Thermostat contact resistance fault monitoring and positioning method and system

Abstract

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

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of contact resistance testing, and particularly relates to a temperature controller contact resistance fault monitoring and positioning method and system. BACKGROUND

[0002] A temperature controller is a mechanical device used to automatically adjust or maintain the temperature of equipment or environment. It monitors temperature changes to control the working state of the system, ensuring that the temperature is stable within the set range. The contact resistance of a temperature controller refers to the resistance value between the contact surfaces of the internal switch contacts in the closed state. During the operation of the temperature controller, abnormal changes in contact resistance can affect the performance and lifespan of the equipment, and even pose a safety hazard.

[0003] In the prior art for monitoring the contact resistance fault of a temperature controller, a temperature controller contact resistance test and early warning method is disclosed in Chinese patent CN119178935A. In this patent, a temperature sensor, a current sensor, and a voltage sensor are used to monitor each contact resistance in the temperature controller in real time. This method requires multiple sensors to be arranged inside the temperature controller, which complicates the wiring arrangement. The more contact resistances in the temperature controller, the higher the number and requirements of sensors, and the more data that needs to be processed in real time, resulting in high energy consumption and cost, and poor universality. Therefore, there is an urgent need to design a technology that can monitor the contact resistance of a temperature controller in real time with low energy consumption, fault positioning, and better universality. SUMMARY

[0004] The object of the application can be achieved by the following technical solutions:

[0005] To solve the above-mentioned problems in the prior art, the application provides a temperature controller contact resistance fault monitoring and positioning method and system.

[0006] The first aspect of the present disclosure provides a temperature controller contact resistance fault monitoring and positioning method, comprising the steps of:

[0007] S1: obtaining the contact resistance number, resistance value data, position data, and first temperature data corresponding to each contact resistance in the temperature controller; obtaining the position data of the infrared thermal imaging module; obtaining the current data and voltage data in real time when the temperature controller is working; and constructing an initial database of the temperature controller based on the above data;

[0008] S2: performing noise reduction processing on the first temperature data and calculating the distance between the infrared thermal imaging module and each contact resistance to perform temperature compensation processing on the noise-reduced first temperature data;

[0009] S3: monitoring the total resistance of the temperature controller during operation according to the real-time acquired current data and voltage data, and monitoring the abnormal fluctuation of the contact resistance in the temperature controller by the resistance fluctuation threshold monitoring method in combination with the initial database;

[0010] S4: when 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 enabled;

[0011] S5: the infrared thermal imaging module scans the contact resistance in the temperature controller, collects the second temperature data of each contact resistance in the current temperature controller and the third temperature data of the current environment, and performs noise reduction and temperature compensation processing on the second temperature data;

[0012] S6: based on the third temperature data, and the first temperature data and the second temperature data after noise reduction and temperature compensation processing, the relative temperature difference method is used to determine the fault contact resistance and the fault degree according to the relative temperature difference of each contact resistance, so as to determine the first position information and the first fault degree information of the fault contact resistance;

[0013] S7: extracting the first position information of all fault contact resistances output by 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 area is 1, the result in step S6 is directly output; if the number of associated resistances is greater than 1, the resistance value data of each contact resistance in the area is called, the resistance threshold fluctuation value is determined, and the second position information and the second fault degree information of the final fault resistance are output.

[0014] Specifically, the current data and voltage data include: standard current data and standard voltage data when the temperature controller is normally working, working current data and working voltage data collected by the current sensor and the voltage sensor in real time when the temperature controller is working; the first temperature data is the standard temperature data when each contact resistance is normally working; the second temperature data is the abnormal temperature data of each contact resistance when the contact resistance is monitored to produce abnormal fluctuation at time t; and the third temperature data is the environmental temperature data when the contact resistance is monitored to produce abnormal fluctuation at time t.

[0015] Specifically, the initial database is constructed according to the contact resistance distribution characteristics of different types of temperature controllers, and the contact resistance fault monitoring and positioning is performed according to the constructed initial database.

