A metering box anti-damage electrical monitoring loop system and method based on mechanical displacement analog quantity capture

Abstract

The application discloses a kind of metering box anti-damage electrical monitoring loop system and method based on mechanical displacement analog quantity capture, it is related to electrical equipment safety and state monitoring technical field.The system, mixed signal generation node generates low-frequency reference pulse superimposed with high-frequency detection carrier, and inject displacement sensing feedback network.Displacement sensing feedback network changes the response amplitude of low-frequency reference pulse based on the macroscopic opening and closing amplitude of metering box door body, while the high-frequency detection carrier is attenuated based on the microscopic contact impedance change when the box door is forced.The system separates the low-frequency response amplitude and carrier attenuation ratio, and generates a status marker when the carrier attenuation ratio exceeds the high-frequency carrier attenuation threshold.If the low-frequency response amplitude breaks through the displacement alarm threshold within the state tracking time limit after detecting the status marker, it is determined that a real physical damage has occurred and an open control signal is output.The present scheme realizes accurate identification and physical blocking of physical damage behavior under complex working conditions.

Description

Technical Field

[0001] This invention relates to the field of electrical equipment safety and condition monitoring technology, and in particular to a metering box anti-vandalism electrical monitoring circuit system and method based on mechanical displacement analog quantity capture. Background Technology

[0002] Metering boxes in power systems are core devices for electricity metering, and their operational status directly affects the normal operation of the power grid and the regular electricity consumption of users. During actual deployment and long-term operation, metering boxes typically face alternating changes in the external natural environment and potential human-induced contact. To ensure the safety of internal wiring and electrical components, the industry commonly equips metering boxes with status monitoring devices to detect changes in mechanical displacement, such as the opening and closing of the box door. Early monitoring methods relied heavily on conventional physical limit switches or single digital sensors to determine the box's open state; these basic solutions provided a certain level of equipment status reference information.

[0003] In complex real-world applications, the metering box may be subjected to extremely slow pushing forces or minor localized prying. Drastic fluctuations in temperature and humidity in the natural environment can cause thermal expansion and contraction of the box material, and the passage of heavy vehicles in the vicinity can also bring continuous mechanical vibration interference to the box. These objective environmental factors often cause minor deformations or transient displacement fluctuations in the box structure, leading to false triggering or missed detections by conventional sensors.

[0004] When faced with the complex changes in simulated mechanical displacement, accurately capturing the changes in the microscopic state of the door under pressure and preparing for tracking before macroscopic displacement occurs has been a continuous optimization direction in the field of electrical monitoring. To further enhance the monitoring circuit's ability to identify abnormal physical state interventions, the industry has gradually begun to explore technical routes that combine multi-frequency signal processing technology with displacement sensing structures, aiming to achieve a more reliable judgment between environmental interference and actual destructive behavior. Summary of the Invention

[0005] The purpose of this invention is to provide a metering box anti-vandalism electrical monitoring circuit system and method based on mechanical displacement analog quantity capture. Through the collaborative processing and logical tracking of dual-frequency analog signals, it overcomes environmental fluctuation interference and achieves accurate identification and electrical interruption of real physical vandalism.

[0006] In a first aspect, the present invention provides a metering box anti-vandalism electrical monitoring circuit system based on mechanical displacement analog quantity capture, including a hybrid signal generation node, a displacement sensing feedback network and an execution blocking terminal; The hybrid signal generation node generates a low-frequency reference pulse superimposed with a high-frequency probe carrier and continuously injects it into the displacement sensing feedback network. The displacement sensing feedback network changes the response amplitude of the low-frequency reference pulse based on the macroscopic opening and closing amplitude of the metering box door, and attenuates the high-frequency detection carrier based on the microscopic contact impedance change of the metering box door when it is forced. The hybrid signal generating node receives the feedback signal, separates the low-frequency response amplitude and carrier attenuation ratio, and performs anti-sabotage blocking steps: The carrier attenuation ratio is continuously compared with a preset high-frequency carrier attenuation threshold. When the carrier attenuation ratio exceeds the high-frequency carrier attenuation threshold, it is determined that the potential damage monitoring stage has been entered and a status mark has been generated. If the low-frequency response amplitude exceeds the displacement alarm threshold within the state tracking time limit after the state flag is detected, it is determined that a real physical damage has occurred, and a disconnection control signal is output to the execution blocking terminal. If the low-frequency response amplitude slowly exceeds the displacement alarm threshold, but the status marker is not detected during the potential damage monitoring stage, it is determined to be a natural environmental thermal expansion and contraction offset, and the disconnection control signal is blocked.

[0007] Optionally, the displacement sensing feedback network is connected in series with a carbon film resistor element and a metal hairspring contact; The metal hairspring contacts abut against the surface of the carbon film resistor element; When the metering box door is forced to move, the compression state between the metal hairspring and the carbon film resistor element undergoes a microscopic change, causing a jump in the capacitance parameter of the contact surface. The abrupt change in the capacitance parameter of the contact surface constitutes the physical cause of the attenuation of the high-frequency probe carrier.

[0008] Optionally, the mixed signal generation node is internally equipped with a hardware envelope detection port and a direct sampling port; The feedback signal is simultaneously sent to the hardware envelope detector port and the direct sampling port; The direct sampling port reads the long-period level and converts it into the low-frequency response amplitude; The hardware envelope detection port extracts the high-frequency envelope and quantifies the voltage drop amplitude of the high-frequency envelope as the carrier attenuation ratio, achieving pure hardware frequency band isolation without relying on pure software digital filtering.

[0009] Optionally, the execution blocking terminal contains a trip holding coil and a hardware self-locking closed loop; After the mixed signal generating node outputs the disconnection control signal, the hardware self-locking closed loop uses a thyristor to complete continuous conduction, forcing the trip holding coil to remain in the energized state. Even if saboteurs perform a complete power cut and force a short circuit to reconnect the power, the thyristor will be triggered to conduct again by the extremely high surge change at the moment the abnormal power supply recovers, maintaining the physical blocking state and preventing power-off restart evasion behavior. A maintenance switch is connected in series on the anode main circuit of the thyristor. During normal power supply or power outage maintenance and restoration, it allows manual operation to cut off the holding current flowing through the thyristor, forcing the thyristor to exit the conduction self-locking state, thereby realizing legal unlocking and equipment reset.

