KR102546273B1 - Hydrogen gas sensor apparatus with relative hunidity compensation and measurement method of it - Google Patents

Abstract

A measuring method of a hydrogen gas sensor device of the present invention is a method of measuring a hydrogen sensor using temperature and humidity compensation, comprising: comparing an initial measurement value of hydrogen concentration with a predetermined reference value after power is applied to the hydrogen sensor; If the first measured value is smaller than a predetermined reference value, storing the applied offset at the current measurement time point; comparing a pre-stored applied offset at a previous measurement point in time with an applied offset at the current measurement point in time; If the applied offset at the current measurement time point is greater than the applied offset at the previous measurement time point, measuring the hydrogen concentration according to the applied offset at the current measurement time point; and if the applied offset at the current measurement time point is smaller than the applied offset at the previous measurement time point, measuring the hydrogen concentration according to the applied offset at the previous measurement time point.

Description

Hydrogen gas sensor device and measurement method with relative humidity compensation {HYDROGEN GAS SENSOR APPARATUS WITH RELATIVE HUNIDITY COMPENSATION AND MEASUREMENT METHOD OF IT}

In the present invention, after the temperature/humidity compensation is completed immediately after the power of the hydrogen sensor is turned on, relative humidity compensation is applied to accurately correct deviations in the initial measured value due to manufacturing deviation/durability deterioration of the hydrogen concentration output by the hydrogen sensor. It relates to a hydrogen gas sensor device and measuring method.

In general, the prospects for fossil fuels are not bright. Recently, with the emergence of new large energy consuming countries such as China and India, the period of use based on reserves is expected to be shortened. Accordingly, research to replace fossil fuels with hydrogen energy is being conducted worldwide.

Hydrogen energy is in the limelight as a storage medium for various alternative energies for energy supply and demand problems.

Hydrogen is being researched worldwide as a clean energy source, and is currently being used in various fields such as fuel cells and internal combustion engines.

However, since hydrogen has a high flash point and explodes when its concentration exceeds a certain level, the need for a hydrogen sensor capable of detecting whether or not there is a leak of hydrogen in the process of handling it is considered important.

On the other hand, facilities such as storage facilities for chemical and/or radioactive products, geothermal drilling, warehouse sites and industrial tanks may be at risk of hydrogen releases related to stored products, which releases are explosive and can cause human harm. may be placed in an environment that is detrimental to There is also a need in the foregoing fields to control the risk and to detect prophylactically any hydrogen release that may occur.

In particular, in the case of a fuel electric vehicle (FCEV), which is expected to be the most widely used field of hydrogen energy, it greatly depends on a hydrogen sensor mounted on a fuel cell stack to increase energy efficiency and stability.

As a result, as a hydrogen sensor that inspects the leakage of hydrogen gas, for example, a sensor using an electrical method using the change in electrical conductivity of a metal when hydrogen is adsorbed on a metal such as platinum or palladium, a sensor using an oxide semiconductor type and a gas MOSFET, etc. A sensor using an electrochemical method and a sensor using an optical method for detecting hydrogen leakage using light have been developed.

Among them, in the case of a heat conduction type hydrogen sensor with excellent cost efficiency, that is, economical efficiency, the heat conduction value due to the hydrogen concentration in the air is affected by the temperature / humidity value in the air, which is affected by the atmospheric temperature / relative humidity. It is applied in a way to determine the hydrogen concentration by compensating the thermal conductivity value for

In the case of the automotive relative humidity sensor applied to compensate the hydrogen sensor of the heat conduction method, a method in which a dehumidifying agent is applied is common. will affect In addition, when the desiccant is poisoned by VOC or the like, the relative humidity sensor may be poisoned and degraded.

As a result, the thermal conductivity value is compensated with an incorrect relative humidity value, resulting in a decrease in the hydrogen concentration detection performance in the air. For example, if the relative humidity is measured to be higher than the actual value and compensated for, the hydrogen concentration is compensated with a low value. In this case, when actual hydrogen gas leaks in the environment where the hydrogen sensor is installed, an accurate leakage amount cannot be measured.