[0016] Specifically, the noise reduction processing adopts wavelet packet analysis method;

[0017] The temperature compensation processing includes calculating the error temperature caused by the deviation between the measured temperature and the actual temperature caused by the infrared measurement distance, and the error temperature is expressed as:

[0018] ,

[0019] wherein, is the distance between the infrared thermal imaging module and the contact resistance ; is the attenuation coefficient.

[0020] Specifically, the resistance fluctuation value is represented as:

[0021] ,

[0022] wherein, is the standard total resistance when the temperature controller is working normally, is the total resistance of the temperature controller when working for t time, is the total contact resistance inside the temperature controller.

[0023] Specifically, the relative temperature difference is represented as:

[0024] ,

[0025] wherein, is the first temperature data after noise reduction and temperature compensation processing; is the second temperature data after noise reduction and temperature compensation processing, and T is the third temperature data.

[0026] Specifically, the step S7 includes the steps of:

[0027] S71: extracting the first position information of all fault contact resistances output by the step S6, clustering the position coordinates based on a preset distance threshold, and generating at least one fault temperature rise area;

[0028] S72: judging the number of contact resistances associated with the fault temperature rise area,

[0029] when the number is equal to 1, outputting the first position information and the first fault degree information of the fault contact resistance in the step S6;

[0030] when the number is greater than 1, calling the resistance value data of each contact resistance contained in the corresponding position of the fault temperature rise area, and outputting the second position information and the second fault degree information of the final fault contact resistance after fault judgment.

[0031] Specifically, the step of outputting the second position information and the second fault degree information of the final fault contact resistance after fault judgment includes the steps of:

[0032] S73: calculating the resistance threshold fluctuation value of each fault contact resistance;

[0033] S74: comparing the resistance threshold fluctuation value of each fault contact resistance with the monitored resistance fluctuation value to obtain a fluctuation deviation value, and selecting the contact resistance corresponding to the minimum fluctuation deviation value as the final fault contact resistance.

[0034] S75: outputting the second position information and the second fault degree information of the final fault contact resistance.

[0035] Specifically, the resistance threshold fluctuation value of each fault contact resistance is that a plurality of contact resistances are included in the fault temperature rise region, the contact resistance values corresponding to each contact resistance in the fault temperature rise region are obtained, the resistance 3 times value range 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.

[0036] The second aspect of the present disclosure provides a contact resistance fault monitoring and positioning system for a temperature controller, which applies the contact resistance fault monitoring and positioning method.

[0037] The contact resistance fault monitoring and positioning system for a temperature controller specifically comprises a data acquisition module, a data preprocessing module, a contact resistance fluctuation monitoring module, and an infrared thermal imaging fault positioning module.

[0038] 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 contact resistance quantity, resistance value data, position data, and temperature data corresponding to each contact resistance 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 construct an initial database of the temperature controller according to the above data.

[0039] 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 resistance according to the position data of each contact resistance and the position data of the infrared thermal imaging module.

[0040] The contact resistance fluctuation monitoring module is used to monitor the total resistance when the temperature controller is working according to the real-time collected current and voltage data, and monitor the abnormal fluctuation of the contact resistance in the temperature controller by the resistance fluctuation threshold monitoring method in combination with the initial database.

[0041] The infrared thermal imaging fault positioning module is used to collect temperature data, judge the specific contact resistance and fault degree of the fault by the relative temperature difference method in combination with the resistance threshold fluctuation value, and output the position information and fault degree of the fault resistance.

[0042] ​​The contact resistance fluctuation monitoring module is in a working state for monitoring whether the contact resistance abnormally fluctuates in real time; the infrared thermal imaging fault positioning module is in a standby state when no abnormal fluctuation of the contact resistance is monitored, and is in a working state when the abnormal fluctuation of the contact resistance is monitored.

