Non-metallic electric energy metering box with one code dual-purpose anti-theft electricity verification

Abstract

The application discloses a non-metallic electric energy metering box with one-code dual-purpose anti-theft electricity verification, which comprises a non-metallic box body, a one-code dual-purpose verification module, a passive external monitoring unit, a physical locking isolation unit and an active reverse verification unit. The box body is made of insulating composite material, and a distributed electromagnetic coupling array is pre-embedded in the wall. The unique identity code of the verification module is used as a legal authentication certificate of the equipment in the first mode, and is used as an anti-theft electricity situation awareness key after being transformed by an algorithm in the second mode. The passive external monitoring unit passively collects running state characteristics through non-contact electromagnetic field coupling in the independent domain outside the box body. The physical locking isolation unit triggers irreversible locking when the characteristics deviate from the threshold. The active reverse verification unit sends a time-varying sequence challenge from the metering end to the power consumption end after locking. The application solves the technical problem of anti-theft electricity of the non-metallic electric energy metering box.

Description

Technical Field

[0001] This invention relates to the field of power metering equipment security protection technology, specifically to a power metering box for preventing electricity theft that uses a non-metallic composite material enclosure and integrates passive electromagnetic monitoring and active reverse verification mechanisms. It belongs to the cross-technical field of power Internet of Things information security and smart grid terminal equipment. Background Technology

[0002] As a critical infrastructure at the end of the power grid, the electricity metering box undertakes the core functions of electricity metering, data acquisition, and transmission. Its metering accuracy and operational safety are directly related to the power grid's operational efficiency and the maintenance of electricity consumption order. With the in-depth advancement of smart grid construction, the electricity metering box has evolved from a simple metering instrument into an intelligent terminal node integrating metering, communication, and control. Its security protection requirements have also expanded from traditional physical anti-theft to multi-dimensional, three-dimensional protection covering the physical layer, electromagnetic layer, and protocol layer.

[0003] Currently, the main material used for electricity metering boxes is sheet metal, utilizing the electromagnetic shielding properties of metal to achieve electromagnetic compatibility protection for the internal circuits. However, metal boxes have inherent drawbacks such as susceptibility to corrosion, heavy weight, poor insulation, and high processing costs. Furthermore, in actual operation, the fully enclosed shielding characteristics of metal boxes actually provide convenient black-box operations for electricity thieves, as external monitoring methods cannot penetrate the metal shielding layer to obtain internal operating status information, making anomaly detection methods based on electromagnetic characteristic analysis difficult to implement. In recent years, non-metallic composite materials have been gradually applied in the field of electricity metering boxes due to their excellent insulation properties, corrosion resistance, and lightweight characteristics. However, the electromagnetic transparency of non-metallic materials also brings a dual problem: easy leakage of internal electromagnetic signals and easy intrusion of external electromagnetic interference. Traditional electromagnetic shielding approaches cannot be directly applied.

[0004] In terms of anti-electricity theft technology, existing solutions mainly focus on three technical approaches: first, encryption authentication technology based on security modules embedded in metering chips, which protects data integrity through hardware security units; second, electricity consumption behavior analysis technology based on abnormal current and voltage characteristics, which identifies electricity theft by comparing load curves with historical patterns; and third, mechanical protection technology based on physical sealing and cover opening detection, which detects cabinet opening events through contact switches or photosensitive sensors. All of these technical approaches have significant limitations: encryption authentication technology focuses on data transmission security and lacks effective detection of physical-layer electricity theft (such as bypass shunting and strong magnetic interference); electricity consumption behavior analysis is a post-event traceability mechanism with poor real-time performance and is easily affected by changes in load characteristics; and mechanical protection technology only targets physical opening events and is powerless against non-intrusive electromagnetic electricity theft methods.

[0005] More critically, existing anti-theft technologies generally employ a closed-loop architecture of active detection and feedback control. This means the system actively sends detection signals to the protected object and determines the presence of anomalies based on response characteristics. This architecture has inherent flaws: the active detection signals themselves can become entry points for electricity thieves, the feedback control link can be hijacked and exploited, and frequent active queries increase system power consumption and communication load. Furthermore, key management in existing technologies often uses static pre-setting or remote updates, lacking a dynamic binding relationship between keys and device operating status and the physical environment of the power grid. Once the keys are extracted or intercepted, the entire protection system becomes ineffective.

