Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N25/00—Investigating or analyzing materials by the use of thermal means
  • G01N25/56—Investigating or analyzing materials by the use of thermal means by investigating moisture content
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
  • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
  • G01N33/0004—Gaseous mixtures, e.g. polluted air
  • G01N33/0009—General constructional details of gas analysers, e.g. portable test equipment
  • G01N33/007—Arrangements to check the analyser

Definitions

• the invention relates to a method for operating a sensor module having a humidity sensor for determining the relative humidity, wherein by means of the humidity sensor at least one measured value for the relative
• the invention further relates to a corresponding sensor module. Disclosure of the invention
• Moisture sensor at least a second measured value for the relative humidity by means of the humidity sensor is determined, and that depending on the first and second measured value to an operating condition and / or a
• the inventive principle is based on a targeted "detuning" of a significant operating condition of the humidity sensor, namely the Ambient temperature. According to investigations by the Applicant, the relative humidity in the region of the humidity sensor changes with the ambient temperature in accordance with the thermodynamic known to the person skilled in the art
• an error of the humidity sensor can then be inferred if the first and the second measured value for the relative air humidity do not differ at least by a predefinable difference value, which is preferably selected as a function of the temperature change.
• Tempering device increases before the second measured value is determined. This requires a particularly low design effort for the realization of the tempering, for example in the form of an electrical
• the ambient temperature in the range of the humidity sensor also reduce, for example by means of a Peltier element.
• a change in the ambient temperature in the region of the humidity sensor is understood, in particular, to mean the change in the temperature of a medium surrounding the humidity sensor, for example air.
• the sensor module has an air mass sensor
• a heating element of the air mass sensor as
• Tempering device is used to change the ambient temperature in the range of the humidity sensor. For this purpose, a constructive arrangement of Heating element and the humidity sensor relative to each other so required that by means of the heating element targeted the ambient temperature of the
• Humidity sensor can be influenced. If the air mass sensor or its heating element separated from the remaining sensor module
• the humidity sensor or can be supplied to the humidity sensor or supplied with electrical energy can be advantageously provided to selectively activate the air mass sensor or its heating element and / or to disable to change the ambient temperature in the range of the humidity sensor.
• Air mass sensors usually have a heating device which is adapted to heat other components of the air mass sensor in a conventional manner.
• a temperature change namely cooling
• a temperature change can thus advantageously be effected in the surroundings of the humidity sensor, which makes it possible to check a function of the humidity sensor by balancing different measured values for the relative air humidity at different temperatures.
• a further solution of the object of the present invention is given by a method according to claim 6.
• a temperature and an air pressure in the range of the humidity sensor is determined.
• the temperature and the air pressure is at least one limit for the absolute
• Limit value or the limits for the absolute water content of the air can be closed according to the invention again advantageous to an operating condition and / or proper operation of the humidity sensor. Namely, for example, a relative humidity is output by the humidity sensor, which in contradiction to the invention of temperature and
• Air pressure determined theoretical limit of the absolute water content stands, it can be concluded advantageous to a defect of the humidity sensor or the other sensors involved (air pressure, temperature).
• FIG. 1 shows schematically a simplified block diagram of a first
• FIG. 2 shows a simplified flowchart of an embodiment of a
• FIG. 4 shows a simplified flowchart of an embodiment of a
• FIG. 1 schematically shows a sensor module 100, as used, for example, in the field of motor vehicles for determining a relative air humidity.
• the sensor module 100 has a measuring channel 102, through which a gaseous medium 104 passes for the purpose of moisture measurement.
• a humidity sensor 110 is arranged in the region of the measuring channel 102 and designed to detect the relative humidity of the medium 104 passing through the measuring channel 102.
• the sensor module 100 has, in addition to the humidity sensor 110
• Temperature control 120 which is adapted to a
• Ambient temperature in the range of the humidity sensor 1 10 to change for example, to reduce and / or increase.
• the tempering device 120 can heat or cool the medium to be measured (air 104) accordingly.
• FIG. 2 shows a simplified flow diagram of one embodiment of an operating method for the sensor module 100.
• a first step 200 at least one first measured value for the relative air humidity of the air 104 (FIG. 1) is determined by means of the humidity sensor 110.
• the ambient temperature in the region of the humidity sensor 110 is changed by means of the tempering device 120, for example increased.
• the gaseous medium 104 in the region of the humidity sensor 1 10 may in principle contain a larger amount of water vapor, but the absolute water content of the medium 104 in the measuring channel 102 and in particular in the range of the humidity sensor 1 10 changes due to the heating by the tempering 120 not.
• the relative humidity in accordance with the laws of
• a third step 220 (FIG. 2), at least one second measured value for the relative air humidity is determined by means of the humidity sensor 110.
• an evaluation of the first and second measured values for the relative air humidity takes place with the aim of concluding the operating state or a proper operation or an error of the humidity sensor 110.
• the evaluation 230 may, for example, a difference of the two
• Humidity measured values are the subject, and it can be concluded that an error of the humidity sensor 1 10, if the first and second relative humidity are not different from each other by at least a predetermined difference. In this case, the humidity sensor would have 1 10 despite the inventive change 210 of
• the predetermined difference is preferred in
• step 230 If the difference, considered in step 230, of the two measured values for the relative air humidity, taking into account the valid thermodynamic relationships, corresponds sufficiently well to the change in the temperature caused by the tempering device 120 according to the invention
• Humidity sensor 1 10 closed.
• the air mass sensor 120a has an integrated heating element 120a '.
• the heating element 120a 'of the air mass sensor 120a may be used to measure the change in ambient temperature in the region of the
• Humidity sensor 1 10 to bring. This can be accomplished, for example, by selectively activating or deactivating the air mass sensor 120a or its heating element 120a '.
• the sensor module 100 can be embodied in one
• a second measured value for the relative humidity by the humidity sensor 1 10 determined. This second measured value is evaluated together with measured values for the relative humidity determined previously, that is to say when the air mass sensor 120 is activated, and accordingly increased ambient temperature of the humidity sensor 110, compare step 230.
• Temperature control device 120 which can both increase and decrease the ambient temperature, the inventive method can be advantageously applied in a wider ambient temperature range, whereby a more detailed diagnosis of a working area of
• Humidity sensor 1 10 is possible.
• the sensor module 100 may also have a temperature sensor and corresponding control electronics (not shown).
• FIG. 3 shows a further advantageous embodiment of a sensor module 100a, which has a humidity sensor 110 for determining the relative humidity of a gaseous medium 104 passing through the measuring channel 102.
• the sensor module further has an air pressure sensor 130 for determining an air pressure in the measuring channel 102 and a temperature sensor 140 for determining a temperature of the medium 104 passing through the measuring channel 102.
• a measured value for the relative humidity by means of the humidity sensor 1 10 is determined.
• the air pressure and by means of the temperature sensor 140 the temperature of the ambient air 104 in the measuring channel 102 determined.
• at least one limit value for the absolute water content of the gaseous medium 104 in the region of the humidity sensor 110 is determined, for example by means of a characteristic map. It is also possible to determine an upper and a lower limit value for the absolute water content of the gaseous medium 104. The limit value can also be determined, for example, using a characteristic map or the like.
• step 320 depending on the measured value for the relative air humidity and the limit value for the absolute water content of the air 104, an operating state and / or a proper operation or an error of the humidity sensor 110 are concluded. If, in fact, the value for the relative air humidity supplied by the humidity sensor 1 10 is inconsistent with the absolute water content determined in step 310, that of
• Temperature and air pressure in the measuring channel 102 depends on an error in at least one of the participating components 1 10, 130, 140 are closed.
• the sensor module 100a according to FIG. 3 can be supplemented, for example, by a tempering device 120 (FIG. 1) or by a device implementing the functionality of a tempering device 120
• Air mass sensor 120a Air mass sensor 120a.

