Wireless passive monitoring system and method for stress and strain of GCB operating mechanism connecting rod

Abstract

The present invention discloses a wireless passive monitoring system and method for stress and strain of a GCB operating mechanism connecting rod, and relates to the field of wireless passive monitoring technology, including a reader sending an energy signal to the energy collection and communication module, and activating a tag circuit microprocessor when the energy received by the energy collection and communication module is greater than a preset energy threshold; the tag circuit microprocessor collects voltage difference data measured by a strain sensor module in real time, and transmits it to the energy collection and communication module; the energy collection and communication module transmits the voltage difference data to the reader, and then to the reader microprocessor, and the reader microprocessor processes the voltage difference data and transmits it to a host computer; the host computer analyzes the voltage difference data, and performs curve drawing and fault judgment. The passive sensor of the present invention does not need to be connected to an external power supply, avoids the wiring connection safety hazards that may exist in traditional active sensors, and improves the isolation performance of the system.

Description

Technical Field

[0001] The invention relates to the technical field of wireless passive monitoring, in particular to a wireless passive monitoring system and method for stress and strain of a GCB operating mechanism connecting rod. Background Art

[0002] In the existing technology of connecting rod stress monitoring, active sensors are often used in gas insulated switchgear (GCB) systems. These sensors are installed on or near the connecting rod structure and are powered and communicated through wires to measure the stress level of the connecting rod in real time. Common types are strain gauge sensors, resistive strain sensors, and piezoelectric sensors. Although they can provide high-precision measurement results, these sensors have some limitations. First, they usually require an external power supply, which increases the complexity of system wiring and maintenance. Secondly, the wiring requirements of the sensor will lead to a complicated installation process and may affect the equipment structure. In addition, the maintenance of the sensor also requires additional time and resources.

[0003] In recent years, with the development of Internet of Things technology, RF wireless communication and energy transmission technology have provided new solutions for the application of passive sensors. Through RF wireless communication technology, sensors can achieve wireless data transmission, while energy transmission technology can achieve wireless power supply for sensors, thus eliminating the dependence on sensor wiring and power supply. This new technology brings many advantages, such as simplifying the system deployment process, reducing maintenance costs, and improving system reliability and availability.

[0004] Based on the above background, the present invention aims to propose a new passive wireless stress sensor solution. The sensor combines RF wireless communication and transmission energy technology, which not only provides a more convenient and efficient solution for the condition monitoring and maintenance of the GCB system, but also opens up new possibilities for the development of future smart power systems. Summary of the invention

[0005] In view of the above-mentioned problems, the present invention is proposed.

[0006] Therefore, the problem to be solved by the present invention is that the prior art usually requires an external power supply, which increases the complexity of system wiring and maintenance. The wiring requirements of sensors in the prior art will lead to a complicated installation process and may affect the device structure.

[0007] To solve the above technical problems, the present invention provides the following technical solutions: a wireless passive monitoring system for stress and strain of a GCB operating mechanism connecting rod, which includes a tag circuit end and a reader end; the tag circuit end includes a strain sensor module, a tag circuit microprocessor and an energy collection and communication module; the reader end includes a reader, a reader microprocessor and a host computer; the reader includes a read-write module and a gain antenna.

[0008] As a preferred solution of the stress-strain wireless passive monitoring system of the GCB operating mechanism connecting rod of the present invention, the strain sensor module is used to measure the stress change of the GCB operating mechanism connecting rod; the tag circuit microprocessor is used to collect the data measured by the strain sensor module and transmit it;

[0009] The energy collection and communication module is used to receive the energy sent by the reader and to transmit information with the reader end; the read-write module is used to send signals to the tag circuit end and receive returned signals; the gain antenna is used to increase the communication distance range between the read-write module and the tag circuit end; the reader microprocessor is used to process the received data and send it to the host computer; the host computer is used to analyze the data, draw curves and make fault judgments.

