JP3594358B2 - Air conditioner - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to an air conditioner, and more particularly to an air conditioner provided with a control unit having a failure diagnosis function for various sensors that detect an operation state.
[0002]
[Prior art]
Conventionally, in an air conditioner having an indoor unit and an outdoor unit, a controller and a sensor unit are provided in the outdoor unit, a temperature sensor installed in each pipe in the outdoor unit and connected to the controller in the sensor unit, and a temperature sensor in the power supply box. There is a known type including a CT (Current Transformer) sensor installed on a power cable line (for example, any one of an R-phase line, an S-phase line, and a T-phase line) and connected to a controller.
[0003]
The CT sensor is a monitoring sensor that detects a current value flowing through a power supply line after the air conditioner enters an operation state, and enables the outdoor unit to continuously operate within a predetermined guaranteed range.
[0004]
In such an air conditioner, a method shown in FIG. 6 is known as a processing flow of a controller for detecting a failure of a sensor unit. That is, as shown in FIG. 6, in this processing procedure, immediately after the operation of the air conditioner, it is first determined whether or not the frequency of the compressor in the outdoor unit is equal to or higher than a predetermined value X (step S101). As the value X in this case, a value of about 20 to 30 Hz is used. If the compressor frequency is less than the value X in step S101 (in the case of No), the processing in this cycle is ended. If the compressor frequency is not less than the value X in step S101 (in the case of Yes), step S102 is performed. Then, it is determined whether or not the current value detected by the CT sensor is equal to or less than a predetermined value Y. As the value Y in this case, a value of about 0.4 A is used. If the CT detection current value exceeds the value Y (No) in step S102, the processing in this cycle is terminated. If the CT detection current value is equal to or less than the value Y (Yes) in step S102, The process proceeds to step S103, where it is determined that "the CT sensor is defective", and a warning display or a warning sound is issued to the outside.
[0005]
Further, instead of step S101, a process of determining whether the temperature value of a discharge temperature sensor such as a thermistor for measuring the temperature of the refrigerant discharged from the compressor in the outdoor unit is equal to or higher than a predetermined value W is also performed. Had been
[0006]
[Problems to be solved by the invention]
However, in the above-described conventional air conditioner, particularly when the outside air temperature is extremely low in winter, for example, the R value of the thermistor at 0 ° C. is as large as 180 kΩ. In some cases, the value of the discharge temperature sensor indicates a temperature that cannot occur normally, and it is determined that the sensor is defective (open defect) although the sensor is actually normal.
[0007]
In the case of a CT sensor, when the inverter operation is performed when the outside air temperature is about 0 ° C., the operation frequency is extremely low and the operation current value is low in an initial state immediately after the start of operation. For example, the operating current value at 0 ° C. during the inverter operation at 30 Hz is about 0.8 to 1.2 A. As the outside air temperature further decreases, the refrigerant pressure decreases, and the operating current of the compressor further decreases. For this reason, when the determination is made immediately after the operation of the air conditioner, depending on the configuration of the circuit for determining the value from the CT sensor, it is determined that the sensor is defective (open failure) even though the sensor is actually normal. There was sometimes.
[0008]
An object of the present invention is to provide an air conditioner that operates stably regardless of the operating environment.
[0009]
[Means for Solving the Problems]
The present invention is the air conditioning apparatus performs air conditioning control by detecting the operating state by the sensor means comprising a current detector connected to the outdoor controller installed in the electric power cable line, and a discharge temperature sensor of the compressor, the outdoor controller Determines whether the frequency of the compressor in the outdoor unit is equal to or higher than a predetermined value.If the compressor frequency is equal to or higher than the predetermined value, it determines whether the value of the discharge temperature in the discharge temperature sensor is equal to or higher than the predetermined temperature. If the value of the discharge temperature is lower than the predetermined temperature, it is determined whether or not the elapsed time from the start of the operation of the compressor is equal to or less than a predetermined time, and the elapsed time from the start of the operation of the compressor is predetermined. If the current value reaches the predetermined time, it is determined whether the current value detected by the current detector is equal to or less than a predetermined value. If the current value is equal to or less than the predetermined value, it is determined that the current detector is defective and the external Sensor failure Characterized by comprising a means out.
