Temperature controller contact resistor fault monitoring and positioning method and system

Abstract

The invention discloses a temperature controller contact resistance fault monitoring and positioning method and system, and belongs to the technical field of contact resistance testing. According to the method, the corresponding initial database is constructed according to the models of different temperature controllers; performing low-energy-consumption real-time monitoring on the contact resistance in the temperature controller by adopting a resistance fluctuation threshold value monitoring method in combination with the initial database; when the fluctuation of the contact resistor is monitored, the infrared thermal imaging module is started to accurately determine the position information and the fault degree of the contact resistor according to a relative temperature difference method in combination with a resistance threshold fluctuation value.

Description

Technical Field

[0001] The invention belongs to the technical field of contact resistance testing, and in particular relates to a method and system for monitoring and locating contact resistance faults of a temperature controller. Background Art

[0002] A thermostat is a mechanical device used to automatically adjust or maintain the temperature of equipment or the environment. It monitors temperature fluctuations and controls the system's operating status, ensuring the temperature remains stable within a set range. Thermostat contact resistance refers to the electrical resistance between the switch contacts inside the thermostat when they are closed. Abnormal changes in contact resistance during thermostat operation can affect the performance and lifespan of the device and may even create safety hazards.

[0003] Among the existing technologies for thermostat contact resistance fault monitoring, Chinese invention patent publication number CN119178935A discloses a thermostat contact resistance test and early warning method. This patent utilizes temperature sensors, current sensors, and voltage sensors to perform real-time monitoring of each contact resistance in the thermostat. This method requires multiple sensors to be arranged inside the thermostat, resulting in complex wiring arrangements. The greater the number of thermostat contact resistances, the higher the number of sensors required and the requirements, and the greater the amount of data required to process for real-time monitoring. This results in high energy consumption and costs, and limited versatility. Therefore, there is an urgent need for a more versatile technology that can perform low-energy, real-time fault location monitoring of thermostat contact resistance. Summary of the Invention

[0004] The purpose of the present invention can be achieved through the following technical solutions: In order to solve the above problems existing in the prior art, the present invention provides a method and system for monitoring and locating contact resistance faults of a thermostat.

[0005] A first aspect of the present disclosure provides a method for monitoring and locating a thermostat contact resistance fault, comprising the steps of: S1: Obtain the number of contact resistors, resistance value data, position data, and first temperature data corresponding to each contact resistor in the thermostat; obtain the position data of the infrared thermal imaging module; obtain the current data and voltage data of the thermostat in real time when it is working; and construct an initial thermostat database based on the above data; S2: performing noise reduction processing on the first temperature data and calculating the distance between the infrared thermal imaging module and each contact resistor, thereby performing temperature compensation processing on the first temperature data after the noise reduction processing; S3: Monitor the total resistance of the thermostat during operation based on the current and voltage data acquired in real time. Combined with the initial database, monitor abnormal fluctuations in contact resistance within the thermostat using the resistance fluctuation threshold monitoring method. S4: When it is detected that the resistance fluctuation value of the contact resistance in the temperature controller is greater than the resistance fluctuation threshold, the infrared thermal imaging module is activated; S5: The infrared thermal imaging module scans the contact resistance in the thermostat, collects the second temperature data of each contact resistor in the current thermostat and the third temperature data of the current environment, and performs noise reduction and temperature compensation processing on the second temperature data; S6: Based on the third temperature data and the first temperature data and the second temperature data after noise reduction and temperature compensation, a relative temperature difference method is used to determine the faulty contact resistance and the fault degree according to the relative temperature difference of each contact resistor, thereby determining first position information and first fault degree information of the faulty contact resistor; S7: Extract the first position information of all faulty contact resistors output in step S6, cluster the position coordinates based on a preset distance threshold, and generate at least one fault temperature rise area; if the number of contact resistors associated with a certain fault temperature rise area is 1, directly output the result in step S6; if the number of associations is greater than 1, retrieve the resistance data of each contact resistor in the area, perform resistance threshold fluctuation value determination, and output the second position information and second fault degree information of the final fault resistor.

