Wireless temperature measurement method and wireless temperature measurement sensor

Abstract

The present invention relates to the field of intelligent sensor technology, and specifically to a wireless temperature measurement method and a wireless temperature measurement sensor. The method obtains temperature data measured by the wireless temperature measurement sensor, current data of the power supply circuit, and voltage data across a thermistor during the measurement process of the wireless temperature measurement sensor; analyzes the temperature data, current data, and voltage data to determine the self-heating effect expression degree of the temperature value at each measurement moment during the measurement process, and then determines the self-heating effect temperature-flow proportional coefficient. Based on the self-heating effect expression degree, the self-heating effect temperature-flow proportional coefficient, and the current data, the temperature data is corrected to obtain corrected temperature data of the measurement process. The present invention effectively improves the accuracy of temperature measurement by correcting the temperature deviation caused by the self-heating effect of the wireless temperature measurement sensor.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent sensors, and in particular to a wireless temperature measurement method and a wireless temperature measurement sensor. Background Art

[0002] With the rapid development of industrial automation and intelligentization, the variety of power equipment is increasing, and high-precision equipment is also increasing. The requirements for real-time, accurate, and flexible temperature monitoring are constantly increasing. Traditional wired temperature measurement methods are limited by wiring complexity and environmental adaptability, making them difficult to meet the needs of special scenarios. Wireless temperature measurement technology collects temperature data through wireless sensors and transmits it to the receiving terminal, avoiding wiring restrictions. It has the advantages of easy installation, low cost, and strong adaptability. Wireless temperature sensors are typically based on technologies such as thermistors and combined with wireless communication modules (such as Bluetooth, Wi-Fi, and ZigBee) to achieve data transmission.

[0003] In existing wireless temperature measurement methods, thermistors' resistance changes with external temperatures and Ohm's law are used to convert temperature changes into voltage changes across the thermistor. The temperature is then calculated based on the relationship between voltage and temperature. However, the self-heating effect of wireless temperature sensors can cause temperature deviations in the measured temperature. This is because during operation, the sensor's temperature rises due to internal current flow or resistor heat generation, causing the sensor's temperature to exceed the ambient temperature. This is particularly noticeable in high-current or low-heat-dissipation environments, potentially leading to persistently high measured values. This affects the accuracy of temperature measurements and makes it impossible to meet the temperature measurement requirements of mechanical equipment with high temperature precision, such as transformer contacts. Summary of the Invention

[0004] In order to solve the above technical problems, the purpose of the present invention is to provide a wireless temperature measurement method and a wireless temperature measurement sensor. The technical solutions adopted are as follows:

[0005] In a first aspect, the present invention provides a wireless temperature measurement method, comprising the following steps:

[0006] Obtain temperature data measured by the wireless temperature sensor, current data of the power supply circuit during the measurement process of the wireless temperature sensor, and voltage data across the sensor thermistor;

[0007] According to the relationship between the changing trends of temperature data and voltage data, as well as the local changes of temperature data, the self-heating effect expression degree of the temperature value at each measuring moment in the measurement process is determined;

[0008] Determining target measurement moments during the measurement process based on the self-heating effect performance degree, and determining the self-heating effect temperature-current proportionality coefficient based on the correlation between the self-heating effect performance degree and the current data at each target measurement moment;

[0009] The temperature data is corrected according to the self-heating effect performance, the self-heating effect temperature-current proportional coefficient and the current data to obtain the corrected temperature data of the measurement process.

[0010] In conjunction with the first aspect above, in some possible implementations, determining the self-heating effect performance of the temperature value at each measurement moment during the measurement process includes:

[0011] Analyze the relationship between the changing trends of temperature data and voltage data to determine the temperature deviation at each measurement moment during the measurement process;

[0012] Analyze the local fluctuation of temperature data and determine the background interference level at each measurement moment during the measurement process;

[0013] The self-heating effect performance of the temperature value at each measurement moment in the measurement process is determined based on the background interference degree at each measurement moment in the measurement process and the temperature deviation degree of all measurement moments within the neighborhood time range of each measurement moment.

[0014] In conjunction with the first aspect above, in some possible implementations, determining the temperature deviation at each measurement moment during the measurement process includes:

[0015] determining a first temperature-pressure variation relationship index between all adjacent measurement moments during the measurement process based on a difference between a first ratio of the voltage value to the temperature value at a later measurement moment and a second ratio of the voltage value to the temperature value at a previous measurement moment;

[0016] determining, between all two adjacent measurement moments within a neighborhood time range of each measurement moment in the measurement process, a second temperature-pressure variation relationship indicator at each measurement moment in the measurement process based on a difference between a third ratio of the voltage value to the temperature value at the latter measurement moment and a fourth ratio of the voltage value to the temperature value at the previous measurement moment;

[0017] The temperature deviation degree at each moment in the measurement process is determined according to the difference between the second temperature-pressure change relationship index and the first temperature-pressure change relationship index.

[0018] In conjunction with the first aspect above, in some possible implementations, a process of determining the first temperature-pressure change relationship index and the second temperature-pressure change relationship index includes:

[0019] determining an absolute value of a difference between the first ratio and the second ratio to obtain a first ratio difference;

[0020] Performing negative correlation normalization processing on the mean of all first ratio differences between all two adjacent measurement moments during the measurement process to obtain a first temperature-pressure change relationship index;

[0021] determining an absolute value of a difference between the third ratio and the fourth ratio to obtain a second ratio difference;

[0022] The negative correlation normalization processing is performed on the mean of all second ratio differences between all two adjacent measurement moments within the neighborhood time range of each measurement moment in the measurement process to obtain the second temperature-pressure change relationship index.