[0010] In order to solve the above technical problems, the present invention provides the following technical solutions: A method of a wireless passive stress-strain monitoring system for a GCB operating mechanism connecting rod, comprising: the reader sends an energy signal to the energy collection and communication module, and when the energy received by the energy collection and communication module is greater than a preset energy threshold, the tag circuit microprocessor is activated; after the tag circuit microprocessor is activated, the voltage difference data measured by the strain sensor module is collected in real time and transmitted to the energy collection and communication module; the energy collection and communication module transmits the voltage difference data to the reader, and then the reader transmits it to the reader microprocessor, and the reader microprocessor processes the voltage difference data and transmits it to the host computer; the host computer analyzes the voltage difference data, draws curves and makes fault judgments

[0011] As a preferred solution of the method of the stress and strain wireless passive monitoring system of the GCB operating mechanism connecting rod of the present invention, wherein: the strain sensor module is composed of a plurality of strain gauges and fixed resistors, which are connected by a Wheatstone bridge, and a fixed DC voltage is applied to the Wheatstone bridge during operation. ; The resistance of the strain gauge is equal to the fixed resistance; the strain gauge is distributed in different parts of the transmission structure to form a sensor network.

[0012] As a preferred solution of the method of the wireless passive stress-strain monitoring system of the GCB operating mechanism connecting rod of the present invention, after the tag circuit microprocessor is activated, the reader continuously sends an energy signal to keep the energy received by the energy collection and communication module greater than the preset energy threshold. When it is necessary to stop working, the sending of the energy signal is reduced to make the received energy lower than the preset energy threshold, then the tag circuit microprocessor is turned off and the monitoring action is stopped.

[0013] As a preferred solution of the method of the wireless passive stress-strain monitoring system of the GCB operating mechanism connecting rod of the present invention, the data processing includes uploading the collected voltage difference data to the host computer through a low-speed physical quantity acquisition board in accordance with the RS485 communication standard.

[0014] As a preferred solution of the method of the stress-strain wireless passive monitoring system of the GCB operating mechanism connecting rod of the present invention, wherein: the voltage difference data is analyzed including the voltage difference under the normal state of the Wheatstone bridge is 0, when When it is not 0, the relationship between voltage difference, resistance difference and strain is expressed as:

[0015] ,

[0016] in, Expressed as a resistance difference, Represented as a fixed resistor, Expressed as the sensitivity coefficient of the strain gauge, It is expressed as strain. According to the relationship between voltage difference, resistance difference and strain, the strain of the strain gauge is expressed as,

[0017] ,

[0018] Introducing the definition of Young's modulus, we can infer the stress magnitude It is expressed as,

[0019] ,

[0020] Then, based on the definition of stress, the magnitude of the tensile force on the strain gauge can be inferred. It is expressed as,

[0021] ,

[0022] in, Expressed as the Young's modulus of the strain gauge, Expressed as the cross-sectional area of ​​the strain gauge.

[0023] As a preferred solution of the method of the wireless passive stress-strain monitoring system of the GCB operating mechanism connecting rod of the present invention, wherein: the curve drawing includes real-time acquisition of the voltage difference data of each time sequence, and inversely deriving the tension of each time sequence, with the horizontal axis as time and the vertical axis as tension, substituting the tension of each time sequence into the relationship curve between the time sequence and the tension; setting the threshold value as ,Will Substitute into the relationship curve and observe all The points on point; will be The maximum point among the points on the graph is removed, and the remaining points are arranged in time sequence. The time sequence difference between the remaining points is calculated, and the mean of the time sequence difference is obtained and compared with the minimum error time sequence. If it is less than the minimum error time sequence, the observation is carried out normally. If it is greater than the minimum error time sequence, it is judged that the GCB operating mechanism connecting rod measured by the current strain gauge is abnormal; calculate all The mean of the timing differences between the points is compared with the minimum error timing. If it is less than the minimum error timing, the observation is continued normally. If it is greater than the minimum error timing, it is judged that the current strain gauge has fallen off at the measurement point.

[0024] As a preferred solution of the method of the wireless passive stress and strain monitoring system of the GCB operating mechanism connecting rod of the present invention, when it is judged that an abnormality occurs at the GCB operating mechanism connecting rod measured by the current strain gauge, a laser stroke sensor is used to accurately measure the deformation amplitude at the strain gauge measurement point. If the measurement result is a difference between the deformation amplitude and the strain gauge strain calculated, If the measured result is the same as the strain of the strain gauge, it is judged that the GCB operating mechanism connecting rod is damaged; if the measured result is the same as the strain of the strain gauge, If the temperature distribution at the strain gauge is different, an infrared visible light sensor is used to observe the temperature distribution at the strain gauge measurement point, and the current temperature of the strain gauge is obtained based on the temperature distribution. ,Will Substitute the relationship between strain gauge resistance and temperature into middle, for The resistance of the strain gauge at temperature, for The relationship coefficient between the strain gauge resistance and temperature at temperature is and Do the difference Resistance difference at temperature According to the calculation, and For comparison, if , it indicates that the power system is faulty, causing the temperature to rise. , it indicates that the strain gauge is faulty and the strain gauge should be replaced.

