JP2012159270A - Control device, and heat pump device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly cope with a starting-specific situation different from a steady state, in a starting state of a motor.SOLUTION: A voltage detecting section and a current detecting section detect at least one of overvoltage of an invertor circuit and overcurrent of an outdoor fan motor. With respect to detections of malfunction (S10a, S20a) in the voltage detecting section and the current detecting section and controls in malfunction (S10b, S20b) of an air conditioning device 10 according thereto, a control section implements them along a first sequence (S10) in the steady state of the outdoor fan motor, and along a second sequence (S20) different from the first sequence in the starting state before the steady state.

Description

  The present invention relates to a drive control device including a motor and a heat pump device including a fan motor.

  In heat pump devices, demand for brushless DC motors (hereinafter referred to as brushless DC motors), such as fan motors, which have high efficiency, long life, and low electrical noise and mechanical noise, is increasing. Such a multiphase motor such as a brushless DC motor is generally driven by being supplied with electric power from an inverter with high energy efficiency.

  In a heat pump device, even if no power is supplied from such an inverter to the fan motor, the fan rotates due to the external airflow generated in the environment where the heat pump device is installed, and the fan motor follows the rotation of the fan. May be rotated.

  When the fan motor, which is a brushless DC motor, is rotated by an external force such as an external airflow generated around the outdoor unit, the fan motor functions as a generator, and power is supplied from the fan motor to the inverter. In this way, when the fan motor is started from a state where power is supplied from the fan motor by an external force, an overvoltage may be generated in the inverter, an overcurrent may be generated in the fan motor, or the fan motor may be stepped out. is there. If such a phenomenon peculiar to starting is considered as an abnormal situation and the same handling as in the inverter overvoltage, fan motor overcurrent or step-out in a steady state, the start of the heat pump device will be delayed or excessive heat pump device There may be a situation where the user is protected and inconvenienced the user. Thus, for example, in an outdoor unit of an air conditioner described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2003-148788), the rotational direction and the rotational speed of a fan are detected from position detection means connected to the motor terminal voltage. When the necessary air volume can be obtained by estimating the air flow through the heat exchanger, the operation of the outdoor unit is started without operating the fan motor.

  However, in the outdoor unit described in Patent Document 1 or the like, a circuit for detecting the motor terminal voltage is provided in order to exclusively detect the motor rotation speed, or the detection result of the detection circuit is input to the control unit. It is necessary to provide a dedicated detection terminal for the control in the control unit. If these additional circuits are provided to control the outdoor unit in consideration of the rotation of the fan motor before starting due to the external airflow, the control unit for the outdoor unit becomes expensive.

  An object of the present invention is to appropriately cope with a situation unique to starting at a time different from the steady state without providing an expensive additional circuit in a motor starting state that is different from the steady state of the motor driving operation. It is to make it.

  A control device according to a first aspect of the present invention is a control device for a drive device including a motor to which drive power is supplied by an inverter, and detects an abnormality by detecting an abnormality in at least one of the inverter and the motor. The detection unit, the abnormality detection in the detection unit, and the control at the time of abnormality of the drive device corresponding thereto are performed along the first sequence in the steady state of the motor drive operation, and the first sequence in the start state before the steady state is And a control unit that performs along different second sequences.

  According to the control device according to the first aspect, the abnormality is detected along the first sequence in the steady state of the motor and the abnormality control of the drive device is performed in accordance with the abnormality, while the motor is in the starting state along the second sequence. Abnormality detection and control of the drive device in accordance with the abnormality are performed. As described above, detection and control are performed along the first sequence and the second sequence which are different in the steady state and the start state, respectively. The contents of time control can be varied.

  Here, the abnormal time control of the drive device may include the abnormal time control of the motor, but includes the abnormal time control of devices other than the motor inside the drive device.

  The control device according to the second aspect of the present invention is the control device according to the first aspect. In the control device according to the first aspect, even when the control unit starts abnormality control in the first sequence due to abnormality detection in the detection unit, Do not start time control.

  According to the control device according to the second aspect, the first sequence and the second sequence are different for abnormality detection, and even when the abnormal control is started in the first sequence, the abnormal control is not started in the second sequence. Even if the conditions for performing the abnormal control in the first sequence are satisfied, it is possible that the abnormal control is not performed in the second sequence.

  In the control device according to the third aspect of the present invention, in the control device according to the first or second aspect, the abnormality detected by the detection unit is at least one of an inverter overvoltage, a motor overcurrent, and a motor step-out. One.

  According to the control device according to the third aspect, the inverter abnormality can be detected by detecting the inverter overvoltage, and the motor abnormality can be detected by detecting at least one of the motor overcurrent and the motor step-out. Therefore, the abnormality detection at the detection unit can be easily performed.

  A control device according to a fourth aspect of the present invention is the control device according to the third aspect, wherein the control unit includes a threshold voltage for determining overvoltage, a threshold current for determining overcurrent of the motor, and a threshold for determining step-out. If at least one is exceeded, even when the abnormal control is performed in the steady state, the abnormal control is not performed in the starting state.

  According to the control device of the fourth aspect, in a steady state, when at least one of a threshold voltage for determining an overvoltage, a threshold current for determining an overcurrent of a motor, and a threshold for determining a step-out is exceeded, control in an abnormal state is performed. The first sequence of performing is performed. However, in the start-up state, even if at least one of the threshold voltage, the threshold current, and the threshold for determining the step-out is exceeded, the second sequence in which the abnormality control is not performed is followed.

The control device according to a fifth aspect of the present invention is the control device according to any one of the second to fourth aspects, wherein the control unit is more than the first detection criterion for the detection unit to perform abnormality detection in the first sequence. By using the relaxed second detection criterion in the second sequence, even when the abnormal control is started in the first sequence, the abnormal control is not started in the second sequence.

  According to the control device according to the fifth aspect, abnormality detection is controlled in the first sequence by a simple setting using the first detection criterion in the first sequence and the second detection criterion in the second sequence for determining abnormality detection. Even if the conditions for performing the above are satisfied, it is possible that the abnormal control is not performed in the second sequence.

A control device according to a sixth aspect of the present invention is the control device according to any one of the second to fifth aspects, wherein the control unit stops or invalidates the abnormality detection in the detection unit in the second sequence. Even when the abnormal control is performed in the first sequence, the abnormal control is not performed in the second sequence.

  According to the control device according to the sixth aspect, even when the abnormality detection is performed in the detection unit and the abnormality control is performed in the first sequence, the abnormality detection of the detection unit is stopped or invalidated in the second sequence. With this simple configuration, even when the conditions for performing the abnormal control in the first sequence are satisfied, it is possible that the abnormal control is not performed in the second sequence.

  A control device according to a seventh aspect of the present invention is the control device according to any one of the first to sixth aspects, wherein the control unit is configured to execute the first sequence and the second sequence if the rotational speed of the motor exceeds a predetermined value. In any of the sequences, the motor drive is stopped.

  According to the control device according to the seventh aspect, the abnormality detection in the detection unit and the abnormality control of the driving device corresponding thereto are performed along the first sequence or along the second sequence. When the rotational speed exceeds a predetermined value, the motor is stopped. Therefore, the motor does not rotate beyond the predetermined value by an external force regardless of whether it is along the first sequence or the second sequence.

  A control device according to an eighth aspect of the present invention is the control device according to any one of the first to seventh aspects, wherein the control unit performs rotor position sensorless control of the motor and shifts to a rotor position sensorless operation in which the motor is stable. The determined state is determined as a steady state.

  According to the control device of the eighth aspect, since the rotor position sensorless control of the motor is performed, a stable rotor can be obtained when the fan motor is started in an external force state (in other words, heat exchange performance can be obtained). Although there is a high possibility that abnormality detection will occur in the starting state until the shift to the position sensorless operation, the system of the heat pump device is stopped without reporting an abnormality by applying the second sequence different from the steady state. There is no.

  In the control device according to the ninth aspect of the present invention, in any one of the control devices according to the first to eighth aspects, the control unit determines that the steady state is reached when the rotational speed of the motor reaches the command value. .

  According to the control device according to the ninth aspect, since the case where the rotational speed of the motor reaches the command value is determined as the steady state, the determination of the steady state can be performed easily and reliably and the original abnormality can be surely confirmed. Can be detected.

  A heat pump device according to a tenth aspect of the present invention detects an abnormality by detecting an abnormality in at least one of a fan motor, an inverter and a fan motor, which is supplied with driving power by a fan and an inverter, and drives the fan. The detection of the abnormality in the detection unit and the detection unit and the control at the time of abnormality of the device are performed in accordance with the first sequence in the steady state of the fan motor, and different from the first sequence in the starting state before the steady state. And a control device having a control unit that performs in accordance with two sequences.