[0006] Specifically, the current data and voltage data include: standard current data and standard voltage data when the thermostat is working normally, and working current data and working voltage data of the thermostat when working collected in real time by the current sensor and voltage sensor; the first temperature data is the standard temperature data of each contact resistor when working normally; the second temperature data is the abnormal temperature data of each contact resistor when abnormal fluctuations in contact resistance are monitored at time t; the third temperature data is the ambient temperature data when abnormal fluctuations in contact resistance are monitored at time t.

[0007] Specifically, the initial database is constructed according to the contact resistance distribution characteristics of different types of thermostats, and contact resistance fault monitoring and positioning are performed based on the constructed initial database.

[0008] Specifically, the noise reduction process adopts wavelet packet analysis method; The temperature compensation process includes calculating the error temperature caused by the infrared measurement distance and the deviation between the measured temperature and the actual temperature. Expressed as: , in, For infrared thermal imaging module and contact resistance distance; is the attenuation coefficient.

[0009] Specifically, the resistance fluctuation value Expressed as: , in, is the standard total resistance when the thermostat is working normally, is the total resistance of the thermostat when it works at time t, is the total contact resistance inside the thermostat.

[0010] Specifically, the relative temperature difference Expressed as: , in, is the first temperature data after noise reduction and temperature compensation; is the second temperature data after noise reduction and temperature compensation, and T is the third temperature data.

[0011] Specifically, step S7 includes the following steps: S71: Extracting first position information of all faulty contact resistors output in step S6, clustering the position coordinates based on a preset distance threshold, and generating at least one fault temperature rise area; S72: Determine the amount of contact resistance associated with the fault temperature rise area. When the number is equal to 1, the first position information and the first fault degree information of the fault contact resistance in step S6 are output; When the number is greater than 1, the resistance value data of each contact resistor contained in the corresponding position of the fault temperature rise area is retrieved, and the second position information and second fault degree information of the final fault contact resistance are output after fault judgment.

[0012] Specifically, the method of outputting the second position information and the second fault degree information of the final fault contact resistance after fault judgment comprises the following steps: S73: Calculating resistance threshold fluctuation values ​​of each fault contact resistance; S74: Compare the resistance threshold fluctuation value of each fault contact resistance with the monitored resistance fluctuation value Compare and obtain the fluctuation deviation value, and select the contact resistance corresponding to the minimum fluctuation deviation value is the final fault contact resistance; S75: Output the second position information and the second fault degree information of the final fault contact resistance.

[0013] Specifically, the resistance threshold fluctuation value of each fault contact resistance is as follows: a plurality of contact resistors are included in the fault temperature rise region, a contact resistance value corresponding to each contact resistor in the fault temperature rise region is obtained, a numerical range of three times the resistance of each contact resistor is recorded as a theoretical fault resistance fluctuation value, and a ratio of the theoretical fault resistance fluctuation value to the total contact resistance is recorded as the resistance threshold fluctuation value of the corresponding resistor; A second aspect of the present disclosure provides a thermostat contact resistance fault monitoring and locating system, which applies the thermostat contact resistance fault monitoring and locating method described above; A temperature controller contact resistance fault monitoring and positioning system specifically includes: a data acquisition module, a data preprocessing module, a contact resistance fluctuation monitoring module and an infrared thermal imaging fault positioning module; The data acquisition module is composed of a micro-ohmmeter, an infrared thermal imaging module, a current sensor, and a voltage sensor; it is used to obtain the number of contact resistors, resistance value data, position data, and temperature data corresponding to each contact resistor in the thermostat; obtain the position data of the infrared thermal imaging module; obtain the current data and voltage data when the thermostat is working; and construct an initial database of the thermostat based on the above data; The data preprocessing module is used to perform noise reduction and temperature compensation processing on the temperature data; and calculate the distance between the infrared thermal imaging module and each contact resistor based on the position data of each contact resistor and the position data of the infrared thermal imaging module; The contact resistance fluctuation monitoring module is used to monitor the total resistance of the thermostat during operation based on the current and voltage data collected in real time, and to monitor abnormal fluctuations in the contact resistance in the thermostat using a resistance fluctuation threshold monitoring method in combination with the initial database; The infrared thermal imaging fault location module is used to collect temperature data, determine the specific contact resistance and fault severity of the fault by using the relative temperature difference method combined with the resistance threshold fluctuation value, and output the location information of the fault resistance and the fault severity; The contact resistance fluctuation monitoring module is in a working state for a long time and is used to monitor in real time whether the contact resistance fluctuates abnormally; when no abnormal fluctuation of the contact resistance is detected, the infrared thermal imaging fault locating module is in a standby state; when abnormal fluctuation of the contact resistance is detected, the infrared thermal imaging fault locating module is in a working state.