[0025] As a preferred solution of the method of the stress-strain wireless passive monitoring system of the GCB operating mechanism connecting rod of the present invention, the strain gauges are distributed at different parts of the transmission structure, including the load point of the GCB operating mechanism connecting rod, the connection point between the GCB operating mechanism connecting rod and the power equipment, and the surface of the GCB operating mechanism connecting rod; the tensile force on the strain gauge at the load point of the GCB operating mechanism connecting rod is expressed as The tensile force on the strain gauge at the connection point between the GCB operating mechanism connecting rod and the power equipment is expressed as The tensile force on the strain gauge on the connecting rod surface of the GCB operating mechanism is expressed as ; When based on The established relationship curve between timing and tension shows that when the GCB operating mechanism connecting rod is damaged, it indicates that the GCB operating mechanism connecting rod is overloaded. A force breaker or overload clutch is added at the load point of the GCB operating mechanism connecting rod to limit the load force transmitted to the connecting rod. The established relationship curve between timing and tension shows that when the GCB operating mechanism connecting rod is damaged, it indicates that there are installation errors and design defects at the connection point between the GCB operating mechanism connecting rod and the power equipment. The structure at the connection point is redesigned to eliminate the error and structural impact. When the established relationship curve between timing and tension determines that the GCB operating mechanism connecting rod is damaged, it indicates that the GCB operating mechanism connecting rod has material defects, and the GCB operating mechanism connecting rod is replaced.

[0026] The beneficial effects of the present invention are: improved isolation: since the passive sensor of the present invention does not need to be connected to an external power supply, it can be isolated from the primary device and the secondary device, avoiding the wiring connection safety hazards that may exist in traditional active sensors, and improving the isolation performance of the system.

[0027] Flexible layout: The feature of the present invention that does not require external power supply makes the passive sensor more flexible in layout. It can be flexibly laid out and deployed according to actual conditions without considering the limitations of power supply lines. It is suitable for monitoring needs in complex environments and special scenarios.

[0028] Reduced maintenance costs: The passive sensor of the present invention does not require an external power supply, which can reduce the maintenance cost of the equipment, avoid the repair and replacement costs that may be caused by power failure, and reduce the operating cost of the system.

[0029] Enhanced reliability: The passive sensor of the present invention does not rely on external power supply, which can reduce monitoring interruption or data loss problems caused by power failure, improve the reliability and stability of the system, and ensure the accuracy and integrity of the monitoring data.

[0030] More accurate fault judgment: The present invention can determine whether it is a GCB operating mechanism connecting rod fault, a power system fault, or a strain gauge fault through steps such as stress analysis and a relationship curve between timing and tension, thereby avoiding misjudgment of the GCB operating mechanism connecting rod mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0032] Figure 1 This is a schematic diagram of a wireless passive strain sensor module for the wireless passive monitoring system for stress and strain of the connecting rod of the GCB operating mechanism in Example 1.

[0033] Figure 2 This is the circuit diagram of the tag end of the stress-strain wireless passive monitoring system for the connecting rod of the GCB operating mechanism in Example 1.

[0034] Figure 3 Schematic diagram of the transmission mechanism strain monitoring system of the wireless passive monitoring system for stress and strain of the connecting rod of the GCB operating mechanism in Example 1.

[0035] Figure 4 Flow chart of the method of the wireless passive monitoring system for stress and strain of the connecting rod of the GCB operating mechanism in Example 2. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0037] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0038] Example 1, reference Figure 1-Figure 3 , which is the first embodiment of the present invention, provides a wireless passive monitoring system for stress and strain of a GCB operating mechanism connecting rod, including a tag circuit end and a reader end, such as Figure 1 shown.