  According to the heat pump apparatus according to the tenth aspect, abnormality detection is performed along the first sequence in the steady state of the fan motor and the abnormality control of the heat pump apparatus is performed in accordance with the abnormality, while abnormality is detected along the second sequence in the starting state. Detection and abnormal control of the heat pump device are performed accordingly. As described above, detection and control are performed according to the first sequence and the second sequence which are different in the steady state and the start state, respectively, so that the judgment criteria for abnormality detection are different between the steady state and the start state. The contents of time control can be varied.

  Here, the abnormal control of the device may include the abnormal control of the fan motor, but includes the abnormal control of the devices other than the fan motor in the heat pump device.

  In the heat pump device according to an eleventh aspect of the present invention, in the heat pump device according to the tenth aspect, the abnormality detected by the detection unit is at least one of an inverter overvoltage, a fan motor overcurrent, and a fan motor step-out. is there.

  According to the heat pump device of the eleventh aspect, the abnormality of the inverter can be detected by detecting the overvoltage of the inverter, and the abnormality of the fan motor can be detected by detecting at least one of the overcurrent of the fan motor and the step-out of the fan motor. Therefore, it is possible to easily detect an abnormality in the detection unit.

  A heat pump device according to a twelfth aspect of the present invention is the heat pump device according to the tenth aspect or the eleventh aspect, further comprising a refrigerant circuit that circulates a refrigerant in order to exchange heat with an air flow passing through the fan, The unit does not start the abnormal time control for the operation of the refrigerant circuit in the second sequence even when starting the abnormal time control for the operation of the refrigerant circuit in the first sequence.

  According to the heat pump device of the twelfth aspect, when there is a flow of air flow necessary for the refrigerant circuit in the starting state, the abnormality control of the refrigerant circuit operation is not started by detecting the abnormality of the fan motor. In such a case, it is possible to prevent the abnormal time control performed in the first sequence from starting in the second sequence.

  The heat pump device according to a thirteenth aspect of the present invention is the heat pump device according to the twelfth aspect, wherein the control unit is stricter than the first condition in the second sequence, unlike the first condition for monitoring the refrigerant circuit in the first sequence. The refrigerant circuit is monitored using the second condition, and it is determined that an abnormality has occurred in the refrigerant circuit when the second condition is satisfied even if the first condition is not satisfied.

  According to the heat pump device according to the thirteenth aspect, even when the abnormal time control is applied to the operation of the refrigerant circuit in the first sequence, the abnormal time control is performed for the operation of the refrigerant circuit in the second sequence. Since there is no case, the monitoring of the refrigerant circuit under the second condition that is stricter than the first condition of the first sequence can enhance the monitoring when the operation of the refrigerant circuit is not stopped in the second sequence.

  In the heat pump device according to a fourteenth aspect of the present invention, in the heat pump device according to the thirteenth aspect, when the controller determines that the second condition is satisfied and an abnormality has occurred, the refrigerant circuit operates abnormally. Take control.

  According to the heat pump device of the fourteenth aspect, since the control at the time of abnormality of the operation of the refrigerant circuit in the second sequence is performed based on whether or not the second condition is satisfied, when there is a high probability that abnormality of the refrigerant circuit has occurred. Even in the second sequence, the control when the refrigerant circuit is abnormal can be performed.

  In the heat pump apparatus according to the fifteenth aspect of the present invention, in the heat pump apparatus according to the thirteenth aspect or the fourteenth aspect, the number of times the control unit determines that the second condition is satisfied and an abnormality has occurred is a predetermined number. When it exceeds, an abnormal alarm is issued.

  According to the heat pump device according to the fifteenth aspect, the abnormality notification performed by the control unit indicates to the user that the number of times that the second condition is satisfied and an abnormality has occurred is over a predetermined number. I can inform you.

  A heat pump device according to a sixteenth aspect of the present invention is the heat pump device according to any one of the tenth to fifteenth aspects, wherein a fan and a fan motor are installed in the outdoor unit.

  The heat pump device according to the sixteenth aspect can be applied to the case where the fan and the fan motor are installed in an outdoor unit that is easily affected by external force, and the fan and the fan motor are easily affected by outside air. .

  In the control device according to the first aspect of the present invention, the abnormality detection and the control at the time of abnormality of the drive device according to the abnormality detection are determined in the steady state and the starting state by making the first sequence different from the second sequence. It is possible to vary the standard or the contents of the control at the time of abnormality, and in the starting state of the motor, which is different from the steady state of the motor, a situation unique to starting without providing an expensive additional circuit Can be dealt with appropriately.

  In the control device according to the second aspect of the present invention, even when the abnormal state control is performed in the steady state by the simple setting of differentiating the first sequence and the second sequence for abnormality detection, the abnormal state control is performed in the starting state. Thus, it is possible to deal with a situation peculiar to the start-up that does not require the control during the start-up in the start-up state.

  In the control device according to the third aspect of the present invention, the abnormality can be easily detected by the detection unit, and the configuration becomes simple.

  In the control device according to the fourth aspect of the present invention, the abnormality is detected in the starting state by a simple setting in which the first sequence and the second sequence are handled differently with respect to the threshold voltage, the threshold current, and the threshold for judging the step-out. It becomes possible to cope with a situation peculiar to the start-up that does not require time control.

  In the control device according to the fifth aspect of the present invention, there is provided a case in which the first sequence and the second sequence are subjected to abnormal control by providing the first detection criterion of the first sequence and the second detection criterion of the second sequence. This makes it possible to deal with a situation unique to the start-up that does not require the control during the start-up in the start-up state.

  In the control device according to the sixth aspect of the present invention, the control at the time of abnormality is performed in the starting state by a simple configuration in which whether the abnormality detection in the detection unit is stopped or invalidated is switched between the first sequence and the second sequence. It will be possible to deal with situations specific to startup that do not need to be performed.

  In the control device according to the seventh aspect of the present invention, the motor rotation speed does not exceed a predetermined value due to an external force in either the first sequence or the second sequence, and therefore an adverse effect caused by the motor rotation speed exceeding a predetermined value due to the external force. Can be suppressed.

  In the control device according to the eighth aspect of the present invention, there is a high possibility that abnormality detection will occur in the starting state until the operation shifts to stable rotor position sensorless operation. Will increase.

In the control device according to the ninth aspect of the present invention, it is possible to easily and reliably determine the steady state, and to reliably detect the original abnormality, and the configuration of the control device is simplified.

  In the heat pump device according to the tenth aspect of the present invention, the abnormality detection and the abnormal control of the heat pump device according to the abnormality detection are determined by detecting the abnormality in the steady state and the starting state by making the first sequence different from the second sequence. It is possible to vary the standards and the contents of the control at the time of abnormality, and in the starting state of the fan motor, which is different from the steady state of the fan motor, it is peculiar to starting without providing an expensive additional circuit It will be possible to deal appropriately with this situation.

  In the heat pump device according to the eleventh aspect of the present invention, the abnormality can be easily detected by the detection unit, and the configuration of the control device is simplified.

  In the heat pump device according to the twelfth aspect of the present invention, the operation of the refrigerant circuit, which is different from the first sequence, for example, does not stop the operation of the refrigerant circuit by the second sequence by not starting the abnormal time control in the start state. This makes it possible to appropriately deal with the situation specific to the start-up regarding the operation of the fan motor and the refrigerant circuit.

  In the heat pump device according to the thirteenth aspect of the present invention, since the monitoring of the refrigerant circuit is strengthened in the second sequence, an abnormality in the operation of the refrigerant circuit can be detected early.

  In the heat pump device according to the fourteenth aspect of the present invention, the abnormal control of the refrigerant circuit can be performed even in the second sequence depending on the situation, and the wear received by the refrigerant circuit can be reduced.

  In the heat pump device according to the fifteenth aspect of the present invention, it is possible to alert the user of the heat pump device by issuing an abnormality.

  In the heat pump device according to the sixteenth aspect of the present invention, it is possible to appropriately cope with the situation peculiar to starting of the heat pump device in which the fan and the fan motor are installed in the outdoor unit that is easily affected by the outside air.

The front view which shows the external appearance of the air conditioning apparatus which concerns on one Embodiment. The circuit diagram which shows the refrigerant circuit of an air conditioning apparatus, and the outline | summary of the periphery. The block diagram which shows the outline | summary of the control system by a control part. The block diagram which shows the outline | summary of a structure of each motor part of an outdoor unit, and its periphery. The perspective view for demonstrating the internal structure of an outdoor unit. The circuit diagram which shows an outdoor fan motor part, its power supply, and a peripheral circuit. The flowchart which shows the outline of abnormality detection and control at the time of abnormality. The flowchart for demonstrating a 1st sequence. The flowchart for demonstrating a 2nd sequence. The graph for demonstrating the detection of the high voltage | pressure abnormality in a starting state.