[0006] For non-metallic energy metering boxes, existing technologies have not yet resolved the following core contradictions: On the one hand, the electromagnetic transparency of non-metallic materials makes internal signal leakage possible, theoretically allowing for external monitoring; on the other hand, this transparency also exacerbates interference from the external electromagnetic environment on internal metering, rendering traditional metal-based shielding protection methods completely ineffective. How to transform the electromagnetic transparency of non-metallic materials from a disadvantage into a usable characteristic, achieving a monitorable yet inaccessible protective effect, is currently a technological bottleneck facing the industry.

[0007] Therefore, the field of electricity metering urgently needs an anti-theft technology solution that can overcome the electromagnetic transparency defects of non-metallic materials, get rid of the dependence on active detection feedback, and achieve strong binding between the key and the physical environment, so as to solve common technical problems in existing technologies such as insufficient passive monitoring capabilities, delayed physical isolation response, and static key fixation. Summary of the Invention

[0008] The purpose of this invention is to provide a non-metallic energy metering box with dual-use anti-theft verification code. It solves the anti-theft technology problem of non-metallic energy metering boxes by using passive electromagnetic monitoring of an independent domain outside the box, physical irreversible interlocking, reverse verification initiated by the metering end, and a dual-use key transformation mechanism.

[0009] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0010] A non-metallic energy metering box with dual-use anti-theft verification code is characterized by comprising a non-metallic box body, a dual-use verification module, a passive external monitoring unit, a physical interlocking isolation unit, and an active reverse verification unit. The non-metallic box body is made of insulating composite material, and a distributed electromagnetic coupling array is pre-embedded within the box wall. The dual-use verification module is equipped with a unique identification code, which serves as a device legitimacy authentication credential in the first verification mode and, after algorithmic transformation, serves as an anti-theft situational awareness key in the second verification mode. The passive external monitoring unit is located in an independently powered isolated monitoring area outside the box, passively collecting the operational characteristics of the metering unit inside the box through non-contact electromagnetic field coupling. This passive collection does not include… This includes any query or control commands actively sent to the metering unit, and silent monitoring of the electromagnetic radiation characteristics on the surface of the enclosure; the physical interlocking isolation unit is linked with the passive external monitoring unit. When the detected operating characteristics deviate from the preset baseline threshold, the physical interlocking logic is triggered, irreversibly cutting off the logical path between the metering unit and the external electrical interface, and simultaneously closing the second verification mode entry of the dual-code verification module; the active reverse verification unit is activated after the physical interlocking isolation unit is triggered, and the metering end actively sends a verification challenge to the power user. The verification challenge includes a time-varying sequence generated based on the second verification mode key of the dual-code verification module. The power user must send a response back through an independent physical channel within a specified time window, otherwise an electricity theft alarm will be triggered.

[0011] Furthermore, the passive external monitoring unit includes a passive electromagnetic induction coil group, a silent comparison engine, and a dynamic threshold determiner. The passive electromagnetic induction coil group consists of at least three sets of passive electromagnetic induction coils arranged in a spatial triangular distribution, embedded in a concealed groove in the non-metallic frame outside the enclosure. The coils are not physically connected to any electrical circuit inside the enclosure. The passive electromagnetic induction coil group receives the spatial electromagnetic radiation signal leaked from the electrical circuit inside the enclosure and performs spectral decomposition processing on the spatial electromagnetic radiation signal to obtain the fundamental frequency component, harmonic group component, and transient pulse component, and sends them to the silent comparison engine. The silent comparison engine receives the fundamental frequency component, harmonic group component, and transient pulse component, performs mode distance calculation processing on the data to obtain a real-time mode distance value, and sends it to the dynamic threshold determiner. The dynamic threshold determiner receives the real-time mode distance value and performs threshold range out-of-bounds judgment processing on the data to obtain an out-of-bounds judgment result. When the out-of-bounds judgment result is that the threshold range is exceeded, the physical locking isolation unit is activated.