[0010] Optionally, the mixed signal generation node compares the low-frequency response amplitude with the open-circuit reference threshold in real time; In normal standby mode, the amplitude of the low-frequency response is always higher than the lowest potential determined by the current-limiting bias resistor; If the low-frequency response amplitude drops instantaneously to the reference zero potential without any change in the carrier attenuation ratio, it is determined that the displacement sensing feedback network has been damaged by wire cutting and circuit breaking, and the disconnection control signal is directly triggered.

[0011] Optionally, for the extremely slow failure condition of the micro hydraulic strut, the carrier attenuation ratio may be lower than the high-frequency carrier attenuation threshold. The mixed signal generation node extracts multiple low-frequency response amplitudes at equal intervals according to a preset period, and calculates the deviation slope between adjacent periods; If multiple consecutive deviations are positive and the range is below the set fluctuation limit, it is determined that the device is subjected to a constant thrust and opens very slowly, unaffected by the status flag, and the disconnection control signal is forcibly triggered.

[0012] Optionally, drastic changes in external temperature and humidity can cause the distributed capacitance parameter of the contact surface to drift naturally. The hybrid signal generation node incorporates environmental temperature and humidity parameters to construct a dynamic compensation lookup table matrix. The hybrid signal generation node retrieves the dynamic compensation lookup table matrix in real time based on the currently acquired environmental temperature and humidity parameters, and dynamically adjusts or lowers the trigger threshold of the high-frequency carrier attenuation threshold to prevent feature misjudgment caused by severe weather.

[0013] Optionally, when the metering box is subjected to vibration interference from a heavy truck, the carrier attenuation ratio exhibits high-frequency sinusoidal oscillation, but the low-frequency response amplitude fluctuates symmetrically around the original macroscopic position. The mixed signal generating node extracts the symmetrical extreme values ​​of the low-frequency response amplitude. If none of the symmetrical extreme values ​​exceed the displacement alarm threshold and the oscillation mean does not shift, it is determined to be environmental vibration interference, and the recorded status markers are actively cleared.

[0014] Optionally, before the physical circuit is disconnected due to damage, the mixed signal generation node stores the carrier attenuation ratio and the low-frequency response amplitude captured at the moment before the power failure into a non-volatile ferroelectric storage module. An energy storage electrolytic capacitor is connected in parallel at the power input terminal of the mixed signal generation node, with a capacitance set to 470μF to 1000μF. The non-volatile ferroelectric storage module possesses microsecond-level high-speed write characteristics. When the external power supply is completely interrupted, the energy storage electrolytic capacitor provides a millisecond-level support power supply window through its own discharge. The non-volatile ferroelectric storage module utilizes this millisecond-level support power supply window to solidify the data, providing reliable underlying waveform data for subsequent tracing of the physical process of destruction. Secondly, this invention provides a method for a metering box anti-vandalism electrical monitoring circuit based on mechanical displacement analog quantity capture, using the metering box anti-vandalism electrical monitoring circuit system based on mechanical displacement analog quantity capture as described in any one of the first aspects, comprising the following steps: A low-frequency reference pulse superimposed with a high-frequency probe carrier is generated using a hybrid signal generation node and continuously injected into the displacement sensing feedback network. The displacement sensing feedback network is used to change the response amplitude of the low-frequency reference pulse based on the macroscopic opening and closing amplitude of the metering box door, while the high-frequency detection carrier is attenuated based on the microscopic contact impedance change of the metering box door when it is forced. The hybrid signal generating node receives the feedback signal, separates the low-frequency response amplitude and carrier attenuation ratio, and performs anti-sabotage blocking steps: The carrier attenuation ratio is continuously compared with a preset high-frequency carrier attenuation threshold. When the carrier attenuation ratio exceeds the high-frequency carrier attenuation threshold, it is determined that the potential damage monitoring stage has been entered and a status mark has been generated. If the low-frequency response amplitude exceeds the displacement alarm threshold within the state tracking time limit after the state flag is detected, it is determined that a real physical damage has occurred, and a disconnection control signal is output to the execution blocking terminal. If the low-frequency response amplitude slowly exceeds the displacement alarm threshold, but the status marker is not detected during the potential damage monitoring stage, it is determined to be a natural environmental thermal expansion and contraction offset, and the disconnection control signal is blocked.

[0015] The present invention has achieved the following beneficial effects: This invention continuously injects a low-frequency reference pulse superimposed with a high-frequency probe carrier into the displacement sensing feedback network through a hybrid signal generation node, enabling simultaneous capture of both the macroscopic opening and closing amplitude and the microscopic contact impedance changes of the metering box door. The system separates the low-frequency response amplitude and the carrier attenuation ratio and executes corresponding anti-vandalism blocking steps. When the carrier attenuation ratio exceeds a preset limit, a status marker is generated in advance. Subsequently, based on the change in the low-frequency response amplitude, it determines whether to output a disconnection control signal to the blocking terminal. This dual-frequency signal joint monitoring and pre-tracking method can shield disconnection commands or actively clear status markers under conditions such as thermal expansion and contraction in the natural environment or vibration interference from heavy trucks. Simultaneously, it can forcibly trigger the disconnection control signal when encountering physical wire cutting or constant thrust causing extremely slow opening damage. In conjunction with the thyristor and tripping holding coil inside the blocking terminal, the system can maintain a stable blocking state after outputting the disconnection control signal, improving the accuracy of status monitoring and anti-vandalism capabilities of the metering box in complex field environments.

[0016] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0017] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a block diagram of the electrical monitoring circuit system module for preventing damage to the metering box in an embodiment of the present invention; Figure 2 This is a diagram showing the internal structure of the mixed signal generation node in an embodiment of the present invention; Figure 3 This is a schematic diagram of the signal separation principle in an embodiment of the present invention; Figure 4 This is a diagram illustrating the hardware triggering and self-locking closed-loop structure of the blocking terminal in this embodiment of the invention. Figure 5 This is the main flowchart of the electrical monitoring circuit method for preventing damage to the metering box in an embodiment of the present invention. Detailed Implementation

[0019] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0020] This embodiment provides a tamper-proof electrical monitoring circuit system for metering boxes based on the capture of analog mechanical displacement quantities. Its system module structure diagram is as follows: Figure 1 As shown, it includes a mixed signal generation node, a displacement sensing feedback network, and an execution blocking terminal.