  Hereinafter, an air conditioner will be described as an example of a drive device having a motor according to an embodiment of the present invention. This air conditioner has a brushless DC motor corresponding to a motor of a driving device in an outdoor fan motor section.

(1) Outline of Air Conditioner FIG. 1 is a perspective view showing the appearance of a heat pump air conditioner according to an embodiment of the present invention. The air conditioner 10 in FIG. 1 includes an indoor unit 20 and an outdoor unit 30. The outdoor unit 30 is connected to the indoor unit 20 installed indoors by a refrigerant pipe, and constitutes a refrigerant circuit of the air conditioner 10 together with the indoor unit 20. Therefore, the indoor unit 20 and the outdoor unit 30 are communicated with each other by a communication pipe 12 such as a refrigerant pipe or a transmission line.

  FIG. 2 is a circuit diagram showing an outline of the configuration of the air conditioning apparatus 10 of FIG. In order to constitute the refrigerant circuit 14 shown in FIG. 2, the indoor unit 20 is provided with an indoor heat exchanger 21, and the outdoor unit 30 includes a compressor 31, a four-way switching valve 32, an outdoor heat exchanger 33, An electric valve 34 and an accumulator 35 are provided. A first port of a four-way switching valve 32 is connected to the discharge side of the compressor 31. One outlet of the outdoor heat exchanger 33 is connected to the second port of the four-way switching valve 32, the accumulator 35 is connected to the third port, and the refrigerant communication pipe 12b is connected to the fourth port. The four-way switching valve 32 is connected to the first port and the second port as shown by the solid line during cooling and to the third port and the fourth port. On the other hand, at the time of heating, as shown by the broken line, the four-way switching valve 32 is connected to the first port and the fourth port and to the second port and the third port. The other entrance / exit of the outdoor heat exchanger 33 is connected to one entrance / exit of the indoor heat exchanger 21 via the electric valve 34 and the refrigerant communication pipe 12a. The other entrance / exit of the indoor heat exchanger 21 is connected to the refrigerant communication pipe 12b. Further, the suction side of the compressor 31 is connected to the third port of the four-way switching valve 32 via the accumulator 35. The refrigerant circulates in the refrigerant circuit 14.

  At the time of cooling, the four-way switching valve 32 is connected in a solid line, and the refrigerant compressed and discharged by the compressor 31 is sent to the outdoor heat exchanger 33 through the four-way switching valve 32. The refrigerant that has been deprived of heat by exchanging heat with the outside air in the outdoor heat exchanger 33 is sent to the motor-operated valve 34. The motorized valve 34 changes the high-pressure liquid refrigerant into a low-temperature and low-pressure wet steam state. The refrigerant expanded by the electric valve 34 enters the indoor heat exchanger 21 through the refrigerant communication pipe 12a. The refrigerant whose temperature has risen due to heat exchange with room air in the indoor heat exchanger 21 is sent to the four-way switching valve 32 through the refrigerant communication pipe 12a. In the four-way switching valve 32, the refrigerant communication pipe 12a and the accumulator 35 are connected. Therefore, the refrigerant sent from the indoor heat exchanger 21 is sent to the compressor 31 via the accumulator 35.

  During heating, the four-way switching valve 32 is connected in a dotted line, and the refrigerant compressed and discharged by the compressor 31 is sent to the indoor heat exchanger 21. Then, the refrigerant exiting the outdoor heat exchanger 33 is sent to the compressor 31 along a path opposite to that during cooling. That is, the compressor 31, the four-way switching valve 32, the refrigerant communication pipe 12b, the indoor heat exchanger 21, the refrigerant communication pipe 12a, the motor operated valve 34, the outdoor heat exchanger 33, the four-way switching valve 32, the accumulator 35, and the compressor 31. The refrigerant circulates in this order.

  The indoor unit 20 and the outdoor unit 30 include an indoor fan 22 that sends room air to the indoor heat exchanger 21 and an outdoor heat exchanger in order to promote heat exchange in the indoor heat exchanger 21 and the outdoor heat exchanger 33, respectively. A propeller fan 37 for sending outside air to 33 is provided. An indoor fan motor unit 23 and an outdoor fan motor unit 38 for driving the indoor fan 22 and the propeller fan 37 are provided in the indoor unit 20 and the outdoor unit 30, respectively.

(2) Outline of Control System In order to perform the air conditioning operation correctly and efficiently in the air conditioner 10, the indoor unit 20 and the outdoor unit 30 are each provided with an indoor control unit 60 and an outdoor control incorporated in each device. Controlled by the unit 70. FIG. 3 is a block diagram showing an outline of the configuration of the control system. The indoor control unit 60 and the outdoor control unit 70 are connected to each other via the communication line 12c to transmit / receive data to / from each other, and constitute one control device 50. The control device 50 includes a CPU (Central Processing Unit), a memory, peripheral circuits, and the like, and realizes a control function described later by combining these circuits.

  The outdoor unit 30 includes an outdoor heat exchanger temperature sensor 41, a heat exchanger inlet / outlet temperature sensor 42, a suction side temperature sensor 43, a discharge side temperature sensor 44, and a temperature sensor for measuring the temperature of each part of the outdoor unit 30. An outdoor temperature sensor 45 and the like are provided, and temperature values measured by these temperature sensors 41 to 45 are transmitted to the outdoor control unit 70. The outdoor heat exchanger temperature sensor 41 detects the temperature of the refrigerant inside the outdoor heat exchanger 33. The heat exchanger inlet / outlet temperature sensor 42 is provided at the inlet / outlet of the outdoor heat exchanger 33 and measures the temperature of the refrigerant passing between the outdoor heat exchanger 33 and the indoor unit 20. The suction side temperature sensor 43 measures the temperature of the refrigerant sucked into the compressor 31. The discharge side temperature sensor 44 measures the temperature of the refrigerant discharged from the compressor 31. The outside air temperature sensor 45 detects the outside air temperature around the outdoor unit 30.

  The outdoor unit 30 includes a suction side pressure sensor 46 for measuring the pressure of the refrigerant sucked into the compressor 31, a discharge side pressure sensor 47 for measuring the pressure of the refrigerant discharged from the compressor 31, and the like. A pressure sensor is provided. The refrigerant pressure values measured by the suction side pressure sensor 46 and the discharge side pressure sensor 47 are transmitted to the outdoor control unit 70.

  In the outdoor unit 30, a voltage detection unit 81 and a current detection unit 82, which will be described in detail later, are provided, and these are connected to the outdoor control unit 70.

  Further, in the outdoor unit 30, the compressor motor unit 40, the four-way switching valve 32, the electric valve 34, and the outdoor fan motor unit 38 of the compressor 31 are connected to the outdoor control unit 70. The outdoor control unit 70 controls the rotational speed of the compressor motor unit 40 and the outdoor fan motor unit 38, the operation / stop thereof, the switching of the four-way switching valve 32, and the opening degree of the electric valve 34.

  The indoor unit 20 is provided with a liquid side temperature sensor 24 and a gas side temperature sensor 25 for measuring the temperature of the refrigerant at the entrance and exit of the indoor heat exchanger 21, and an indoor temperature sensor 26 for measuring the indoor temperature. Is provided. The temperature values measured by these temperature sensors 24 to 26 are transmitted to the indoor control unit 60. In the indoor unit 20, the indoor fan motor unit 23 of the indoor fan 22, the wind direction adjusting mechanism 27, the display unit 28, and the like are connected to the indoor control unit 60. The indoor controller 60 controls the rotation speed and operation / stop of the indoor fan motor unit 23. The direction of the wind blown into the room is adjusted by the air direction adjusting mechanism 27 changing the angle of a louver (not shown) provided in the indoor unit 20. The indoor control unit 60 outputs a control signal for instructing display to the display unit 28 in order to perform various displays. For example, the control device 50 can cause the display unit 28 to display an abnormality report when an abnormality occurs in the outdoor fan motor unit 38 described later.

(2-1) Control of Each Motor Unit of Outdoor Unit As shown in FIG. 4, the outdoor control unit 70 includes a CPU 71, a memory 72, a timer 73, and peripheral circuits 74 and 75. Peripheral circuits 74 and 75 are partly integrated (IC). The CPU 71 controls the outdoor fan motor unit 38 and the compressor motor unit 40 via the peripheral circuits 74 and 75 according to a command given from the outside or a command stored in the memory 72. The CPU 71 measures the timing at the time of control by the timer 73.