[0014] The beneficial effects of the present invention are: This application can achieve the same contact resistance fault monitoring effect by building a corresponding initial database based on different models of thermostats, and has strong versatility.

[0015] The present application provides a contact resistance fluctuation monitoring module and adopts a resistance fluctuation threshold monitoring method to perform non-contact, long-term, low-energy consumption, real-time fault monitoring of the contact resistance in the temperature controller without the need for shutdown measurement.

[0016] The present application sets up an infrared thermal imaging fault location module to monitor and locate the faulty contact resistance based on the relative temperature difference method and determines the degree of the contact resistance fault based on the size of the temperature difference. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] To facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0018] Figure 1 A schematic diagram of the steps of a method for monitoring and locating a thermostat contact resistance fault provided by an embodiment of the present invention; Figure 2 A schematic diagram of the steps for determining a resistance threshold fluctuation value provided by an embodiment of the present invention; Figure 3 A schematic structural diagram of a temperature controller contact resistance fault monitoring and locating system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0020] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0021] In addition, the descriptions of "first", "second", etc. in the present invention are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0022] The present invention provides a method for monitoring and locating a temperature controller contact resistance fault. The method mainly performs contact resistance fault monitoring and locating in three steps: First, build the corresponding initial database according to the models of different thermostats to ensure universality; Secondly, the resistance fluctuation threshold monitoring method is used in combination with the initial database to conduct real-time monitoring of the contact resistance in the thermostat to ensure low energy consumption of real-time monitoring; Finally, when contact resistance fluctuations are detected, the infrared thermal imaging module is activated to determine the location information and fault degree of the contact resistance based on the relative temperature difference method and combined with the resistance threshold fluctuation value, thereby ensuring the accuracy of contact resistance fault monitoring.

[0023] Specifically, the following content describes in detail a method and system for monitoring and locating a temperature controller contact resistance fault: Example 1 See also Figure 1 The present invention provides a method for monitoring and locating a temperature controller contact resistance fault, comprising the steps of: S1: Obtain the number of contact resistors, resistance value data, position data, and temperature data corresponding to each contact resistor in the thermostat; obtain the position data of the infrared thermal imaging module; obtain the current data and voltage data when the thermostat is working; and construct the initial database of the thermostat based on the above data.

[0024] The number and position data of the contact resistors in the thermostat are obtained through the factory-set parameters of the thermostat. The position data of the contact resistors are represented by three-dimensional spatial coordinates. A contact resistance point set is constructed based on the number and position data. The i-th contact resistor in the thermostat is expressed as ( , , ), in addition, the position data of the infrared thermal imaging module is also expressed in three-dimensional space coordinates. The position coordinates of the infrared thermal imaging module are D0 ( , , ), the position coordinates of the contact resistor and the position coordinates of the infrared thermal imaging module use the same coordinate system; Contact resistance in thermostat The resistance value data is accurately measured by using a micro-ohmmeter, and the total resistance value of the contact resistance in the thermostat is calculated based on the measured resistance value. ; The temperature data includes: first temperature data : The temperature of each contact resistor in the thermostat when it is working normally; the second temperature data : When abnormal fluctuations in the thermostat contact resistance are detected at time t, the temperature of each contact resistor; the third temperature data : The ambient temperature when abnormal fluctuations in the thermostat contact resistance are detected at time t; The current data and voltage data of the thermostat when working specifically include: standard working current data and voltage data of the thermostat when working normally obtained based on the factory parameters of the thermostat, which are used to calculate the standard total resistance of the thermostat when working normally; and working current data and voltage data of the thermostat when working are collected in real time based on the current sensor and the voltage sensor, which are used to monitor the total resistance of the thermostat when working in real time.