[0023] In conjunction with the first aspect above, in some possible implementations, determining the background interference level at each measurement moment during the measurement process includes:

[0024] Determine the temperature mean and temperature variance of the temperature values ​​of all measurement moments within a neighborhood time range of each measurement moment during the measurement process;

[0025] The background interference degree at each measurement moment in the measurement process is determined by determining the difference between the temperature value at each measurement moment in the measurement process and the temperature mean value, as well as the temperature variance.

[0026] In conjunction with the first aspect above, in some possible implementations, determining the self-heating effect performance of the temperature value at each measurement moment during the measurement process includes:

[0027] Determine the average temperature deviation of all temperature deviations between two adjacent measurement moments within a neighborhood time range of each measurement moment during the measurement process;

[0028] Perform negative correlation normalization processing on the background interference degree to obtain the processing result;

[0029] The product of the average temperature deviation at each measuring moment in the measurement process and the processing result is determined, thereby obtaining the self-heating effect expression degree of the temperature value at each measuring moment in the measurement process.

[0030] In conjunction with the first aspect above, in some possible implementations, determining each target measurement moment in the measurement process according to the self-heating effect manifestation degree includes:

[0031] The self-heating effect performance degree at each measurement moment in the measurement process is compared with a set threshold, and the measurement moment in the measurement process where the self-heating effect performance degree is greater than the set threshold is used as the target measurement moment in the measurement process.

[0032] In conjunction with the first aspect above, in some possible implementations, determining the self-heating effect temperature-flow proportional coefficient includes:

[0033] Determine a fifth ratio of a first difference value of two self-heating effect manifestations to a second difference value of two current values ​​at each adjacent two target measurement moments during the measurement process to obtain a sub-self-heating effect temperature-current proportional coefficient;

[0034] The self-heating effect temperature flow proportional coefficient is determined according to the overall distribution level of the sub-self-heating effect temperature flow proportional coefficient corresponding to all two adjacent target measurement moments during the measurement process.

[0035] In conjunction with the first aspect above, in some possible implementations, the temperature data is corrected based on the current data and the temperature-flow proportional coefficient of the self-heating effect to obtain the corrected temperature data of the measurement process, including:

[0036] Based on the temperature value and self-heating effect performance at each target measurement moment, as well as the temperature-current proportional coefficient of the self-heating effect and the average current value of all measurement moments during the measurement process;

[0037] Determine the difference between the temperature value at each target measurement moment and the self-heating effect temperature deviation value to obtain a corrected temperature value at each target measurement moment;

[0038] The corrected temperature value at each target measurement moment and the temperature data at other measurement moments except for each target measurement moment during the measurement process together constitute the corrected temperature data of the measurement process.

[0039] In a second aspect, the present invention also provides a wireless temperature measurement sensor, which includes a wireless temperature measurement sensor body, a microprocessor installed in the wireless temperature measurement sensor body, a current sensor installed in the power supply circuit of the wireless temperature measurement sensor body, and a voltage sensor installed at both ends of the thermistor of the wireless temperature measurement sensor body. The microprocessor is communicatively connected to the current sensor and the voltage sensor, and a computer program is stored in the microprocessor. The microprocessor executes the computer program to implement the above-mentioned first aspect or a wireless temperature measurement method in any possible implementation method of the first aspect.

[0040] In a third aspect, the present invention further provides a wireless temperature measurement system, comprising a memory and a processor. The memory is configured to store executable program code, and the processor is configured to retrieve and execute the executable program code from the memory, so that the system performs a wireless temperature measurement method according to the first aspect or any possible implementation of the first aspect.

[0041] In a fourth aspect, the present invention also provides a computer program product, which includes: computer program code, which, when running on a computer, enables the computer to execute a wireless temperature measurement method in the above-mentioned first aspect or any possible implementation of the first aspect.

[0042] In a fifth aspect, the present invention also provides a computer-readable storage medium, which stores a computer program code. When the computer program code runs on a computer, the computer executes a wireless temperature measurement method in the above-mentioned first aspect or any possible implementation of the first aspect.

[0043] The present invention has the following beneficial effects: the present invention obtains the temperature data measured by the wireless temperature measuring sensor and the current data of the power supply circuit and the voltage data of the thermistor of the sensor during the measurement process of the wireless temperature measuring sensor; since the voltage of the thermistor in the wireless temperature measuring sensor changes according to the expected law as the temperature changes under normal working conditions, when the change relationship between the temperature data collected by the wireless temperature measuring sensor and the voltage data of the thermistor does not conform to the expected law, it means that the temperature data collected by the wireless temperature measuring sensor has an abnormal deviation. At the same time, when the abnormal deviation of the temperature data collected by the wireless temperature measuring sensor is caused by the self-heating effect of the sensor, the local fluctuation of the temperature data is often small and presents a more regular change. Therefore, according to the relationship between the change trends of the temperature data and the voltage data, and the local changes in temperature data, determine the self-heating effect expression degree of the temperature value at each measurement moment in the measurement process, the self-heating effect expression degree reflects the degree to which the temperature deviation of the temperature data is caused by the interference of the self-heating effect of the sensor; according to the self-heating effect expression degree, determine each target measurement moment in the measurement process, the temperature deviation caused by the self-heating effect of the sensor and the current show a certain correlation, according to the change correlation between the self-heating effect expression degree and the current data at each target measurement moment, determine the self-heating effect temperature flow proportional coefficient, the self-heating effect temperature flow proportional coefficient reflects the sensitivity of the temperature deviation caused by the self-heating effect to the current change; finally, according to the self-heating effect expression degree, the self-heating effect temperature flow proportional coefficient and the current data, the temperature data is corrected to obtain the corrected temperature data of the measurement process. The present invention corrects the temperature data measured by the sensor according to the data change characteristics caused by the self-heating effect of the wireless temperature measuring sensor to eliminate the temperature deviation caused by the self-heating effect, thereby obtaining the corrected temperature data, which effectively improves the accuracy of the temperature measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0045] Figure 1 This is a flowchart of a wireless temperature measurement method according to an embodiment of the present invention;