The outdoor fan motor unit 38 is provided with a voltage detection unit 81 and a current detection unit 82. An overvoltage between the DC power supply lines 498 and 499 is detected by the voltage detection unit 81 connected between the DC power supply lines 498 and 499. Such a voltage detection unit 81 is provided with a plurality of detection circuits including, for example, a plurality of resistors connected between the DC power supply lines 498 and 499 and a transistor for detecting a voltage applied to one of the resistors. Consists of.
In such a configuration, an appropriate detection circuit is selected from a plurality of detection circuits that detect an overvoltage with different threshold voltages according to a signal supplied from the peripheral circuit 74. Thereby, the voltage detection unit 81 switches the threshold voltage for detecting the overvoltage, and outputs the detection of the overvoltage to the peripheral circuit 74 when the threshold voltage is exceeded.

  Further, the overcurrent flowing through the outdoor fan motor unit 38 is detected by the current detection unit 82 inserted in series in the DC power supply line 499 on the low voltage side. The current detection unit 82 is a detection circuit including, for example, a shunt resistor inserted in the DC power supply line 499, an amplifier circuit including an operational amplifier that amplifies the voltage across the shunt resistor, and a transistor that detects an output voltage of the amplifier circuit. Composed. In such a detection circuit, for example, an appropriate amplification factor can be selected from a plurality of amplification factors of the operational amplifier by a signal given from the peripheral circuit 74. Thereby, the current detector 82 switches the threshold current for detecting the overcurrent, and outputs the detection of the overcurrent to the peripheral circuit 74 when the threshold current is exceeded.

  The outdoor fan motor unit 38 is provided with a discharge unit 497 and is controlled by the outdoor control unit 70. The discharging unit 497 discharges the smoothing capacitor 496 and adjusts the voltage between the high voltage side DC power supply line 498 and the low voltage side DC power supply line 499.

(3) Structure of outdoor unit As shown in FIG. 1, the outdoor unit 30 has a substantially rectangular parallelepiped shape and is covered with a casing 15. A front plate assembly 16 is disposed on the front surface of the casing 15, and the front plate assembly 16 is provided with a fan outlet 17 at a substantially central portion thereof.

  FIG. 5 shows the outdoor unit 30 with the casing 15 removed. The outdoor heat exchanger 33 is exposed from the back surface of the casing 15 to one side surface. The propeller fan 37 is disposed immediately on the back side of the fan outlet 17, and the outdoor fan motor unit 38 that drives the propeller fan 37 is disposed on the back side of the propeller fan 37. The outside air sucked from the back surface and one side surface of the casing 15 passes through the outdoor heat exchanger 33 and is blown out from the fan outlet 17 on the front surface of the casing 15.

  The airflow blown out from the fan outlet 17 is generated when the propeller fan 37 is driven by the outdoor fan motor 38 and the propeller fan 37 rotates counterclockwise (CCW direction). When the propeller fan 37 is not driven by the outdoor fan motor 38, an external force generated by an external airflow generated outside may act on the propeller fan 37 to generate torque that rotates the propeller fan 37. For example, when an external airflow passes through the fan outlet 17 in the direction of the outdoor heat exchanger 33, the propeller fan 37 rotates clockwise (CW direction) by torque generated in the propeller fan 37 by the external airflow.

(4) Supply of Electric Power to Each Motor Unit of Outdoor Unit FIG. 4 is a block diagram for explaining an outline of control of the motor unit in the outdoor unit. The outdoor unit 30 includes an outdoor fan motor unit 38, a compressor motor unit 40, and rectifier circuits 49A and 49B for supplying DC power thereto. An AC power supply 48 is connected to the rectifier circuits 49A and 49B. The rectifying circuit 49A includes a rectifying unit 491 made of a diode, and a smoothing capacitor 492 connected between the high-voltage side DC power supply line 493 and the low-voltage side DC power supply line 494. The rectifier circuit 49B discharges the smoothing capacitor 496 connected between the high voltage side DC power supply line 498 and the low voltage side DC power supply line 499, and the smoothing capacitor 496. A discharge part 497 is provided. The outdoor fan motor unit 38 includes an outdoor fan motor 38a and an inverter circuit 38b. The compressor motor unit 40 includes a compressor motor 40a and an inverter circuit 40b. As described with reference to FIG. 3, the outdoor fan motor unit 38 and the compressor motor unit 40 are controlled by the outdoor control unit 70.

(4-1) Power Supply to Outdoor Fan Motor Unit FIG. 6 shows a circuit of the main part of the outdoor fan motor 38a and its drive system. The outdoor fan motor 38a shown in FIG. 6 is a brushless DC motor, and performs rotor position sensorless control without a position detection element such as a Hall element. The outdoor fan motor 38a includes a rotor 381 and a stator 382.

  The stator 382 has a star connection in which one ends of the armature coils Lu, Lv, and Lw are commonly connected at a neutral point n. The rotor 381 coupled to the propeller fan 37 has a multipolar permanent magnet. The rotor 381 rotates relative to the stator 382 by the electromagnetic force generated between the permanent magnet and the armature coils Lu, Lv, Lw, with the rotation axis as the center. In order to rotate the outdoor fan motor 38a, drive voltages Vu, Vv, Vw are output from the inverter circuit 38b to the armature coils Lu, Lv, Lw.

  The inverter circuit 38b includes upper arm insulated gate bipolar transistors Q1, Q2, and Q3 connected between the other ends of these armature coils Lu, Lv, and Lw and a high-voltage side DC power supply line 498, and these The lower arm insulated gate bipolar transistors Q4, Q5, and Q6 connected between the other end of the armature coils Lu, Lv, and Lw and the DC power supply line 499 on the low voltage side are provided as switching elements. Hereinafter, the insulated gate bipolar transistor Q1 is abbreviated as the transistor Q1, and the insulated gate bipolar transistors Q2 to Q6 are similarly described. Free-wheeling diodes D1, D2, D3, D4, D5, and D6 are connected in parallel to the transistors Q1, Q2, Q3, Q4, Q5, and Q6, respectively. Each of the free-wheeling diodes D1 to D6 is turned on when a reverse voltage is applied to the transistors Q1 to Q6 to which each of the free-wheeling diodes D1 to D6 is connected, and protects the transistors Q1 to Q6 from the reverse voltage.

  The inverter circuit 38b turns on the upper arm transistors Q1, Q2, and Q3 to turn on the armature coils Lu, Lv, and L from the high-voltage side DC power supply line 498 via the transistors Q1, Q2, and Q3. A high voltage is applied to the other end of Lw. In addition, the inverter circuit 38b turns on the lower arm transistors Q4, Q5, and Q6 to turn on the armature coils Lu, from the low-voltage side DC power supply line 499 via the transistors Q4, Q5, and Q6. A low voltage is applied to the other ends of Lv and Lw.

(4-2) Control of the inverter circuit of the outdoor fan motor unit The peripheral circuit 74 for controlling the outdoor fan motor unit 38 includes a gate control voltage generation unit 741, a PWM (Pulse-Width Modulation) control unit 742, and position detection. 743, rotation speed estimation unit 744, steady state determination unit 745, overvoltage protection unit 746, and overcurrent protection unit 747 are included.

[Gate control voltage generator]
As shown in FIG. 6, the gate control voltage generator 741 outputs six gate control voltages Gu, Gv, Gw, Gx, Gy, Gz for controlling on / off of the transistors Q1 to Q6 of the inverter circuit 38b. To do. The drive voltages Vu, Vv, Vw having the modulation rate determined by the PWM control unit 742 are based on the rotor position based on the gate control voltages Gu, Gv, Gw, Gx, Gy, Gz output from the gate control voltage generation unit 741. It is output from the inverter circuit 38b to the outdoor fan motor 38a at the timing.

[PWM control unit]
The PWM control unit 742 determines the modulation factors of the drive voltages Vu, Vv, Vw applied to the armature coils Lu, Lv, Lw based on the rotation speed of the outdoor fan motor 38a. Then, the PWM control unit 742 outputs a PWM voltage corresponding to this modulation factor to the gate control voltage generation unit 741 according to the energization timing to the armature coils Lu, Lv, Lw based on the position of the rotor 381.

(Position detector)
The position detection unit 743 is connected to the U-phase, V-phase, and W-phase armature coils Lu, Lv, and Lw, and generates rotors from induced voltages generated in the armature coils Lu, Lv, and Lw when the rotor 381 is rotating. The rotational position of 381 is detected. The position detection unit 743 outputs a position signal corresponding to the detected rotation position of the rotor 381 to the PWM control unit 742 and the rotation speed estimation unit 744.

(Rotation speed estimation unit)
The rotation speed estimation unit 744 estimates the rotation speed of the outdoor fan motor 38 a from the output signal of the position detection unit 743. The estimation of the number of rotations can be performed, for example, by counting the output signal of the position detection unit 743 for a certain time. Alternatively, the rotational speed can be estimated by measuring the period of the output signal of the position detector 743. The estimated rotation speed is output from rotation speed estimation section 744 to PWM control section 742 and steady state determination section 745.