[0021] In this embodiment, combined with Figure 2 and Figure 3 As shown, the mixed signal generation node generates a low-frequency reference pulse superimposed with a high-frequency probe carrier and continuously injects it into the displacement sensing feedback network. It can be understood that the mixed signal generation node is equipped with an independent reference clock source and waveform generation circuit. It generates a low-frequency reference pulse with a fixed period through a digital-to-analog conversion unit, and simultaneously generates a high-frequency probe carrier through a high-frequency oscillation circuit. The high-frequency probe carrier is superimposed on the low-frequency reference pulse via an impedance matching network to form a mixed signal, which is continuously injected into the displacement sensing feedback network deployed at the metering box door structure through a feeder. Specifically, the center frequency of the low-frequency reference pulse is set between 10Hz and 50Hz, and the center frequency of the high-frequency probe carrier is set between 400kHz and 800kHz. The impedance matching network uses a conventional LC-type filter matching circuit configured in the output branch of the low-frequency generation circuit to assist in the physical isolation of signals in different frequency bands and utilizes its high-frequency choke characteristics to prevent the high-frequency probe carrier at the signal mixing node from backflowing into the low-frequency generation circuit. In practical engineering implementation, the series inductor of the LC-type filter matching circuit is connected between the low-frequency generation circuit and the signal mixing node. A conventional color-coded inductor is used, with an empirical inductance value ranging from 4.7mH to 10mH. The parallel filter capacitor is placed near the low-frequency generation circuit to bypass the high-frequency noise generated by the low-frequency source itself. A CBB polypropylene film capacitor is selected, with a capacitance value set from 0.1μF to 0.47μF. This basic component combination utilizes physical inductive reactance distribution, eliminating the need for complex filtering algorithms. The series inductor alone can form a high-impedance shield greater than 1kΩ in the 400kHz to 800kHz frequency band. While preventing the high-frequency probe carrier from back-entering the low-frequency branch, the series inductor effectively isolates the high-frequency probe carrier, thus preventing the high-frequency signal from being directly bypassed to ground by the parallel filter capacitor, effectively achieving frequency band isolation. Furthermore, the displacement sensing feedback network changes the response amplitude of the low-frequency reference pulse based on the macroscopic opening and closing amplitude of the metering box door, and simultaneously attenuates the high-frequency detection carrier based on the microscopic contact impedance change of the metering box door when under stress. Specifically, when the metering box door undergoes macroscopic displacement, its mechanical motion traction changes the resistive voltage divider structure inside the displacement sensing feedback network. This resistive change acts on the low-frequency reference pulse, causing a voltage drop change in the low-frequency signal amplitude fed back to the mixed signal generation node. When the metering box door is under stress but has not yet undergone macroscopic displacement, elastic deformation occurs between the door structural components. This mechanical stress is transmitted to the displacement sensing feedback network, causing changes in the contact surface parameters, and altering the distributed capacitance and parasitic inductance parameters formed between the contact surfaces. The change in capacitive reactance causes attenuation of the high-frequency detection carrier on the transmission path, resulting in a change in the amplitude of the high-frequency detection carrier.

[0022] In this embodiment, the mixed signal generation node receives the feedback signal, separates the low-frequency response amplitude and carrier attenuation ratio, and performs anti-tampering blocking steps. Specifically, the feedback signal returns to the mixed signal generation node via a feeder, and the signal separation unit uses a low-pass filter to extract the response profile of the low-frequency reference pulse and obtain the low-frequency response amplitude. Considering the computing power limitations of the field microprocessor, the low-pass filter adopts a second-order active low-pass filter circuit, with its cutoff frequency fixed at 100Hz. By selecting a general-purpose operational amplifier to construct a standard Sallen-Key second-order filter topology, the two frequency band determining resistors in its internal double-section RC network are both 1.5kΩ, and the two filter capacitors are both 1μF, directly filtering out high-frequency components above 400kHz with pure hardware combination, eliminating the need for digital filtering steps that consume system memory. At the same time, the feedback signal is filtered by a high-frequency bandpass filter to extract the frequency band where the high-frequency detection carrier is located, and fed into the detector circuit to calculate the amplitude drop ratio of the high-frequency carrier relative to the transmission state, i.e., the carrier attenuation ratio. Specifically, the high-frequency bandpass filter adopts a second-order passive LC bandpass network topology, with a series inductance of 10μH and a parallel capacitance of 10nF in its signal transmission path, so that the center resonant frequency falls within the 400kHz to 800kHz frequency band, and accurately filters out low-frequency reference pulses and their higher harmonics in a purely hardware manner.

[0023] In the anti-sabotage blocking step, the carrier attenuation ratio is continuously compared with a preset high-frequency carrier attenuation threshold. When the carrier attenuation ratio exceeds the high-frequency carrier attenuation threshold, it is determined that the system has entered the potential sabotage monitoring stage and a status flag is generated. It is understood that the high-frequency carrier attenuation threshold is a parameter threshold set by the system. When the calculated carrier attenuation ratio is greater than this high-frequency carrier attenuation threshold, the mixed signal generation node determines that the metering box is in the initial stage of being subjected to external force, sets the corresponding timing status flag in the register, and locks it.

[0024] Furthermore, if the low-frequency response amplitude exceeds the displacement alarm threshold within the state tracking time limit after the detection of the state marker, it is determined that a real physical damage has occurred, and a disconnection control signal is output to the execution blocking terminal. System parameters are statically calibrated during the power-on phase at the factory or during the initial field deployment. The microcontroller continuously collects the background feedback signal for a specified duration in a disturbance-free standby state, extracts the maximum fluctuation peak of the carrier attenuation ratio during this period, and adds 15% to 20% engineering redundancy margin as a fixed parameter for the high-frequency carrier attenuation threshold. The displacement alarm threshold is directly related to the maximum mechanical clearance of the corresponding model metering box door latch. The extreme value of the low-frequency response potential change at the boundary of this physical clearance is measured by a vernier caliper and written into the register as the alarm threshold. The setting of the state tracking time limit is limited by the elastic damping release characteristics of the metal hairspring used. The timing span of the tendril rebounding to the resting state after being forced is captured by an oscilloscope, and this span value is directly assigned to the microcontroller's internal timer as the window duration limit. Specifically, after generating a status flag, the hybrid signal generating node initiates a preset status tracking time limit and continuously acquires the low-frequency response amplitude. If the detected change in the low-frequency response amplitude exceeds the displacement alarm threshold representing the normal gap of the door, the hybrid signal generating node determines that the system has been damaged and outputs a disconnect control signal to the execution blocking terminal.

