JP2008216209A - Humidity sensor failure detecting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a humidity sensor failure detecting system which has higher reliability over a wide range of humidity conditions. <P>SOLUTION: The system includes detected result determining means (S15, S16) for determining whether the detected room humidity sensed by room humidity sensor 22 exists within normal humidity range, and normal humidity range determining means (S14, namely, S141-S148 (see Fig. 3)) for determining normal humidity range from estimated room humidity associated with both the detected room temperature sensed by a room temperature sensor in acquisition of the detected room humidity and the detected evaporator outlet side temperature sensed by evaporator outlet side temperature sensor in acquisition of the detected room humidity. If the detected room humidity is found to be beyond the normal humidity range as a result of determination by the detected result determining means, humidity sensor failure determining section for determining abnormality of the room humidity sensor 22 (that is, S20-S22 are performed) will be provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a humidity sensor abnormality detection system that detects an abnormality of a humidity sensor.

  Conventionally, as a humidity sensor abnormality detection system, for example, one described in Patent Document 1 is known. In this humidity sensor abnormality detection system, it is determined whether or not the relative humidity (detected relative humidity) detected by the humidity sensor is within a predetermined range, and if the detected relative humidity is within the predetermined range. If the humidity sensor is determined to be normal and the detected relative humidity is outside the predetermined range, the humidity sensor is determined to be abnormal.

In the following, “relative humidity” is referred to as “humidity”.
JP 2001-153438 A

  However, in the conventional humidity sensor abnormality detection system, the default value used for the abnormality detection of the humidity sensor is set from a predetermined upper limit value and lower limit value. For this reason, the detected humidity is determined to be abnormal if the detected humidity is outside the range of the default value, regardless of the amount of deviation from the actual humidity. That is, if the actual humidity is outside the predetermined range, the humidity sensor cannot be detected abnormally.

  In this case, if the range of the default value is expanded, the humidity conditions that allow the abnormality determination are expanded, but the reliability of the abnormality determination is lowered, and if the width of the default value is reduced, the reliability of the abnormality determination is improved. However, there is a problem that the humidity condition that can be judged as abnormal is reduced.

  The present invention has been made paying attention to the above problem, and an object thereof is to provide a humidity sensor abnormality detection system having high reliability in a wide range of humidity conditions.

Detection result determination means for determining whether or not the detected indoor humidity detected by the indoor humidity sensor is in a normal humidity range;
The normal humidity range is a detected indoor temperature detected by an indoor temperature sensor when the detected indoor humidity is acquired, and a detected evaporator outlet temperature detected by an evaporator outlet side temperature sensor when the detected indoor humidity is acquired. And a normal humidity range determining means for determining based on the estimated indoor humidity according to
As a result of the determination by the detection result determination means, when the detected indoor humidity does not exist in the normal humidity range, a humidity sensor abnormality determining unit is provided for determining abnormality of the indoor humidity sensor.

  In the humidity sensor abnormality detection system of the present invention, whether the indoor humidity sensor is normal or abnormal is determined based on whether the indoor humidity (indoor humidity) detected by the indoor humidity sensor by the detection result checking means is normal. Judgment is made based on whether or not it is within the range.

  By the way, as will be described later, the indoor humidity can be handled as a function of only the indoor temperature and the evaporator outlet side temperature, and therefore can be estimated from only these two temperatures.

  The normal humidity range is based on the indoor humidity estimated by the normal humidity range determining means according to the indoor temperature at the time of detecting the indoor humidity and the evaporator outlet side temperature at the same time of detecting the indoor humidity. It is determined.

  For this reason, the normal humidity range used to determine the normal humidity range used to determine whether the indoor humidity is normal or abnormal is constantly updated according to the indoor humidity at the time of detecting the indoor humidity, and approximates the actual indoor humidity. Since it is based on the estimated indoor humidity, the reliability of determination by the detection result determination means is high.