[0013]
[Action]
According to the first aspect of the present invention, the sensor failure detection means detects whether the sensor means is defective after the operation state of the air conditioner has entered the stable region, so that the sensor means is normal. Erroneous detection as a failure.
[0017]
【Example】
Next, a preferred embodiment of the present invention will be described with reference to the accompanying drawings.
[0018]
FIG. 1 shows an embodiment of an air conditioner according to the present invention. As shown in FIG. 1, the air conditioner 100 includes an outdoor unit 1 and an indoor unit 2.
[0019]
The outdoor unit 1 has an outdoor controller 11, a discharge temperature sensor 12, an outdoor heat exchanger temperature sensor 13, a compressor 15, and an outdoor fan 16.
[0020]
The indoor unit 2 has an indoor controller 21, an indoor temperature sensor 22, an indoor heat exchanger temperature sensor 23, a suction temperature sensor 24, an indoor fan 25, and a remote control unit 26.
[0021]
The remote control unit 26 has an operation unit 27 including operation switches and the like, and a display unit 28 including a liquid crystal display and the like.
[0022]
The discharge temperature sensor 12 is provided in a refrigerant pipe discharged from the compressor 15 and measures the temperature of the refrigerant discharged from the compressor 15.
[0023]
The CT sensor 14 is provided on a power supply line (not shown) and detects a current value flowing through the power supply line.
[0024]
The outdoor unit 1 and the indoor unit 2 are connected by a refrigerant pipe (not shown). Further, the indoor unit 2 has a built-in indoor heat exchanger (not shown) that functions as an evaporator during cooling operation and as a condenser during heating. The indoor heat exchanger temperature sensor 23 measures the temperature of the indoor heat exchanger.
[0025]
The compressor 15 in the outdoor unit 1 compresses the refrigerant. The outdoor unit 1 includes, in addition to the compressor 15, various valves (not shown), an outdoor heat exchanger (not shown) that acts as a condenser during cooling operation and acts as an evaporator during heating, and an accumulator (not shown). And the like are built in and connected by the refrigerant pipe (not shown).
[0026]
The outdoor heat exchanger temperature sensor 13 measures the temperature of the outdoor heat exchanger.
[0027]
In the above configuration, during normal cooling operation, various valves are switched for cooling, and the refrigerant radiated by the outdoor heat exchanger flows through the refrigerant pipe to the indoor heat exchanger to perform heat exchange. After the cooling air is sent out (cooling) by rotating it, it returns to the outdoor heat exchanger through the refrigerant pipe and radiates heat again.
[0028]
At the time of heating operation, various valves are switched for heating, the refrigerant absorbed by the outdoor heat exchanger flows through the refrigerant pipe to the indoor heat exchanger, and heat is exchanged by rotating the indoor fan 25. And then returns to the outdoor heat exchanger through the refrigerant pipe to absorb heat again.
[0029]
Next, a procedure for detecting a sensor failure in the air conditioner 100 of the present embodiment will be described. FIG. 2 shows a procedure of a first method for detecting a sensor failure in the air conditioner 100 described above. In this case, a timer (not shown) for the time Z for hardware or software is provided in the outdoor controller 11 shown in FIG.
[0030]
As shown in FIG. 2, first, the outdoor controller 11 determines whether or not the frequency of the compressor 15 in the outdoor unit 1 is equal to or higher than a predetermined value X (step S11). As the value X in this case, a value of about 20 to 30 Hz is used. If the compressor frequency is less than the value X (No) in step S11, the processing in this cycle is ended. If the compressor frequency is more than the value X (Yes) in step S11, step S12 is performed. Then, it is determined whether or not the elapsed time from the start of the operation of the compressor 15 is equal to or less than a predetermined time Z. As the value Z in this case, a value of about 1 to 2 minutes is used.