[0025] Through step S1, a corresponding initial database can be constructed according to different types of thermostats, and the same contact resistance fault monitoring effect can be achieved based on the initial database.

[0026] S2: performing noise reduction processing on the first temperature data and calculating the distance between the infrared thermal imaging module and each contact resistor, thereby performing temperature compensation processing on the first temperature data after the noise reduction processing; Perform noise reduction on the collected temperature data: The temperature data that needs to be denoised is the first temperature data and the second temperature data .

[0027] As a preferred solution, the noise reduction processing method is: collecting the first temperature data and the second temperature data Wavelet packet analysis is used to remove the noise generated during the sampling process.

[0028] The principle of wavelet packet analysis in the temperature data noise reduction process is as follows: Measured temperature signal By the useful signal and noise signal Composition, the measured temperature signal Perform wavelet transform and use wavelet transform to decompose the signal into high-frequency and low-frequency parts; It is a Gaussian distributed noise signal, and its amplitude will continue to increase as the level of wavelet transform decreases. The temperature signal is degraded by wavelet transform, which increases the amplitude of the noise signal. Then, some high-frequency signals that are decomposed are removed to complete the noise reduction. The temperature signal with some high-frequency signals removed is reconstructed by wavelet using the reconstruction function to obtain the denoised temperature signal. .

[0029] As a preferred solution, the specific process of the wavelet packet analysis method is as follows: The corresponding temperature signal obtained from each contact resistance measurement Expressed as: ; in is a useful signal, is the noise signal; Discretely sample the measurement signal to obtain N discrete signals (n), n=0,1,2,...N-1, and perform wavelet transform: ; in is the wavelet coefficient, is the wavelet function, j is the level parameter, and k is the position parameter; The recursive equation of wavelet transform: ; ; in is the scale factor, , Corresponding to the high-frequency and low-frequency parts respectively; The reconstruction formula of wavelet transform: ; According to the reconstruction formula, the first temperature data after noise reduction is obtained and the second temperature data after noise reduction .

[0030] Perform temperature compensation on the noise-reduced temperature data.

[0031] When using an infrared thermal imaging module to measure the contact resistance temperature, the infrared radiation will be attenuated during the transmission in the atmosphere, and the degree of attenuation is affected by the distance between the infrared thermal imaging module and the contact resistance.

[0032] The distance between the infrared thermal imaging module and each contact resistor is recorded as , the error between the temperature measured and the actual temperature during the infrared measurement process Will measure distance As the distance increases, the temperature data measured by the infrared thermal imaging module and the actual temperature data will have an error temperature due to the influence of the measurement distance.

[0033] The infrared thermal imaging position coordinates are ( , , ), contact resistance point set The coordinates are ( , , ), Calculate infrared thermal imaging module and contact resistance distance : ; Error temperature : ; in: For infrared thermal imaging module and contact resistance distance; : Attenuation coefficient ( ).

[0034] Temperature after noise reduction 、 Perform temperature compensation to obtain the compensated temperature , ; ; ; The first temperature data obtained by measurement is the temperature data when each contact resistor of the thermostat is working normally, and is used to perform specific temperature comparison when fluctuation of the thermostat contact resistance is monitored to find the specific faulty contact resistance.

[0035] S3: Based on the real-time current and voltage data, the total resistance of the thermostat is monitored during operation. In combination with the initial database, the abnormal fluctuation of the contact resistance in the thermostat is monitored using the resistance fluctuation threshold monitoring method.

[0036] The main types of contact resistance failures are: poor contact, electric shock oxidation, electric shock contamination, mechanical looseness, and material degradation. The above types of failures will cause the contact resistance to increase abnormally. The increased resistance value is usually several to dozens of times the original resistance value. In extreme cases, it will cause the circuit to be open.

[0037] The total resistance of the thermostat when it is working is obtained based on the current and voltage data monitored in real time.

[0038] As a preferred solution, the resistance fluctuation value Expressed as: ; in is the standard total resistance when the thermostat is working normally, is the total resistance of the thermostat when it is working at time t, is the total contact resistance of the thermostat's internal contact resistance.