[0025] If the low-frequency response amplitude slowly exceeds the displacement alarm threshold, but the status marker is not detected during the potential damage monitoring phase, it is determined to be a natural environmental thermal expansion and contraction offset, and the disconnection control signal is blocked. It is understood that when changes in ambient temperature cause thermal expansion and contraction of the metering box, the box deformation also affects the displacement sensing feedback network, causing the low-frequency response amplitude to drift and exceed the displacement alarm threshold. Since thermal stress release does not cause a sudden change in the distributed capacitance of the contact surface, the carrier attenuation ratio remains within the high-frequency carrier attenuation threshold, and the system does not detect the status marker during the potential damage monitoring phase. At this time, the mixed signal generation node determines that the macroscopic displacement is a natural environmental offset and blocks the disconnection control signal. During this determination process, the system presets the environmental drift time threshold to be 30 to 60 minutes. Only when the time taken for the change in the low-frequency response amplitude to accumulate from the static baseline to reach the displacement alarm threshold is greater than this environmental drift time threshold is the system determined to be a slow exceedance. The specific timing trigger conditions are as follows: the microcontroller monitors the low-frequency response amplitude in real time. When the difference between the amplitude and the static baseline is greater than 0.1V (the hardware noise shielding threshold set by the system) for the first time, the internal hardware timer is activated to start timing. During this period, if the amplitude falls back to within 0.1V, the timer is cleared and reset. If it continues to deviate in one direction until it touches the displacement alarm threshold, the system immediately reads the current cumulative value of the timer and compares it with the environmental drift time threshold.

[0026] In this embodiment, the displacement sensing feedback network is connected in series with a carbon film resistor element and a metal hairspring contact, with the metal hairspring contact abutting against the surface of the carbon film resistor element. Specifically, the carbon film resistor element is mounted on the stationary part of the metering box door, and the metal hairspring contact is assembled on the moving part of the door. When the door is closed, the metal hairspring contact abuts against the surface of the carbon film resistor element to form an electrical contact circuit. To cope with low-frequency vibrations such as those from heavy trucks, the metal hairspring contact adopts a V-shaped bent spring structure with pre-tension, and the bending angle is set to 120 degrees to 150 degrees. When assembled and closed, its root is compressed, generating a constant physical contact elastic force of 0.5N to 1.5N. This pre-tension elastic force ensures that the contact only undergoes elastic changes in the microscopic contact area under external non-destructive vibration interference, avoiding macroscopic bounce and circuit breakage. When the gate macroscopically opens and closes, the metal hairspring contacts slide relative to each other on the surface of the carbon film resistor element, changing the length of the carbon film connected to the circuit, thereby changing the DC impedance of the network and modulating the response amplitude of the low-frequency reference pulse.

[0027] Furthermore, when the metering box door is forcibly pried open, the compression state between the metal hairspring contact and the carbon film resistor element undergoes a microscopic change, causing a jump in the distributed capacitance parameter of the contact surface; this jump in the distributed capacitance parameter constitutes the physical cause of the high-frequency detection carrier attenuation. It can be understood that when the metering box door is locally pried open by external force, the structure near the force point deforms, and the stress is transmitted to the contact area between the metal hairspring contact and the carbon film resistor element, causing a change in the contact pressure of the metal hairspring contact or lateral misalignment. The contact area between the metal hairspring contact and the carbon film surface, as well as the gap in the surrounding air medium, fluctuate accordingly, causing a jump in the distributed capacitance parameter of the contact surface. The change in capacitive reactance alters the impedance matching state of the high-frequency path, leading to a decrease in the amplitude of the high-frequency detection carrier, resulting in high-frequency detection carrier attenuation. Under normal conditions, when the metal hairspring contact is statically in contact with the carbon film surface, its background distributed capacitance is in the small range of 15pF to 45pF. The high-frequency probe carrier wave of 400kHz to 800kHz is extremely sensitive to the minute deformation of the pF-level base capacitor. Based on this physical characteristic, the system can determine the state by directly acquiring the millivolt-level voltage drop after detection, avoiding real-time mathematical conversion of parasitic capacitance. In this embodiment, the total resistance range of the carbon film resistor element is set to 10kΩ to 20kΩ, and its internal current-limiting bias resistor is set to 1kΩ to 5kΩ. To avoid complex real-time calculation of capacitive reactance, the system adopts an empirical calibration method to establish the correspondence between capacitive reactance change and carrier attenuation: before leaving the factory, a stepped mechanical stress is applied to the door body using a push-pull force gauge, and the high-frequency probe carrier voltage drop amplitude under the corresponding stress is measured. Based on this, a one-dimensional discrete lookup table matrix of forced stress-carrier attenuation ratio is generated and stored in memory. Specifically, the stepped mechanical stress is applied step by step with a fixed engineering empirical step value of 5N to 10N. The one-dimensional discrete lookup table matrix is ​​directly entered into groups based on the physical measurement data of the basic gauge, without the need for arithmetic fitting. In actual operation, the system directly compares the currently sampled carrier attenuation ratio with the lookup table matrix to quantify the changes in the microscopic physical state. The quantified current forced stress physical value does not interfere with the real-time anti-vandalism blocking logic's judgment, but serves as auxiliary traceability data. When the status flag is generated or the system experiences a power outage, it is stored in the non-volatile ferroelectric storage module via the data bus, available only for on-site maintenance personnel to retrieve afterward for intuitive assessment of the mechanical force scale of external damage to the metering box door.

[0028] In this embodiment, the mixed signal generation node is internally equipped with a hardware envelope detection port and a direct sampling port; the feedback signal is synchronously fed into the hardware envelope detection port and the direct sampling port. It can be understood that the feedback signal is physically split at the input stage of the mixed signal generation node by a demultiplexer, and sent to the hardware envelope detection port and the direct sampling port respectively, with physical channel isolation to avoid sampling aliasing during signal processing. Specifically, the demultiplexer employs an independent voltage follower circuit based on a dual-channel broadband operational amplifier; the feedback signal is synchronously connected to the non-inverting inputs of the two voltage followers. Leveraging the operational amplifier's extremely high input impedance and extremely low output impedance characteristics, a unidirectional signal buffer and hard impedance isolation are formed between the direct sampling port and the hardware envelope detection port.

[0029] Specifically, the direct sampling port reads long-period level signals and converts them into the low-frequency response amplitude. The direct sampling port is equipped with a buffer amplifier and a hardware integrator. The hardware integrator filters out high-frequency remnants and power frequency interference, extracting a long-period DC level signal representing macroscopic displacement. Specifically, the hardware integrator uses a conventional passive RC integrator network with a series resistor set to 100kΩ and a parallel capacitor set to 1μF to 4.7μF. By constructing a fixed hardware time constant greater than 100 milliseconds, it directly and smoothly filters out power frequency fluctuations of 50Hz and its harmonics. After quantization by an analog-to-digital converter, the signal is converted into a specific low-frequency response amplitude value.