[0046] Figure 2 This is a schematic structural diagram of a wireless temperature measurement sensor according to an embodiment of the present invention;

[0047] Figure 3 The figure is a structural diagram of a wireless temperature measurement system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to clearly illustrate the technical features of this solution, the present invention is described in detail below through specific implementation methods in conjunction with the accompanying drawings.

[0049] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0050] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0051] As used herein, the term "including" and its variations are open-ended, i.e., "including but not limited to." The term "based on" means "based, at least in part, on." The term "one embodiment" means "at least one embodiment," the term "another embodiment" means "at least one additional embodiment," and the term "some embodiments" means "at least some embodiments." Other terms are defined in the following description.

[0052] It should be noted that the concepts of "first" and "second" mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0053] Although operations or steps are described in a particular order in the drawings in the embodiments of the present invention, this should not be understood as requiring that these operations or steps be performed in the particular order shown or in a serial order, or that all of the operations or steps shown be performed to obtain a desired result. In the embodiments of the present invention, these operations or steps may be performed serially; they may also be performed in parallel; or a portion of these operations or steps may be performed.

[0054] At the same time, it is understood that the data involved in the technical solutions of the present invention (including but not limited to the data itself, the acquisition or use of the data) shall comply with the requirements of relevant laws, regulations and relevant provisions. Unless otherwise defined, all technical and scientific terms used in this invention have the same meanings as those commonly understood by those skilled in the art to which this invention belongs, and all parameters or indicators in the formulas involved in this invention are normalized values ​​to eliminate the influence of dimensions.

[0055] In order to solve the problem in the prior art of reduced temperature measurement accuracy due to the self-heating effect of wireless temperature sensors, embodiments of the present invention provide a wireless temperature measurement method and a wireless temperature measurement sensor. By compensating for the temperature deviation caused by the self-heating effect of the wireless temperature measurement sensor, more accurate wireless temperature measurement data is obtained, effectively improving the accuracy of temperature measurement by the wireless temperature measurement sensor.

[0056] A wireless temperature measurement method and a wireless temperature measurement sensor provided by an embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

[0057] Figure 1 FIG. 1 shows a basic flow diagram of a wireless temperature measurement method provided by an embodiment of the present invention. Figure 1 As shown, the method specifically includes the following steps:

[0058] Step S100: Acquire temperature data measured by the wireless temperature measurement sensor, current data of the power supply circuit during the measurement process of the wireless temperature measurement sensor, and voltage data across the sensor thermistor.

[0059] Specifically, with the continuous improvement of science and technology, the types of power equipment are becoming more and more diverse, there are more and more high-precision equipment, and the temperature requirements are becoming higher and higher. Different temperatures have a great impact on the equipment. For example, transformer contacts require wireless temperature measurement methods to achieve real-time temperature monitoring of the equipment.

[0060] Since wireless temperature sensors typically measure temperature by passing current through their thermistors, this process generates heat, causing the sensor's temperature to rise. This rise is unrelated to the actual temperature change of the device being monitored by the sensor, but rather is caused by the self-heating effect generated by the current and resistance within the sensor. Therefore, identifying how the self-heating effect of wireless temperature sensors leads to temperature measurement errors, analyzing its impact on temperature measurement, and reducing this error can effectively improve the accuracy of temperature measurement data.

[0061] Therefore, to analyze the impact of the self-heating effect of wireless temperature sensors on temperature measurement, a current sensor is installed in the existing wireless temperature sensor's power supply circuit, for example, at the power input terminal, to monitor the sensor's real-time current consumption during operation. A voltage sensor is also installed across the sensor's thermistor to monitor voltage changes during operation. The current and voltage sensors acquire data at a set sampling frequency (e.g., 10 Hz) to capture dynamic current and voltage changes during sensor operation. The collected current and voltage signals are converted into digital data via an analog-to-digital converter (ADC). The temperature data measured by the existing wireless temperature sensor, along with the converted current and voltage data, are transmitted to a microprocessor (e.g., an STM32). At the same time, a timestamp is used to record the sampling time of each data value in the three data types, thereby obtaining the measurement time of the temperature, current, and voltage data. A microprocessor (such as an STM32) is then used to preprocess the temperature, current, and voltage data. For example, a low-pass filter (such as a moving average filter) is used to filter the data to remove high-frequency noise, missing values ​​are filled by interpolation, and then the current, voltage, and temperature data are normalized. The normalization method can be reasonably selected as needed, for example, the maximum and minimum value normalization method can be used for normalization.

[0062] Using this method, the wireless temperature sensor can obtain temperature data during each measurement, as well as current data from the power supply circuit and voltage data across the sensor's thermistor. This data, along with the measurement moments corresponding to each value, can be used to obtain the temperature, current, and voltage data. The microprocessor then analyzes this temperature, current, and voltage data and, based on the self-heating characteristics of the wireless temperature sensor, corrects the collected temperature data to eliminate temperature deviations caused by this effect, ultimately generating accurate corrected temperature data.