[Steady state determination unit]
The steady state determination unit 745 determines whether or not the steady state is based on the actual rotation number of the outdoor fan motor 38a estimated by the rotation number estimation unit 744, for example. The control device 50 of the air conditioner 10 determines the target rotational speed of the outdoor fan motor 38a in accordance with a given air condition request or the environment of the air conditioner 10. The control device 50 outputs the target rotational speed to the outdoor control unit 70 as a command value. This command value is given to the steady state determination unit 745 in the peripheral circuit 74 of the outdoor control unit 70, and the steady state determination unit 745 determines that the steady state has been reached when the actual rotational speed reaches this command value. It is determined that the engine is in a starting state until reaching. If the driving of the outdoor fan motor 38a in the steady state is stopped, the steady state determination unit 745 determines that it is in the start state until it is reset and reaches the command value next time. Note that the steady state determination unit 745 determines that the engine is in the starting state even when the actual rotation number cannot be estimated by the rotation number estimation unit 744.

[Overvoltage protection section]
The overvoltage protection unit 746 adjusts the voltage across the smoothing capacitor 496 based on the voltage detected by the voltage detection unit 81 so as not to exceed the rated voltage of each of the transistors Q1 to Q6 of the inverter circuit 38b.

  The overvoltage protection unit 746 obtains a determination result as to whether or not it is in a steady state from the steady state determination unit 745. In the steady state, the overvoltage is determined using the first threshold voltage, and in the starting state, the overvoltage is determined using the second threshold voltage that is larger than the first threshold voltage. I do. In the steady state, when the voltage value detected by the voltage detection unit 81 exceeds the first threshold voltage, the overvoltage protection unit 746 instructs the gate control voltage generation unit 741 to stop driving the inverter circuit 38b. And a signal instructing the discharge unit 497 to discharge the smoothing capacitor 496. In the start state, when the voltage value detected by the voltage detection unit 81 exceeds the second threshold voltage, the gate control voltage generation unit 741 and the discharge unit generate a signal similar to that when the voltage value exceeds the first threshold voltage in the steady state. Output to 497.

[Overcurrent protection section]
The overcurrent protection unit 747 adjusts the current flowing through the outdoor fan motor 38a based on the current detected by the current detection unit 82 so as not to exceed the rated current of the transistors Q1 to Q6 of the inverter circuit 38b.

  The overcurrent protection unit 747 obtains a determination result as to whether or not the steady state determination unit 745 is in a steady state. Then, in the steady state, the overcurrent is determined using the first threshold current, and in the starting state, the overcurrent is determined using the second threshold current larger than the first threshold current. Set up. In the steady state, when the current value detected by the current detection unit 82 exceeds the first threshold current, the overcurrent protection unit 747 instructs the gate control voltage generation unit 741 to stop driving the inverter circuit 38b. Output a signal. In the start state, when the current value detected by the current detection unit 82 exceeds the second threshold current, the overcurrent protection unit 747 instructs the gate control voltage generation unit 741 to stop driving the inverter circuit 38b. Output a signal.

(4-3) Outdoor Fan Motor Unit Abnormality Detection and Control during Abnormality Abnormality detection and abnormal-time control related to overvoltage in DC power supply lines 498 and 499 that supply DC power to outdoor fan motor 38a and overcurrent of outdoor fan motor 38a This will be described with reference to FIGS.

  Conventionally, abnormality detection and control during abnormality of the air conditioner when these overvoltages and overcurrents occur are performed according to the same sequence without distinguishing between the steady state and the starting state of the outdoor fan motor 38a. It was. However, in the air conditioner 10 according to the present embodiment, these abnormality detection and abnormality control are performed along the first sequence (step S10) and the second sequence (step S20) that are different from each other in the steady state and the start state. Each is done.

  An outline of abnormality detection and control during abnormality relating to overvoltage and overcurrent of the air-conditioning apparatus 10 will be described using the flowchart of FIG. First, in step S1, the control device 50 stands by until an instruction to start the outdoor fan motor 38a is given. When there is a start instruction for the outdoor fan motor 38a, the control device 50 starts the outdoor fan motor 38a and starts measuring time using the timer 73.

  In step S <b> 2, the rotation speed estimation unit 744 estimates the rotation speed. Progressing to step S3 following step S2, the steady state determination unit 745 selects motor activation control corresponding to the rotational speed based on the actual rotational speed of the outdoor fan motor 38a, and starts the motor. Immediately after the start-up, since the actual rotational speed has not reached the command value, it is determined that the engine has been started, and the process proceeds to step S20 (second sequence).

  In step S20 (second sequence), the control device 50 performs abnormality detection under the second abnormality detection condition (step S20a). The second abnormality detection condition is different from the first abnormality detection condition. Here, the second abnormality detection condition is that the detection voltage of the voltage detection unit 81 exceeds the second threshold voltage or the detection current of the current detection unit 82 exceeds the second threshold current. On the other hand, in the abnormality detection performed in the first sequence, the first abnormality detection condition is that the detection voltage of the voltage detection unit 81 exceeds the first threshold voltage or the detection current of the current detection unit 82 exceeds the first threshold current. It has become. Therefore, since the second threshold voltage is larger than the first threshold voltage and the second threshold current is larger than the first threshold current, the second abnormality detection condition is more relaxed than the first abnormality detection condition. . The second abnormality detection condition is more relaxed than the first abnormality detection condition. When the outdoor fan motor 38a is controlled without the rotor position sensor, an external force is applied to the propeller fan 37 to cause an overcurrent state or an overvoltage. This is because there is a high possibility that a state will occur.

When an overvoltage or overcurrent is detected in the start state, it is estimated that an overvoltage or overcurrent has occurred due to an external force, and the outdoor fan motor 38a is started. That is, if an overvoltage or overcurrent occurs due to the external force acting on the propeller fan 37, it is not a failure of the outdoor fan motor 38a, and the operation may be continued under relaxed conditions. By using the relaxed second abnormality detection condition, the number of times the drive of the outdoor fan motor 38a is stopped is reduced, and the outdoor fan motor 38a can be started smoothly. However, since there is a possibility of failure of the outdoor fan motor 38a, when the first threshold voltage or the first threshold current is exceeded, the abnormality detection interval may be set to be short.

  If no abnormality is detected in step S20a, it is determined whether or not the second sequence (step S20) is shifted to the first sequence (steps S5, S6, and S7). In steps S5 and S6, the same processing as in steps S2 and S3 described above is performed, and if the actual rotational speed of the outdoor fan motor 38a has reached the command value, it is determined that it is in a steady state and the process proceeds to step S10 (first sequence). Migrated. If the actual rotational speed has not yet reached the command value, it is determined in step S7 whether or not a motor stop instruction has been issued. If there is a motor stop instruction, the process proceeds to step S8, the outdoor control unit 70 stops the outdoor fan motor 38a, and the process ends. If there is no motor stop instruction, the process returns to step S20, and the process is executed along the second sequence.

  When an abnormality is detected in step S20a, second abnormality control is performed (step S20b). The second abnormality control will be described in detail later, but control different from the first abnormality control (step S10b) is performed. The biggest difference between the first abnormality control and the second abnormality control is that the conditions for stopping the operation of the refrigerant circuit 14 are different. In the first abnormality control, when an abnormality is detected in step S10a, the driving of the outdoor fan motor 38a is stopped and the operation of the refrigerant circuit 14 is stopped. On the other hand, in the second abnormality control, when an abnormality is detected in step S20a, the driving of the outdoor fan motor 38a is stopped, but the operation of the refrigerant circuit 14 is not stopped only by detecting the abnormality in step S20a. On the other hand, since it is estimated that the outdoor fan motor 38a is rotating at a high speed from the occurrence of overvoltage or overcurrent, the driving of the outdoor fan motor 38a is stopped. At this time, even if the outdoor fan motor 38a is not driven, it is determined that the airflow necessary for heat exchange of the refrigerant circuit 14 passes through the propeller fan 37 and is supplied to the outdoor heat exchanger 33. In the starting state, the operation of the refrigerant circuit 14 is continued. And in this 2nd sequence, while the operation of the refrigerant circuit 14 is continued, detection of the occurrence of the failure of the refrigerant circuit 14 by another means is attempted. Specific examples of other means include, for example, a method of predicting the state not only based on whether the refrigerant pressure is higher than a predetermined value but also by changing the pressure value. It is preferable that the detection of the occurrence of the failure by the means is performed by strengthening the monitoring of the outdoor fan motor 38a, the refrigerant circuit 14 or their surroundings.

  If it is determined in step S20b that the operation of the refrigerant circuit 14 is stopped as well as the outdoor fan motor 38a as a result of performing the second abnormality control, the operation of the refrigerant circuit 14 is also stopped and the processing is ended. Is done. On the other hand, when the second abnormality control is performed and no abnormality is detected under the second abnormality detection condition, the process proceeds from step S20b to step S20a to step S5, and the outdoor fan motor 38a is continuously started.