[0031]
If the elapsed time from the start of the operation of the compressor 15 does not reach the value Z in step S12 (No), the processing in this cycle is terminated, but the elapsed time from the start of the operation of the compressor 15 in step S12. Has reached the value Z (in the case of Yes), the process proceeds to step S13, and it is determined whether or not the current value detected by the CT sensor 14 is equal to or less than a predetermined value Y. As the value Y in this case, a value of about 0.4 A is used.
[0032]
If the CT detection current value exceeds the value Y in the step S13 (No), the processing in this cycle is terminated. If the CT detection current value is the value Y or less in the step S13 (Yes), Then, the outdoor controller 11 proceeds to step S14, determines that the CT sensor is defective, and notifies the outside with a warning display or a warning sound. This warning display is displayed on the display unit 28 of the remote control unit 26, for example. According to such a processing procedure, the sensor failure is determined after the elapse of Z minutes from the start of the operation and after the operation state of the air conditioner 100 enters the stable region, instead of the sensor failure determination immediately after the start of the operation as in the related art. Erroneous detection of a sensor failure will not occur. However, in the case of the first method, depending on the value of the timer setting time Z, the sensor failure determination may be performed before the operation state of the air conditioner 100 enters the stable region. The value needs to be set to a certain length.
[0033]
Next, a procedure of a second method for detecting a sensor failure in the air conditioner 100 of the present embodiment will be described with reference to FIG. As shown in FIG. 3, in this processing procedure, first, the outdoor controller 11 determines whether or not the frequency of the compressor 15 in the outdoor unit 1 is equal to or higher than a predetermined value X (step S21). As the value X in this case, a value of about 20 to 30 Hz is used.
[0034]
If the compressor frequency is less than the value X in the step S21 (No), the processing in this cycle is ended. If the compressor frequency is the value X or more in the step S21 (Yes), the process goes to the step S22. Then, it is determined whether or not the value of the discharge temperature in the discharge temperature sensor 12 is equal to or higher than a predetermined temperature W. As the value W in this case, for example, a value of about 50 ° C. is used. This is because, in the air conditioner, when the air conditioner is stopped, the discharge temperature is about 40 ° C. at the maximum in summer and about −10 ° C. to + 10 ° C. in winter.
[0035]
If the value of the discharge temperature of the discharge temperature sensor 12 is lower than the predetermined temperature W in step S22 (No), the process in this cycle is terminated. If the temperature is equal to or higher than the predetermined temperature W (Yes), the process proceeds to step S23, and it is determined whether the current value detected by the CT sensor 14 is equal to or lower than the predetermined value Y. As the value Y in this case, a value of about 0.4 A is used. If the CT detection current value exceeds the value Y in the step S23 (in the case of No), the process in this cycle is ended. If the CT detection current value is the value Y or less in the step S23 (in the case of Yes), Then, the outdoor controller 11 proceeds to step S24, determines that the CT sensor is defective, and notifies the outside with a warning display or a warning sound. This warning display is displayed on the display unit 28 of the remote control unit 26, for example.
[0036]
According to such a processing procedure, not only the sensor failure determination immediately after the start of operation as in the conventional case, but also the CT sensor failure is determined after the discharge temperature becomes W ° C or more and the operation state of the air conditioner 100 enters the stable region. Therefore, erroneous detection of a CT sensor failure does not occur. However, in the case of the second method, when the discharge temperature sensor 12 has an open failure, a CT sensor failure cannot be detected.
[0037]
Next, a procedure of a third method for detecting a sensor failure in the air conditioner 100 of the present embodiment will be described with reference to FIG. As shown in FIG. 4, the outdoor controller 11 determines whether the frequency of the compressor 15 in the outdoor unit 1 is equal to or higher than a predetermined value X (step S31). As the value X in this case, a value of about 20 to 30 Hz is used. If the compressor frequency is less than the value X (No) in step S31, the process in this cycle is terminated. If the compressor frequency is more than the value X (Yes) in step S31, step S32 is performed. Then, it is determined whether or not the elapsed time from the start of the operation of the compressor 15 is equal to or less than a predetermined time Z. As the value Z in this case, a value of about 1 to 2 minutes is used.