On the other hand, in the industrial cooperation system in which manufacturers of each part are independent, in the case of a company using a product of a thermal conduction type hydrogen sensor that performs the temperature and humidity compensation, since it is not a manufacturer of the hydrogen sensor, the hydrogen The measurement value of the hygrometer provided in the detection sensor cannot be directly compensated, and only the final hydrogen concentration measurement value of the hydrogen detection sensor can be obtained.

In the above-described situation, when the hydrogen sensor of the heat conduction type is left in a high humidity environment or VOC in an environment equipped with, a method for determining actual hydrogen gas leakage without missing it is necessary.

Republic of Korea Registration No. 10-1490178

The present invention is to provide a hydrogen gas sensor device and measurement method to which relative humidity compensation is applied, which can cope with a phenomenon in which the hydrogen concentration sensing performance deteriorates when the humidity sensor deteriorates due to durability deterioration or VOC poisoning deterioration. .

The present invention is a relative humidity that accurately corrects deviations that occur in the initial measurement value due to manufacturing deviations of hydrogen concentration output by the hydrogen sensor after temperature/humidity compensation is completed immediately after the power of the hydrogen sensor is turned on/durability degradation/VOC poisoning degradation, etc. It is intended to provide a hydrogen gas sensor device and measurement method to which compensation is applied.

A method for measuring a hydrogen gas sensor device according to an aspect of the present invention is a method for measuring a hydrogen sensor that applies temperature and humidity compensation, and compares an initial measurement value of hydrogen concentration with a predetermined reference value after power is applied to the hydrogen sensor. doing; If the first measured value is smaller than a predetermined reference value, storing the applied offset at the current measurement time point; comparing a pre-stored applied offset at a previous measurement point in time with an applied offset at the current measurement point in time; If the applied offset at the current measurement time point is greater than the applied offset at the previous measurement time point, measuring the hydrogen concentration according to the applied offset at the current measurement time point; and if the applied offset at the current measurement time point is smaller than the applied offset at the previous measurement time point, measuring the hydrogen concentration according to the applied offset at the previous measurement time point.

Here, when the offset to be applied during measurement is out of a predetermined reference limit, a step of correcting the applied offset with the reference limit may be included.

Here, in the step of correcting the applied offset with the reference limit, correction of the applied offset with the reference limit may be counted, and when the counted value reaches a predetermined reference number of times, it may be notified to the outside.

Here, in the step of measuring the hydrogen concentration according to the applied offset at the previous measurement time point, it is counted that the applied offset at the previous measurement time point is reflected, and when the counted value reaches a predetermined standard number of times, it is notified to the outside. can

A hydrogen gas sensor device to which relative humidity compensation is applied according to another aspect of the present invention includes a temperature sensor for measuring temperature; Humidity sensor for measuring humidity; A hydrogen sensor for measuring hydrogen gas concentration by thermal conduction; a correction calculation unit which calculates a corrected hydrogen gas concentration by performing correction according to the measured value of the temperature sensor and the measured value of the humidity sensor with respect to the measured value of the concentration of the hydrogen sensor; and an offset calculation unit that calculates a final hydrogen gas concentration by applying an initial measured value of hydrogen concentration as an applied offset to the corrected hydrogen gas concentration after power is applied, and records the applied offset in a non-volatile memory. .

Here, the offset calculation unit compares a corrected hydrogen gas concentration value initially calculated after power is applied to the hydrogen gas sensor device with a predetermined reference value; If the first calculated concentration value is less than a predetermined reference value, storing it as an applied offset at the current measurement time point; Comparing a pre-stored applied offset at a previous measurement point in time with an applied offset at a current measurement point in time; If the applied offset at the current measurement time point is greater than the applied offset at the previous measurement time point, measuring the hydrogen concentration according to the applied offset at the current measurement time point; and if the applied offset at the current measurement time point is smaller than the applied offset at the previous measurement time point, measuring the hydrogen concentration according to the applied offset at the previous measurement time point.