  The process proceeds from step S3, S6 to step S10 (first sequence), and if an abnormality is detected in the first abnormality detection condition in step S10a, the process proceeds to step S10b and the first abnormality control is performed. When the first abnormality control is performed in step S10b, the driving of the outdoor fan motor 38a and the operation of the refrigerant circuit 14 are stopped and the processing is ended.

If no abnormality is detected in the first abnormality detection condition in step S10a, the process proceeds to step S4, where it is confirmed whether there is an instruction to stop the motor. If there is no instruction to stop the motor, the process returns to step S10a, and the determinations in steps S10a and S4 are repeated until an instruction to stop the motor is given. If there is an instruction to stop the motor, the driving of the outdoor fan motor 38a is stopped (step S8), and the process ends.

  In the above description, the selection of the start control and the determination of whether or not it is in a steady state are performed using only the rotation speed of the motor. However, the fan is particularly affected by an external force such as an outdoor unit of an air conditioner. In applications where the motor rotates, the motor can be driven more stably by taking the rotational direction into consideration.

(4-4) First Sequence Next, details of the first sequence will be described with reference to FIG. Step S10a includes step S11 for detecting overvoltage and overcurrent, and step S12 for determining whether or not abnormality is detected. In step S <b> 11, overvoltage is detected by the voltage detector 81, and overcurrent is detected by the current detector 82. Since the signal indicating the steady state is supplied from the steady state determination unit 745 to the overvoltage protection unit 746 and the overcurrent protection unit 747, the voltage detection unit 81 and the current detection unit 82 obtain the first threshold voltage and the first threshold current. Using this, abnormality detection is performed. In step S12, it is determined whether or not an overvoltage is detected by the voltage detector 81. Further, it is determined whether or not an overcurrent is detected by the current detection unit 82.

  If no abnormality is detected in step S12, the controller 50 determines whether or not there is an instruction to stop the outdoor fan motor 38a (step S4). If there is an instruction to stop, the control proceeds to step S8, and the outdoor fan motor 70 controls the outdoor fan motor. The drive of 38a is stopped and a process is complete | finished.

  If an abnormality is detected in step S12, the process proceeds to step S10b for performing the first abnormality control. Step S10b includes step S13 for controlling the outdoor fan motor 38a, step S14 for controlling the refrigerant circuit 14, and step S15 for issuing an abnormality. In step S13, the overvoltage protection unit 746 or the overcurrent protection unit 747 outputs a signal that instructs the gate control voltage generation unit 741 to stop the outdoor fan motor 38a. When an overvoltage is detected, a signal instructing discharge of the discharge unit 497 is output from the overvoltage protection unit 746 to the discharge unit 497. If abnormality is detected, a signal indicating abnormality detection is output from the overvoltage protection unit 746 and the overcurrent protection unit 747 to the CPU 71 of the outdoor control unit 70 at the same time.

  Next, the process proceeds to step S14, and the CPU 71 that has received a signal indicating abnormality detection also receives a signal indicating that it is in a steady state from the steady state determination unit 745, so the refrigerant circuit 14 must be stopped. It is judged. A signal for stopping the operation of the refrigerant circuit 14 is output to the peripheral circuit 75 from the CPU 71 in which such determination has been made. Thereby, the inverter circuit 40b is stopped by the peripheral circuit 75, the compressor motor 40a is stopped, and the operation of the refrigerant circuit 14 is stopped. In step S15, the CPU 71 outputs a signal instructing the indoor control unit 60 to display an abnormality on the display unit 28 to notify the user.

(4-5) Second Sequence Next, details of the first sequence will be described with reference to FIG. Step S20a includes step S21 for detecting overvoltage and overcurrent, and step S22 for determining the presence or absence of abnormality detection. In step S21, the voltage detector 81 detects an overvoltage, and the current detector 82 detects an overcurrent. Since a signal indicating the starting state is given from the steady state determination unit 745 to the overvoltage protection unit 746 and the overcurrent protection unit 747, the voltage detection unit 81 and the current detection unit 82 obtain the second threshold voltage and the second threshold current. Using this, abnormality detection is performed. In step S22, it is determined whether or not an overvoltage is detected by the voltage detector 81. Further, it is determined whether or not an overcurrent is detected by the current detection unit 82.

  If no abnormality is detected in step S12, the processing from step S5 to step S7 described above is performed.

  If an abnormality is detected in step S22, the process proceeds to step S20b for performing the second abnormality control. Step S20b includes steps S23 to S34. In step S23, the overvoltage protection unit 746 or the overcurrent protection unit 747 outputs a signal that instructs the gate control voltage generation unit 741 to stop the outdoor fan motor 38a. When an overvoltage is detected, a signal instructing discharge of the discharge unit 497 is output from the overvoltage protection unit 746 to the discharge unit 497. If abnormality is detected, a signal indicating abnormality detection is output from the overvoltage protection unit 746 or the overcurrent protection unit 747 to the CPU 71 of the outdoor control unit 70.

  Next, the process proceeds to step S24, and the CPU 71 that has received a signal indicating abnormality detection has also received a signal indicating that the engine is in a starting state from the steady state determination unit 745, so that the refrigerant circuit 14 still needs to be stopped. It is judged that there is no. At the same time, the CPU 71 determines that the monitoring condition of the refrigerant circuit 14 needs to be changed. Thereby, in the outdoor control unit 70, the monitoring condition of the refrigerant circuit 14 is changed. Specifically, the threshold value used for determining whether or not to stop the refrigerant circuit 14 in the subsequent step S26 is changed to a threshold pressure Pr2 that is lower than the abnormal high pressure Pr1 that causes the refrigerant circuit 14 to stop urgently.

  In the next step S25, it is determined whether or not a first predetermined time has elapsed since the driving of the outdoor fan motor 38a was stopped. This determination is made by the CPU 71 using the timer 73, for example. Therefore, for example, the time when the outdoor fan motor 38a is stopped is written in the memory 72 by the CPU 71, for example. The elapsed time from the time stored in the memory 72 to the time indicated by the timer 73 is compared with the first predetermined time, and the elapse of the first predetermined time since the outdoor fan motor 38a is stopped is determined.

  If the first predetermined time has elapsed since the stop of the outdoor fan motor 38a, there is a possibility that a malfunction may be caused by the extension of the stop period of the outdoor fan motor 38a, resulting in an abnormal stop over and over. And the process of step S29 is performed. In step S28, since the CPU 71 receives a signal indicating that the engine is in the starting state from the steady state determination unit 745, the stop of the refrigerant circuit 14 is invalidated as it is. Therefore, in the CPU 71, the stop invalidation of the refrigerant circuit 14 in the start state is canceled when the first predetermined time elapses, and the refrigerant circuit 14 can be stopped. A signal for stopping the operation of the refrigerant circuit 14 is output to the peripheral circuit 75 from the CPU 71 in which the cancellation of the stop invalidation is performed. Thereby, the inverter circuit 40b is stopped by the peripheral circuit 75, the compressor motor 40a is stopped, and the operation of the refrigerant circuit 14 is stopped. In step S29, a signal instructing the indoor control unit 60 to display an abnormality on the display unit 28 is output from the CPU 71, and an abnormality is issued. Then, the cooling operation or heating operation of the air conditioner 10 is stopped. Note that the display content of the abnormality in step S29 is preferably different from the display content of the abnormality in step S15 in order to inform the user of the cause of the stop.

If it is determined in step S25 that the first predetermined time has not elapsed, the process proceeds to step S26, and it is determined whether or not a high pressure abnormality has occurred within the second predetermined time after the outdoor fan motor 38a is stopped. . The high pressure abnormality is determined by comparing the threshold pressure Pr2 with the pressure detected by the discharge side pressure sensor 47 in the CPU 71. The second occurrence of high pressure abnormality
The CPU 71 determines whether or not it is within the predetermined time by comparing the elapsed time from the stop time of the outdoor fan motor 38a stored in the memory 72 to the time indicated by the timer 73 with the second predetermined time. Done.

  In step S26, if a high pressure abnormality is not detected within the second predetermined time, the process proceeds to step S30. If a high pressure abnormality is detected within the second predetermined time, the process proceeds to the next step S27. In the next step S27, the CPU 71 determines whether or not the number of times that the high-pressure abnormality has occurred since the outdoor fan motor 38a has stopped has reached a predetermined number. The number of times that the high voltage abnormality has occurred is stored in the memory 72 by the CPU 71.

