A self-calibrating sensor device and method based on cold standby redundancy

Abstract

The application discloses a kind of self-calibration sensor devices based on cold backup redundancy, including power module, power module is connected with power timing switching module, sensor interface module, A / D conversion module, calibration module, signal output module and fault processing module;Wherein one sensor interface module is connected with main sensor, another sensor interface module is connected with backup sensor.The application adopts the precision self-calibration mode of main sensor and backup sensor, periodically enable backup sensor, compare the sampling value of main sensor and backup sensor by calibration module, judge whether the precision deviation of main sensor sampling value meets the precision requirement, if not satisfied, then use backup sensor and alarm to remind operation and maintenance personnel to replace, if normal, then continue to work using main sensor.The application can effectively solve the precision deviation of sensor with time in existing sensor application scene, so as to cause the use precision to not meet the requirement, need to replace the problem of inspection.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of sensors, in particular to a self-calibration sensor device and method based on cold standby redundancy. BACKGROUND

[0002] Although the conventional redundant sensor can improve the reliability of the sampling data, it cannot avoid the problem of sensor aging. Multiple sensors work at the same time, and the structure and sensing element of each sensor will change over time, resulting in output changes. Long-term use of the sensor causes aging, which further increases the precision deviation, affects its basic function, and causes the calculation results of the control system using the sensor to deviate, thereby causing irreversible consequences. In addition, if you want to troubleshoot the aging sensor, maintenance personnel need to individually check each sensor to locate the problem sensor, which is very cumbersome. In order to solve the above problems, researchers have adopted many ways of fault detection, such as the patent with the patent number CN109655090A and the patent name Redundant Sensor Fault Detection, which introduces "the fault detection method of the redundant sensor includes two oriented field sensors, one or both of the first field sensor and the second field sensor signals in the equivalent comparable sensor signal in the common orientation, and the fault field sensor is located by comparison. If the fault source is determined, a fault signal is generated and the fault sensor is indicated. If no fault source is determined, an output sensor signal is generated in response to the first sensor, the second sensor signal or the comparable sensor. The orientation of the difference between the comparable sensor signals can determine the fault source in the first field sensor and the second field sensor." Although this scheme can improve the data reliability of the sensor, when the same interference causes both working sensors to malfunction at the same time, it cannot exclude the fault. Due to long-term work, the precision deviation caused by sensor aging also affects the results of fault detection and is not easy to maintain, so the system constructed using this method has unstable factors.

[0003] For example, the patent with the patent number CN109829479A and the patent name Classifier Model Information Automatic Updating System for Sensor and Sensor Replacement Method, which introduces "the method for automatically updating sensor information includes two identical signal acquisition circuits, both of which include an A / D conversion module, a signal preprocessing module and a sensor socket array. The synchronization of signal transmission between the two A / D conversion modules is controlled by a synchronization signal. The sensor socket array can plug in multiple sensors, and the sensor installation does not require complex operation. It can be connected to the signal acquisition circuit through the pin by inserting the socket." This method and system can omit the process of testing new sensors and training the classifier model, so that non-professionals can replace it, simplifying the operation process and saving labor costs, but the disadvantage is that the two sensors work at the same time without considering the influence of sensor aging.

[0004] Therefore, it is urgent to develop a sensor calibration device to solve the precision deviation of the sensor over time in the existing sensor application scene, thereby causing the use precision to not meet the requirements and the need for inspection and replacement. SUMMARY

[0005] The purpose of the present application is to provide a self-calibration sensor device and method based on cold standby redundancy. The present application can effectively solve the precision deviation of the sensor over time in the existing sensor application scene, thereby causing the use precision to not meet the requirements and the need for inspection and replacement.

[0006] The technical solution of the present application is a self-calibration sensor device based on cold standby redundancy, comprising a power supply module, the power supply module is connected with a power supply timing switching module, the power supply timing switching module is connected in parallel with two sensor interface modules, the sensor interface module is connected with an A / D conversion module, the A / D conversion module is connected with a calibration module, the calibration module is respectively connected with a signal output module and a fault handling module, and the fault handling module is connected with the power supply timing switching module; one of the sensor interface modules is connected with a main sensor, and the other sensor interface module is connected with a standby sensor.