[0063] Step S200: determining the self-heating effect expression degree of the temperature value at each measurement moment during the measurement process according to the relationship between the change trends of the temperature data and the voltage data, and the local change of the temperature data.

[0064] Specifically, during wireless temperature measurement using a wireless temperature sensor, under normal operating conditions, the voltage and resistance of the thermistor in the sensor will change in a predictable pattern with temperature. This is determined by the sensor's design principles and exhibits a fixed pattern under specific conditions. By comparing the real-time voltage and temperature data collected with the sensor's expected normal variation, if the real-time data changes do not conform to expectations, such as when the temperature change does not match the voltage change, it indicates that the real-time temperature data collected by the sensor has an abnormal deviation. Furthermore, abnormal deviations in the real-time temperature data collected by the wireless temperature sensor during wireless temperature measurement may be caused by external environmental factors (such as electromagnetic interference, changes in ambient temperature and humidity), or by self-heating caused by heat generated by the current flowing within the sensor. These two different sources lead to different patterns of temperature data deviation. Temperature deviations caused by external environmental factors are often chaotic and fluctuate widely, while self-heating is always related to the current passing through the sensor, with smaller local fluctuations and more regular variations.

[0065] Therefore, based on the relationship between the changing trends of temperature data and voltage data, the abnormal deviation of the real-time temperature data collected by the wireless temperature measurement sensor can be analyzed. At the same time, combined with the local changes in the real-time temperature data collected by the wireless temperature measurement sensor, it is analyzed whether the abnormal deviation is caused by the interference of the self-heating effect of the sensor itself, so as to determine the self-heating effect performance of the real-time temperature data collected by the wireless temperature measurement sensor. The self-heating effect performance reflects the extent to which the temperature deviation in the temperature data is caused by the interference of the self-heating effect of the sensor.

[0066] Furthermore, the above-mentioned steps of determining the self-heating effect expression degree of the temperature value at each measurement moment during the measurement process include:

[0067] Analyze the relationship between the changing trends of temperature data and voltage data to determine the temperature deviation at each measurement moment during the measurement process;

[0068] Analyze the local fluctuation of temperature data and determine the background interference level at each measurement moment during the measurement process;

[0069] The self-heating effect performance of the temperature value at each measurement moment in the measurement process is determined based on the background interference degree at each measurement moment in the measurement process and the temperature deviation degree of all measurement moments within the neighborhood time range of each measurement moment.

[0070] Specifically, on the one hand, the wireless temperature sensor uses a thermistor to measure temperature, and uses the characteristic that different external temperatures of the sensor lead to different resistance values ​​and Ohm's theorem to convert temperature changes into changes in voltage across the resistor. Therefore, based on the relationship between the overall change trends of temperature data and voltage data, the temperature-pressure change relationship index under normal circumstances can be determined to reflect the change relationship between temperature data and voltage data under normal circumstances; at the same time, based on the relationship between the change trends of temperature data and voltage data in a local time period, the temperature-pressure change relationship index of the temperature value specific to each measurement moment in the temperature data can be determined, and the temperature-pressure change relationship index is compared with the temperature-pressure change relationship index under normal circumstances, so that the temperature deviation of the temperature value at each measurement moment can be determined.

[0071] Furthermore, the above-mentioned determination of the temperature deviation at each moment in the measurement process includes: determining a first temperature-pressure change relationship index between all adjacent measurement moments in the measurement process according to the difference between a first ratio of the voltage value to the temperature value at the latter measurement moment and a second ratio of the voltage value to the temperature value at the previous measurement moment; determining a second temperature-pressure change relationship index at each measurement moment in the measurement process according to the difference between a third ratio of the voltage value to the temperature value at the latter measurement moment and a fourth ratio of the voltage value to the temperature value at the previous measurement moment between all adjacent measurement moments in the neighborhood time range of each measurement moment in the measurement process; and determining the temperature deviation at each moment in the measurement process according to the difference between the second temperature-pressure change relationship index and the first temperature-pressure change relationship index.

[0072] In some possible implementations, the first temperature-pressure change relationship index is determined according to the following formula:

[0073]

[0074] Where: G represents the first temperature-pressure change relationship index; N represents the total number of measurement moments during the measurement process of the wireless temperature sensor; E n and E n+1 They represent the voltage values ​​at the nth and n+1th measurement moments during the measurement process of the wireless temperature sensor; W n and W n+1 They represent the temperature values ​​at the nth and n+1th measurement moments during the measurement process of the wireless temperature sensor; exp represents an exponential function with a natural constant as the base.

[0075] In the above formula, This value represents the average difference in the ratio of the voltage to the temperature between all two adjacent measurement moments during the measurement process of the wireless temperature sensor. This ratio difference average is used to characterize the corresponding change relationship between the voltage and temperature data under normal circumstances. The smaller the average difference, the more consistent the corresponding changes in the voltage and temperature data.

[0076] When a wireless temperature sensor is measuring temperature wirelessly, heat is generated by the resistance when current passes through the sensor. This causes the internal temperature of the sensor to often be higher than the actual temperature of the device being measured due to the heating effect of the current, resulting in a self-heating effect that causes temperature deviation. The self-heating effect of the wireless temperature sensor increases the internal temperature of the sensor, thereby affecting the sensor's resistance and voltage response, changing the original corresponding change relationship between voltage and temperature. The resistance change caused by the external environment is different from the resistance change caused by the internal current, and its corresponding relationship with voltage will also change. Based on the corresponding change relationship between the voltage and temperature data of the wireless temperature sensor, combined with the corresponding change relationship between the locally obtained voltage and temperature, the temperature deviation can be compared and obtained.