Here, the offset calculating unit may further perform a step of correcting the applied offset with the reference limit when the offset to be applied during measurement is out of a predetermined reference limit.

Here, the reference limit may be a value selected in consideration of product variation within the range of -0.1% to -0.5%.

When the hydrogen gas sensor device and/or measurement method to which relative humidity compensation is applied according to the spirit of the present invention having the above configuration is implemented, when the humidity sensor is left in a high humidity environment or VOC, the humidity sensor incorrectly measures the humidity, so that the hydrogen sensor is incorrectly detected. There is an advantage to avoid compensating the relative humidity with the value.

The hydrogen gas sensor device and/or measurement method to which relative humidity compensation is applied according to the present invention also stores the transition of the offset amount each time the ignition is turned on in the MCU EEPROM, so that the amount of hydrogen gas can be measured even in a situation where an actual hydrogen leak occurs. has the advantage of being able to detect accurately.

1 is a graph showing the thermal conductivity of hydrogen gas according to the relative humidity.
2 is a graph illustrating the concept of correcting an initial measurement value by considering it as an offset;
3 is a graph showing a state in which the hydrogen gas sensor device is operated by performing the offset correction of FIG. 2;
4 is a graph showing the relationship between a hydrogen gas sensor device and a humidity environment when vehicle startup ON-OFF is repeated.
5 is a graph showing a state in which the hydrogen concentration detection performance is continuously deteriorated in a section in which start-up ON-OFF is repeated.
Figure 6a is a graph showing the state of applying an offset to the hydrogen concentration value (temperature / humidity corrected value) sensed by the hydrogen gas sensor in section ② of FIG.
6B is a graph showing how an offset is applied when a value applied as an offset becomes larger than a point in time ② (|α|<<|β|).
FIG. 6C is a graph showing how an offset is applied when a value applied as an offset is similar to that of ② viewpoint (|α|≒|β|).
6D is a graph showing the risk of applying the offset when the value applied as the offset becomes smaller than the point of time ② (|α|>>|β|).
7 is a conceptual diagram illustrating a method proposed by the present invention when a value applied as an offset becomes smaller than a point in time ②.
8 is a flowchart illustrating an embodiment of a measuring method of a hydrogen sensor device according to the spirit of the present invention.
9 is a block diagram showing an embodiment of a hydrogen gas sensor device to which relative humidity compensation is applied according to the spirit of the present invention.

In describing the present invention, terms such as first and second may be used to describe various components, but the components may not be limited by the terms. Terms are only for the purpose of distinguishing one element from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present invention.

When a component is referred to as being connected or connected to another component, it may be directly connected or connected to the other component, but it may be understood that another component may exist in the middle. .

Terms used in this specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions may include plural expressions unless the context clearly dictates otherwise.

In this specification, the terms include or include are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features or numbers, It can be understood that the presence or addition of steps, operations, components, parts, or combinations thereof is not precluded.

In addition, shapes and sizes of elements in the drawings may be exaggerated for clearer description.

Prior to presenting a method for compensating for relative humidity in a heat conduction hydrogen gas sensor device according to the spirit of the present invention, the operation principle of the heat conduction hydrogen gas sensor and the durability deterioration of the humidity sensor and the problems caused therein will be reviewed.

1 is a graph showing the thermal conductivity of hydrogen gas according to the relative humidity.

Durability deterioration of the relative humidity sensor applied to compensate for the relative humidity of the thermal conduction type hydrogen gas sensor easily occurs. In general, a relative humidity sensor with a desiccant applied will experience durability deterioration of 0.5%RH per year, and a relative humidity deviation of 7.5%RH during a period of use of up to 15 years.

Also, when the dehumidifier is poisoned by VOCs (volatile organic compounds), the relative humidity is generally measured higher than that of the air.