[0007] In the foregoing self-calibration sensor device based on cold standby redundancy, the power supply timing switching module can set a timing calibration time interval, trigger the power supply of the sensor interface module of the standby sensor after reaching the set time, wait for the processing result of the fault handling module, and process according to the processing result of the fault handling module; if the result of the fault handling module is to disconnect the standby, the power supply of the sensor interface module of the standby sensor is cut off; if the result of the fault handling module is to switch the main and standby, the power supply of the sensor interface module of the main sensor is cut off.

[0008] In the foregoing self-calibration sensor device based on cold standby redundancy, when the standby sensor is not enabled, the calibration module does not perform calibration work, and directly outputs the digital quantity converted by the A / D conversion module connected with the main sensor as the output of the signal output module; when the timing trigger of the power supply timing switching module triggers, the standby sensor is enabled, the digital quantity converted by the A / D conversion module connected with the main sensor and the digital quantity converted by the A / D conversion module connected with the standby sensor are compared and calibrated, if the deviation is less than the set error range, the calibration result "normal" is fed back to the fault handling module, if the deviation is greater than the set error range, the calibration result "fault" and the main sensor number are fed back to the fault handling module.

[0009] In the foregoing self-calibration sensor device based on cold backup redundancy, the fault handling module receives the feedback signal of the calibration module, if the feedback calibration result is "normal", the standby signal is disconnected to the power timing switching module; if the feedback calibration result is "fault", the signal of switching the main and standby is transmitted to the power timing switching module, and the fault light of the original main sensor is lit.

[0010] A self-calibration method based on cold backup redundancy adopts a main sensor and backup sensor precision self-calibration mode, periodically activates the backup sensor, compares the sampling values of the main sensor and the backup sensor through the calibration module, judges whether the precision deviation of the main sensor sampling value meets the precision requirement, if not, uses the backup sensor and alarms the operation and maintenance personnel to replace, if normal, continues to work using the main sensor.

[0011] In the foregoing self-calibration method based on cold backup redundancy, the specific self-calibration method is:

[0012] 1) Record the sampling deviation value of the main sensor and the backup sensor when first powered on as the initial deviation value P0 for periodic calibration;

[0013] 2) During periodic calibration, the backup sensor is powered on, the sampling values of the main sensor and the backup sensor are compared to obtain the deviation value Pn of the nth calibration; n , Pn-1 n and Pn-2 n-1 . n ;

[0014] 3) According to the deviation value offset, the state of the main sensor and the backup sensor is judged.

[0015] In the foregoing self-calibration method based on cold backup redundancy, the specific judgment process of step 3) is:

[0016] When conditions ① the fault determination increment value EV is greater than the deviation value offset ΔPn-1 n-2 , ΔPn-2 n-1 , ΔPn-3 n for three times in a row, condition ② the deviation value offset ΔPn-1 n-2 , ΔPn-2 n-1 , ΔPn-3 n for three times in a row is greater than or equal to 0 or less than or equal to 0, and condition ③ the deviation value Pn n of this calibration is greater than the main backup switching set deviation value SV, it is determined that the main sensor is slowly aging; the backup sensor is used as the main sensor, the original main sensor is powered off, and the fault maintenance light is lit to prompt the maintenance personnel to replace the original main sensor, after replacement, the fault maintenance light is eliminated, and the replaced sensor is used as the backup sensor and is powered off to wait for the next calibration;

[0017] When condition ③ is met, and only one of condition ① and condition ② is met or neither of them is met, it is determined that the device is malfunctioning;

[0018] In the remaining cases, it is determined that the device is working normally, and the standby sensor is powered off and waits for the next calibration.

[0019] In the foregoing self-calibration method based on cold standby redundancy, when it is determined that the main sensor is slowly aging, the standby sensor is used as the main sensor, the original main sensor is powered off, and a fault maintenance light is turned on to prompt a maintenance personnel to replace the original main sensor. After replacement, the fault maintenance light is eliminated, and the replaced sensor is used as the standby sensor and is powered off and waits for the next calibration.