[0030] Specifically, the analog-to-digital converter (ADC) uses a standard 12-bit ADC with a reference voltage set to 3.3V. The microcontroller does not perform complex filtering internally; instead, it directly performs hardware conversion based on a linear proportional relationship. The specific conversion formula is as follows: in, This represents the final low-frequency response amplitude; This represents the dimensionless direct-sampled digital value read from the direct-sampling port; 4096 is the full-scale resolution constant of the 12-bit analog-to-digital converter. This represents a reference voltage of 3.3V. The system uses this as a basis for hardware mapping to directly obtain the real-time potential.

[0031] Furthermore, the hardware envelope detection port extracts the high-frequency envelope and quantifies the voltage drop amplitude of the high-frequency envelope as the carrier attenuation ratio, achieving pure hardware frequency band isolation without relying on pure software digital filtering. It can be understood that the hardware envelope detection port consists of a detector diode network and a resistor-capacitor (RC) low-pass network. After the feedback signal enters this port, the detector diode network rectifies the high-frequency oscillation signal, and the RC low-pass network filters out the center frequency component, outputting a high-frequency envelope DC analog signal reflecting the carrier energy fluctuations. Specifically, the RC low-pass network uses a first-order RC filter circuit with a cutoff frequency set between 10kHz and 20kHz. This cutoff frequency setting makes the RC time constant much larger than the high-frequency probe carrier period and much smaller than the low-frequency reference pulse period, thus enabling the smooth extraction of the high-frequency envelope in a purely hardware manner. The comparison and hold circuit obtains the voltage drop amplitude of the envelope and quantifies it as the carrier attenuation ratio. The specific quantization logic uses basic arithmetic operations: Carrier attenuation ratio = (Initial envelope reference voltage under static conditions - Currently acquired real-time envelope voltage) / Initial envelope reference voltage under static conditions × 100%. This logic is directly executed by the arithmetic logic unit inside the microcontroller to obtain the dimensionless percentage parameter.

[0032] In this embodiment, as Figure 4 As shown, the execution blocking terminal contains a trip holding coil and a hardware self-locking closed loop. After the mixed signal generating node outputs the disconnection control signal, the hardware self-locking closed loop uses a thyristor to maintain continuous conduction, forcing the trip holding coil to remain in the energized state. Specifically, the disconnection control signal is input as a trigger pulse signal to the thyristor control electrode in the hardware self-locking closed loop of the execution blocking terminal. After receiving the trigger pulse, the thyristor enters the conducting state, and its main circuit is connected in series in the drive circuit of the trip holding coil. The continuous conduction of the thyristor energizes the trip holding coil, pulling the main circuit breaker tripping mechanism to operate, thus maintaining the circuit in a physically disconnected state.

[0033] Furthermore, even if saboteurs perform a complete power cut and force a short-circuit to reconnect the power, the thyristor will be triggered to conduct again due to the extremely high surge change at the moment of abnormal power recovery, maintaining the physical blocking state and preventing power-off restart evasion behavior. It is understood that a differential triggering network is configured between the anode and control electrode of the thyristor. Specifically, the differential triggering network consists of a conventional first-order hardware differential circuit composed of a series high-voltage ceramic capacitor and a voltage divider resistor. Its RC parameters are configured so that the trigger current driving the thyristor control electrode is only output when an extreme abnormal arc surge with a transient voltage rise rate exceeding 500V / ms occurs on the power line, effectively filtering out grid voltage fluctuations, including those from normal closing. In terms of hardware selection and matching, this embodiment uses a micropower thyristor with a gate trigger current reference of 1mA. Based on the basic capacitor transient current formula... in, This represents the transient trigger current flowing through the high-voltage ceramic capacitor and injected into the control electrode of the thyristor; This indicates the nominal capacitance of a high-voltage ceramic capacitor. This indicates the rate of rise of transient voltage caused by extreme abnormal surges on the power line. (The last part is incomplete and likely refers to a specific technical term or concept.) The requirement is to detect extreme surges of 500V / ms and meet the transient trigger current requirement. Under physical conditions of 1mA or greater, reverse calculation and selection of capacitance. A standard 2200pF high-voltage ceramic capacitor, coupled with a 10kΩ voltage divider resistor, limits steady-state leakage current. Through the quantified matching of these basic components, precise triggering of malicious hard-connection surges can be achieved. If the system's external power supply is cut off and then illegally short-circuited and reconnected, the extreme voltage rise rate surge signal generated on the power line injects trigger current into the thyristor's control electrode through a differential triggering network. This causes the thyristor to re-trigger conduction the instant power is restored, and the trip holding coil is re-engaged, maintaining a blocking state in the physical circuit. Simultaneously, to meet the operational and maintenance requirements of normal on-site engineering implementation, the system is equipped with unlocking measures. A maintenance switch is connected in series on the thyristor's anode main circuit. During routine power supply or power outage repair, maintenance personnel can manually operate this maintenance switch according to the operating procedures to cut off the holding current flowing through the thyristor, forcing the thyristor out of the conduction self-locking state, achieving legal unlocking and equipment reset. To ensure that the thyristor can remain on after being triggered by an extreme surge, the trip holding coil needs to be matched with hardware parameters so that the steady-state pull-in current generated by its DC internal resistance under the system operating voltage is forced to be greater than the nominal holding current extreme value of the micropower thyristor. This pull-in current is usually set to be greater than 10mA to avoid the thyristor turning off automatically due to excessive load impedance.

[0034] In this embodiment, the mixed signal generation node compares the low-frequency response amplitude with the open-circuit reference threshold in real time. It is understood that a current-limiting bias resistor is provided in the input measurement circuit of the mixed signal generation node, and this current-limiting bias resistor and the carbon film resistor element constitute a DC voltage divider structure. In normal standby mode, the low-frequency response amplitude is always higher than the lowest potential determined by the current-limiting bias resistor; this lowest potential is the open-circuit reference threshold. The voltage comparator receives the open-circuit reference threshold and compares it with the real-time low-frequency response amplitude.