As shown in FIG. 1, when the temperature in the air rises, the thermal conductivity of the gas changes according to the relative humidity. Therefore, it is possible to accurately measure the gas concentration by correcting the thermal conductivity by compensating for the actual relative humidity value in the air.

However, if the measurement is higher than the actual relative humidity in the atmosphere, the thermal conductivity is erroneously compensated in the subtraction direction, resulting in a problem of measuring the thermal conductivity lower than the actual one, which causes a problem in measuring the actual atmospheric humidity. This causes a problem in that the output is lower than the hydrogen gas concentration in the liquid.

In order to solve the problem that the hydrogen gas concentration is low, the following hydrogen sensor manufacturing deviation compensation logic may be reflected.

2 is a graph illustrating the concept of correcting an initial measured value by considering it as an offset.

3 is a graph showing a state in which the hydrogen gas sensor device is operated by performing the offset correction of FIG. 2 .

Right after the power of the hydrogen sensor (more precisely, the entire hydrogen gas sensor device including the humidity/temperature sensor and the calculation device) is turned on, the hydrogen sensor outputs the hydrogen concentration after temperature/humidity compensation is completed. At this time, the hydrogen sensor is manufactured. Deviation/durability deterioration/VOC poisoning deterioration may cause a deviation from the actual value of the first measured value.

Since it is common to point to 0% vol in normal atmospheric conditions (no hydrogen leakage) in terms of the performance of the hydrogen sensor, which must continuously detect hydrogen leakage until the power is turned on and turned off, as shown in FIG. Assuming that the hydrogen concentration output value immediately after being turned on is a manufacturing deviation (FRC) offset, as shown in FIG. 3, the hydrogen gas sensor device is operated by continuously correcting the corresponding manufacturing deviation (FRC) offset. can

However, since there is a possibility that actual hydrogen may leak after the power is turned on, it may cause serious danger to regard the first measurement value as a deviation unconditionally.

Therefore, the above-described offset correction is applied only when the first hydrogen gas concentration measurement value (calculated value reflecting temperature/humidity correction) is 0.1% vol or less. Additionally, since the negative hydrogen concentration is not real, an error of less than 0.0%vol can be cut-off as 0.0%vol.

In the above description, it is named as a manufacturing variance (FRC) offset, but in reality, not only the offset caused by the manufacturing variation, but also the offset due to durability deterioration and the offset due to VOC poisoning are included and observed.

The humidity sensor may suffer from durability degradation or VOC poisoning degradation, resulting in a problem in humidity sensing performance, resulting in a higher humidity measurement and, as a result, reduced hydrogen gas concentration sensing performance.

The durability degradation is not recovered, but the hydrogen concentration is gradually lowered, and the poisoning by the VOC can be gradually recovered when exposed to a general atmospheric environment from which VOC is removed for a long time.

The hydrogen sensor operates only when power is applied, and even when power is not applied, the humidity sensor may suffer from VOC poisoning or durability deterioration.

In particular, a lot of deterioration occurs in a situation where power is not applied for a long time, but if hydrogen gas is leaking at the time when power is turned on, it is difficult to accurately determine the degree of deterioration and leakage of hydrogen gas.

Next, a method and principle of applying an offset in relative humidity compensation in a heat conduction type hydrogen gas sensor device according to the spirit of the present invention will be described.

4 is a graph showing a relationship between a hydrogen gas sensor device and a humidity environment when vehicle startup ON-OFF is repeated.

4 is for explaining the mounting environment of the hydrogen gas sensor device, which is a target product of the present invention, and can be seen as an example of the mounting environment in the case of a hydrogen sensor mounted on a fuel cell stack of an FCEV vehicle.