[0020] In the foregoing self-calibration method based on cold standby redundancy, in step 3), fault determination is further performed. The specific manner of fault determination is as follows: the sampling values Pm n-3 , Pm n-2 , and Pm n-1 of the main sensor in the last three periodic calibrations are taken, and the maximum value and the minimum value of the three are taken as boundaries; if the sampling value Pm n of the main sensor and the sampling value Ps n of the standby sensor in the current periodic calibration are only one of them is within the boundary range, the one within the range is the normal sensor, and the one outside the range is the faulty sensor; if both of them are within or not within the boundary range, it is considered that the main sensor is malfunctioning.

[0021] Compared with the prior art, the application uses the standby sensor as a calibration source by the principle that the standby sensor does not work normally and only works at calibration time, avoids the failure of both sensors caused by instantaneous interference when the two sensors work simultaneously, and reduces the precision deviation of the standby sensor caused by long-term work (the standby sensor is only enabled at a timing trigger, the wear and tear of the standby sensor used as a calibration source for a long time is reduced, the accuracy and reliability of the sensor sampling result are ensured, and the error caused by simultaneous attenuation is avoided); in addition, since the standby sensor is basically in a non-working state, it can be directly plugged and replaced, and maintenance is facilitated. That is, the application can judge the precision of the sensor by using the precision self-calibration method of the main and standby sensors without additional design of a complex circuit, enable the standby sensor regularly, judge whether the precision deviation of the main sensor sampling value meets the precision requirement, use the standby sensor and alarm the operator to replace if the precision deviation does not meet the precision requirement, and continue to work using the main sensor if the precision deviation meets the precision requirement, thereby effectively solving the precision deviation of the traditional sensor caused by long-term use and aging. On this basis, the application is optimized in circuit structure, only one is normally powered on when the main and standby sensors are switched, and the other is in a power-off state, so that the sensor can be replaced without power-off, and daily maintenance or fault replacement is more convenient. In summary, the application can effectively solve the precision deviation of the sensor caused by time in the application scene of the existing sensor, so that the use precision does not meet the requirement and needs to be replaced by inspection. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a structural schematic diagram of the application;

[0023] Figure 2 is a sensor calibration fault processing flowchart.

[0024] The marks in the drawings are: 1-power module, 2-power timing switching module, 3-sensor interface module, 4-A / D conversion module, 5-calibration module, 6-signal output module, and 7-fault processing module. DETAILED DESCRIPTION

[0025] The application will be further described below in combination with the drawings and examples, but it is not used as the basis for limiting the application.

[0026] Example. A self-calibration method based on cold standby redundancy, comprising:

[0027] Two completely identical sensor elements are used to form a redundant structure, one as a main sensor and the other as a standby sensor;

[0028] The redundant structure only has the main sensor powered on and the standby sensor not powered on as a calibration source for periodic calibration in a cold standby state when working.

[0029] Upon initial power-on, the sampling deviation values ​​between the main sensor and the backup sensor are recorded as the initial deviation value P0 for periodic calibration.

[0030] During periodic calibration, the backup sensor is powered on, and the sampled values ​​from the main sensor and the backup sensor are compared to obtain the deviation value P for the nth calibration. n , will P n With P n-1 The offset ΔP of the deviation value is obtained by subtracting the values. n ;

[0031] When simultaneously satisfying ① the fault identification increment value EV is greater than the deviation value offset ΔP of three consecutive times... n-2 ΔP n-1 ΔP n ② The deviation value ΔP for three consecutive times n-2 ΔP n-1 ΔP n All values ​​are greater than or equal to 0 or all values ​​are less than or equal to 0; ③ The deviation value P of this calibration. n >When the set deviation value SV is set during the master / slave switchover. Since the backup sensor has been in a cold standby redundant state for a long time, its aging degree is necessarily less than that of the master sensor, and it is determined that the master sensor is slowly aging. The backup sensor is used as the master sensor, the original master sensor is powered off, and the fault indicator light illuminates, prompting the maintenance personnel to replace the original master sensor. After replacement, the fault indicator light goes out, and the replaced sensor becomes the backup sensor, powered off and waiting for the next calibration.