  That is, according to the present invention, a highly reliable humidity sensor abnormality detection system can be realized under a wide range of humidity conditions.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a best mode for realizing a humidity sensor abnormality detection system of the invention will be described with reference to the drawings.

First, the configuration will be described.
FIG. 1 is an overall structural diagram of the humidity sensor abnormality detection system according to the first embodiment.
This humidity sensor abnormality detection system is mounted on a vehicle and generates signals such as an air conditioner 3, a CU (air conditioning control unit) 1 having a humidity sensor abnormality determination unit, and sensors (reference numerals 21 to 28) connected thereto. Consists of systems.

  The air conditioner 3 includes an air conditioning unit 31 in which an evaporator 321 and a heater core 35 are housed. Air (introduced air) introduced into the air conditioning unit 31 is cooled through the evaporator 321, and the heater core 35 is Passed and warmed.

  The introduced air is introduced by the negative pressure inside the air conditioning unit 31 generated by driving the blower fan 34, and the inside air is introduced from the inside air inlet 311 provided in the air conditioning unit 31 and the outside air is introduced from the outside air inlet 312. The Then, the introduced air leads to a defroster duct 313 that leads to a defroster outlet (not shown) provided in the air conditioning unit 31, a face duct 314 that leads to a face outlet (not shown), and a foot outlet (not shown). It is guided to each duct of the foot duct 315 and used for indoor air conditioning.

  A switching damper 371 for adjusting the mixing ratio of the inside air and the outside air is provided in the vicinity of the opening of the inside air inlet 311 and the outside air inlet 312 so that the inside air circulation mode or the outside air circulation mode can be selected. Further, a switching damper 372 and a switching damper 373 are provided in the vicinity of the openings of the defroster duct 313, the face duct 314, and the foot duct 315, and the introduced air guided to the ducts by adjusting the positions of the switching dampers. The ratio can be adjusted. Further, an air mix damper 374 is provided on the downstream side of the evaporator 321 and on the upstream side of the heater core 35, and the ratio of the introduced air passing through the evaporator 321 and the heater core 35 is adjusted by adjusting the position of the air mix damper 374. Is possible.

  Note that the switching damper 371, the switching damper 372, the switching damper 373, and the air mix damper 374 are driven by an actuator 361, an actuator 362, an actuator 363, and an actuator 364 that are controlled based on signals transmitted from the CU1, respectively.

  Immediately after the outlet side of the evaporator 321, an evaporator outlet side temperature sensor 23 for detecting the temperature at this position (evaporator outlet side temperature) is provided, and on the indoor side of the aspirator 316, an indoor temperature sensor 21 for detecting the indoor temperature. Also, an indoor humidity sensor 22 for detecting indoor humidity is provided, and these sensors are connected to the CU 1 and used for air conditioning control. Information on the detected indoor temperature and the detected indoor humidity by the indoor temperature sensor 21 and the indoor humidity sensor 22 input to the CU1 is also transmitted to the humidity sensor abnormality determination unit of the CU1.

  An outside air temperature sensor 27 that detects the temperature of the outside air and a solar radiation amount sensor 28 that detects the amount of solar radiation are connected to the CU 1, and air conditioning control is corrected using the detected outside air temperature and the detected amount of solar radiation.

  Furthermore, the door sensor 24 and the window sensor 25 are connected to the CU1, and information regarding the open / closed state of the window and the door is input to the humidity sensor abnormality determination unit of the CU1.

  A car navigation system N having a GPS (Global Positioning System) antenna 26 is connected to the CU 1. Among the information transmitted from the GPS received by the GPS antenna 26, the current date and time information is Input to the humidity sensor abnormality determination unit of CU1.

  The detected indoor temperature, detected evaporator outlet side temperature, detected window open / closed state, detected door open / closed state, and received current date / time information input to the humidity sensor abnormality determination unit are the indoor humidity sensor 22 described later. It is used for abnormality determination processing.