[0039] like Figure 2 As shown, the tag circuit end includes a strain sensor module, a tag circuit microprocessor, and an energy collection and communication module.

[0040] The reader end includes a reader, a reader microprocessor and a host computer, and the reader includes a read-write module and a gain antenna.

[0041] The strain sensor module is used to measure the stress changes of the connecting rod of the GCB operating mechanism.

[0042] The tag circuit microprocessor is used to collect the data measured by the strain sensor module and transmit it.

[0043] The energy collection and communication module is used to receive the energy sent by the reader and to transmit information with the reader.

[0044] The read / write module is used to send signals to the tag circuit end and receive returned signals.

[0045] The gain antenna is used to increase the communication distance range between the read / write module and the tag circuit end.

[0046] The reader microprocessor is used to process the received data and send it to the host computer.

[0047] like Figure 3 As shown, the host computer is used to analyze the data, draw curves and make fault judgments.

[0048] Example 2, reference Figure 4 , which is the third embodiment of the present invention, and which is different from the previous embodiment in that: the method of the wireless passive monitoring system for stress and strain of the connecting rod of the GCB operating mechanism, such as Figure 4 As shown:

[0049] Step 1: The reader sends an energy signal to the energy collection and communication module. When the energy received by the energy collection and communication module is greater than a preset energy threshold, the tag circuit microprocessor is activated.

[0050] Step 2: After the tag circuit microprocessor is activated, the voltage difference data measured by the strain sensor module is collected in real time and transmitted to the energy collection and communication module.

[0051] The strain sensor module consists of several strain gauges and fixed resistors connected by a Wheatstone bridge. When working, a fixed DC voltage is applied to the Wheatstone bridge. .

[0052] The resistance of the strain gauge is equal to the fixed resistance, and the strain gauge is distributed at different parts of the transmission structure to form a sensor network.

[0053] After the tag circuit microprocessor is activated, the reader continues to send energy signals to keep the energy received by the energy collection and communication module greater than the preset energy threshold. When it is necessary to stop working, the sending of energy signals is reduced to make the received energy lower than the preset energy threshold. The tag circuit microprocessor is then turned off and the monitoring action is stopped.

[0054] Step 3: The energy collection and communication module transmits the voltage difference data to the reader, and then the reader transmits it to the reader microprocessor. The reader microprocessor processes the voltage difference data and transmits it to the host computer.

[0055] Data processing is to upload the collected voltage difference data to the host computer through the low-speed physical quantity acquisition board using the RS485 communication standard.

[0056] Step 4: The host computer analyzes the voltage difference data, draws curves and makes fault judgments.

[0057] Voltage difference of Wheatstone bridge in normal state is 0, when When it is not 0, the relationship between voltage difference, resistance difference and strain is expressed as:

[0058] ,

[0059] in, Expressed as a resistance difference, Represented as a fixed resistor, Expressed as the sensitivity coefficient of the strain gauge, Expressed as strain.

[0060] According to the relationship between voltage difference, resistance difference and strain, the strain of the strain gauge can be expressed as:

[0061] ,

[0062] Introducing the definition of Young's modulus, we can infer the stress magnitude It is expressed as,

[0063] ,

[0064] Then, based on the definition of stress, the magnitude of the tensile force on the strain gauge can be inferred. It is expressed as,

[0065] ,

[0066] in, Expressed as the Young's modulus of the strain gauge, Expressed as the cross-sectional area of ​​the strain gauge.

[0067] The voltage difference data of each time sequence is collected in real time, and the tension applied to each time sequence is inversely deduced. The horizontal axis is time, and the vertical axis is tension. The tension applied to each time sequence is substituted into the relationship curve between the time sequence and the tension.

[0068] Set the threshold to ,Will Substitute into the relationship curve and observe all The points on point.

[0069] Will be in The maximum point among the points on the graph is removed, and the remaining points are arranged in time sequence. The time sequence difference between each point in the remaining points is calculated, and the mean of the time sequence difference is obtained and compared with the minimum error time sequence. If it is less than the minimum error time sequence, continuous observation is carried out normally. If it is greater than the minimum error time sequence, it is judged that an abnormality occurs at the connecting rod of the GCB operating mechanism measured by the current strain gauge.