[0012] Furthermore, the physical interlocking isolation unit includes a one-time fusible barrier and a logic channel blocker. The one-time fusible barrier is connected in series between the metering unit and the external electrical interface, and is used to irreversibly cut off the physical electrical path between the metering unit and the external electrical interface after being triggered. The logic channel blocker is linked to the one-time fusible barrier and is used to perform a logic blocking action immediately upon or after the one-time fusible barrier is triggered. The logic blocking action includes transferring the second verification mode key of the dual-code verification module to an independent security domain outside the enclosure for storage through an emergency optical transmission channel, so as to disable the verification logic inside the enclosure. The physical cutting action of the one-time fusible barrier and the logic blocking action of the logic channel blocker together constitute a double interlocking of the metering unit. The double interlocking can only be released by physically replacing the one-time fusible barrier and by remote authorization through the external independent security domain.

[0013] Furthermore, the emergency optical transmission channel includes a pre-embedded structural fiber and a mechanical optical switch. The pre-embedded structural fiber is embedded in the structural layer of the non-metallic composite material during the manufacture of the enclosure, with no exposed interfaces on its surface. During normal communication within the enclosure, the pre-embedded structural fiber is in a physically disconnected state, maintained by opaque optical isolation plugs formed at both ends of the pre-embedded structural fiber through a heat-sealing process. The mechanical optical switch is mechanically coupled to the pre-embedded structural fiber and is used to receive the trigger signal from the logic channel closure device. Upon receiving the trigger signal, it performs a one-time optical path switching action. The one-time optical path switching action includes driving the pre-embedded structural fiber from the physically disconnected state to a direct optical coupling state to form a one-time optical transmission link from the inside of the enclosure to the external security domain. The mechanical optical switch drives the pre-embedded structural fiber through irreversible mechanical deformation. After the pre-embedded structural fiber is switched to the direct optical coupling state, it cannot be restored to the physically disconnected state by the mechanical optical switch.

[0014] Furthermore, the active reverse verification unit includes a challenge generator, a heterogeneous dual-channel transmitter, a cross-pass receiver, and a time window controller. The challenge generator receives the second verification mode key of the dual-use verification module and the instantaneous phase sampling value of the current power grid frequency, and performs time-varying sequence generation processing on these two types of data to obtain a single-time timeliness verification challenge code, which is then sent to the heterogeneous dual-channel transmitter. The heterogeneous dual-channel transmitter performs parallel power line carrier modulation and radio frequency modulation processing on the single-time timeliness verification challenge code to obtain dual heterogeneous challenge signals, which are then transmitted to the power user through the power line carrier channel and the radio frequency channel, respectively. The cross-pass receiver and the time window controller are set in a timing linkage, and the time window controller is configured in the challenge generation... The device generates a challenge code and starts a countdown simultaneously, outputting a receive enable signal to the cross-backhaul receiver during the countdown. During the effective period of the receive enable signal, the cross-backhaul receiver receives a response signal sent by the power user through a cross-backhaul channel different from the receiving channel, performs response code consistency comparison and response timing compliance judgment, and obtains a response judgment result. The countdown time limit set by the time window controller is 300ms, which is shorter than the signal transfer and retransmission delay of conventional electricity theft devices. When the countdown reaches zero, the time window controller cancels the receive enable signal, and responses received by the cross-backhaul receiver during the period when the receive enable signal is invalid are directly judged as invalid. When the response judgment result is not a valid response, an electricity theft alarm is triggered.

[0015] Furthermore, the non-metallic energy metering box also includes a simulated sensor node array, which consists of multiple simulated sensor nodes arranged in non-functional areas on the surface of the box. These non-functional areas are the remaining areas of the box surface excluding the functional areas, including the top edge, side reinforcing ribs, and bottom support feet. The functional areas are the necessary areas for operation and maintenance, housing the passive electromagnetic induction coil group's lead-out terminals, communication interface, and status indicator lights of the passive external monitoring unit. The simulated sensor nodes appear identical to the lead-out terminals of the passive electromagnetic induction coil group, but are solid structures filled with epoxy resin, lacking any electronic components, electrical wiring, or magnetic core, and therefore do not possess actual monitoring functions. The node surface is a decorative cover plate stamped from a thin stainless steel sheet. The back of the cover plate has no solder pads, leads, or conductive coating, and is fixed to the box surface with M3 stainless steel screws. The screw depth is the same as that of the actual monitoring nodes, making it impossible for electricity thieves to determine authenticity based on appearance or screw depth, thus increasing the detection difficulty and attack cost for electricity thieves.