[0043] The present application has the following beneficial effects:

[0044] The present application can realize the same effect of contact resistance fault monitoring by constructing the initial database according to different types of temperature controllers, and has strong versatility.

[0045] The present application can realize long-term low-energy real-time fault monitoring of the contact resistance in the temperature controller by setting the contact resistance fluctuation monitoring module to use the resistance fluctuation threshold monitoring method for non-contact monitoring, without the need for shutdown measurement.

[0046] The present application can realize fault monitoring and positioning of the contact resistance by setting the infrared thermal imaging fault positioning module to use the relative temperature difference method for fault monitoring and positioning of the contact resistance, and to judge the fault degree of the contact resistance according to the temperature difference. BRIEF DESCRIPTION OF DRAWINGS

[0047] In order to facilitate those skilled in the art to understand, the present application will be further described below with reference to the accompanying drawings.

[0048] Figure 1 A step schematic diagram of a temperature controller contact resistance fault monitoring and positioning method provided by the present application embodiment;

[0049] Figure 2 A step schematic diagram of a resistance threshold fluctuation value determination provided by the present application embodiment;

[0050] Figure 3 A structure schematic diagram of a temperature controller contact resistance fault monitoring and positioning system provided by the present application embodiment. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0052] It should be noted that all directionality indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the directionality indications also change accordingly.

[0053] In addition, the description related to "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can be explicitly or implicitly included at least one of the features. In addition, the technical solutions of various embodiments can be combined with each other, but it must be based on the realization of ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, also not within the protection scope required by the present application.

[0054] The present application provides a kind of contact resistance fault monitoring positioning method of thermostat, mainly through three steps to carry out contact resistance fault monitoring positioning:

[0055] First, according to the model of different thermostat, the corresponding initial database is constructed, to ensure universality;

[0056] Second, in combination with initial database, resistance fluctuation threshold monitoring method is used to carry out real-time monitoring to the contact resistance in thermostat, to ensure the low energy consumption of real-time monitoring;

[0057] Finally, when contact resistance fluctuation is monitored, infrared thermal imaging module is enabled to determine the position information and fault degree of contact resistance according to relative temperature difference method and in combination with resistance threshold fluctuation value, to ensure the accuracy of contact resistance fault monitoring.

[0058] Specifically, the present application provides a kind of contact resistance fault monitoring positioning method of thermostat and system, which will be described in detail as follows:

[0059] Embodiment one

[0060] Please refer to Figure 1 The present application provides a kind of contact resistance fault monitoring positioning method of thermostat, including steps:

[0061] S1: the contact resistance quantity, resistance value data, position data and temperature data corresponding to each contact resistance in thermostat are acquired;The position data of infrared thermal imaging module is acquired;The current data and voltage data when thermostat works are acquired;Initial database of thermostat is constructed according to the above data.

[0062] Among them, the number of contact resistance in thermostat and the position data of contact resistance are acquired by the parameters set by thermostat factory, the position data of contact resistance is represented by three-dimensional space coordinates, and the contact resistance point set is constructed according to the number and position data, the i th contact resistance in thermostat is represented as ( , , ), and the position data of the infrared thermal imaging module is also expressed by three-dimensional space coordinates, and the position coordinates of the infrared thermal imaging module are D0 , , The position coordinates of the contact resistance and the position coordinates of the infrared thermal imaging module adopt the same coordinate system.

[0063] Contact resistance in the temperature controller The resistance value data of the contact resistance in the temperature controller is accurately measured by using a micro-ohmmeter, and the total resistance value of the contact resistance in the temperature controller is calculated according to the measured resistance value .

[0064] The temperature data includes: first temperature data : the temperature of each contact resistance in the temperature controller when it works normally; second temperature data : the temperature of each contact resistance when the contact resistance of the temperature controller produces abnormal fluctuations at time t; and third temperature data : the temperature of the environment when the contact resistance of the temperature controller produces abnormal fluctuations at time t.