  Reference numerals 322, 323, 324, and 325 are compressors, condensers, liquid tanks, and expansion valves constituting the air-conditioning refrigeration cycle, respectively, and well-known techniques are applied, and reference numeral C is blown out from the defroster outlet 313 or the like. B is a body control unit (Body Control Unit) for integrated control of the electrical system of the vehicle body, and the detected window and door open / closed state is controlled via CU1. Is input to the humidity sensor abnormality determination unit.

  Reference numeral 11 denotes an EEPROM (Electronically Erasable and Programmable Read Only Memory) 11 in which date / time information of the start of deterioration of the indoor humidity sensor 22 (at the time of removal from the packaging material containing the desiccant) is stored. . This date / time information is used for abnormality determination processing of the indoor humidity sensor 22 described later.

  FIG. 2 is a flowchart showing an abnormality determination process of the humidity sensor 22 performed in the humidity sensor abnormality determination unit inside the CU 1 of the humidity sensor abnormality detection system having this configuration. Each step will be described below. The symbol “S” shown in FIG. 2 represents the following “step”.

  In step 1, the current date and time information is read from the GPS information received by the GPS antenna 26.

  In step 2, following step 1, detection of deterioration due to aging of the humidity sensor is performed from the date and time information of deterioration start of the indoor humidity sensor 22 stored in advance in the EEPROM 11 and the current date and time information received by the GPS antenna 26. The error is calculated as an estimated value. Based on actual measurement data that the actual indoor humidity is underestimated at a rate of approximately 1.5% per year, the detected indoor humidity is detected indoor humidity before correction × 1.015. (%) × Elapsed years from the start of deterioration.

  In step 3, following step 2, the detected indoor humidity by the indoor humidity sensor 22 is read.

  In step 4, following step 3, the detected indoor humidity by the humidity sensor 22 read in step 2 is corrected using the detection error calculated in step 2.

  Hereinafter, the “detected indoor humidity” means “detected indoor humidity by the indoor humidity sensor 22 × 1.015 × the number of years elapsed from the start of deterioration”.

  In Step 5, following Step 4, it is determined whether or not the air conditioner 3 is operating. This is determined by whether or not the compressor 322 included in the refrigeration cycle of the air conditioner 3 is operating.

  This is because the abnormality detection of the indoor humidity sensor 22 by this humidity sensor abnormality detection system is a function of preventing condensation (fogging of the windshield etc.) caused by cooling and heating by inaccurate detection of the indoor humidity due to the abnormality of the indoor humidity sensor 22. This is because the main purpose is to prevent the malfunction (such as controlling the air volume at the defroster outlet in accordance with the room humidity) from operating, and therefore it is assumed that the air conditioner 3 is in operation.

  If it is determined that the air conditioner 3 is in operation, the process proceeds to step 6, but if it is determined that the air conditioner 3 is not in operation, the process is terminated and the process is restarted from step 1.

  Hereinafter, when the process is completed, the process is resumed from Step 1. The same applies hereinafter.

  In step 6, following step 5, it is determined whether or not it is the inside air circulation mode, that is, whether or not the outside air inlet 312 is closed by the switching damper 371. This is to maintain the accuracy of the estimated indoor humidity used for determining the normal humidity range used for determining the abnormality of the indoor humidity sensor 22, as will be described later. For this reason, when it is determined that the internal air circulation mode is set, the process proceeds to step 7, but when it is determined that the internal air circulation mode is not set, the process ends.

  In step 7, it is determined whether or not a vehicle door (not shown) is closed. This determination is made based on information on the door open / closed state detected by the door sensor 24. If it is determined that the door is closed, the process proceeds to step 8. If the door is not closed, the process ends. This is to maintain the accuracy of the estimated indoor humidity used for determining the normal humidity range used for determining the abnormality of the indoor humidity sensor 22, as will be described later.