  The fact that the number of occurrences of the high voltage abnormality reaches the predetermined number means that the cause of the overvoltage or overcurrent is not that the torque is generated in the propeller fan 37 due to the external airflow, but is likely due to a failure of the control device 50 or the like. is doing. Therefore, when the number of occurrences of high-pressure abnormality reaches a predetermined number, the process proceeds to step S28, and the cooling operation or heating operation of the air conditioner 10 is stopped by performing the above-described processing in step S28 and subsequent steps. If the number of occurrences of the high pressure abnormality has not reached the predetermined number, the process proceeds to step S30.

  In step S30, it is determined whether or not the high pressure abnormality has been resolved within a third predetermined time. If the high pressure abnormality continues even after the third predetermined time has elapsed, it is determined that there is a high possibility that an abnormality has occurred in the refrigerant circuit 14. Therefore, if the high pressure abnormality is not resolved within the third predetermined time, the process after step S28 is performed, and the cooling operation or the heating operation of the air conditioner 10 is stopped.

  If it is determined in step S30 that the high voltage abnormality has been resolved within the third predetermined time, abnormality detection for overvoltage or overcurrent is performed in steps S31 and S32. The processing in step S31 and step S32 is a determination as to whether or not the overvoltage or overcurrent has been eliminated, and the same processing as in steps S21 and S22 described above is performed. And when abnormality is detected in step S32, it returns to step S26 and the process after step S26 is repeated. On the other hand, if no abnormality is detected in step S32, the process proceeds to step S33, and the outdoor fan motor 38a is activated. After the outdoor fan motor 38a is started, the monitoring condition of the refrigerant circuit 14 is initialized (step S34), and the process returns to step S21. Here, the initialization of the monitoring condition of the refrigerant circuit 14 is a condition that is severer than usual, that is, a case where a high-pressure abnormality of the refrigerant circuit 14 is determined based on the threshold pressure Pr2, and a high-pressure abnormality caused by a normal abnormal high-pressure pressure Pr1. Return to monitoring.

(5) Features (5-1)
As described above, with respect to the inverter circuit 38b (inverter) of the outdoor fan motor unit 38, when the voltage value detected by the voltage detection unit 81 (detection unit) exceeds the threshold voltage, an overvoltage is detected by the voltage detection unit 81. It is determined that it has been performed (steps S12 and S22). Further, when the current value detected by the current detector 82 (detector) exceeds the threshold current, it is determined that an overcurrent has been detected by the current detector 82 (steps S12 and S22).

In this embodiment, the above-described abnormality detection determination is different between when the steady state determination unit 745 determines that it is in a steady state and when it determines that it is in a start state. In the steady state, abnormality detection is performed along the first sequence (step S10). At this time, the threshold voltage and threshold current used in the overvoltage protection unit 746 and the overcurrent protection unit 747 are the first threshold voltage and the first threshold value. Current (first detection reference). On the other hand, in the starting state, abnormality detection is performed along the second sequence (step S20). At this time, the threshold voltage and threshold current used in the overvoltage protection unit 746 and the overcurrent protection unit 747 are the second threshold voltage and the second threshold voltage. 2 threshold current (second detection reference). In this way, switching the threshold voltage and threshold current can be realized with a simple circuit configuration such as switching the resistance, capacitance, etc. of the detection circuit, so there is no need to provide an expensive additional circuit.

  The second threshold voltage used in the starting state has a higher value than the first threshold voltage used in the steady state, and the second threshold current has a higher value than the first threshold current. Therefore, when a voltage between the first threshold voltage and the second threshold voltage or a current between the first threshold current and the second threshold current is detected, the control at the time of abnormality is started in the first sequence, but in the second sequence, Since the control at the time of abnormality is not started, it becomes possible that the control at the time of abnormality is not performed in the second sequence even if the condition for performing the control at the time of abnormality is satisfied in the first sequence. For example, an overvoltage and an overcurrent that are likely to be generated in the propeller fan 37 due to an external force caused by an external airflow blown around the outdoor unit 30 are less likely to be influenced in the starting state. In this way, it is possible to appropriately deal with overvoltage and overcurrent that are more likely to occur in the starting state than in the steady state due to causes other than failure, and smooth starting can be performed.

  In this embodiment, the second threshold voltage and the second threshold current are higher than the first threshold voltage and the first threshold current in order to relax the second detection standard as compared to the first detection standard. However, the present invention is not limited to such a form. Even when the same threshold voltage or threshold current is used for the first detection reference and the second detection reference, there are cases in which it can be alleviated by adding other conditions to the second detection reference. For example, in the second detection criterion, in addition to exceeding the threshold voltage or threshold current, the condition is added on condition that the temperature of the refrigerant detected at a predetermined location of the refrigerant circuit 14 exceeds a predetermined value. By doing so, even when an abnormality is detected with the first detection criterion, an abnormality may not be detected with the second detection criterion, and the criteria can be relaxed. In addition, for example, reducing the number of measurements used in the second detection criterion rather than the number of measurements within a predetermined time used in the first detection criterion also reduces the criteria.

  Further, in this embodiment, the control at the time of abnormality when abnormality is detected is different between the first sequence and the second sequence. In the first abnormality control (step S10b) of the first sequence, when abnormality is detected, the driving of the outdoor fan motor 38a and the operation of the refrigerant circuit 14 are stopped based only on the detection of abnormality (step S12). . On the other hand, in the second abnormality control (step S20b) of the second sequence, the operation of the refrigerant circuit 14 is not stopped only by the determination of abnormality detection (step S22). In the second sequence, it is determined whether or not to stop the operation of the refrigerant circuit 14 in consideration of the determination results of steps S25, S26, S27 and step S30. Thereby, the refrigerant circuit 14 can be continuously operated in response to a start state in which the demand for air volume is relatively small. As a result, when the abnormality of the outdoor fan motor 38a is detected and the operation of the refrigerant circuit 14 (operation of the compressor) is immediately stopped, the start-up of the air conditioning can be accelerated or the deterioration of the air conditioning function can be prevented. it can.

(5-2)
Since the outdoor fan motor 38a of the above embodiment is controlled by the rotor position sensorless, particularly when the fan is started from a state where the fan is rotated by an external force, the start state until the stable rotor position sensorless operation is started. In, abnormal detection increases. Therefore, when the second sequence is used for the outdoor fan motor 38a in which the rotor position sensorless control is performed, it is often possible to avoid stopping the useless outdoor fan motor 38a and thus stopping the air conditioner.

(6) Modification (6-1)
In the above-described embodiment, the air conditioner 10 in which the brushless DC motor in which the rotor position sensorless control is performed is provided in the outdoor unit 30 is described as an example of the driving device having a motor. When a brushless DC motor that performs rotor position sensorless control is installed in the indoor fan motor unit 23, the present invention can also be applied to the indoor fan motor unit 23. Further, the drive device having a motor is not limited to the air conditioner 10 as in the above-described embodiment, and may be applied to other drive devices having a motor such as a heat pump air conditioner power supply unit having a built-in motor. Can do.

(6-2)
In the above embodiment, even when the abnormality detection is performed in the voltage detection unit 81 or the current detection unit 82 and the first abnormality control is performed in the first sequence, the second abnormality control is not performed in the second sequence. In order to achieve this, a case has been described in which the threshold for detecting an overvoltage or overcurrent is made different between the first sequence and the second sequence. However, in order to create a situation where the second sequence control is not performed in the second sequence even when the first sequence control is performed in the first sequence, another configuration can be used.

  It is also possible to remove step S28 in the second sequence (step S20) shown in FIG. That is, regarding the operation of the refrigerant circuit 14, it is possible to adopt a configuration in which the abnormal time control is not performed. Such a configuration can be applied to, for example, an air conditioner of a type having a small air volume in the start state. As a result, a decrease in the air conditioning function can be prevented as compared with the case where the operation of the refrigerant circuit 14 (operation of the compressor) is stopped immediately upon detection of an abnormality in the outdoor fan motor 38a. Alternatively, the second sequence (step S20) shown in FIG. 7 may be removed, and after step S3, the processing after step S5 may be performed. In the case of such a configuration, if there is no motor stop instruction in step S7, the process returns to step S3.

(6-3)
In the above embodiment, in step S26, the discharge side pressure detected by the discharge side pressure sensor 47 is used to detect an abnormality in the refrigerant circuit 14. However, other pressure sensors 46 and temperature sensors 24 to 26, 42 to are used. Other detection means and detection devices such as 45 may be used.

(6-4)
In the above embodiment, the steady state determination unit 745 determines the steady state based on the number of rotations of the outdoor fan motor 38a. However, the steady state can be determined by other methods. For example, in the case of a brushless DC motor in which the rotor position sensorless control of the type that is forcibly driven at an arbitrary frequency and voltage in the start state, such a state of forcible drive is started in the CPU 71, for example. The state may be determined.