As shown, when the engine is turned off, it is exposed to a high humidity environment of 80% or more, and when the engine is turned on, the low humidity of the atmospheric level is maintained. When a car user turns off the engine and leaves it for a long period of time (vehicles in stock/long-term neglected cars, etc.), they are exposed to a high-humidity environment of 80%RH or higher for a long period of time. At this time, the humidity sensor applied to the inside of the hydrogen sensor for compensation purposes is Under the influence of exposure, the desiccant absorbs moisture, causing erroneous humidity measurements.

5 is a graph showing a state in which hydrogen concentration sensing performance is continuously deteriorated in a section in which start-up ON-OFF is repeated.

6A is a graph showing how an offset is applied to a hydrogen concentration value (a temperature/humidity corrected value) sensed by a hydrogen gas sensor in section ② of FIG. 5, and FIG. 6B shows a value applied as an offset ② A graph showing the application of an offset when it is larger than the point of view (|α|<<|β|), and FIG. 6D is a graph showing the risk of applying the offset when the value applied as the offset becomes smaller than the point ② (|α|>>|β|).

In the graphs of FIGS. 5 and 6A to 6D, the similarity level criterion can be set within ±0.1% vol, and the corresponding value can be continuously updated according to repeated measurement results using the hydrogen gas sensor device.

Referring to each number section of FIGS. 5 and 6A to 6D , when the humidity sensor has deteriorated humidity sensing performance, a phenomenon risk in which the hydrogen concentration sensing performance is deteriorated will be described.

Section ① shows a gradual increase in offset due to durability deterioration or deterioration of the humidity sensor due to VOC poisoning. That is, the performance of the hydrogen sensor device gradually deteriorates.

Section ② is the starting-ON section during deterioration. If the amount of deterioration is recognized as a deviation when the power is turned on and applied (corrected) as an offset to the measured values afterwards, the hydrogen sensor device can be used effectively despite the progress of deterioration. there is.

Regardless of power on/off, the performance of the humidity sensor can be recovered when exposed to an environment in which VOCs are removed for a considerable period of time. Section ③ indicates that the performance of the humidity sensor is restored to some extent. This finally means that the performance degradation of the hydrogen gas sensor device is recoverable.

However, as in section ④, gradual deterioration may continue, so at the time of power on, it is unknown whether the hydrogen gas sensor (humidity sensor) has been recovered according to section ③ or whether hydrogen has been leaked and detected in section ④. can't

④-1 is the case where the value applied as the offset becomes larger than the point ②. In general, it gradually increases as the deterioration proceeds, so it is not a problem because it is just determined as a deviation (offset) and compensated for the deviation (applying the offset). .

④-2 is a case where the value applied as an offset is similar to that of ②, and since the front and back offsets are the same anyway, it is not a problem because deviation compensation (applying the offset) can be performed as it is.

If the value applied as the offset in ④-3 is smaller than the point in time ②: it is not distinguished among the following two cases, which makes it difficult to judge arbitrarily.

Possibility that the degree of deterioration of humidity performance of SHT has been recovered by case 1) ③

Possibility that hydrogen was leaking when the power was turned on in case 2) ④

7 is a conceptual diagram illustrating a method proposed by the present invention when a value applied as an offset becomes smaller than a point in time ②.

First, when the humidity sensor is left in a high-humidity environment for a long time and the humidity sensing performance is deteriorated, as a main response to the risk of deterioration in the hydrogen concentration sensing performance, the value compensated by the offset at each start-up time of the MCU Saving in EEPROM (non-volatile memory), continuously comparing the trend of the offset compensation value, grasping the amount of offset compared to the previous start-up time, and selecting the offset compensation value presents

In addition, depending on the implementation, as an additional response to the above risk, the maximum allowable offset correction value may be selected no matter how far apart α and β are. For example, when -0.2%vol is selected, even if the degree of deterioration exceeds -0.2%, the offset can be reflected by treating the correction value as -0.2%. In the above description, -0.2% was selected, but it is possible to select other values within the range of -0.1 to -0.5 in consideration of product variation.

8 is a flowchart illustrating an embodiment of a measuring method of a hydrogen sensor device according to the spirit of the present invention.