  In step 8, it is determined whether or not a vehicle window (not shown) is closed. This determination is made based on information on the window open / closed state detected by the window sensor 25. If it is determined that the window is closed, the process proceeds to step 8. If it is determined that the window is not closed, the process is terminated. This is to maintain the accuracy of the estimated indoor humidity used for determining the normal humidity range used for determining the abnormality of the indoor humidity sensor 22, as will be described later.

  In step 9, counting of the set time of 30 minutes set in the internal timer included in CU1 is started.

  In step 10, following step 9, it is determined whether or not the set 30 minutes have elapsed. If 30 minutes have not elapsed, the processing from step 1 to step 10 is repeated until 30 minutes have elapsed. At this time, unless the timer is reset, the process of step 9 is not performed. When 30 minutes have elapsed, the process proceeds to step 12.

  Step 11 is executed when it is determined in steps 5 to 8 that the conditions of each step are not satisfied, and the elapsed time information of the timer is reset.

  In step 12, following step 10, the detected evaporator outlet side temperature detected by the evaporator outlet side temperature sensor 23 is read.

  In step 13, following step 12, the detected room temperature detected by the room temperature sensor 21 is read.

  In step 14, following step 13, a normal humidity range is determined using the detected evaporator outlet side temperature read in step 12 and the detected room temperature read in step 13. This determination process will be described later.

  In step 15, following step 14, it is determined whether or not the indoor humidity detected by the indoor humidity sensor 22 is within the normal humidity range determined in step 14.

  In Step 16, when the detected indoor humidity detected by the indoor humidity sensor 22 is in the normal humidity range determined in Step 14 following Step 15, the process proceeds to Step 16, and the detected indoor humidity is not in the normal humidity range. The process ends.

  In step 17, following step 16, counting of a set time of 1 minute set in the internal timer included in CU1 is started.

  In step 18, following step 17, it is determined whether or not the set 1 minute has elapsed. When 1 minute has not passed, the process from step 1 to step 18 is repeated until 1 minute passes. At this time, unless the timer is reset, the process of step 17 is not performed. If this one minute has elapsed, the routine proceeds to step 19.

  In Step 19, following Step 18, the warning light A is turned on.

  In step 20, following step 19, the temperature control of the evaporator 321 is prohibited.

  In step 21, following step 20, the temperature of the evaporator 321 is fixed to a constant temperature. This temperature is a temperature after the detection room humidity is not in the normal humidity range for a set time.

  Step 22 is executed when it is determined in step 16 that the condition of this step is not satisfied, and the elapsed time information of the timer is reset.

  In the above configuration, the EEPROM 11 is a storage unit, the GPS antenna 26 is a date / time information receiving unit, step 2 in this flowchart is a detection error estimation unit, step 4 is a detection humidity correction unit, and steps 6 to 11 are steps. Step 14 corresponds to the normality range determination means, step 15 and 16 correspond to the detection result collation means, step 19 corresponds to the abnormality notification means, and steps 20 and 21 correspond to the temperature control prohibition means.

  FIG. 3 is a flowchart showing the process of determining the normal humidity range in step 14 in the process of determining the abnormality of the humidity sensor 22 performed in the humidity sensor abnormality determination unit inside the CU 1 of the humidity sensor abnormality detection system having this configuration. Hereinafter, each step will be described.

  In step 141, the evaporator outlet side temperature detected by the evaporator outlet side temperature sensor 23 is read.

  In step 142, following step 141, the evaporator outlet side humidity (humidity immediately after the outlet side of the evaporator 321) stored in advance in the EEPROM 11 is read. Here, the maximum value of the evaporator outlet side humidity is set to 95% based on the knowledge that it is approximately 95%.

