heat of the motor. Alternatively, the motor 7 may include a rotor having a permanent magnet whose coercive force increases with temperature rise. Moreover, you may make it the motor 7 use a permanent magnet for a stator. It goes without saying that the same effect as in the first embodiment can be obtained by such a configuration.

Embodiment 10 FIG.
FIG. 11 is a schematic configuration diagram of a heat pump type hot water supply apparatus according to Embodiment 10 of the present invention. In FIG. 11, a heat pump type water heater includes a compressor 301, a heating heat exchanger 302, a throttle 303, an endothermic heat exchanger 304, a circulation pipe 307 that sequentially connects them, and a blower fan 305 for the endothermic heat exchanger 304. , And an endothermic heat exchanger temperature sensor 311 installed on the outlet side of the endothermic heat exchanger 304. Further, the hot water storage tank 306 is connected to the heating heat exchanger 302 by a circulation pipe 308, heat is exchanged by the circulation pipe 308 passing through the heating heat exchanger 302, and the heated hot water is stored from the upper part of the hot water storage tank 306. The hot water storage tank 306 is supplied with water from a water supply pipe 309. And the ventilation fan 305 of this heat pump type water heater is connected to the motor 7 of the first to eighth embodiments described above, and is rotationally driven by the motor drive control device 110 described in the first to eighth embodiments. . Needless to say, with such a configuration, even when the blower fan 305 of the heat pump type water heater is rotated by outside air, the same effects as those of the first to eighth embodiments described above can be obtained.

  In the tenth embodiment, the demagnetization resistance of the permanent magnet of the motor 7 may be improved as in the first embodiment. That is, the motor 7 may include a rotor having a permanent magnet whose coercive force decreases with increasing temperature, and may include a heat radiating unit that radiates the heat of the motor. Alternatively, the motor 7 may include a rotor having a permanent magnet whose coercive force increases with temperature rise. Moreover, you may make it the motor 7 use a permanent magnet for a stator. It goes without saying that the same effect as in the first embodiment can be obtained by such a configuration.

  DESCRIPTION OF SYMBOLS 1 Commercial power supply, 2 Rectifier circuit, 3 Rectifier diode, 4 Electrolytic capacitor, 5 Inverter circuit, 6 Switching element, 7 Motor, 8 Winding, 9 Rotor, 10 Sensorless control means and braking control means, 11 Current detection means, 12 Shunt resistor, 13 bus voltage detection means, 15 semiconductor switch element, 61 rotor core, 62 permanent magnet, 63 stator core, 64 stator winding, 71 rotor shaft, 81 opening / closing means, 102 compressor inverter, 103 compressor, 104 four-way valve, 105 outdoor heat exchanger, 106 expansion valve, 107 indoor heat exchanger, 108 outdoor fan, 108F propeller fan, 109 indoor fan, 110 motor drive control device, 112 speed control circuit, 113 air conditioner control unit, 114 light receiving unit, 115 abnormality display section, 16 Infrared remote control, 117 Outdoor unit, 130 Brake resistor, 131 Wiring, 200 Ventilation fan, 201 Metal housing, 202 Sirocco fan, 203 Ventilation fan grill, 204 Electrical box, 220 Ceiling wall, 301 Compressor, 302 Heat exchange 303, throttle part, 304 endothermic heat exchanger, 305 blower fan, 306 hot water storage tank, 307 circulation pipe, 308 circulation pipe, 309 water supply pipe, 311 endothermic heat exchange part temperature sensor.

Claims (14)

A motor drive control device that rotates a fan and drives a motor in which one end of each phase of the winding is connected,
An inverter circuit for converting a DC voltage into an AC voltage and applying the same to the motor;
Control means for controlling the operation of the motor by controlling the inverter circuit;
A bus voltage detecting means for detecting a voltage of a power line for supplying power to the inverter circuit;
The motor generates an electromotive force in which the line voltage is equal to or higher than the withstand voltage of the inverter circuit when the outside wind condition in which the rotation speed of the motor is higher than the rotation speed in the actual operation range ,
The inverter circuit has a switching element at one end of each phase of the winding,
When the bus voltage detection means detects that the voltage of the power line due to the electromotive force of the motor has become a certain voltage or higher,
The motor drive control device, wherein the control means controls a switch pattern of the switching element to short-circuit one end of each phase of the winding of the motor via the switching element. An opening / closing means for opening / closing a connection on at least one side of the connection between the windings of the motor;
2. The motor drive control device according to claim 1, wherein when the operation of the motor is stopped, the control unit operates the opening / closing unit to disconnect the connection on one side of the winding of the motor from the inverter circuit. The motor drive control device according to claim 2, wherein at least one of the inverter circuit, the control unit, and the opening / closing unit is built in the motor. Mechanical braking means for increasing the rotational load of the motor,
The control means operates the mechanical braking means when the fan is rotated by the external wind and the electromotive force of the motor generated by the rotation of the fan exceeds a predetermined value. The motor drive control device according to claim 1, wherein the motor drive control device is reduced. A stopper for stopping the rotation of the fan;
5. The motor according to claim 1, wherein the control unit operates the stopper when the operation of the motor is stopped, and does not generate an electromotive force of the motor due to rotation of the fan. Drive control device. Fan shape deformation means for reducing the rotational force of the fan is further provided,
The control means operates the fan shape deforming means when the fan is rotated by an external wind and the electromotive force of the motor generated by the rotation of the fan exceeds a predetermined value, and the electromotive force of the motor is The motor drive control device according to any one of claims 1 to 5, wherein the motor drive control device is reduced. It further comprises air path shape deforming means for reducing the rotational force of the fan,
The control means operates the wind path shape deforming means when the fan rotates due to outside wind and the electromotive force of the motor generated by the rotation of the fan exceeds a predetermined value, and the electromotive force of the motor The motor drive control device according to claim 1, wherein the motor drive control device according to claim 1 is reduced. A motor that rotates the fan;
An air conditioner comprising the motor drive control device according to any one of claims 1 to 7. A motor that rotates the fan;
A ventilation fan comprising the motor drive control device according to any one of claims 1 to 7. A motor that rotates the fan;
A heat pump type water heater comprising the motor drive control device according to any one of claims 1 to 7. A heat dissipating means for dissipating the heat of the motor;
The air conditioner according to claim 8, wherein the motor includes a rotor having a permanent magnet whose coercive force decreases with increasing temperature. The air conditioner according to claim 8, wherein the motor includes a rotor having a permanent magnet whose coercive force increases with increasing temperature. The air conditioner according to claim 8, wherein the motor includes a stator having a permanent magnet. The heat dissipation means is
The fan is rotated by the outside wind, the heat of the motor due to the electromotive force of the motor generated by the rotation of the fan is radiated by the outside wind,
The air conditioner according to claim 11, wherein an internal temperature of the motor does not exceed a demagnetizing temperature of the permanent magnet.

Images