[0065] The current data and voltage data when the temperature controller works include: standard working current data and voltage data of the temperature controller when it works normally, which are obtained according to the factory parameters of the temperature controller, and are used to calculate the standard total resistance when the temperature controller works normally; and working current data and voltage data of the temperature controller when it works, which are collected by the current sensor and the voltage sensor in real time, and are used to monitor the total resistance of the temperature controller when it works.

[0066] The initial database corresponding to different models of the temperature controller can be constructed according to the S1 step, and the contact resistance fault monitoring with the same effect can be achieved according to the initial database.

[0067] S2: performing noise reduction processing on the first temperature data and calculating the distance between the infrared thermal imaging module and each contact resistance to perform temperature compensation processing on the first temperature data after noise reduction processing.

[0068] Noise reduction processing is performed on the collected temperature data:

[0069] The temperature data that needs to be reduced in noise is the first temperature data and the second temperature data .

[0070] As a preferred solution, the noise reduction processing method is that the collected first temperature data and second temperature data are removed from the noise generated in the sampling process by using wavelet packet analysis.

[0071] The principle of wavelet packet analysis for noise reduction in the temperature data noise reduction processing process is that:

[0072] measured temperature signal composed of a useful signal and a noise signal , the measured temperature signal is subjected to wavelet transform, and the signal is decomposed into high-frequency and low-frequency parts by the wavelet transform;

[0073] is a Gaussian distributed noise signal, and the amplitude will increase with the decrease of the wavelet transform level. The temperature signal is degraded by wavelet transform, so that the amplitude of the noise signal is increased, and then the high-frequency signal is removed to complete the noise reduction;

[0074] The temperature signal with the removed high-frequency signal is subjected to wavelet reconstruction by using a reconstruction function, to obtain the temperature signal after noise reduction .

[0075] As a preferred solution, the wavelet packet analysis method specifically comprises the following steps:

[0076] The corresponding temperature signal measured by each contact resistance is represented as:

[0077] ;

[0078] wherein is a useful signal, is a noise signal;

[0079] The measured signal is subjected to discrete sampling to obtain N discrete signals (n), n=0, 1, 2,...N-1, and wavelet transform is performed:

[0080] ;

[0081] wherein is a wavelet coefficient, is a wavelet function, j is a level parameter, and k is a position parameter;

[0082] The recursive equation of the wavelet transform is:

[0083] ;

[0084] ;

[0085] wherein is a scale coefficient, , corresponding to the high-frequency and low-frequency parts, respectively;

[0086] The reconstruction formula of the wavelet transform is: ​

[0087] ;

[0088] According to the reconstruction formula, the first temperature data after noise reduction is obtained and the second temperature data after noise reduction .

[0089] Perform temperature compensation on the noise-reduced temperature data.

[0090] 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.

[0091] 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.

[0092] The infrared thermal imaging position coordinates are ( , , ), contact resistance point set The coordinates are ( , , ),

[0093] Calculate infrared thermal imaging module and contact resistance distance :

[0094] ;

[0095] Error temperature :

[0096] ;

[0097] in: For infrared thermal imaging module and contact resistance distance; : Attenuation coefficient ( ).

[0098] Temperature after noise reduction 、 Perform temperature compensation to obtain the compensated temperature , ;

[0099] ;

[0100] ;

[0101] The measured first temperature data is the temperature data of the temperature controller when each contact resistance is normally working, and is used for specific temperature comparison when the contact resistance fluctuation of the temperature controller is monitored to find the specific fault contact resistance.

[0102] S3: The total resistance of the temperature controller during working is monitored according to the real-time acquired current data and voltage data, and the contact resistance abnormal fluctuation in the temperature controller is monitored by the resistance fluctuation threshold monitoring method in combination with the initial database.

[0103] The contact resistance fault types mainly include poor contact, contact oxidation, contact pollution, mechanical looseness, and material deterioration. The above fault types will all cause the resistance value of the contact resistance to abnormally increase. The increased resistance value is usually several times to several tens of times of the original resistance value, and in an extreme case, will cause the circuit to be broken.