The method of measuring the hydrogen sensor device using the illustrated temperature and humidity compensation includes comparing an initial measurement value of hydrogen concentration with a predetermined reference value after power is applied to the hydrogen sensor (S110); If the first measurement value is smaller than a predetermined reference value (S120), storing the current measurement time as an applied offset (S140); Comparing a pre-stored applied offset at a previous measurement point in time with an applied offset at the current measurement point in time (S150); If the applied offset at the current measurement time point is greater than the applied offset at the previous measurement time point (S152), measuring the hydrogen concentration according to the applied offset at the current measurement time point (S160); and if the applied offset at the current measurement time point is smaller than the applied offset at the previous measurement time point (S156), measuring the hydrogen concentration according to the applied offset at the previous measurement time point (S170).

As shown, if the offset to be applied when performing measurement as a result of performing step S160 or S170 is out of a predetermined reference limit (S180), correcting the applied offset with the reference limit (S190). can do.

Depending on the implementation, in the step of measuring the hydrogen concentration according to the applied offset at the previous measurement time point (S170), it is counted that the applied offset at the previous measurement time point is reflected, and the counted value reaches a predetermined reference number of times, This can be notified externally. The driver manager receiving the notification may check whether the vehicle is operated (mainly parked) in a high humidity environment or an environment exposed to VOCs.

Depending on implementation, in the step of correcting the applied offset with the reference limit, correcting the applied offset with the reference limit may be counted, and when the counted value reaches a predetermined reference number of times, this may be notified to the outside. . The driver or manager receiving the notification may check whether the degree of durability deterioration of the humidity sensor provided in the hydrogen gas sensor device of the vehicle is excessive enough to consider replacement.

In the illustrated step S120, when the initial measurement value is smaller than the predetermined reference value, the offset is not applied, and the humidity/temperature corrected hydrogen gas concentration measurement value is used as it is (S130).

In the illustrated step S195, the offset determined according to the idea of the present invention is reflected in the humidity/temperature corrected hydrogen gas concentration measurement value and used as the final hydrogen gas concentration measurement value.

9 is a block diagram illustrating an embodiment of a hydrogen gas sensor device to which relative humidity compensation is applied according to the spirit of the present invention.

The illustrated hydrogen gas sensor device to which relative humidity compensation is applied includes a temperature sensor 110 for measuring temperature; Humidity sensor 120 for measuring humidity; Hydrogen sensor 140 for measuring the hydrogen gas concentration by thermal conduction method; a correction operation unit 162 that calculates a corrected hydrogen gas concentration by performing correction according to the measured value of the temperature sensor and the measured value of the humidity sensor with respect to the measured value of the concentration of the hydrogen sensor 140; and an offset calculation unit 164 for calculating a final hydrogen gas concentration by applying an initial measurement value of hydrogen concentration after power is applied to the corrected hydrogen gas concentration as an application offset, and recording the application offset in a non-volatile memory 166 ) may be included.

As shown, the correction operation unit 162, the offset operation unit 164, and the non-volatile memory 166 may be implemented in the form of an MCU 160 as a programmable microcontroller. In this case, the offset calculation unit 164 performing the measuring method of the hydrogen sensor device according to the spirit of the present invention may be implemented in the form of a software module inside the MCU 160.

That is, the offset calculator 164 compares the corrected hydrogen gas concentration value initially calculated after power is applied to the hydrogen gas sensor device with a predetermined reference value; If the first calculated concentration value is less than a predetermined reference value, storing it as an applied offset at the current measurement time point; Comparing a pre-stored applied offset at a previous measurement point in time with an applied offset at a current measurement point in time; If the applied offset at the current measurement time point is greater than the applied offset at the previous measurement time point, measuring the hydrogen concentration according to the applied offset at the current measurement time point; and if the applied offset at the current measurement time point is smaller than the applied offset at the previous measurement time point, measuring the hydrogen concentration according to the applied offset at the previous measurement time point.