[0070] Calculate all The mean of the timing differences between the points is compared with the minimum error timing. If it is less than the minimum error timing, the observation is continued normally. If it is greater than the minimum error timing, it is judged that the current strain gauge has fallen off at the measurement point.

[0071] Traditional monitoring methods generally determine that an abnormality occurs at the GCB operating mechanism connecting rod, and then determine that the GCB operating mechanism connecting rod is damaged and replace or repair it. However, determining that an abnormality occurs at the GCB operating mechanism connecting rod does not necessarily mean that the GCB operating mechanism connecting rod is really damaged. It may be a misjudgment caused by a circuit system failure or a strain gauge failure. Therefore, in order to reduce misjudgments, the present invention solves this problem by designing logical interactions.

[0072] When it is judged that the GCB operating mechanism connecting rod measured by the current strain gauge is abnormal, the laser travel sensor is used to accurately measure the deformation amplitude of the strain gauge measurement point. If the measurement result is that the deformation amplitude is equal to the strain of the strain gauge calculated, If they are the same, it is determined that the connecting rod of the GCB operating mechanism is damaged. The equality here means approximate equality, and the allowable error is plus or minus one unit.

[0073] If the measurement result is the deformation amplitude and the strain gauge strain If the temperature distribution at the strain gauge is different, an infrared visible light sensor is used to observe the temperature distribution at the strain gauge measurement point, and the current temperature of the strain gauge is obtained based on the temperature distribution. ,Will Substitute the relationship between strain gauge resistance and temperature into middle, for The resistance of the strain gauge at temperature, for The relationship coefficient between the strain gauge resistance and temperature at temperature is and Do the difference Resistance difference at temperature According to the calculation, and For comparison, if , it indicates that the power system is faulty, causing the temperature to rise. , it indicates that the strain gauge is faulty and the strain gauge should be replaced. The approximately equal allowable error here is ±2 degrees Celsius.

[0074] The strain gauges are distributed in different parts of the transmission structure, including the load point of the GCB operating mechanism connecting rod, the connection point between the GCB operating mechanism connecting rod and the power equipment, and the surface of the GCB operating mechanism connecting rod.

[0075] The tensile force on the strain gauge at the load point of the GCB operating mechanism connecting rod is expressed as The tensile force on the strain gauge at the connection point between the GCB operating mechanism connecting rod and the power equipment is expressed as The tensile force on the strain gauge on the connecting rod surface of the GCB operating mechanism is expressed as .

[0076] When based on The established relationship curve between timing and tension shows that when the GCB operating mechanism connecting rod is damaged, it indicates that the GCB operating mechanism connecting rod is overloaded. A force breaker or overload clutch is added at the load point of the GCB operating mechanism connecting rod to limit the load force transmitted to the connecting rod.

[0077] When based on The established relationship curve between timing and tension shows that when the GCB operating mechanism connecting rod is damaged, it indicates that there are installation errors and design defects at the connection point between the GCB operating mechanism connecting rod and the power equipment. The structure at the connection point is redesigned to eliminate the error and structural impact.

[0078] When based on When the established relationship curve between timing and tension determines that the GCB operating mechanism connecting rod is damaged, it indicates that the GCB operating mechanism connecting rod has material defects, and the GCB operating mechanism connecting rod is replaced.