[0077] Therefore, for each measurement moment during the measurement process, the neighborhood time range of the measurement moment is obtained. For example, the measurement moment and the nine measurement moments in its left and right neighborhoods can be used as the neighborhood time range of the measurement moment. Based on the voltage and temperature values ​​of all measurement moments in the neighborhood time range, the second temperature-pressure change relationship index can be determined in the same manner as the first temperature-pressure change relationship index described above. The second temperature-pressure change relationship index can be compared with the first temperature-pressure change relationship index to determine the temperature deviation corresponding to the measurement moment.

[0078] In some possible implementations, the temperature deviation at each moment in the measurement process is determined by the following formula:

[0079] T i =|G i -G|;

[0080] Where: T i Indicates the temperature deviation at the i-th measurement moment during the measurement process; G i represents the second temperature-pressure change relationship index at the i-th measurement moment in the measurement process; G represents the first temperature-pressure change relationship index.

[0081] In the above formula, |G i -G| reflects the difference between the corresponding change relationship between the voltage and temperature data of the wireless temperature sensor at the i-th measurement moment during the measurement process and the corresponding change relationship between the voltage and temperature data under normal circumstances. The larger the difference value, the higher the degree of temperature deviation caused by the interference to the temperature sensor at this time.

[0082] On the other hand, in order to determine whether the temperature deviation of the wireless temperature sensor is caused by the influence of the self-heating effect of the wireless temperature sensor on the temperature measurement, rather than the influence of external environmental factors (such as electromagnetic interference, changes in ambient temperature and humidity, etc.) in which the sensor is located, the local changes in the temperature data are analyzed to determine the background interference degree of the temperature data, which is used to reflect the extent to which the temperature deviation of the sensor is caused by the influence of external environmental factors. When the local change fluctuation of the temperature data is greater, it means that the degree to which the temperature deviation of the sensor is caused by the influence of external environmental factors is higher, and the degree to which it is caused by the influence of non-self-heating effect on the temperature measurement is lower.

[0083] Furthermore, the above-mentioned steps of determining the background interference level at each moment in the measurement process include:

[0084] Determine the temperature mean and temperature variance of the temperature values ​​of all measurement moments within a neighborhood time range of each measurement moment during the measurement process;

[0085] The background interference degree at each measurement moment in the measurement process is determined by determining the difference between the temperature value at each measurement moment in the measurement process and the temperature mean value, as well as the temperature variance.

[0086] In some possible implementations, the background interference level at each moment in the measurement process is determined by the following formula:

[0087]

[0088] Where: B i Indicates the background interference degree at the i-th measurement moment during the measurement process; W i Indicates the temperature value at the i-th measurement moment during the measurement process; V represents the mean temperature of all the temperature values ​​at the time of measurement within the neighborhood time range of the i-th measurement time in the measurement process, that is, the average temperature value of all the temperature values ​​at the time of measurement. The neighborhood time range consists of the i-th measurement time and its left and right neighborhoods, a total of 9 measurement moments. i It represents the temperature variance of the temperature values ​​at all measurement moments within the neighborhood time range of the i-th measurement moment in the measurement process, that is, the variance of the temperature values ​​at all measurement moments.

[0089] In the above formula, It represents the difference between the temperature value at the i-th measurement moment and the mean temperature in the neighborhood time range of the i-th measurement moment during the measurement process. The temperature deviation caused by the self-heating effect has a certain pattern. When the difference is larger and the temperature variance in the neighborhood time range is larger, it means that the temperature fluctuation at the i-th measurement moment is larger, the degree to which the temperature deviation at the i-th measurement moment is caused by background interference is higher, and the corresponding background interference degree at the i-th measurement moment is greater.

[0090] Because temperature data deviations caused by the self-heating effect of wireless temperature sensors are often correlated with other sensor data, when the original data relationship is broken while retaining a certain regularity, that is, when the corresponding change relationship between local voltage and temperature data differs from the general corresponding change relationship between voltage and temperature data, but the local voltage data maintains a certain regularity, it indicates that the difference is more likely to be caused by interference from the sensor's self-heating effect. Therefore, the temperature deviation degree obtained from the change in the voltage-temperature relationship, combined with the background interference degree, can be used to obtain the self-heating effect representation of the temperature data.

[0091] Furthermore, the above-mentioned steps of determining the self-heating effect expression degree of the temperature value at each measurement moment during the measurement process include:

[0092] Determine the average temperature deviation of all temperature deviations between two adjacent measurement moments within a neighborhood time range of each measurement moment during the measurement process;

[0093] Perform negative correlation normalization processing on the background interference degree to obtain the processing result;

[0094] The product of the average temperature deviation at each measuring moment in the measurement process and the processing result is determined, thereby obtaining the self-heating effect expression degree of the temperature value at each measuring moment in the measurement process.

[0095] In some possible implementations, the self-heating effect performance at each measurement moment during the measurement process is determined by the following formula:

[0096]

[0097] Where: L i Indicates the self-heating effect performance at the i-th measurement moment during the measurement process; B represents the average temperature deviation of all measurement moments in the neighborhood time range of the i-th measurement moment during the measurement process. The neighborhood time range consists of the i-th measurement moment and its left and right neighborhoods, a total of 9 measurement moments; i represents the background interference degree at the i-th measurement moment in the measurement process; exp represents an exponential function with a natural constant as the base.