[0038]
If the elapsed time from the start of the operation of the compressor 15 does not reach the value Z in step S32 (No), the processing in this cycle is terminated, but the elapsed time from the start of the operation of the compressor 15 in step S32 Has reached the value Z (in the case of Yes), the process proceeds to step S33, and it is determined whether or not the value of the discharge temperature of the discharge temperature sensor 12 is equal to or higher than a predetermined temperature W. As the value W in this case, a value of about 50 ° C. is used.
[0039]
If the value of the discharge temperature in the discharge temperature sensor 12 is lower than the predetermined temperature W (No in Step S33), the process in this cycle is terminated. If the temperature is equal to or higher than the predetermined temperature W (Yes), the process proceeds to step S34, and it is determined whether the current value detected by the CT sensor 14 is equal to or lower than the predetermined value Y. As the value Y in this case, a value of about 0.4 A is used.
[0040]
If the CT detection current value exceeds the value Y in the step S34 (in the case of No), the processing in this cycle is ended. If the CT detection current value is the value Y or less in the step S34 (in the case of Yes), Then, the outdoor controller 11 proceeds to step S35, determines that the CT sensor is defective, and notifies the outside with a warning display or a warning sound. This warning display is displayed on the display unit 28 of the remote control unit 26, for example.
[0041]
According to such a processing procedure, the operation state of the air conditioner 100 enters the stable region after Z minutes have elapsed since the start of operation and the discharge temperature has become equal to or higher than W ° C., instead of the sensor failure determination immediately after the start of operation as in the conventional case. After that, the sensor failure is determined, so that erroneous detection of the sensor failure does not occur. That is, the third method can be said to be a method in which a logical product (AND) of the first method and the second method described above is obtained. However, in the case of the third method, as in the case of the above-described second method, when the discharge temperature sensor 12 has an open defect, a CT sensor defect cannot be detected.
[0042]
Next, a procedure of a fourth method for detecting a sensor failure in the air conditioner 100 of the present embodiment will be described with reference to FIG. As shown in FIG. 5, the outdoor controller 11 determines whether the frequency of the compressor 15 in the outdoor unit 1 is equal to or higher than a predetermined value X (step S41). As the value X in this case, a value of about 20 to 30 Hz is used.
[0043]
If the compressor frequency is less than the value X in the step S41 (No), the processing in this cycle is ended. If the compressor frequency is the value X or more in the step S41 (Yes), the step S42 is performed. Then, it is determined whether or not the value of the discharge temperature in the discharge temperature sensor 12 is equal to or higher than a predetermined temperature W. As the value W in this case, a value of about 50 ° C. is used. If the value of the discharge temperature of the discharge temperature sensor 12 is lower than the predetermined temperature W in the step S42 (No), the process proceeds to the next step S43. If the temperature is not less than the temperature W (Yes), the process jumps to step S44.
[0044]
In step S43, it is determined whether or not the elapsed time from the start of the operation of the compressor is equal to or shorter than a predetermined time Z. As the value Z in this case, a value of about 1 to 2 minutes is used. If the elapsed time from the start of operation of the compressor has not reached the value Z in step S43 (No), the processing in this cycle is terminated. If Z has been reached (in the case of Yes), the process moves to step S44.
[0045]
In step S44, it is determined whether the current value detected by the CT sensor is equal to or less than a predetermined value Y. As the value Y in this case, a value of about 0.4 A is used. When the CT detection current value exceeds the value Y in the step S44 (in the case of No), the processing in this cycle is ended. In the case where the CT detection current value is the value Y or less (in the case of Yes) in the step S44. Then, the outdoor controller 11 proceeds to step S45, determines that the CT sensor is defective, and notifies the outside with a warning display or a warning sound. This warning display is displayed on the display unit 28 of the remote control unit 26, for example.