[0104] The total resistance of the temperature controller during working is obtained according to the real-time monitored current and voltage data.

[0105] As a preferred solution, the resistance fluctuation value is expressed as:

[0106] ;

[0107] wherein R is the standard total resistance of the temperature controller during normal working, Rt is the total resistance of the temperature controller during working at t, Rc is the total contact resistance of the contact resistance inside the temperature controller.

[0108] The resistance fluctuation threshold monitoring method is that the real-time monitored resistance fluctuation value is compared with the resistance fluctuation threshold When the resistance fluctuation value is greater than the resistance fluctuation threshold , it is determined that the contact resistance of the temperature controller has an abnormal fluctuation. The fluctuation resistance threshold is determined by the resistance value and the number of the contact resistance of the temperature controller, and different types of temperature controllers correspond to different fluctuation resistance thresholds .

[0109] Example: the temperature controller contains 5 contact resistances, and the total resistance is R f . The contact resistance with the smallest resistance value is selected as the reference resistance, and the ratio of the reference resistance to the total resistance is recorded as the fluctuation resistance threshold of the temperature controller.

[0110] ​The resistance fluctuation threshold monitoring method, by calling the standard total resistance in the initial database and the total contact resistance and combining the real-time monitoring of the total resistance of the temperature controller at time t obtained by the current sensor and the voltage sensor , realizes a low-energy real-time monitoring of the contact resistance fluctuation by calculating the resistance fluctuation value .

[0111] S4: when 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 enabled.

[0112] S5: the infrared thermal imaging module scans the contact resistance in the temperature controller, collects the second temperature data of each contact resistance in the current temperature controller and the third temperature data of the current environment, and performs noise reduction and temperature compensation processing on the second temperature data.

[0113] The second temperature data is the temperature data of each contact resistance when the contact resistance in the temperature controller is monitored to produce abnormal fluctuation. Similar noise reduction and temperature compensation processing as the first temperature data is required to ensure the accuracy of the relative temperature difference method in determining the faulty contact resistance.

[0114] The contact resistance produces abnormal fluctuation, and since the heat absorbed by the resistance is positively correlated with the resistance value, the local temperature will also produce a sudden change;

[0115] The collected temperature data of each contact resistance in the current temperature controller needs to be processed by noise reduction and temperature compensation.

[0116] S6: based on the third temperature data, and the first temperature data and the second temperature data after noise reduction and temperature compensation processing, the 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 resistance, so as to determine the first position information and the first fault degree information of the faulty contact resistance.

[0117] As a preferred solution, the relative temperature difference of the relative temperature difference method is represented as:

[0118] ,

[0119] wherein, is the first temperature data after noise reduction and temperature compensation processing; is the second temperature data after noise reduction and temperature compensation processing, and T is the third temperature data.

[0120] ​According to the size of the relative temperature difference, the fault contact resistance is determined, 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, and when the relative temperature difference is greater than 95%, it is monitored as an emergency fault.

[0121] The relative temperature difference method can effectively reduce the calculation error caused by environmental temperature fluctuation and improve the accuracy of monitoring.

[0122] If there are multiple contact resistances in the detected temperature mutation area, i.e., the positions of some contact resistances are too close, further fault resistance determination is required.

[0123] In different types of temperature controllers, the distribution positions of each contact resistance are different, especially in some temperature controllers, there may be a situation of contact resistance aggregation distribution due to setting reasons, i.e., some contact resistances are too close.

[0124] If the precision of the adopted infrared thermal imaging module is insufficient, the single relative temperature difference method will determine multiple contact resistances in this area as faults, and cannot realize specific fault contact resistance determination.

[0125] However, the use of high-precision thermal infrared imaging instruments will increase the cost burden, resulting in the inability to simultaneously consider low cost and accuracy.