[0098] In the above formula, since the smaller the background interference value, the higher the degree to which the temperature difference is caused by the interference of the sensor's self-heating effect, an exponential function is used to perform negative correlation normalization on the background interference. The processing result is multiplied by the average temperature deviation to correct the average temperature deviation, thereby obtaining the self-heating effect performance at each moment in the measurement process.

[0099] Step S300: determining target measurement moments in the measurement process according to the self-heating effect performance, and determining a self-heating effect temperature-current proportionality coefficient according to a correlation between the self-heating effect performance and current data at each target measurement moment.

[0100] Specifically, during the operation of the wireless temperature sensor, the current generates heat through the resistor, causing the temperature of the sensor to rise, thereby making the measured temperature biased higher. The high-power sensor and wireless communication module will aggravate the self-heating effect, causing the internal temperature to exceed the temperature of the actual device to be measured. The temperature deviation caused by the self-heating effect shows a certain correlation with the current. According to the correlation between the self-heating effect performance of the temperature data at the corresponding moment and the change in the current data, the self-heating effect temperature-current proportional coefficient can be determined to reflect the correspondence between the deviation temperature caused by the self-heating effect of the sensor and the current data.

[0101] To analyze the correspondence between the deviation temperature and current data caused by the self-heating effect of the sensor, considering that the self-heating effect performance reflects the degree to which the temperature deviation in the temperature data is caused by the interference of the sensor self-heating effect, in some possible implementations, a set threshold can be pre-set, such as setting the set threshold value to 0.5. Then, the self-heating effect performance at each measurement moment during the measurement process is compared with the set threshold, and the measurement moment during the measurement process where the self-heating effect performance is greater than the set threshold is used as the target measurement moment during the measurement process. In some other possible implementations, an adaptive threshold can be determined using the Otsu threshold method based on the self-heating effect performance at all measurement moments during the measurement process, and the measurement moment during the measurement process where the self-heating effect performance is greater than the adaptive threshold is used as the target measurement moment.

[0102] Furthermore, the above-mentioned steps of determining the temperature-flow ratio coefficient of the self-heating effect according to the self-heating effect performance include:

[0103] Determine a fifth ratio of a first difference value of two self-heating effect manifestations to a second difference value of two current values ​​at each adjacent two target measurement moments during the measurement process to obtain a sub-self-heating effect temperature-current proportional coefficient;

[0104] The self-heating effect temperature flow proportional coefficient is determined according to the overall distribution level of the sub-self-heating effect temperature flow proportional coefficient corresponding to all two adjacent target measurement moments during the measurement process.

[0105] In some possible implementations, the self-heating effect temperature-flow proportional coefficient is determined by the following formula:

[0106]

[0107] Where: Q represents the temperature-current proportional coefficient of the self-heating effect, that is, the proportional coefficient of the temperature and current data measured when the self-heating effect of the wireless temperature sensor occurs; M represents the total number of all target measurement moments in the measurement process; L m and L m+1 They represent the self-heating effect performance at the mth and m+1th target measurement moments in the measurement process respectively; I m and I m+1 They represent the current values ​​at the mth and m+1th target measurement moments in the measurement process respectively.

[0108] In the above formula, the first difference value is obtained by calculating the absolute value of the difference between the two self-heating effect manifestations at each adjacent target measurement moment during the measurement process, and the second difference value is obtained by calculating the absolute value of the difference between the corresponding two current values. The ratio of the first difference value to the second difference value is used as a sub-self-heating effect temperature-flow proportional coefficient, and the average value of all sub-self-heating effect temperature-flow proportional coefficients is used as the self-heating effect temperature-flow proportional coefficient. The self-heating effect temperature-flow proportional coefficient reflects the sensitivity of the temperature deviation generated by the self-heating effect to the current change.

[0109] Step S400: Correcting the temperature data according to the current data and the temperature-current proportional coefficient of the self-heating effect to obtain corrected temperature data of the measurement process.

[0110] Specifically, when the wireless temperature sensor is affected by the current and produces a self-heating effect, there is a certain correlation between the current data and the temperature deviation. When there is a temperature deviation caused by the self-heating effect, the self-heating effect temperature-flow proportional coefficient reflects the sensitivity of the temperature deviation caused by the self-heating effect to the current change. At this time, based on the self-heating effect performance, the self-heating effect temperature-flow proportional coefficient and the current data, and combined with the temperature data, the self-heating effect deviation value of the temperature data can be determined. The self-heating effect deviation value is used for temperature compensation, and the measured temperature data is corrected to eliminate the deviation caused by the self-heating effect, so that more accurate temperature data can be obtained after correction.

[0111] Furthermore, the temperature data is corrected based on the self-heating effect performance, the self-heating effect temperature-flow ratio coefficient, and the current data to obtain the corrected temperature data of the measurement process. The implementation steps include:

[0112] Determine the self-heating effect temperature deviation value at each target measurement moment based on the temperature value and self-heating effect performance at each target measurement moment, as well as the self-heating effect temperature-current proportional coefficient and the average current value of all measurement moments during the measurement process;

[0113] Determine the difference between the temperature value at each target measurement moment and the self-heating effect temperature deviation value to obtain a corrected temperature value at each target measurement moment;

[0114] The corrected temperature value at each target measurement moment and the temperature data at other measurement moments except for each target measurement moment during the measurement process together constitute the corrected temperature data of the measurement process.