  In step 143, following step 142, the evaporator outlet side water vapor pressure (water vapor pressure immediately after the outlet side of the evaporator 321) is calculated. In this calculation, the relationship of “evaporator outlet side humidity = (evaporator outlet side water vapor pressure / evaporator outlet side saturated water vapor pressure) × 100” is used. Note that the evaporator outlet side saturated water vapor pressure (water pressure immediately after the evaporator outlet side) is “evaporator outlet side saturated water vapor pressure = 6.1121 × Exp (17.502 × evaporator outlet side temperature / (evaporator outlet side temperature + 240. 9) "is used.

  In step 144, following step 143, the detected indoor temperature by the indoor temperature sensor 21 is read.

  In step 145, following step 144, the indoor saturated water vapor pressure is calculated using the detected indoor temperature read in step 144. In this calculation, the relationship “indoor saturated water vapor pressure = 6.1121 × Exp (17.502 × indoor temperature / (indoor temperature + 240.9))” is used.

  In step 126, following step 125, the indoor humidity is calculated using the evaporator outlet side water vapor pressure calculated in step 123 and the indoor saturated water vapor pressure calculated in step 124. In this calculation, a relationship of “indoor humidity≈ (evaporator outlet side water vapor pressure / indoor saturated water vapor pressure) × 100” is used.

  Here, in the approximate expression of indoor humidity, the evaporator outlet side water vapor pressure is used as the indoor water vapor pressure. This is because when the space including the evaporator outlet side and the room communicates in a closed system, the evaporator outlet side water vapor pressure and the indoor water vapor pressure have the same value regardless of the air temperature. Because. Therefore, if it is not appropriate to treat as the same value, that is, if it is not the inside air circulation mode, the door is not closed, or the window is not closed, the indoor humidity is not estimated. (Steps 6-8). This is because outside air is mixed, the evaporator outlet water vapor pressure and the indoor water vapor pressure do not match, and the estimation accuracy of the indoor humidity decreases.

  In step 147, following step 146, ± 10% is added as an allowable error to the estimated indoor humidity calculated in step 146 to determine the normal humidity range.

Next, the operation will be described.
In the humidity sensor abnormality determination unit of the CU 1, current date / time information is acquired from the GPS (step 1), and from the current date / time information and date / time information at the start of deterioration of the indoor humidity sensor 22 stored in the EEPROM 11 in advance. Then, a detection error (aging deterioration error) due to aging deterioration is calculated (step 2).

  Then, the detected indoor humidity by the indoor humidity sensor 22 is read (step 3), and the detected indoor humidity is corrected by using the already calculated aging degradation error (step 4). For this reason, the detection of the indoor humidity by the indoor humidity sensor 22 is performed with an accuracy close to the accuracy at the time of opening.

After the detection room humidity correction process (steps 1 to 4) is executed, the process proceeds to step 5. When it is determined in step 5 that the air conditioner is not ON, the abnormality detection process of the indoor humidity sensor 22 is not executed, but the processes from step 1 to step 4 are always executed.
That is, the correction of the detected indoor humidity by the indoor humidity sensor 22 is always performed independently of the abnormality determination of the indoor humidity sensor 22.

  Subsequent to Step 1 to Step 4, the processing from Step 5 to Step 8 is sequentially executed.

  In addition, the outside water is mixed by the determination process from step 6 to step 8, so that the indoor water vapor pressure fluctuates, and the difference between the indoor water vapor pressure and the evaporator outlet water vapor pressure becomes large, and the accuracy of estimating the indoor humidity is increased. In the case of a decrease (reduced reliability of abnormality determination of the indoor humidity sensor 22), the process is terminated, and the subsequent indoor humidity estimation process is performed only when the accuracy of the indoor humidity estimation does not decrease. It has become. As described above, the estimated indoor humidity used for determining the abnormality of the indoor humidity sensor 22 assumes that the indoor water vapor pressure is equal to the evaporator outlet water vapor pressure, and the evaporator outlet water vapor pressure is used instead of the indoor water vapor pressure. This is because the accuracy of the approximate calculation by this substitution is maintained.