[0035] If the low-frequency response amplitude instantly drops to the reference zero potential without any change in the carrier attenuation ratio, the displacement sensing feedback network is determined to have been damaged by a wire cut, directly triggering the disconnection control signal. Specifically, when the physical circuit is cut, the DC voltage divider structure is open-circuited, and the low-frequency response amplitude drops to zero potential at a specific time point. Since the conductor breakage process is short, it does not cause a parametric jump in the contact surface distributed capacitance, so the carrier attenuation ratio remains unchanged. The voltage comparator detects a level jump below the open-circuit reference threshold, and the logic unit does not detect carrier attenuation, thus determining it as a wire cut and directly outputting the disconnection control signal. It should be noted that, considering the unavoidable common-mode interference and the operational amplifier's inherent offset voltage in industrial environments, the reference zero potential is not theoretically 0V in engineering implementation, but is defined as the low-frequency response amplitude dropping to within the hardware's underlying noise tolerance range. In this embodiment, this tolerance threshold is fixedly set to less than or equal to 0.05V.

[0036] In this embodiment, for the extremely slow failure condition of the micro hydraulic strut, the carrier attenuation ratio may be lower than the high-frequency carrier attenuation threshold. It is understood that the slow thrust loading results in a longer drift time for the distributed capacitance parameter at the contact surface between the metal hairspring and the carbon film resistor element, reducing the envelope attenuation amplitude of the high-frequency detection carrier. Consequently, the extracted carrier attenuation ratio is lower than the high-frequency carrier attenuation threshold, failing to trigger the pre-state flag.

[0037] To handle this operating condition, the mixed signal generation node samples multiple low-frequency response amplitudes at preset intervals and calculates the deviation slope between adjacent periods. Specifically, the timer inside the mixed signal generation node triggers the analog-to-digital converter to discretely sample the low-frequency response amplitudes at fixed time intervals. The difference between the current sampling point and the previous sampling point is calculated using a differential algorithm and divided by the preset period time to obtain the deviation slope.

[0038] If multiple consecutive deviation slopes are positive and the range is below the set fluctuation lower limit, it is determined that the door is being opened very slowly by a constant thrust, unaffected by the status flag, and the disconnection control signal is forcibly triggered. The system uses sliding counting engineering judgment logic to replace complex statistical calculations, with a preset period of 500 milliseconds. The deviation slope is represented by the voltage difference between adjacent samples. The set fluctuation lower limit is set to 1mV to 3mV. When the deviation slope is positive for 10 consecutive sampling periods, and the absolute value of the difference between the deviation slopes of any two adjacent periods (i.e., the range) is less than the set fluctuation lower limit, it indicates that the door is being subjected to a continuous and stable mechanical thrust, excluding random environmental fluctuations, and the disconnection control signal is directly triggered. Limited by the computing power of the basic microcontroller in the industrial field, the determination of the signal fluctuation dispersion can be achieved at low cost by evaluating whether the range is below the set fluctuation lower limit.

[0039] In this embodiment, drastic changes in ambient temperature and humidity can cause a natural drift in the distributed capacitance parameter of the contact surface. Specifically, ambient humidity alters the water molecule concentration in the gap between the contact surfaces, and ambient temperature changes the elastic modulus of the metal tentacles, leading to changes in the distributed capacitance parameter and the initial contact pressure, resulting in baseline drift of the high-frequency detection carrier amplitude.

[0040] Therefore, the hybrid signal generation node incorporates ambient temperature and humidity parameters to construct a dynamic compensation lookup table matrix. Specifically, the temperature and humidity sensing unit transmits real-time ambient temperature and relative humidity data to the hybrid signal generation node. The hybrid signal generation node's memory stores a multi-dimensional dynamic compensation lookup table matrix, which contains corresponding baseline correction coefficients.

[0041] The hybrid signal generation node retrieves the dynamic compensation lookup table matrix in real time based on the currently acquired environmental temperature and humidity parameters, dynamically adjusting or lowering the trigger threshold of the high-frequency carrier attenuation threshold to prevent feature misjudgment caused by severe weather. The lookup table matrix is ​​generated offline through enumeration testing in a high and low temperature humidity test chamber during the system finalization stage. The operating temperature is divided into two-dimensional discrete grids in 5°C increments and relative humidity in 10% increments. The background drift of the contact surface distributed capacitance under the environment of each grid node is measured and recorded. Based on this, the corresponding dimensionless correction coefficient is calculated and burned into the read-only memory. To adapt to the computational load of conventional microcontrollers, the calculation of the dimensionless correction coefficient does not rely on high-order polynomial fitting, but directly adopts the factory measured ratio method: the background capacitance calibration value under the standard factory environment of 25°C and 50% relative humidity is fixed as the numerator, and the measured capacitance value under each high and low temperature humidity grid node is used as the denominator. The simple division between the two is used as the correction coefficient for that environmental node, which is directly written into the lookup table matrix for retrieval. In actual operation and monitoring, the microcontroller reads the current discrete values ​​of the temperature and humidity sensor via the bus, directly uses these values ​​as address pointers to retrieve the corresponding correction coefficients from memory, and then multiplies them by the factory-calibrated high-frequency carrier attenuation threshold to complete the real-time update of the trigger threshold. It can be understood that the mixed-signal generation node reads the temperature and humidity data and interpolates the correction coefficients in the dynamic compensation lookup table matrix. These correction coefficients are then used to calculate the high-frequency carrier attenuation threshold, dynamically adjusting the trigger threshold parameters to compensate for the effects of environmental parameter drift. After reading the temperature and humidity data, the mixed-signal generation node retrieves the correction coefficients from the dynamic compensation lookup table matrix through nearest-neighbor addressing. To reduce the chip's computational load, the system does not introduce complex mathematical interpolation algorithms but instead uses nearest-neighbor rounding logic: if the current measured temperature is 23℃, the microcontroller automatically rounds it and associates it with the nearest 25℃ grid node address for data retrieval, using simple absolute matching to complete dynamic compensation.

[0042] In this embodiment, when the metering box is subjected to vibration interference from a heavy truck, the carrier attenuation ratio exhibits high-frequency sinusoidal oscillations, but the low-frequency response amplitude fluctuates symmetrically around the original macroscopic position. Specifically, mechanical vibration causes elastic vibration of the contact surface, resulting in periodic changes in the contact surface pressure, and the carrier attenuation ratio exhibits a high-frequency oscillating signal. Simultaneously, the low-frequency response amplitude fluctuates symmetrically around the static baseline.