[0039] The resistance fluctuation threshold monitoring method is: the resistance fluctuation value monitored in real time and resistance fluctuation threshold For comparison, when the resistance fluctuates Greater than the resistance fluctuation threshold When it is determined that the contact resistance of the thermostat fluctuates abnormally, the fluctuation resistance threshold Determined by the resistance value and quantity of the thermostat contact resistor, different types of thermostats correspond to different fluctuation resistance thresholds .

[0040] Example: The thermostat contains 5 contact resistors with a total resistance of R f , select the contact resistance with the smallest contact resistance as the reference resistance, and record the ratio of the reference resistance to the total resistance as the fluctuation resistance threshold of the thermostat .

[0041] The above resistance fluctuation threshold monitoring method retrieves the standard total resistance in the initial database and total contact resistance Combined with the current sensor and voltage sensor to monitor the total resistance of the thermostat at time t , by calculating the resistance fluctuation value A low-energy real-time monitoring of contact resistance fluctuations is achieved.

[0042] S4: When the resistance fluctuation value of the contact resistance in the thermostat is monitored Greater than the resistance fluctuation threshold When the infrared thermal imaging module is enabled.

[0043] S5: The infrared thermal imaging module scans the contact resistors in the thermostat, collects the second temperature data of each contact resistor in the current thermostat and the third temperature data of the current environment, and performs noise reduction and temperature compensation processing on the second temperature data.

[0044] The second temperature data is the temperature data of each contact resistance when abnormal fluctuations in the contact resistance of the thermostat are detected. Similar noise reduction and temperature compensation processing is required as for the first temperature data to ensure the accuracy of the relative temperature difference method in determining the fault contact resistance.

[0045] The contact resistance fluctuates abnormally. Since the heat absorbed by the resistor is positively correlated with the resistance value, the local temperature may also change suddenly. The collected temperature data of each contact resistor in the current thermostat needs to be processed for noise reduction and temperature compensation.

[0046] S6: Based on the third temperature data, and the first temperature data and the second temperature data after noise reduction and temperature compensation, the relative temperature difference method is used to judge the faulty contact resistance and the fault degree according to the relative temperature difference of each contact resistance, thereby determining the first position information and the first fault degree information of the faulty contact resistance.

[0047] As a preferred solution, the relative temperature difference of the relative temperature difference method is Expressed as: , in, is the first temperature data after noise reduction and temperature compensation; is the second temperature data after noise reduction and temperature compensation, and T is the third temperature data.

[0048] The contact resistance of the fault is determined according to the size of the relative temperature difference. When the relative temperature difference is greater than 35% and less than or equal to 80%, it is monitored as a general fault. When the relative temperature difference is greater than 80%, it is monitored as a serious fault. When the relative temperature difference is greater than 95%, it is monitored as an emergency fault.

[0049] The relative temperature difference method can effectively reduce the calculation error caused by ambient temperature fluctuations and improve the accuracy of monitoring.

[0050] If multiple contact resistors are detected in the temperature mutation area, that is, the positions of some contact resistors are too close, further fault resistance determination is required.

[0051] In different types of thermostats, the distribution positions of various contact resistors are different. In particular, in some thermostats, due to setting reasons, there may be a situation where the contact resistances are concentrated, that is, some contact resistors are too close.

[0052] If the distance is too close and due to many factors such as heat diffusion, if the infrared thermal imaging module used is not accurate enough, the single relative temperature difference method will determine that multiple contact resistors in the area are faulty, and the specific faulty contact resistance determination cannot be achieved.

[0053] However, the use of high-precision thermal imaging cameras will increase the cost burden, resulting in the inability to achieve both low cost and accuracy at the same time.

[0054] In order to take both low cost and accuracy into consideration, step S7 may be further adopted for determination.

[0055] S7: Extract the first position information of all faulty contact resistors output in step S6, cluster the position coordinates based on a preset distance threshold, and generate at least one fault temperature rise area; if the number of contact resistors associated with a certain fault temperature rise area is 1, directly output the position and fault degree of the resistor, that is, the result in step S6; if the number of associations is greater than 1, retrieve the resistance data of each contact resistor in the area, perform resistance threshold fluctuation value determination, and output the second position information and second fault degree information of the final fault resistor.