  Further, in the case of a brushless DC motor in which position sensorless control of a type that performs rotor position fixing depending on direct current energization or the like is performed, the period of such rotor position fixing or the end of the rotor position fixing until a predetermined time elapses. For example, the CPU 71 may determine the state as a start state.

(6-5)
In the above embodiment, in the second abnormality control of the second sequence (step S20), unlike the abnormal high pressure Pr1 (first condition) for monitoring the high pressure abnormality of the refrigerant circuit 14 in the first sequence (step S10), The refrigerant circuit 14 is monitored using a threshold pressure Pr2 (second condition) that is stricter (lower) than the first condition. Then, even if the abnormal high pressure Pr1 has not been reached (first condition), it is determined that an abnormality has occurred in the refrigerant circuit 14 when the threshold pressure Pr2 (second condition) is satisfied, even if the first condition is not satisfied. (Step S25). As described above, in order to strengthen monitoring of the refrigerant circuit 14 when abnormality is detected in the second sequence,
Even when the abnormality control is not applied to the operation of the refrigerant circuit 14 in the sequence, the abnormality of the operation of the refrigerant circuit can be detected early.

  However, the method of strengthening the monitoring of the refrigerant circuit 14 in the second sequence is not limited to the above method. For example, the hatched area in FIG. 10 is a measured value of the discharge-side pressure sensor 47 that does not appear during normal compressor operation. As a monitoring condition in changing the monitoring condition of the second sequence (step S24), a case where the pressure on the discharge side of the compressor 31 is in such a shaded region can be set as a judgment condition for high pressure abnormality. . In addition to the change of the threshold pressure Pr2, by adding a determination as to whether or not the region is in such a hatched region, for example, even if the discharge side pressure of the compressor 31 does not increase due to a failure of the control device 50, a high pressure abnormality The situation that can be determined as a failure is added. In FIG. 10, the region following the start state of the outdoor fan motor 38a is set to the steady state or the start state when the period until the steady state is prolonged or after the outdoor fan motor 38a reaches the steady state. This is to include the case of stopping and returning to the starting state.

(6-6)
In the above-described embodiment, the case where the abnormality detection of the first sequence (step S10a) and the abnormality detection of the second sequence (step S20a) are different from each other has been described. However, the abnormality detection is made the same, and the abnormality control (steps S10b and S20b) is performed. ) Only can be different. That is, the same threshold value may be used in step S11 and step S12. Even in the second sequence configured in this way, unlike the first sequence, it is possible to perform processing in which the refrigerant circuit 14 is not stopped only by abnormality detection. Therefore, even if abnormality is detected in the second sequence, the operation of the refrigerant circuit 14 can be continued, and the temperature adjustment of the cooling operation or the heating operation can be accelerated.

(6-7)
In the above-described embodiment, the case where the first-sequence abnormality control (step S10b) and the second-sequence abnormality control (step S20b) are different from each other has been described. , S20a) may be different. Even in this case, as described above, even when the abnormal state control is performed in the first sequence, the abnormal control is not performed in the second sequence, and therefore the torque is generated by the external fan 38a in the starting state due to the external force. It can correspond to.

(6-8)
In the above embodiment, both the overvoltage and the overcurrent can be detected, and it is determined that an abnormality has been detected if either the overvoltage or the overcurrent has occurred. Also good. It can also be configured to determine that an abnormality has been detected when both overvoltage and overcurrent are detected.

  Further, it is possible to detect a step-out and to determine that an abnormality has been detected if a step-out has occurred. Furthermore, it is possible to perform an abnormality detection by appropriately combining overvoltage, overcurrent, and step-out detection.

  The step-out determination is made, for example, by determining that the difference between the motor current calculated (estimated) from the motor drive system model and the actually measured current in the rotor position sensorless control is larger than a predetermined threshold. This can be done by making a judgment.

(6-9)
In the above-described embodiment, an example of stopping the operation of the refrigerant circuit by stopping the operation of the compressor of the refrigerant circuit will be described as an example of performing the apparatus operation other than the motor in the abnormality control of the air conditioner 10 (drive device). did. However, the device operation other than the motor performed in the abnormal control is not limited to stopping the operation of the compressor, and may be another device operation such as changing the opening degree of the motor-operated valve 34, for example.

(6-10)
In the above-described embodiment, the case where the abnormal report is issued by the display unit 28 has been described, but the abnormal report is not limited to the display. For example, you may alert | report by other alerting | reporting means, such as a warning sound.

(6-11)
In the above embodiment, the detection value is changed by switching the detection circuit configuration, but the same circuit / detection value may be used and the threshold value for determining an abnormality may be changed by software.

DESCRIPTION OF SYMBOLS 10 Air conditioning apparatus 14 Refrigerant circuit 20 Indoor unit 30 Outdoor unit 31 Compressor 37 Propeller fan 38 Outdoor fan motor part 38a Outdoor fan motor 38b Inverter circuit 50 Control apparatus 70 Outdoor control part 81 Voltage detection part 82 Current detection part

JP 2003-148788 A

Claims (16)

A control device (50) for a drive device (10) including a motor (38a) to which drive power is supplied by an inverter (38b),
A detector (81, 82) for detecting an abnormality by detecting an abnormality of at least one of the inverter and the motor;
The abnormality detection by the detection unit and the control at the time of abnormality of the drive device corresponding thereto are performed in accordance with the first sequence (S10) in the steady state of the motor, and the first in the starting state before the steady state. A control unit (70) for performing along a second sequence (S20) different from the sequence;
A control device comprising: The control unit does not start the abnormal time control in the second sequence even when starting the abnormal time control in the first sequence by the abnormality detection in the detection unit,
The control device according to claim 1. The abnormality detected by the detection unit is at least one of an overvoltage of the inverter, an overcurrent of the motor, and a step-out of the motor.
The control device according to claim 1 or 2. When the control unit exceeds the threshold voltage for determining the overvoltage, the threshold current for determining the overcurrent of the motor, and the threshold for determining step-out, the control unit performs the abnormal time control in the steady state. However, the abnormal control is not performed in the starting state.
The control device according to claim 3. In the first sequence, the control unit uses the second detection criterion that is more relaxed than the first detection criterion for the detection unit to perform the abnormality detection in the first sequence. Even in the case of starting the abnormal control, the abnormal control is not started in the second sequence.
The control device according to any one of claims 2 to 4. Even if the control unit performs the abnormal time control in the first sequence by stopping or invalidating the abnormality detection in the detection unit in the second sequence, the control unit performs the abnormality control in the second sequence. Do not perform control when abnormal,
The control device according to any one of claims 2 to 5. The control unit stops the driving of the motor in any of the first sequence and the second sequence if the rotational speed of the motor exceeds a predetermined value.
The control device according to any one of claims 1 to 6. The controller performs rotor position sensorless control of the motor, and determines that the motor has shifted to a stable rotor position sensorless operation as a steady state.
The control device according to any one of claims 1 to 7. The controller determines that the steady state has been reached when the rotational speed of the motor has reached a command value;
The control device according to any one of claims 1 to 8. Fan (37),
A fan motor (38a) is supplied with driving power by an inverter and drives the fan.
)When,
A detection unit (81, 82) that detects an abnormality by detecting an abnormality in at least one of the inverter and the fan motor, and the abnormality detection in the detection unit and the control at the time of abnormality of the device according to the abnormality A control device (50) having a control unit (70) that performs along a first sequence in a steady state of the fan motor and performs along a second sequence different from the first sequence in a starting state before the steady state; ,
A heat pump device. The abnormality detected by the detection unit is at least one of an overvoltage of the inverter, an overcurrent of the fan motor, and a step-out of the fan motor.
The heat pump apparatus according to claim 10. Further comprising a refrigerant circuit (14) for circulating a refrigerant to exchange heat with an air flow through the fan;
The control unit does not start the abnormal time control for the operation of the refrigerant circuit in the second sequence even when the abnormal time control is started for the operation of the refrigerant circuit in the first sequence. The heat pump apparatus according to claim 11. In the second sequence, the control unit monitors the refrigerant circuit using a second condition that is stricter than the first condition, unlike the first condition in which the refrigerant circuit is monitored in the first sequence. Determining that an abnormality has occurred in the refrigerant circuit when the second condition is satisfied even if the first condition is not satisfied;
The heat pump apparatus according to claim 12. When the controller determines that the second condition is satisfied and an abnormality has occurred, the controller performs an abnormality control of the operation of the refrigerant circuit.
The heat pump apparatus according to claim 13.   The heat pump according to claim 13 or 14, wherein the control unit issues an abnormality when the number of times that the second condition is satisfied and an abnormality has occurred exceeds a predetermined number. apparatus. The fan and the fan motor are installed in an outdoor unit (30),
The heat pump device according to any one of claims 10 to 15.

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