[0126] In order to simultaneously consider low cost and accuracy, step S7 can be further adopted for determination.

[0127] S7: Extract the first position information of all fault contact resistances output by 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 resistances associated with a certain fault temperature rise area is 1, directly output the position and fault degree of the resistance, i.e., the result in step S6; if the associated number is greater than 1, call the resistance value data of each contact resistance in the area, perform resistance threshold fluctuation value determination, and output the second position information and the second fault degree information of the final fault resistance.

[0128] Among them, the fault temperature rise area is a continuous spatial range with significantly abnormal temperature in the scanning of the infrared thermal imaging module. When there are multiple contact resistances in the area, they are associated as a same fault cluster through a coordinate distance clustering algorithm (such as DBSCAN, etc.), and the area center coordinates represent the cluster position information.

[0129] Among them, the number of contact resistances is determined by detecting the number of resistances associated with the output fault temperature rise area, and one coordinate corresponds to one contact resistance.

[0130] Embodiment two

[0131] Reference Figure 2, the step S7 comprises the steps of:

[0132] S71: extracting the first position information of all fault contact resistances output by the step S6, clustering the position coordinates based on a preset distance threshold, and generating at least one fault temperature rise area;

[0133] S72: judging the number of contact resistances associated with the fault temperature rise area,

[0134] when the number is equal to 1, outputting the first position information and the first fault degree information of the fault contact resistance in the step S6;

[0135] when the number is greater than 1, calling the resistance value data of each contact resistance contained in the corresponding position of the fault temperature rise area, outputting the second position information and the second fault degree information of the final fault contact resistance after fault judgment.

[0136] the step 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:

[0137] S73: calculating the resistance threshold fluctuation value of each fault contact resistance;

[0138] wherein the resistance threshold fluctuation value of each fault contact resistance is: in the fault temperature rise area containing multiple contact resistances, the contact resistance value corresponding to each contact resistance in the fault temperature rise area is obtained, the resistance 3 multiple value range 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;

[0139] S74: comparing the resistance threshold fluctuation value of each fault contact resistance with the monitored resistance fluctuation value to obtain a fluctuation deviation value, and selecting the contact resistance corresponding to the minimum fluctuation deviation value as the fault contact resistance;

[0140] Example: a temperature controller contains 6 contact resistances R1-R6, and the total contact resistance is R f， wherein R2 and R3 are distributed in the same fault temperature rise area, and due to the influence of the infrared thermal imaging module accuracy, it is found that there is a fault contact resistance in the cluster distribution area of R2 and R3 during detection, in order to further determine the specific fault resistance, the specific resistance values of R2 and R3 are called at this time, and the 3 multiple values of R2 and R3 are recorded as the theoretical fault resistance fluctuation values 3R2 and 3R3, so as to obtain the ratio of the theoretical fault resistance fluctuation value to the total contact resistance, i.e. 3R2 / R f and 3R3 / R f .

[0141] The contact resistance fault types of the temperature controller generally include poor contact, contact oxidation, contact burning, mechanical loosening, material deterioration, etc., all of which can make the contact resistance value increase to several times of the original value.

[0142] The theoretical fault resistance fluctuation value is equivalent to the resistance value of the resistance increase after the preset contact resistance fault 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 Corresponding to 3 2 and 3 3

[0143] The actual detected resistance fluctuation value is compared with the resistance threshold fluctuation values of R2 and R3 to obtain a fluctuation deviation value, and the minimum fluctuation deviation value is selected as the fault contact resistance.

[0144] S75: output the second position information and the second fault degree information of the final fault contact resistance.

[0145] When there are multiple contact resistances in the temperature mutation area, the contact resistance values corresponding to the contact resistances are retrieved, the resistance threshold fluctuation values are calculated, and the monitored resistance fluctuation values are compared, so as to determine the final fault resistance, and further improve the positioning accuracy of the contact resistance fault monitoring.