[0032] When condition ③ above is met, but only one of conditions ① and ② is met, or neither is met, the equipment is considered faulty. Since the comparison only involves the primary and backup sensors, and no third party is involved, it is impossible to determine the fault source between the primary and backup sensors. Therefore, a fault determination method is introduced here. The sampled value Pm of the primary sensor during the three most recent periodic calibrations is taken. n-3 Pm n-2 Pm n-1 Taking the maximum and minimum values ​​among the three as boundaries, the main sensor sampling value Pm for this periodic calibration is... n and backup sensor sample value Ps n If only one of them is within the boundary range, the one within the range is a normal sensor, and the one outside the range is a faulty sensor. If both are within or not within the boundary range, the main sensor is considered to be faulty. When the main sensor is faulty, the main / standby switching and fault alarm process described above is executed. If the standby sensor is faulty, there is no switching, and only the fault inspection light is lit.

[0033] All other situations are considered normal operation, and the backup sensor is powered off and awaits the next calibration.

[0034] A self-calibration sensor device based on cold backup redundancy, comprising:

[0035] The device needs to contain a power module to supply power to the rest of the internal modules of the self-calibration sensor device;

[0036] The device internally includes a timing module, two sensor interface modules, two A / D conversion modules, a calibration module, a fault handling module, and a signal output module.

[0037] A power switching module,

[0038] With timing function, can set timing calibration time interval, after reaching the set time trigger to enable the interface module power supply of the backup sensor, while waiting for the processing result of the fault handling module, and according to the processing result of the fault handling module to make processing, if the result of the fault handling module is to disconnect the backup, cut off the power supply of the backup sensor interface module, if the result of the fault handling module is to switch the main and backup, cut off the power supply of the main sensor interface module;

[0039] Sensor interface module,

[0040] Can access the sensor, convenient for sensor disassembly and maintenance;

[0041] A / D conversion module, characterized by:

[0042] Can convert the analog signal of the sensor into digital signal;

[0043] Calibration module, characterized by:

[0044] When the backup sensor is not enabled, do not calibrate, directly use the digital quantity converted by the A / D conversion module connected to the main sensor as the output of the signal output module. When the timing trigger of the power switching module, the backup sensor is enabled, compare and calibrate the digital quantity converted by the A / D conversion module connected to the main sensor and the digital quantity converted by the A / D conversion module connected to the backup sensor, if the deviation is less than the set error range, the calibration result "normal" is fed back to the fault handling module, if the deviation is greater than the set error range, the calibration result "fault" and the main sensor number are fed back to the fault handling module;

[0045] Fault handling module, characterized by:

[0046] Can receive the feedback signal of the calibration module, if the feedback calibration result is "normal", disconnect the backup signal to the power switching module, if the feedback calibration result is "fault", switch the main and backup signal to the power switching module, and light up the fault light of the original main sensor;

[0047] Signal output module, characterized by:

[0048] The sampling value of the main sensor can be outputted.

[0049] Cold backup redundancy: Cold backup redundancy refers to that in the redundancy structure, the backup device and the main device do not backup data in real time, and the backup device is in a non-working state for a long time, and is powered on regularly to compare and synchronize data with the main device.

[0050] A / D conversion: A / D conversion refers to converting an analog input signal (herein referred to as a signal received by a sensor probe) into a corresponding digital output.

[0051] Master-slave switching: Master-slave switching refers to that when a fault occurs, the backup device takes over the function of the working device, and the original working device becomes a backup device.