[0056] The fault temperature rise region is defined as the continuous spatial range where the infrared thermal imaging module scans a significant temperature anomaly. If multiple contact resistors exist within this region, they are linked into the same fault cluster using a coordinate distance clustering algorithm (such as DBSCAN), with the region center coordinates representing the cluster's location.

[0057] The number of contact resistances is determined by detecting the number of resistances associated with the fault temperature rise area output, and one coordinate corresponds to one contact resistance.

[0058] Example 2 See Figure 2 , the step S7 comprises the steps of: S71: Extracting first position information of all faulty contact resistors output in step S6, clustering the position coordinates based on a preset distance threshold, and generating at least one fault temperature rise area; S72: Determine the amount of contact resistance associated with the fault temperature rise area. When the number is equal to 1, the first position information and the first fault degree information of the fault contact resistance in step S6 are output; When the number is greater than 1, the resistance value data of each contact resistor contained in the corresponding position of the fault temperature rise area is retrieved, and the second position information and second fault degree information of the final fault contact resistance are output after fault judgment.

[0059] The method of outputting the second position information and the second fault degree information of the final fault contact resistance after fault judgment comprises the steps of: S73: Calculating resistance threshold fluctuation values ​​of each fault contact resistance; The resistance threshold fluctuation value of each fault contact resistance is calculated as follows: multiple contact resistors are included in the fault temperature rise region, the contact resistance value corresponding to each contact resistor in the fault temperature rise region is obtained, the value range of 3 times the resistance of each contact resistor is recorded as the theoretical fault resistance fluctuation value, and the ratio of the theoretical fault resistance fluctuation value to the total contact resistance is recorded as the resistance threshold fluctuation value of the corresponding resistor; S74: Compare the resistance threshold fluctuation value of each fault contact resistance with the monitored resistance fluctuation value to obtain a fluctuation deviation value, and select the contact resistance corresponding to the minimum fluctuation deviation value. is the fault contact resistance; Example: A thermostat contains 6 contact resistors with resistance values ​​of R1-R6. The total contact resistance is R f， Among them, R2 and R3 are distributed in the same fault temperature rise area. Affected by the accuracy of the infrared thermal imaging module, it is found during the detection that there is a fault contact resistance in the cluster distribution area of ​​R2 and R3. In order to further determine the specific fault resistance, the specific resistance values ​​of R2 and R3 are retrieved at this time, and the values ​​of R2 and R3 are taken as 3 times of the theoretical fault resistance fluctuation values ​​3R2 and 3R3 respectively, thereby obtaining the ratio of the theoretical fault resistance fluctuation value to the total contact resistance, that is, 3R2 / R f and 3R3 / R f .

[0060] Thermostat contact resistance failure types usually include poor contact, contact oxidation, contact burning, mechanical looseness, material deterioration, etc., which will cause the contact resistance value to increase several times the original value.

[0061] The theoretical fault resistance fluctuation value is the preset contact resistance. The resistance value increased after the fault can be equivalent to the resistance fluctuation value. The numerator in the calculation formula is R0-R t Therefore, the resistance threshold fluctuation value is the ratio of the theoretical fault resistance fluctuation value to the total contact resistance, such as 3R2 / R f and 3R3 / R f It can be recorded as 3 2 and 3 3 The actual resistance fluctuation value detected The fluctuation deviation value is obtained by comparing with the resistance threshold fluctuation value of R2 and R3, and the contact resistance corresponding to the minimum fluctuation deviation value is selected as the fault contact resistance.

[0062] S75: Output the second position information and the second fault degree information of the final fault contact resistance.

[0063] When there are multiple contact resistors in the temperature mutation zone, the resistance threshold fluctuation value is calculated by calling the contact resistance value corresponding to the contact resistance, and compared with the monitored resistance fluctuation value. By comparing, the final fault resistance can be determined, which further improves the accuracy of contact resistance fault monitoring and positioning.

[0064] Example 3 See Figure 3 The present invention provides a temperature controller contact resistance fault monitoring and locating system, which is applied to a temperature controller contact resistance fault monitoring and locating method as described above, including a data acquisition module, a data preprocessing module, a contact resistance fluctuation monitoring module and an infrared thermal imaging fault locating module.