[0146] Embodiment three

[0147] Referring to Figure 3 , the application provides a temperature controller contact resistance fault monitoring and positioning system, which is applied to the temperature controller contact resistance fault monitoring and positioning method as described above, and comprises a data acquisition module, a data preprocessing module, a contact resistance fluctuation monitoring module and an infrared thermal imaging fault positioning module.

[0148] 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 contact resistance quantity, resistance value data, position data and temperature data corresponding to each contact resistance 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 construct an initial database of the temperature controller according to the above data.

[0149] The data preprocessing module is used to calculate the distance between the infrared thermal imaging module and each contact resistance according to the position data of each contact resistance 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.

[0150] The contact resistance fluctuation monitoring module is used for monitoring the total resistance when the temperature controller is working according to the current voltage data, and calculating the resistance fluctuation value by comparing with the standard total resistance when the temperature controller is working, and monitoring the abnormal fluctuation of the contact resistance in the temperature controller by comparing the size of the resistance fluctuation value.

[0151] The infrared thermal imaging fault positioning module is used for collecting the temperature data of each contact resistance and the environmental temperature, judging the specific contact resistance and the fault degree by using the relative temperature difference method and combining the resistance threshold fluctuation value, and simultaneously outputting the position information and the fault degree of the fault resistance.

[0152] The above is only the preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as the above preferred embodiment, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to the above disclosed technical content to obtain equivalent embodiments with equivalent changes, without departing from the technical solution of the present application. Any modification, change and modification of the above embodiments according to the technical essence of the present application, which does not depart from the technical solution of the present application, still belongs to the scope of the technical solution of the present application.

Claims

1. A method of thermostat contact resistance fault monitoring and location, the method comprising: The method comprises the following steps: ​ S1: obtaining the number of contact resistances, resistance value data, position data and first temperature data corresponding to each contact resistance in the temperature controller; obtaining the position data of the infrared thermal imager; obtaining the current data and voltage data of the temperature controller in real time; and constructing an initial database of the temperature controller according to the above data; S2: performing noise reduction processing and temperature compensation processing on the first temperature data, and calculating the distance between the infrared thermal imager and each contact resistance; S3: monitoring the total resistance of the temperature controller during operation according to the real-time current data and voltage data, and monitoring the abnormal fluctuation of the contact resistance in the temperature controller by resistance fluctuation threshold monitoring method in combination with the initial database; The resistance fluctuation threshold monitoring method is: comparing the real-time monitored resistance fluctuation value with the resistance fluctuation threshold , and determining that the contact resistance of the temperature controller has an abnormal fluctuation when the resistance fluctuation value is greater than the resistance fluctuation threshold ; the resistance fluctuation threshold is determined by the resistance value and the number of the contact resistance of the temperature controller, and different types of temperature controllers correspond to different resistance fluctuation thresholds . S4: when 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 enabled; S5: the infrared thermal imaging module scans the contact resistance in the temperature controller, collects the second temperature data of each contact resistance in the current temperature controller and the third temperature data of the current environment, and performs noise reduction and temperature compensation processing on the second temperature data; S6: determining the specific fault resistance and fault degree according to the relative temperature difference of each contact resistance by using the relative temperature difference method, and outputting the first position information and the first fault degree information of the fault contact resistance; The relative temperature difference of the relative temperature difference method is expressed as: wherein, is the first temperature data after noise reduction and temperature compensation processing; is the second temperature data after noise reduction and temperature compensation processing, and T is the third temperature data; S7: detecting the number of contact resistances contained in the output contact resistance position information, when the number is equal to 1, outputting the result in step S6; when the number is greater than 1, determining the final fault resistance by resistance threshold fluctuation range determination, and outputting the second position information and the second fault degree information of the final fault contact resistance.