[0043] Furthermore, the hybrid signal generation node extracts the symmetrical extreme values ​​of the low-frequency response amplitude. If none of the symmetrical extreme values ​​exceed the displacement alarm threshold and the oscillation mean does not shift, it is determined to be environmental vibration interference, and the recorded status marker is actively cleared. Specifically, the hybrid signal generation node extracts the peak and trough values ​​of the low-frequency response amplitude, calculates the difference between the extreme values ​​and the baseline, and the oscillation mean of the waveform. If the extreme values ​​are within the displacement alarm threshold and the oscillation mean does not shift, the fluctuation is determined to be environmental vibration interference, the register is actively reset, and the locked state of the potential damage monitoring stage is cleared. The specific criterion for determining that the oscillation mean does not shift is: the absolute value of the difference between the oscillation mean calculated by the microcontroller and the initial static baseline is less than 5% of the displacement alarm threshold, allowing for minor errors caused by normal background noise.

[0044] In this embodiment, before the physical circuit is disconnected due to damage, the hybrid signal generation node stores the carrier attenuation ratio and the low-frequency response amplitude captured moment before the power failure into a non-volatile ferroelectric storage module. Specifically, the system sets 70% to 75% of the system's rated operating voltage as an undervoltage threshold. When the input level drops to this undervoltage threshold, the power management unit issues a power-down interrupt, and the hybrid signal generation node writes the carrier attenuation ratio, low-frequency response amplitude sequence, and status word data stored in the random access memory into the non-volatile ferroelectric storage module.

[0045] To ensure sufficient residual power for the hardware, an electrolytic capacitor with a capacity ranging from 470μF to 1000μF is connected in parallel at the power input of the mixed signal generation node. When the external power supply is completely interrupted, this electrolytic capacitor, relying on its own discharge, can provide a millisecond-level support power supply window under the low current load of this system. The non-volatile ferroelectric memory module itself has microsecond-level high-speed write characteristics. It can be understood that the non-volatile ferroelectric memory module utilizes the ample millisecond-level support power supply window provided by the electrolytic capacitor discharge to store data packets into the storage unit within its extremely short microsecond-level time, thus ensuring the preservation of macroscopic and microscopic electrical signal parameters at the moment of destruction before the power supply is completely exhausted. This provides reliable underlying waveform data for subsequent tracing of the physical process of destruction.

[0046] This embodiment also provides a method for a tamper-proof electrical monitoring circuit for metering boxes based on mechanical displacement analog quantity capture. Using the tamper-proof electrical monitoring circuit system for metering boxes based on mechanical displacement analog quantity capture described in the above embodiment, the main flow of the method is as follows: Figure 5 As shown, it includes the following steps: A low-frequency reference pulse superimposed with a high-frequency probe carrier is generated by a hybrid signal generation node and continuously injected into the displacement sensing feedback network. Specifically, the hybrid signal generation node outputs a low-frequency reference pulse and generates a high-frequency probe carrier, and the two signals are superimposed and injected into the displacement sensing feedback network.

[0047] The displacement sensing feedback network alters the response amplitude of the low-frequency reference pulse based on the macroscopic opening and closing amplitude of the metering box door, while simultaneously attenuating the high-frequency detection carrier based on the microscopic contact impedance change of the metering box door under stress. Specifically, the macroscopic displacement of the door structure is converted into a resistance change on the carbon film resistor structure, modulating the potential of the low-frequency pulse; the stress on the door causes a change in microscopic contact impedance, triggering a sudden change in distributed capacitance and capacitive reactance, thus attenuating the high-frequency detection carrier.

[0048] The hybrid signal generating node receives the feedback signal, separates the low-frequency response amplitude and carrier attenuation ratio, and performs anti-sabotage blocking steps: The carrier attenuation ratio is continuously compared with a preset high-frequency carrier attenuation threshold. Specifically, the mixed signal generation node compares the carrier attenuation ratio value with the high-frequency carrier attenuation threshold according to the sampling period.

[0049] When the carrier attenuation ratio exceeds the high-frequency carrier attenuation threshold, the system is determined to enter the potential damage monitoring phase and a status flag is generated. Specifically, when the carrier attenuation ratio is greater than the high-frequency carrier attenuation threshold, an abnormal mechanical contact is determined, a status flag is set in the register, and a status tracking timeout is enabled.

[0050] If, within the state tracking time limit following the detection of the state marker, the low-frequency response amplitude exceeds the displacement alarm threshold, it is determined that actual physical damage has occurred, and a disconnection control signal is output to the execution blocking terminal. Specifically, within the state tracking time limit, if the change in the low-frequency response amplitude exceeds the displacement alarm threshold, the system sends a trigger signal to the execution blocking terminal to disconnect the main electrical circuit.

[0051] If the low-frequency response amplitude slowly exceeds the displacement alarm threshold, but the status marker is not detected during the potential damage monitoring stage, it is determined to be a natural environmental thermal expansion and contraction offset, and the disconnection control signal is blocked. Specifically, if the low-frequency response amplitude exceeds the tolerance limit but the status marker is not found in the register, the system determines it to be an environmental temperature drift and blocks the disconnection control signal.

[0052] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A tamper-proof electrical monitoring circuit system for a metering box based on the capture of analog mechanical displacement, characterized in that, This includes a mixed signal generation node, a displacement sensing feedback network, and an execution blocking terminal; The hybrid signal generation node generates a low-frequency reference pulse superimposed with a high-frequency probe carrier and continuously injects it into the displacement sensing feedback network. The displacement sensing feedback network changes the response amplitude of the low-frequency reference pulse based on the macroscopic opening and closing amplitude of the metering box door, and attenuates the high-frequency detection carrier based on the microscopic contact impedance change of the metering box door when it is forced. The hybrid signal generating node receives the feedback signal, separates the low-frequency response amplitude and carrier attenuation ratio, and performs anti-sabotage blocking steps: The carrier attenuation ratio is continuously compared with a preset high-frequency carrier attenuation threshold. When the carrier attenuation ratio exceeds the high-frequency carrier attenuation threshold, it is determined that the potential damage monitoring stage has been entered and a status mark has been generated. If the low-frequency response amplitude exceeds the displacement alarm threshold within the state tracking time limit after the state flag is detected, it is determined that a real physical damage has occurred, and a disconnection control signal is output to the execution blocking terminal. If the low-frequency response amplitude slowly exceeds the displacement alarm threshold, but the status marker is not detected during the potential damage monitoring stage, it is determined to be a natural environmental thermal expansion and contraction offset, and the disconnection control signal is blocked.

2. The metering box anti-vandalism electrical monitoring circuit system based on mechanical displacement analog quantity capture according to claim 1, characterized in that, The displacement sensing feedback network is connected in series with a carbon film resistor element and a metal hairspring contact. The metal hairspring contacts abut against the surface of the carbon film resistor element; When the metering box door is forced to move, the compression state between the metal hairspring and the carbon film resistor element undergoes a microscopic change, causing a jump in the capacitance parameter of the contact surface. The abrupt change in the capacitance parameter of the contact surface constitutes the physical cause of the attenuation of the high-frequency probe carrier.