[0079] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. The wireless passive monitoring system for stress and strain of the GCB operating mechanism connecting rod is characterized by: It includes a tag circuit end and a reader end; The tag circuit end includes a strain sensor module, a tag circuit microprocessor, and an energy collection and communication module; The reader end includes a reader, a reader microprocessor and a host computer; The reader includes a read-write module and a gain antenna; The strain sensor module is used to measure the stress change of the connecting rod of the GCB operating mechanism; The tag circuit microprocessor is used to collect data measured by the strain sensor module and transmit it; The energy collection and communication module is used to receive energy sent by the reader and to transmit information with the reader end; When the energy received by the energy collection and communication module is greater than the preset energy threshold, the tag circuit microprocessor is activated. After the tag circuit microprocessor is activated, the reader continues to send energy signals to keep the energy received by the energy collection and communication module greater than the preset energy threshold. When it is necessary to stop working, the sending of energy signals is reduced to make the received energy lower than the preset energy threshold, and then the tag circuit microprocessor is turned off and the monitoring action is stopped; The read / write module is used to send signals to the tag circuit end and receive returned signals; The boost antenna is used to increase the communication distance range between the read / write module and the tag circuit end; The reader microprocessor is used to process the received data and send it to the host computer; The host computer is used to analyze the data, draw curves and perform fault judgment; The curve drawing includes collecting the voltage difference data of each time sequence in real time, and inferring the tension of each time sequence, with the horizontal axis being time and the vertical axis being tension, substituting the tension of each time sequence into the relationship curve between the time sequence and the tension; Set the threshold to F y , y=F y Substitute into the relationship curve and observe all the y Points on and points where F = 0; Will be at y = F y The maximum point among the points on the graph is removed, and the remaining points are arranged in time sequence. The time sequence difference between the remaining points is calculated, and the mean of the time sequence difference is obtained and compared with the minimum error time sequence. If it is less than the minimum error time sequence, continuous observation is performed normally. If it is greater than the minimum error time sequence, it is judged that an abnormality occurs at the connecting rod of the GCB operating mechanism measured by the current strain gauge; Calculate the mean of the timing differences between all points where F=0 and compare it with the minimum error timing. If it is less than the minimum error timing, continue the observation normally. If it is greater than the minimum error timing, it is judged that the current strain gauge has fallen off at the measurement point. When it is determined that an abnormality occurs at the connecting rod of the GCB operating mechanism measured by the current strain gauge, a laser stroke sensor is used to accurately measure the deformation amplitude at the measuring point of the strain gauge. If the measurement result shows that the deformation amplitude is the same as the strain ε of the calculated strain gauge, it is determined that the connecting rod of the GCB operating mechanism is damaged; If the measured result shows that the deformation amplitude is different from the strain ε of the calculated strain gauge, the infrared visible light sensor is used to observe the temperature distribution at the strain gauge measurement point, and the current temperature T of the strain gauge is obtained according to the temperature distribution. Substitute T into the relationship between the resistance and temperature of the strain gauge R T =K T R, R T is the resistance of the strain gauge at temperature T, K T is the coefficient of the strain gauge resistance and temperature at temperature T, and R T Subtract the resistance difference ΔR from R at temperature T T =|R T -R|, according to the calculation, ΔR T Compared with ΔR, if This indicates that the power system is faulty, causing the temperature to rise. If ΔR T ≠ΔR, it indicates that the strain gauge is faulty and the strain gauge should be replaced.