2. The method of claim 1, wherein: The current data and voltage data include: standard current data and standard voltage data when the temperature controller is normally working, working current data and working voltage data collected by the current sensor and voltage sensor when the temperature controller is working; the first temperature data is standard temperature data when each contact resistance is normally working; the second temperature data is abnormal temperature data of each contact resistance when the contact resistance produces abnormal fluctuation at t; and the third temperature data is environmental temperature data when the contact resistance produces abnormal fluctuation at t.

3. The method of claim 1, wherein: The initial database is constructed according to the contact resistance distribution characteristics of different types of temperature controllers, and the contact resistance fault monitoring and positioning is performed according to the constructed initial database.

4. The temperature controller contact resistance fault monitoring and positioning method according to claim 1, characterized in that: The noise reduction processing adopts wavelet packet analysis method; The temperature compensation process includes calculating an error temperature in which a measured temperature resulting from the infrared distance measurement deviates from an actual temperature, and the error temperature is expressed as: ， wherein is the distance between the infrared thermal imager and the contact resistance is the distance between the infrared thermal imager and the contact resistance is the attenuation coefficient.

5. The method for monitoring and locating a thermostat contact resistance fault according to claim 1, characterized in that: The resistance fluctuation value is represented as: ， wherein, R0 is the standard total resistance of the thermostat when it is working properly, Rt is the total resistance of the thermostat when it is working at time t, Rc is the total contact resistance inside the thermostat.

6. The method of claim 1, wherein: The step S7 comprises the following steps: S71: extracting the contact resistance of the output the number data of the contact resistance contained in the position information of the contact resistance S72: judging the number data, when the number is equal to 1, outputting the fault contact resistance position information and the fault degree in step S6; when the number is greater than 1, calling the resistance value data of each contact resistance contained in the corresponding position, outputting the position information and the fault degree of the fault contact resistance after fault judgment.

7. A method of monitoring and locating contact resistance faults in a thermostat according to claim 6, wherein: The outputting the position information and the fault degree of the fault contact resistance after fault judgment comprises the following steps: S73: calculating the resistance threshold fluctuation range of each resistance; S74: comparing the resistance threshold fluctuation range of each resistance with the monitored resistance fluctuation value S75: selecting the resistance threshold fluctuation range closest to the monitored resistance fluctuation value corresponding resistance faulty resistance; S75: outputting the position information and the fault degree of the fault contact resistance.

8. A method of monitoring and locating contact resistance faults in a thermostat according to claim 7, wherein: The resistance threshold fluctuation range of each resistance is: containing a plurality of contact resistances in the call position, obtaining the resistance value corresponding to each contact resistance in the call position, recording the 1-5 times value range of the resistance of each contact resistance as the pre-fault resistance fluctuation range, and recording the ratio of the pre-fault resistance fluctuation range to the total contact resistance as the resistance threshold fluctuation range of the corresponding resistance.

9. A thermostat contact resistance fault monitoring and locating system applied to a thermostat contact resistance fault monitoring and locating method according to any one of claims 1-8, characterized in that: It comprises 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 imager, a current sensor and a voltage sensor; is used for obtaining the number of contact resistances, resistance value data, position data and temperature data corresponding to each contact resistance in the temperature controller; obtaining the position data of the infrared thermal imager; obtaining the current data and voltage data when the temperature controller is working; and constructing an initial database of the temperature controller according to the above data; The data preprocessing module is used for noise reduction and temperature compensation processing of the temperature data; and calculating the distance between the infrared thermal imager and each contact resistance according to the position data of each contact resistance and the position data of the infrared thermal imager; The contact resistance fluctuation monitoring module is used for monitoring the total resistance when the temperature controller is working according to the real-time collected current and voltage data, and monitoring the abnormal fluctuation of the contact resistance in the temperature controller by the resistance fluctuation threshold monitoring method combined with the initial database; The infrared thermal imaging fault positioning module is used for collecting temperature data, judging the specific contact resistance and fault degree of the fault by the relative temperature difference method combined with the resistance threshold fluctuation range, and simultaneously outputting the position information and fault degree of the fault resistance.

Images