  Here, even when the air conditioner 3 is in operation and is in the inside air circulation mode and the door and window are closed, it is determined whether the air conditioner 3 is turned on and off, the inside / outside air circulation mode is switched, the door or When the opening / closing operation of the window is performed, the indoor water vapor pressure fluctuates for a while, which may reduce the accuracy of the estimated indoor humidity calculated based on the indoor water vapor pressure. However, the determination process of step 5 to step 8 is repeated until the end of the 30-minute count set in the internal timer as the time required for the indoor water vapor pressure to converge to a constant value by the determination process of step 10. Therefore, a decrease in the accuracy of the estimated indoor humidity is prevented.

  When it is determined that the conditions in Steps 5 to 8 are not satisfied during the execution of the determination processes from Step 5 to Step 8 that are executed until the above-described 30-minute count ends, for example, a door If the timer is released even if it is temporary, the elapsed time information of the timer is reset. When all the conditions in step 5 to step 8 are satisfied again, the count of 30 minutes set in the timer in step 9 is started.

  Subsequent to step 10, the processing from step 12 to step 15 is sequentially executed. That is, the evaporator outlet side temperature is acquired (step 12), the room temperature is acquired (step 13), the normal humidity range corresponding to both these temperatures is determined (step 14), and the detected room humidity (corrected in step 4). The detected humidity in the room is compared with the normal humidity range (step 15).

  If the detected indoor humidity is in the indoor normal range, the process proceeds to step 18, the elapsed time information of the timer is reset, the process ends, and the process is restarted from step 1.

  When the detected indoor humidity does not exist in the normal humidity range, the indoor humidity sensor 22 is determined to be abnormal, but before the warning light A is lit (shifted to step 19), the timer is set by step 17 One minute starts counting, and the processing from step 1 to step 17 is repeated until this one minute is counted.

  For this reason, the determination that the detected indoor humidity does not exist in the normal humidity range is to reduce the possibility of being caused by noise, and the one-minute iterative process from step 1 to step 17 is completed, that is, detection is performed. If the indoor humidity does not exist in the normal humidity range for 1 minute, the warning light A for informing the passenger of the abnormality of the indoor humidity sensor 22 is turned on in step 19.

  Then, after the warning lamp A is turned on, the temperature control of the evaporator 321 (the discharge amount control of the compressor 322) is prohibited, and the refrigerant temperature of the evaporator 321 is set to the temperature during the warning lamp A lighting process (the above-mentioned 1 minute). It is fixed at the temperature after elapse).

Next, the effect will be described.
In the humidity sensor abnormality detection system of the present embodiment, the effects listed below can be obtained.

  (1) In the humidity sensor abnormality detection system of the present invention, whether the indoor humidity sensor 22 is normal or abnormal is detected by the indoor humidity sensor 22 by the detection result checking means (steps 15 and 16). Whether the indoor humidity (indoor humidity) is within the normal humidity range is determined.

  The normal humidity range is estimated by the normal humidity range determining means (steps 141 to 148) using the indoor temperature when detecting the indoor humidity and the evaporator outlet side temperature when detecting the indoor humidity. It is determined based on humidity (estimated indoor humidity).

  For this reason, the normal humidity range used to determine the normal humidity range used to determine whether the indoor humidity is normal or abnormal is constantly updated according to the indoor humidity at the time of detecting the indoor humidity, and approximates the actual indoor humidity. Since it is based on the estimated indoor humidity, the reliability of determination by the detection result determination means is high.

  (2) By the estimable condition determination means (steps 6 to 11), it is the inside air circulation mode, the door and the window are closed, and this state is maintained for a predetermined set time (30 minutes) (estimable) Since the humidity normal range is determined by the humidity normal range determination means (steps 141 to 148) only when the accuracy of the humidity normal range is not impaired, Furthermore, highly reliable abnormality detection is possible.