3. The metering box anti-vandalism electrical monitoring circuit system based on mechanical displacement analog quantity capture according to claim 1, characterized in that, The mixed signal generation node is equipped with a hardware envelope detection port and a direct sampling port. The feedback signal is simultaneously sent to the hardware envelope detector port and the direct sampling port; The direct sampling port reads the long-period level and converts it into the low-frequency response amplitude; The hardware envelope detection port extracts the high-frequency envelope and quantifies the voltage drop amplitude of the high-frequency envelope as the carrier attenuation ratio, achieving pure hardware frequency band isolation without relying on pure software digital filtering.

4. The metering box anti-vandalism electrical monitoring circuit system based on mechanical displacement analog quantity capture according to claim 1, characterized in that, The execution blocking terminal contains a tripping holding coil and a hardware self-locking closed loop; After the mixed signal generating node outputs the disconnection control signal, the hardware self-locking closed loop uses a thyristor to complete continuous conduction, forcing the trip holding coil to remain in the energized state. Even if saboteurs perform a complete power cut and force a short circuit to reconnect the power, the thyristor will be triggered to conduct again due to the extremely high surge change at the moment the abnormal power supply recovers, maintaining the physical blocking state and preventing power-off restart evasion behavior. A maintenance switch is connected in series on the anode main circuit of the thyristor. During normal power supply or power outage maintenance and restoration, it allows manual operation to cut off the holding current flowing through the thyristor, forcing the thyristor to exit the conduction self-locking state, thereby realizing legal unlocking and equipment reset.

5. The metering box anti-vandalism electrical monitoring circuit system based on mechanical displacement analog quantity capture according to claim 1, characterized in that, The mixed signal generation node compares the low-frequency response amplitude with the open-circuit reference threshold in real time; In normal standby mode, the amplitude of the low-frequency response is always higher than the lowest potential determined by the current-limiting bias resistor; If the low-frequency response amplitude drops instantaneously to the reference zero potential without any change in the carrier attenuation ratio, it is determined that the displacement sensing feedback network has been damaged by wire cutting and circuit breaking, and the disconnection control signal is directly triggered.

6. The metering box anti-vandalism electrical monitoring circuit system based on mechanical displacement analog quantity capture according to claim 1, characterized in that, For the extremely slow failure condition of the miniature hydraulic strut, the carrier attenuation ratio may be lower than the high-frequency carrier attenuation threshold. The mixed signal generation node extracts multiple low-frequency response amplitudes at equal intervals according to a preset period, and calculates the deviation slope between adjacent periods; If multiple consecutive deviations are positive and the range is below the set fluctuation limit, it is determined that the device is subjected to a constant thrust and opens very slowly, unaffected by the status flag, and the disconnection control signal is forcibly triggered.

7. The metering box anti-vandalism electrical monitoring circuit system based on mechanical displacement analog quantity capture according to claim 1, characterized in that, Dramatic changes in external temperature and humidity can cause the distributed capacitance parameter of the contact surface to drift naturally. The hybrid signal generation node incorporates environmental temperature and humidity parameters to construct a dynamic compensation lookup table matrix. The hybrid signal generation node retrieves the dynamic compensation lookup table matrix in real time based on the currently acquired environmental temperature and humidity parameters, and dynamically adjusts or lowers the trigger threshold of the high-frequency carrier attenuation threshold to prevent feature misjudgment caused by severe weather.

8. The metering box anti-vandalism electrical monitoring circuit system based on mechanical displacement analog quantity capture according to claim 1, characterized in that, When the metering box is subjected to vibration interference from a heavy truck, the carrier attenuation ratio exhibits high-frequency sinusoidal oscillation, but the low-frequency response amplitude fluctuates symmetrically around the original macroscopic position. The mixed signal generating node extracts the symmetrical extreme values ​​of the low-frequency response amplitude. If none of the symmetrical extreme values ​​exceed the displacement alarm threshold and the oscillation mean does not shift, it is determined to be environmental vibration interference, and the recorded status markers are actively cleared.

9. The metering box anti-vandalism electrical monitoring circuit system based on mechanical displacement analog quantity capture according to claim 1, characterized in that, Before the physical circuit is disconnected due to damage, the mixed signal generation node stores the carrier attenuation ratio and the low-frequency response amplitude captured at the moment before the power failure into a non-volatile ferroelectric storage module. An energy storage electrolytic capacitor is connected in parallel at the power input terminal of the mixed signal generation node, with a capacitance set to 470μF to 1000μF. The non-volatile ferroelectric memory module has microsecond-level high-speed write characteristics. When the external power supply is completely interrupted, the energy storage electrolytic capacitor provides a millisecond-level support power supply window by discharging itself. The non-volatile ferroelectric memory module uses this millisecond-level support power supply window to complete data solidification, providing reliable underlying waveform data for subsequent tracing of the physical process of destruction.

10. A method for preventing damage to electrical monitoring circuits of metering boxes based on the capture of analog mechanical displacement, characterized in that, The metering box anti-vandal electrical monitoring circuit system based on mechanical displacement analog capture as described in any one of claims 1 to 9 includes the following steps: A low-frequency reference pulse superimposed with a high-frequency probe carrier is generated using a hybrid signal generation node and continuously injected into the displacement sensing feedback network. The displacement sensing feedback network is used to change the response amplitude of the low-frequency reference pulse based on the macroscopic opening and closing amplitude of the metering box door, while the high-frequency detection carrier is attenuated based on the microscopic contact impedance change of the metering box door when it is forced. The hybrid signal generating node receives the feedback signal, separates the low-frequency response amplitude and carrier attenuation ratio, and performs anti-sabotage blocking steps: The carrier attenuation ratio is continuously compared with a preset high-frequency carrier attenuation threshold. When the carrier attenuation ratio exceeds the high-frequency carrier attenuation threshold, it is determined that the potential damage monitoring stage has been entered and a status mark has been generated. If the low-frequency response amplitude exceeds the displacement alarm threshold within the state tracking time limit after the state flag is detected, it is determined that a real physical damage has occurred, and a disconnection control signal is output to the execution blocking terminal. If the low-frequency response amplitude slowly exceeds the displacement alarm threshold, but the status marker is not detected during the potential damage monitoring stage, it is determined to be a natural environmental thermal expansion and contraction offset, and the disconnection control signal is blocked.

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