[0115] In some possible implementations, for a target measurement moment in a measurement process of a wireless temperature sensor, the self-heating effect temperature deviation value at each target measurement moment is determined by the following formula based on the temperature value and self-heating effect performance at each target measurement moment, as well as the self-heating effect temperature-current proportionality coefficient and the average current value of all measurement moments in the measurement process:

[0116]

[0117] In the formula: ΔW j W represents the temperature deviation value of the self-heating effect at the jth target measurement moment in the measurement process; j Indicates the temperature value at the jth target measurement moment in the measurement process; L j It represents the self-heating effect performance at the jth target measurement moment during the measurement process; Q represents the temperature-flow proportional coefficient of the self-heating effect; Indicates the average current value at all measurement moments during the measurement process.

[0118] In the above formula, the measured temperature will be higher than the actual temperature when affected by the self-heating effect. In order to calculate the self-heating effect temperature deviation value, the self-heating effect performance at the target measurement moment is calculated and compared with the fitted self-heating effect performance at all measurement moments in the measurement process obtained by the self-heating effect temperature flow proportional coefficient. When the self-heating effect performance at the target measurement moment is higher than the fitted self-heating effect performance level, it means that more heat is generated at the target moment, resulting in a higher temperature and a relatively high self-heating effect temperature deviation value. At the same time, the sensor relative temperature measurement value is offset. Combined with the influence weight of the temperature measurement value reflecting the temperature itself, that is, the self-heating effect is more obvious at high temperatures, the actual temperature deviation value is higher, and the final self-heating effect temperature deviation value can be determined from this.

[0119] Because the temperature data measured by the wireless temperature sensor is often higher than the actual temperature of the monitored device after being affected by the self-heating effect, the self-heating effect temperature deviation value at each target measurement time is obtained through the above analysis. The temperature data at each target measurement time is temperature compensated using the following formula to correct the measured value to eliminate the temperature deviation caused by the self-heating effect:

[0120] W′ j =W j -ΔW j ;

[0121] Where: W′ jW represents the corrected temperature value at the jth target measurement moment in the measurement process; j Indicates the temperature value at the jth target measurement moment in the measurement process; ΔW j Indicates the self-heating effect temperature deviation value at the jth target measurement moment in the measurement process.

[0122] According to the above method, the corrected temperature values ​​of all target measurement moments in the measurement process of the wireless temperature measurement sensor can be determined. These corrected temperature values ​​and the temperature data of other measurement moments except the target measurement moments in the measurement process together constitute the corrected temperature data of the measurement process.

[0123] After correcting the temperature data measured by the sensor and eliminating temperature deviations caused by sensor self-heating, the microprocessor within the wireless temperature sensor stores the corrected and accurate temperature data in a local database or transmits it to a cloud platform via a wireless communication module (such as Wi-Fi), ensuring the integrity and accuracy of the temperature measurement data. By using timestamps to record the specific sampling time of each temperature value in the temperature data, long-term data recording and tracking are performed, facilitating subsequent data analysis and management, ensuring that historical data can be retrieved at any time for review and comparison throughout the lifecycle of the monitored equipment. Furthermore, the corrected and accurate temperature data is displayed in real time through a user interface or monitoring platform, intuitively presenting the current status and historical trend information of the monitored equipment in the form of temperature curves or charts. This temperature data can be used to perform trend analysis on the temperature changes of the monitored equipment, thereby predicting the equipment's operating status and identifying potential problems. Combining real-time monitoring with trend analysis not only improves the efficiency of equipment management but also provides a scientific basis for predictive maintenance and decision support, significantly reducing the incidence of failures and maintenance costs.

[0124] Based on the same inventive concept, the embodiment of the present invention also provides a wireless temperature sensor, such as Figure 2 As shown, it includes a wireless temperature measurement sensor body, which refers to an existing wireless temperature measurement sensor. A microprocessor is installed in the wireless temperature measurement sensor body, a current sensor is installed in the power supply circuit of the wireless temperature measurement sensor body, and a voltage sensor is installed at both ends of the thermistor of the wireless temperature measurement sensor body. The microprocessor communicates with the current sensor and the voltage sensor. A computer program is stored in the microprocessor. When the microprocessor executes the computer program, any one of the wireless temperature measurement methods described above is implemented.

[0125] Based on the same inventive concept, the embodiment of the present invention also provides a wireless temperature measurement system, such as Figure 3As shown, the temperature measurement system includes: a memory 301, a processor 302, and a computer program 303 stored in the memory 301 and running on the processor 302, wherein when the processor 302 executes the computer program 303, the system can execute any one of the wireless temperature measurement methods introduced above.

[0126] In embodiments of the present invention, the system can be divided into functional modules based on the above-described method examples. For example, these modules can correspond to individual functional modules, or two or more functions can be integrated into a single processing module. The integrated modules can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and represents only a logical functional division. In actual implementation, other division methods may be used.

[0127] Based on the same inventive concept, an embodiment of the present invention further provides a computer program product, which includes: computer program code, which, when running on a computer, enables the computer to execute any one of the wireless temperature measurement methods described above.

[0128] Based on the same inventive concept, an embodiment of the present invention further provides a computer-readable storage medium, which stores computer program code. When the computer program code runs on a computer, the computer executes any one of the wireless temperature measurement methods described above.