  (3) Even if the rate of underestimation of the actual indoor humidity increases due to an increase in the aging degradation error of the indoor humidity sensor 22, the detected indoor humidity is detected by the detected humidity correction means (step 4) and the deterioration start date / time information. Aged deterioration error of the indoor humidity sensor 22 is corrected using the current date and time information. For this reason, it is prevented that the detected indoor humidity does not satisfy the normal humidity range due to an increase in the aging deterioration error, so that the lighting timing of the warning lamp A is extended and the replacement timing of the indoor humidity sensor 22 is extended.

  In addition, since the aging deterioration error of the indoor humidity sensor 22 is corrected using the date and time information on the start of deterioration and the current date and time information, it is possible to calculate the accumulated aging deterioration that takes into account the time during which the CU 1 is not energized. .

  (4) Since current date and time information of GPS information received by the GPS antenna 26 is always input to the CU 1, correction of detection errors due to aging deterioration always uses accurate date and time information and accurate detection accuracy. In addition, it is not necessary for the passenger to manually input the current date and time information.

  (5) While an abnormality of the indoor humidity sensor 22 is detected by the humidity sensor abnormality determination unit, the temperature control prohibiting means (steps 21 and 22) temporarily controls the temperature of the evaporator 321 (the discharge amount control of the compressor 322). ) Is prohibited, and the temperature of the evaporator 321 is maintained at the temperature when the abnormality of the indoor humidity sensor 22 is detected (when the warning light A is lit). For this reason, even if the function of preventing condensation due to the cooling / heating control performed using the room humidity is not effective due to an abnormality in the indoor humidity sensor 22, the occurrence / increase of condensation can be suppressed.

  (6) When it is determined that the indoor humidity sensor 22 is abnormal by the detection result collating means (steps 14 and 15), the warning lamp A for notifying abnormality is turned on by the abnormality notifying means (step 16). Therefore, it becomes easy for the passenger to determine when to replace the indoor humidity sensor 22.

Although the embodiments have been described above, the present invention is not limited to the embodiments, and design changes and additions are permitted without departing from the spirit of the invention according to the claims.
For example, the indoor humidity is estimated corresponding to the room temperature and the evaporator outlet side temperature using an experiment or the above-described calculation formula in advance, and the normal humidity range is determined based on this indoor humidity (estimated indoor humidity). Is stored in the EEPROM 11 as a table value, and the humidity normal range determination means of the humidity sensor abnormality determination unit of the CU 1 corresponds to the detected indoor temperature and the detected evaporator outlet side temperature when the detected indoor humidity is acquired from the EEPROM 11. The table value is read, and the detection result determination means determines whether or not the detected indoor humidity is in the normal humidity range as the table value, thereby determining the abnormality of the indoor humidity sensor 22. .

  In this case, for example, the indoor humidity is measured a plurality of times under the same temperature conditions (evaporator outlet side temperature and room temperature), the average value is set as the estimated room humidity, and the normal humidity range determined based on this is set as the table value. It can be. For this reason, the accuracy of the normal humidity range can be improved, and the reliability of the abnormality determination of the indoor humidity sensor 22 can be improved.

  Further, the timer time counted in step 9 can be arbitrarily set in consideration of the estimation accuracy of the indoor humidity. Similarly, the timer time counted in step 17 can be arbitrarily set in consideration of erroneous determination due to noise.

  Further, the allowable error of the estimated indoor humidity in step 147 can be arbitrarily set in consideration of the accuracy of the abnormality determination of the indoor humidity sensor 22.

  In step 21, the temperature control of the evaporator 321 is prohibited, and in step 22, the temperature of the evaporator 321 is fixed at the temperature when the abnormality of the indoor humidity sensor 22 is detected (when the warning light A is lit). Instead of this, the amount of blowout at the defroster blowout port may be increased, or the air temperature at this blowout port may be increased.