2. A method for using the wireless passive monitoring system for stress and strain of the GCB operating mechanism connecting rod according to any one of claim 1, characterized in that: The reader sends an energy signal to the energy collection and communication module, and when the energy received by the energy collection and communication module is greater than a preset energy threshold, the tag circuit microprocessor is activated; After the tag circuit microprocessor is activated, the voltage difference data measured by the strain sensor module is collected in real time and transmitted to the energy collection and communication module; The energy collection and communication module transmits the voltage difference data to the reader, which is then transmitted to the reader microprocessor. The reader microprocessor processes the voltage difference data and transmits it to the host computer. The host computer analyzes the voltage difference data, draws curves and makes fault judgments; After the tag circuit microprocessor is activated, the reader continuously sends energy signals to keep the energy received by the energy collection and communication module greater than the preset energy threshold. When it is necessary to stop working, the energy signal is reduced to make the received energy lower than the preset energy threshold, and the tag circuit microprocessor is turned off to stop monitoring. The analysis of the voltage difference data includes that the voltage difference ΔU under the normal state of the Wheatstone bridge is 0, and when ΔU is not 0, the relationship between the voltage difference, the resistance difference and the strain is expressed as follows: Among them, ΔR represents the resistance difference, R represents the fixed resistance, K represents the sensitivity coefficient of the strain gauge, and ε represents the strain; According to the relationship between voltage difference, resistance difference and strain, the strain of the strain gauge can be expressed as: Introducing the definition of Young's modulus, the stress magnitude σ is inversely deduced to be: Then, from the definition of stress, the magnitude of the tensile force F on the strain gauge can be deduced as: Where, E represents the Young's modulus of the strain gauge, and S represents the cross-sectional area of ​​the strain gauge; The curve drawing includes collecting the voltage difference data of each time sequence in real time, and inferring the tension of each time sequence, with the horizontal axis being time and the vertical axis being tension, substituting the tension of each time sequence into the relationship curve between the time sequence and the tension; Set the threshold to F y , y=F y Substitute into the relationship curve and observe all the y Points on and points where F = 0; Will be at y = F y The maximum point among the points on the graph is removed, and the remaining points are arranged in time sequence. The time sequence difference between the remaining points is calculated, and the mean of the time sequence difference is obtained and compared with the minimum error time sequence. If it is less than the minimum error time sequence, continuous observation is performed normally. If it is greater than the minimum error time sequence, it is judged that an abnormality occurs at the connecting rod of the GCB operating mechanism measured by the current strain gauge; Calculate the mean of the timing differences between all points where F=0 and compare it with the minimum error timing. If it is less than the minimum error timing, continue the observation normally. If it is greater than the minimum error timing, it is judged that the current strain gauge has fallen off at the measurement point. When it is determined that an abnormality occurs at the connecting rod of the GCB operating mechanism measured by the current strain gauge, a laser stroke sensor is used to accurately measure the deformation amplitude at the measuring point of the strain gauge. If the measurement result shows that the deformation amplitude is the same as the strain ε of the calculated strain gauge, it is determined that the connecting rod of the GCB operating mechanism is damaged; If the measured result shows that the deformation amplitude is different from the strain ε of the calculated strain gauge, the infrared visible light sensor is used to observe the temperature distribution at the strain gauge measurement point, and the current temperature T of the strain gauge is obtained according to the temperature distribution. Substitute T into the relationship between the resistance and temperature of the strain gauge R T =K T R, R T is the resistance of the strain gauge at temperature T, K T is the coefficient of the strain gauge resistance and temperature at temperature T, and R T Subtract the resistance difference ΔR from R at temperature T T =|R T -R|, according to the calculation, ΔR T Compared with ΔR, if This indicates that the power system is faulty, causing the temperature to rise. If ΔR T ≠ΔR, it indicates that the strain gauge is faulty and the strain gauge should be replaced.

3. The method of the wireless passive monitoring system for stress and strain of the GCB operating mechanism connecting rod according to claim 2, characterized in that: The strain sensor module is composed of a plurality of strain gauges and fixed resistors, which are connected by a Wheatstone bridge. When working, a fixed DC voltage U is applied to the Wheatstone bridge. The resistance of the strain gauge is equal to the fixed resistance; The strain gauges are distributed at different locations of the transmission structure to form a sensor network.

4. The method of the wireless passive monitoring system for stress and strain of the GCB operating mechanism connecting rod according to claim 3, characterized in that: The data processing includes uploading the collected voltage difference data to the host computer through the low-speed physical quantity acquisition board in accordance with the RS485 communication standard.

5. The method of the wireless passive monitoring system for stress and strain of the GCB operating mechanism connecting rod according to claim 4, characterized in that: The strain gauges are distributed at different locations of the transmission structure including the load point of the GCB operating mechanism connecting rod, the connection point between the GCB operating mechanism connecting rod and the power equipment, and the surface of the GCB operating mechanism connecting rod; The tensile force on the strain gauge at the load point of the GCB operating mechanism connecting rod is expressed as F z The tensile force on the strain gauge at the connection point between the GCB operating mechanism connecting rod and the power equipment is expressed as F l The tensile force on the strain gauge on the connecting rod surface of the GCB operating mechanism is expressed as F b ; When based on F z The established relationship curve between timing and tension indicates that when the GCB operating mechanism connecting rod is damaged, it indicates that the GCB operating mechanism connecting rod is overloaded. A force breaker or overload clutch is added at the load point of the GCB operating mechanism connecting rod to limit the load force transmitted to the connecting rod. When based on F l The established relationship curve between timing and tension shows that when the GCB operating mechanism connecting rod is damaged, it indicates that there are installation errors and design defects at the connection point between the GCB operating mechanism connecting rod and the power equipment. The structure at the connection point is redesigned to eliminate the error and structural impact. When based on F b When the established relationship curve between timing and tension determines that the GCB operating mechanism connecting rod is damaged, it indicates that the GCB operating mechanism connecting rod has material defects, and the GCB operating mechanism connecting rod is replaced.

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