[0129] It should be noted that the above-described embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the various embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A wireless temperature measurement method, characterized in that: The following steps are involved: Obtain temperature data measured by the wireless temperature sensor, current data of the power supply circuit during the measurement process of the wireless temperature sensor, and voltage data across the sensor thermistor; According to the relationship between the changing trends of temperature data and voltage data, as well as the local changes of temperature data, the self-heating effect expression degree of the temperature value at each measuring moment in the measurement process is determined; Determining target measurement moments during the measurement process based on the self-heating effect performance degree, and determining the self-heating effect temperature-current proportionality coefficient based on the correlation between the self-heating effect performance degree and the current data at each target measurement moment; Correcting the temperature data according to the self-heating effect performance, the self-heating effect temperature-flow ratio coefficient, and the current data to obtain corrected temperature data of the measurement process; Determine the self-heating effect representation of the temperature value at each measurement moment during the measurement process, including: Analyze the relationship between the changing trends of temperature data and voltage data to determine the temperature deviation at each measurement moment during the measurement process; Analyze the local fluctuation of temperature data and determine the background interference level at each measurement moment during the measurement process; Determine the self-heating effect performance of the temperature value at each measurement moment in the measurement process based on the background interference degree at each measurement moment and the temperature deviation degree of all measurement moments within the neighborhood time range of each measurement moment; Determine the temperature deviation at each measurement moment during the measurement process, including: determining a first temperature-pressure variation relationship index between all adjacent measurement moments during the measurement process based on a difference between a first ratio of the voltage value to the temperature value at a later measurement moment and a second ratio of the voltage value to the temperature value at a previous measurement moment; determining, between all two adjacent measurement moments within a neighborhood time range of each measurement moment in the measurement process, a second temperature-pressure variation relationship indicator at each measurement moment in the measurement process based on a difference between a third ratio of the voltage value to the temperature value at the latter measurement moment and a fourth ratio of the voltage value to the temperature value at the previous measurement moment; determining a temperature deviation at each moment during the measurement process according to a difference between the second temperature-pressure change relationship index and the first temperature-pressure change relationship index; Determine the background interference level at each measurement moment during the measurement process, including: Determine the temperature mean and temperature variance of the temperature values ​​of all measurement moments within a neighborhood time range of each measurement moment during the measurement process; Determining the background interference level at each measurement moment in the measurement process according to the difference between the temperature value at each measurement moment in the measurement process and the temperature mean, and the temperature variance; Determine the self-heating effect representation of the temperature value at each measurement moment during the measurement process, including: Determine the average temperature deviation of all temperature deviations between two adjacent measurement moments within a neighborhood time range of each measurement moment during the measurement process; Perform negative correlation normalization processing on the background interference degree to obtain the processing result; The product of the average temperature deviation at each measurement moment in the measurement process and the processing result is determined, thereby obtaining the self-heating effect performance of the temperature value at each measurement moment in the measurement process.

2. A wireless temperature measurement method according to claim 1, characterized in that: The process of determining the first temperature-pressure change relationship index and the second temperature-pressure change relationship index includes: determining an absolute value of a difference between the first ratio and the second ratio to obtain a first ratio difference; Performing negative correlation normalization processing on the mean of all first ratio differences between all two adjacent measurement moments during the measurement process to obtain a first temperature-pressure change relationship index; determining an absolute value of a difference between the third ratio and the fourth ratio to obtain a second ratio difference; The negative correlation normalization processing is performed on the mean of all second ratio differences between all two adjacent measurement moments within the neighborhood time range of each measurement moment in the measurement process to obtain the second temperature-pressure change relationship index.

3. A wireless temperature measurement method according to claim 1, characterized in that: Determining target measurement moments during the measurement process based on the self-heating effect manifestation degree includes: The self-heating effect performance degree at each measurement moment in the measurement process is compared with a set threshold, and the measurement moment in the measurement process where the self-heating effect performance degree is greater than the set threshold is used as the target measurement moment in the measurement process.

4. A wireless temperature measurement method according to claim 1, characterized in that: Determine the temperature-flow proportional coefficient of the self-heating effect, including: Determine a fifth ratio of a first difference value of two self-heating effect manifestations to a second difference value of two current values ​​at each adjacent two target measurement moments during the measurement process to obtain a sub-self-heating effect temperature-current proportional coefficient; The self-heating effect temperature flow proportional coefficient is determined according to the overall distribution level of the sub-self-heating effect temperature flow proportional coefficient corresponding to all two adjacent target measurement moments during the measurement process.

5. A wireless temperature measurement method according to claim 1, characterized in that: The temperature data is corrected based on the current data and the temperature-current proportional coefficient of the self-heating effect to obtain the corrected temperature data of the measurement process, including: Based on the temperature value and self-heating effect performance at each target measurement moment, as well as the temperature-current proportional coefficient of the self-heating effect and the average current value of all measurement moments during the measurement process; Determine the difference between the temperature value at each target measurement moment and the self-heating effect temperature deviation value to obtain a corrected temperature value at each target measurement moment; The corrected temperature value at each target measurement moment and the temperature data at other measurement moments except for each target measurement moment during the measurement process together constitute the corrected temperature data of the measurement process.

6. A wireless temperature sensor, characterized in that: The wireless temperature measurement sensor includes a wireless temperature measurement sensor body, a microprocessor is installed in the wireless temperature measurement sensor body, a current sensor is installed in the power supply circuit of the wireless temperature measurement sensor body, and voltage sensors are installed at both ends of the thermistor of the wireless temperature measurement sensor body. The microprocessor is communicatively connected to the current sensor and the voltage sensor. A computer program is stored in the microprocessor, and the microprocessor executes the computer program to implement a wireless temperature measurement method according to any one of claims 1 to 5.

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