[0065] The data acquisition module is composed of a micro-ohmmeter, an infrared thermal imaging module, a current sensor and a voltage sensor, and is used to obtain the number of contact resistors, resistance value data, position data, and temperature data corresponding to each contact resistor in the temperature controller; obtain the position data of the infrared thermal imaging module; obtain the current data and voltage data when the temperature controller is working; and build an initial database of the temperature controller based on the above data.

[0066] The data preprocessing module is used to calculate the distance between the infrared thermal imaging module and each contact resistor based on the position data of each contact resistor and the position data of the infrared thermal imaging module; and is used to perform noise reduction and temperature compensation processing on the temperature data.

[0067] The contact resistance fluctuation monitoring module is used to monitor the total resistance of the thermostat when it is working based on the current and voltage data, and calculate the resistance fluctuation value by comparing the standard total resistance when the thermostat is working, and monitor the abnormal fluctuation of the contact resistance in the thermostat by comparing the size of the resistance fluctuation value.

[0068] The infrared thermal imaging fault location module is used to collect the temperature data of each contact resistor and the ambient temperature, use the relative temperature difference method combined with the resistance threshold fluctuation value to determine the specific contact resistance and fault degree of the fault, and output the location information and fault degree of the fault resistor.

[0069] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as above in terms of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can, without departing from the scope of the technical solution of the present invention, make some changes or modifications to equivalent embodiments using the technical contents disclosed above. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for monitoring and locating a thermostat contact resistance fault, characterized by: The steps include: S1: Obtain the number of contact resistors, resistance value data, position data, and first temperature data corresponding to each contact resistor in the thermostat; obtain the position data of the infrared thermal imaging module; obtain the current data and voltage data of the thermostat in real time when it is working; and construct an initial thermostat database based on the above data; S2: performing noise reduction processing on the first temperature data, and calculating the distance between the infrared thermal imaging module and each contact resistor to perform temperature compensation processing on the first temperature data after the noise reduction processing; S3: Monitor the total resistance of the thermostat during operation based on the current and voltage data acquired in real time. Monitor abnormal fluctuations in contact resistance within the thermostat using a resistance fluctuation threshold monitoring method in combination with the initial database. S4: When it is detected that the resistance fluctuation value of the contact resistance in the temperature controller is greater than the resistance fluctuation threshold, the infrared thermal imaging module is activated; S5: The infrared thermal imaging module scans the contact resistance in the thermostat, collects the second temperature data of each contact resistor in the current thermostat and the third temperature data of the current environment, and performs noise reduction and temperature compensation processing on the second temperature data; S6: Based on the third temperature data and the first temperature data and the second temperature data after noise reduction and temperature compensation, a relative temperature difference method is used to determine the faulty contact resistance and the fault degree according to the relative temperature difference of each contact resistor, thereby determining first position information and first fault degree information of the faulty contact resistor; S7: extracting the first position information of all fault contact resistors output in step S6, clustering the position coordinates based on a preset distance threshold, and generating at least one fault temperature rise area; If the number of contact resistances associated with a certain fault temperature rise region is 1, the result in step S6 is directly output; If the number of associations is greater than 1, the resistance data of each contact resistor in the area is retrieved, the resistance threshold fluctuation value determination is performed, and the second position information and the second fault degree information of the final fault resistor are output.

2. The method for monitoring and locating a thermostat contact resistance fault according to claim 1, characterized in that: The current data and voltage data include: standard current data and standard voltage data when the thermostat is working normally, and working current data and working voltage data of the thermostat when working collected in real time by the current sensor and voltage sensor; the first temperature data is the standard temperature data of each contact resistor when working normally; the second temperature data is the abnormal temperature data of each contact resistor when abnormal fluctuations in the contact resistance are monitored at time t; the third temperature data is the ambient temperature data when abnormal fluctuations in the contact resistance are monitored at time t.

3. The method for monitoring and locating a thermostat contact resistance fault according to claim 1, characterized in that: The initial database is constructed according to the contact resistance distribution characteristics of different types of thermostats, and contact resistance fault monitoring and positioning are performed based on the constructed initial database.