Claims

1. A self-calibration method based on cold-standby redundancy, characterized in that: The cold backup redundancy self-calibration is realized by using a cold backup redundancy based self-calibration sensor device, which comprises a power supply module (1), the power supply module (1) is connected with a power supply timing switch module (2), the power supply timing switch module (2) is connected in parallel with two sensor interface modules (3), the sensor interface modules (3) are connected with an A / D conversion module (4), the A / D conversion module (4) is connected with a calibration module (5), the calibration module (5) is connected with a signal output module (6) and a fault processing module (7) respectively, and the fault processing module (7) is connected with the power supply timing switch module (2); one of the sensor interface modules (3) is connected with a main sensor, and the other sensor interface module (3) is connected with a backup sensor. The self-calibration method is as follows: the main sensor and the backup sensor are periodically enabled, the sampling values of the main sensor and the backup sensor are compared by the calibration module, whether the precision deviation of the sampling value of the main sensor meets the precision requirement is judged, if not, the backup sensor is put into use and an alarm is given to remind the operation and maintenance personnel to replace, and if normal, the main sensor continues to work. The specific self-calibration method is as follows: 1) Record the sampling offset values of the primary and backup sensors at the first power-up as the initial offset values for periodic calibration ; 2) During periodic calibration, the backup sensor is powered on, and the sampled values ​​of the main sensor and the backup sensor are compared to obtain the deviation value of the first calibration. ,Will and The difference is used to obtain the deviation value offset. ; 3) the state of the main sensor and the backup sensor is judged according to the deviation value offset; The specific judgment process of step 3) is as follows: When the conditions ① and ② are satisfied simultaneously, the fault is determined to be the fault of the first fault determination increment value ; Condition 2: deviation value offset of three consecutive times are all greater than or equal to 0 or are all less than or equal to 0; Condition 3: deviation value of this calibration > master standby switching set deviation value , it is determined that the main sensor is slowly aging; the standby sensor is used as the main sensor, the original main sensor is powered off, and the fault maintenance light is turned on to prompt the maintenance personnel to replace the original main sensor; after replacement, the fault maintenance light is eliminated, and the replaced sensor is used as the standby sensor and is powered off to wait for the next calibration; When the condition ③ is met, and only one of the conditions ① and ② is met or neither of them is met, it is determined that the device is faulty; In other cases, it is determined that the device is working normally, and the backup sensor is powered off and waits for the next calibration; In step 3), fault judgment is also needed, and the specific way of fault judgment is: taking the sampling value of the main sensor at the last three periodic calibrations , taking the maximum and minimum of the three as the boundary; if the sampling value of the main sensor at this periodic calibration and the sampling value of the backup sensor are only one of them within the boundary range, then the one within the range is the normal sensor and the one outside the range is the fault sensor; if both are within or not within the boundary range, it is considered that the main sensor is faulty.

2. The self-calibration method based on cold backup redundancy according to claim 1, characterized in that, The power supply timing switch module can set the timing calibration time interval, and after reaching the set time, the power supply of the sensor interface module for enabling the backup sensor is triggered, and the processing result of the fault processing module is waited for, and the processing is made according to the processing result of the fault processing module; If the result of the fault processing module is to disconnect the backup, the power supply of the sensor interface module for the backup sensor is cut off; If the result of the fault processing module is to switch the main and backup, the power supply of the sensor interface module for the main sensor is cut off.

3. The self-calibration method based on cold standby redundancy according to claim 1, characterized in that, When the backup sensor is not enabled, the calibration module does not calibrate, and the digital quantity converted by the A / D conversion module connected with the main sensor is directly output as the output of the signal output module; when the timing trigger of the power supply timing switch module triggers, the backup sensor is enabled, the digital quantity converted by the A / D conversion module connected with the main sensor and the digital quantity converted by the A / D conversion module connected with the backup sensor are compared and calibrated, if the deviation is less than the set error range, the calibration result "normal" is fed back to the fault processing module, and if the deviation is greater than the set error range, the calibration result "fault" and the number of the main sensor are fed back to the fault processing module.

4. The self-calibration method based on cold backup redundancy according to claim 3, characterized in that, The fault processing module receives the feedback signal of the calibration module, if the feedback calibration result is "normal", the signal of disconnecting the backup is transmitted to the power supply timing switch module, if the feedback calibration result is "fault", the signal of switching the main and backup is transmitted to the power supply timing switch module, and the fault light of the original main sensor is lit.

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