[0046]
According to such a processing procedure, instead of the conventional sensor failure determination immediately after the start of operation, Z minutes have elapsed after the start of operation, or the discharge temperature has become equal to or higher than W ° C., and the operation state of the air conditioner 100 is in a stable region. Since the sensor failure is determined after the entry, the sensor failure is not erroneously detected. That is, the third method can be said to be a method in which a logical sum (OR) of the first method and the second method is obtained. In the case of the fourth method, there is no problem as in the above-described first to third methods, and a sensor failure of the sensor can be reliably detected.
[0047]
Although the present invention has been described based on the embodiments of the present invention, the present invention is not limited to the above embodiments.
[0048]
For example, in the first to fourth sensor failure detection methods of the above-described embodiment, the failure detection method for the CT sensor is described as an example. However, this is not limited to the CT sensor. The defect detection can be performed in the same manner for the sensor of (1).
[0049]
In the above embodiment, the elapsed time Z after the start of operation or the temperature W on the discharge side of the compressor is used to determine that the air conditioner has entered a stable operation state. Other indicators may be used.
[0050]
Further, in the above-described embodiment, an example in which the outdoor controller performs the sensor failure detection is described.This is because the outdoor controller receives information from each sensor and sends this information to the indoor controller via a line. In response to this, the indoor controller may execute sensor failure detection.
[0051]
Therefore, in the above description, the outdoor controller or the indoor controller, or the outdoor controller and the indoor controller, correspond to a sensor failure detecting unit. Each sensor such as the CT sensor 14 corresponds to sensor means. The discharge temperature sensor 12 corresponds to a temperature sensor. The hardware or software timer set in the outdoor controller 11 corresponds to a timer.
[0052]
【The invention's effect】
As described above , according to the present invention, the sensor failure detecting means detects whether or not the sensor means is defective after the operation state of the air conditioner enters the stable region, so that the sensor means is normal. There is no erroneous detection of a defect. Therefore, it is possible to provide an air conditioner that can accurately detect a sensor failure regardless of the operating environment.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of an embodiment of an air conditioner of the present invention.
FIG. 2 is a flowchart illustrating a procedure of a first method of detecting a sensor failure in the air conditioner illustrated in FIG. 1;
FIG. 3 is a flowchart illustrating a procedure of a second method of detecting a sensor failure in the air conditioner illustrated in FIG. 1;
FIG. 4 is a flowchart illustrating a procedure of a third method of detecting a sensor failure in the air conditioner illustrated in FIG. 1;
FIG. 5 is a flowchart illustrating a procedure of a fourth method of detecting a sensor failure in the air conditioner illustrated in FIG. 1;
FIG. 6 is a flowchart illustrating a procedure for detecting a sensor failure in the conventional air conditioner.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 outdoor unit 2 indoor unit 11 outdoor controller 12 discharge temperature sensor 13 outdoor heat exchanger temperature sensor 14 CT sensor 15 compressor 16 outdoor fan 21 indoor controller 22 indoor temperature sensor 23 indoor heat exchanger temperature sensor 24 suction temperature sensor 25 indoor fan 26 remote control unit 27 operation unit 28 display unit 100 air conditioner S step

Claims (1)

In an air conditioner that performs an air conditioning control by detecting an operation state by a current detector installed on a power cable line and connected to an outdoor controller, and a sensor unit including a discharge temperature sensor of a compressor ,
The outdoor controller,
It is determined whether or not the frequency of the compressor in the outdoor unit is equal to or higher than a predetermined value.If the compressor frequency is equal to or higher than a predetermined value, it is determined whether or not the discharge temperature value of the discharge temperature sensor is equal to or higher than a predetermined temperature. If the value of the discharge temperature is lower than the predetermined temperature, it is determined whether or not the elapsed time from the start of the operation of the compressor is equal to or less than a predetermined time, and the elapsed time from the start of the operation of the compressor is a predetermined time. When the current value reaches the predetermined value, it is determined whether or not the current value detected by the current detector is equal to or less than a predetermined value. When the current value is equal to or less than the predetermined value, the current detector is determined to be defective, and is notified to the outside. An air conditioner, comprising: a sensor failure detecting unit that performs detection.

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