4. The method for monitoring and locating a thermostat contact resistance fault according to claim 1, wherein: The noise reduction process adopts wavelet packet analysis method; The temperature compensation process includes calculating the error temperature caused by the infrared measurement distance and the deviation between the measured temperature and the actual temperature. Expressed as: ， in, For infrared thermal imaging module and contact resistance distance; is the attenuation coefficient.

5. The method for monitoring and locating a temperature controller contact resistance fault according to claim 2, wherein: The resistance fluctuation value Expressed as: ； in, is the standard total resistance when the thermostat is working normally, is the total resistance of the thermostat when it is working at time t, is the total contact resistance inside the thermostat.

6. The method for monitoring and locating a thermostat contact resistance fault according to claim 1, characterized in that: The relative temperature difference Expressed as: ， in, is the first temperature data after noise reduction and temperature compensation; is the second temperature data after noise reduction and temperature compensation, and T is the third temperature data.

7. The method for monitoring and locating a temperature controller contact resistance fault according to claim 1, characterized in that: The step S7 comprises the steps of: S71: Extracting first position information of all faulty contact resistors output in step S6, clustering the position coordinates based on a preset distance threshold, and generating at least one fault temperature rise area; S72: Determine the amount of contact resistance associated with the fault temperature rise area: When the number is equal to 1, the first position information and the first fault degree information of the fault contact resistance in step S6 are output; When the number is greater than 1, the resistance value data of each contact resistor contained in the corresponding position of the fault temperature rise area is retrieved, and the second position information and second fault degree information of the final fault contact resistance are output after fault judgment.

8. The method for monitoring and locating a thermostat contact resistance fault according to claim 7, characterized in that: The method of outputting the second position information and the second fault degree information of the final fault contact resistance after fault judgment comprises the steps of: S73: Calculating resistance threshold fluctuation values ​​of each fault contact resistance; S74: Compare the resistance threshold fluctuation value of each fault contact resistance with the monitored resistance fluctuation value Compare and obtain the fluctuation deviation value, and select the contact resistance corresponding to the minimum fluctuation deviation value is the final fault contact resistance; S75: Output the second position information and the second fault degree information of the final fault contact resistance.

9. The method for monitoring and locating a temperature controller contact resistance fault according to claim 8, characterized in that: The resistance threshold fluctuation value of each fault contact resistance is: multiple contact resistors are included in the fault temperature rise area, the contact resistance value corresponding to each contact resistance in the fault temperature rise area is obtained, 3 times the resistance value of each contact resistance is recorded as the theoretical fault resistance fluctuation value, and the ratio of the theoretical fault resistance fluctuation value to the total contact resistance is recorded as the resistance threshold fluctuation value of the corresponding resistance.

10. A thermostat contact resistance fault monitoring and locating system, implementing a thermostat contact resistance fault monitoring and locating method according to any one of claims 1 to 9, characterized in that: It includes data acquisition module, data preprocessing module, contact resistance fluctuation monitoring module and infrared thermal imaging fault location module; The data acquisition module is composed of a micro-ohmmeter, an infrared thermal imaging module, a current sensor, and a voltage sensor; it is used to obtain the number of contact resistors, resistance value data, position data, and temperature data corresponding to each contact resistor in the thermostat; obtain the position data of the infrared thermal imaging module; obtain the current data and voltage data when the thermostat is working; and construct an initial database of the thermostat based on the above data; The data preprocessing module is used to perform noise reduction and temperature compensation processing on the temperature data; and calculate the distance between the infrared thermal imaging module and each contact resistor based on the position data of each contact resistor and the position data of the infrared thermal imaging module; The contact resistance fluctuation monitoring module is used to monitor the total resistance of the thermostat during operation based on the current and voltage data collected in real time, and to monitor abnormal fluctuations in the contact resistance in the thermostat using a resistance fluctuation threshold monitoring method in combination with the initial database; The infrared thermal imaging fault location module is used to collect temperature data, determine the specific contact resistance and fault degree of the fault by using the relative temperature difference method combined with the resistance threshold fluctuation value, and output the location information of the fault resistance and the fault degree.

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