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• Chemical & Material Sciences (AREA)
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• Life Sciences & Earth Sciences (AREA)
• Analytical Chemistry (AREA)
• Physics & Mathematics (AREA)
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• General Health & Medical Sciences (AREA)
• General Physics & Mathematics (AREA)
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• Pathology (AREA)
• Engineering & Computer Science (AREA)
• Food Science & Technology (AREA)
• Medicinal Chemistry (AREA)
• Combustion & Propulsion (AREA)
• Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
• Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)

Applications Claiming Priority (2)

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• 2010
  • 2010-06-22 DE DE102010030338A patent/DE102010030338A1/de not_active Withdrawn
• 2011
  • 2011-05-19 WO PCT/EP2011/058118 patent/WO2011160899A1/de active Application Filing
  • 2011-05-19 JP JP2013515788A patent/JP2013529776A/ja active Pending
  • 2011-05-19 CN CN2011800308229A patent/CN102947700A/zh active Pending
  • 2011-05-19 EP EP11721508.7A patent/EP2585821A1/de not_active Withdrawn
  • 2011-05-19 US US13/805,202 patent/US20130174644A1/en not_active Abandoned
  • 2011-05-19 KR KR1020127033366A patent/KR20130116793A/ko not_active Application Discontinuation

Non-Patent Citations (1)

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