It is the schematic which shows the whole structure of a humidity sensor abnormality detection system. It is a flowchart which shows the flow of a process of an abnormality detection of the indoor humidity sensor by a humidity sensor abnormality detection system. It is a flowchart which shows the flow of a process of determination of the humidity normal range used for abnormality detection of an indoor humidity sensor.

Explanation of symbols

1 Air conditioning control unit (humidity sensor abnormality determination unit)
11 EEPROM (storage means)
26 GPS antenna (date information receiving means)
S2 Detection error estimation means S4 Detection humidity correction means S6 to S11 Estimable condition determination means S14 Normal humidity range determination means S15, S16 Detection result determination means S20 Abnormality notification means S21, S22 Temperature control prohibition means

Claims (8)

Detection result determination means for determining whether or not the detected indoor humidity detected by the indoor humidity sensor is in a normal humidity range;
The normal humidity range is a detected indoor temperature detected by an indoor temperature sensor when the detected indoor humidity is acquired, and a detected evaporator outlet temperature detected by the evaporator outlet temperature sensor when the detected indoor humidity is acquired. And a humidity normal range determining means for determining based on the estimated indoor humidity according to
A humidity sensor comprising a humidity sensor abnormality determining unit that determines whether the indoor humidity sensor is abnormal when the detected indoor humidity does not exist in the normal humidity range as a result of determination by the detection result determining means. Anomaly detection system.   The humidity normal range determination means uses the estimated indoor humidity using the indoor saturated water vapor pressure calculated using the detected indoor temperature and the evaporator outlet water vapor pressure calculated using the detected evaporator outlet side temperature. The humidity sensor abnormality detection system according to claim 1, wherein the humidity sensor abnormality detection system is estimated. Using an experiment or a calculation formula in advance, the indoor humidity is estimated corresponding to the room temperature and the evaporator outlet side temperature, and the normal humidity range is determined based on the indoor humidity,
The humidity sensor abnormality determination unit includes a storage unit that stores the normal humidity range determined based on the presumed indoor humidity as a table value.
The humidity normal range determining means reads out the table value corresponding to the detected room temperature and the detected evaporator outlet side temperature at the time of obtaining the detected indoor humidity from the storage means,
2. The humidity sensor abnormality detection system according to claim 1, wherein the detection result determination unit determines whether or not the detected indoor humidity is in a normal humidity range as the read table value. . The humidity sensor abnormality determining unit includes an estimable condition determining unit that determines whether or not an estimable condition for maintaining the accuracy of the estimated indoor humidity is satisfied,
The detection result determination unit does not perform the determination when it is determined by the estimable condition determination unit that the humidity estimation accuracy maintenance condition is not satisfied. The humidity sensor abnormality detection system described in 1. The humidity sensor abnormality determination unit includes date and time information receiving means for receiving current date and time information by radio waves,
Using the date and time information, detection error estimation means for estimating a detection error due to aging of the indoor humidity sensor,
Detecting humidity correction means for correcting the detected indoor humidity using the detection error,
5. The humidity sensor abnormality according to claim 1, wherein the detection result determination unit determines whether or not the corrected detected indoor humidity exists in the normal humidity range. Detection system.   6. The humidity sensor abnormality detection system according to claim 5, wherein the date / time information receiving means receives current date / time information from a GPS.   The humidity sensor abnormality determination unit prohibits control of the room temperature and maintains the room temperature at a predetermined temperature when the detection result determination unit determines that the detected room humidity does not exist in the normal humidity range. The humidity sensor abnormality detection system according to any one of claims 1 to 6, further comprising temperature control prohibiting means. 8. The apparatus according to claim 1, further comprising an abnormality notifying unit that notifies the abnormality when the detection result determining unit determines that the detected indoor humidity does not exist in the normal humidity range. The humidity sensor abnormality detection system described in 1.

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