In addition, the offset operator 164 may additionally perform a step of correcting the applied offset with the reference limit, if the offset to be applied during measurement is out of a predetermined reference limit.

Those skilled in the art to which the present invention pertains should understand that the embodiments described above are illustrative in all respects and not limiting, since the present invention can be embodied in other specific forms without changing the technical spirit or essential characteristics thereof. only do The scope of the present invention is indicated by the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention. .

110: temperature sensor 120: humidity sensor
140: hydrogen sensor 160: MCU
162: correction calculation unit 164: offset calculation unit
166: non-volatile memory

Claims (8)

As a method of measuring a hydrogen sensor that applies temperature and humidity compensation for durability deterioration or VOC poisoning deterioration,
comparing an initial measurement value of hydrogen concentration with a predetermined reference value after power is applied to the hydrogen sensor;
If the first measured value is smaller than a predetermined reference value, storing the applied offset at the current measurement time point;
comparing a pre-stored applied offset at a previous measurement point in time with an applied offset at the current measurement point in time;
If the applied offset at the current measurement time point is greater than the applied offset at the previous measurement time point, measuring the hydrogen concentration according to the applied offset at the current measurement time point; and
If the applied offset at the current measurement time point is smaller than the applied offset at the previous measurement time point, measuring the hydrogen concentration according to the applied offset at the previous measurement time point.
Measuring method of a hydrogen gas sensor device comprising a.
According to claim 1,
Correcting the applied offset with the reference limit if the offset to be applied during measurement is out of a predetermined reference limit
Measuring method of a hydrogen gas sensor device comprising a.
According to claim 2,
In the step of correcting the applied offset with the reference limit, correcting the applied offset with the reference limit is counted;
A method of measuring a hydrogen gas sensor device for notifying the outside when the counted value reaches a predetermined reference number.
According to claim 1,
In the step of measuring the hydrogen concentration according to the applied offset at the previous measurement time point, it is counted that the applied offset at the previous measurement time point is reflected,
A method of measuring a hydrogen gas sensor device for notifying the outside when the counted value reaches a predetermined reference number.
a temperature sensor to measure temperature;
Humidity sensor for measuring humidity;
A hydrogen sensor for measuring hydrogen gas concentration by thermal conduction;
a correction calculation unit which calculates a corrected hydrogen gas concentration by performing correction according to the measured value of the temperature sensor and the measured value of the humidity sensor with respect to the measured value of the concentration of the hydrogen sensor; and
After power is applied, an offset calculation unit that calculates the final hydrogen gas concentration by applying the first measured value of the hydrogen concentration to the corrected hydrogen gas concentration as an applied offset, and records the applied offset in a non-volatile memory
Including,
In order to apply temperature and humidity compensation for durability deterioration or VOC poisoning deterioration, the offset calculation unit,
Comparing a corrected hydrogen gas concentration value initially calculated after power is applied to the hydrogen gas sensor device with a predetermined reference value;
If the first calculated concentration value is less than a predetermined reference value, storing it as an applied offset at the current measurement time point;
Comparing a pre-stored applied offset at a previous measurement time point with an applied offset at a current measurement time point;
If the applied offset at the current measurement time point is greater than the applied offset at the previous measurement time point, measuring the hydrogen concentration according to the applied offset at the current measurement time point; and
If the applied offset at the current measurement time point is smaller than the applied offset at the previous measurement time point, measuring the hydrogen concentration according to the applied offset at the previous measurement time point.
A hydrogen gas sensor device with relative humidity compensation that performs
delete According to claim 5,
The offset calculation unit,
Correcting the applied offset with the reference limit if the offset to be applied during measurement is out of a predetermined reference limit
A hydrogen gas sensor device with relative humidity compensation applied to further perform.
According to claim 7,
The above standard limit is
A hydrogen gas sensor device with relative humidity compensation applied, a value selected in consideration of product variation within the range of -0.1% to -0.5%.

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