[0016] Furthermore, the insulating composite material of the non-metallic enclosure body has a gradient distribution characteristic of dielectric constant. The enclosure wall is composed of an outer low-dielectric-constant protective layer, a middle high-dielectric-constant coupling layer, and an inner low-dielectric-constant isolation layer; the thickness ratio of the three layers is 1:2:1. The dielectric constant εr of the outer low-dielectric-constant protective layer is 3.0-3.5, the dielectric constant εr of the middle high-dielectric-constant coupling layer is 12.0-13.0, and the dielectric constant εr of the inner low-dielectric-constant isolation layer is 3.2-3.8. The middle high-dielectric-constant coupling layer is composed of barium titanate ceramic powder uniformly dispersed in an epoxy resin matrix. The volume fraction of the barium titanate ceramic powder is 35%-45%, the particle size is 5-20μm, and after surface modification with a silane coupling agent, it forms an insulating interface with the epoxy resin matrix, with a volume resistivity ≥10^14. The high dielectric constant of the middle high dielectric constant coupling layer enhances the energy concentration of the internal leakage electromagnetic field in the middle layer, improving the coupling efficiency of the passive electromagnetic induction coil of the passive external monitoring unit to the internal signal; at the same time, the high volume resistivity of the middle layer blocks the conduction path of DC and power frequency current, preventing short circuits or bypasses when external conductors directly contact the internal circuit; the three-layer structure is cured in one step during the molding process, and the interlayer forms an interface transition region through molecular chain entanglement and chemical bonding, the thickness of which is 0.1-0.3 mm.

[0017] Furthermore, the algorithm transformation of the dual-code verification module includes a first verification mode and a second verification mode. In the first verification mode, the identifier code is used to generate a 256-bit device fingerprint using the SM3 hash algorithm. The device fingerprint is stored in the read-only storage area of ​​the local security chip in the enclosure in the form of an immutable fuse array for verifying the legality of the device identity. In the second verification mode, the identifier code is used to generate an anti-electricity theft situational awareness key through chaotic mapping transformation. The chaotic mapping transformation receives the identifier code and the instantaneous sample value of the power grid frequency, and performs one-way chaotic mapping calculation processing on these two types of data to obtain the verification key.

[0018] Furthermore, the present invention also includes a unidirectional optical isolation channel, a heartbeat frame generator, and a consistency comparator; the unidirectional optical isolation channel is used to connect the internal metering unit of the enclosure with the external independent monitoring domain, allowing only unidirectional signal transmission from the inside to the outside, blocking any signal injection from the outside to the inside; the heartbeat frame generator is set in the internal metering unit of the enclosure, receives the status parameter set of the internal operating status, and performs compressed fingerprint generation processing on the status parameter set to obtain an unforgeable heartbeat frame, which is sent to the external monitoring domain through the unidirectional optical isolation channel; the consistency comparator is used to receive the external electromagnetic features collected by the passive external monitoring unit and the internal electromagnetic features after decompression and restoration of the compressed fingerprint in the heartbeat frame, and performs consistency deviation calculation processing on these two types of data to obtain the consistency judgment result; when the consistency judgment result is that the external features are normal but the internal status is abnormal, an electricity theft alarm is triggered.

[0019] Furthermore, the non-metallic energy metering box adopts a layered independent defense architecture, which includes a contact physical defense layer and a non-contact electromagnetic defense layer. The contact physical defense layer consists of a physical locking isolation unit, used to irreversibly disconnect the physical path between the metering unit and the external electrical interface against physical electricity theft that directly contacts the box. The non-contact electromagnetic defense layer is executed collaboratively by a passive external monitoring unit and an active reverse verification unit, used to perform passive electromagnetic monitoring and active reverse verification against electromagnetic electricity theft in the area surrounding the box. There is no control coupling between the contact physical defense layer and the non-contact electromagnetic defense layer. The triggering of the contact physical defense layer is directly driven by the boundary judgment result of the passive external monitoring unit, and does not depend on the verification result confirmation of the active reverse verification unit in the non-contact electromagnetic defense layer. Changes in the operating state of the non-contact electromagnetic defense layer do not affect the triggering response timing of the contact physical defense layer. The absence of control coupling between the contact-type physical defense layer and the non-contact electromagnetic defense layer is specifically manifested in the fact that they do not share electrical circuits, communication buses, or trigger signal sources, and each is powered independently.

[0020] The beneficial effects of this invention are:

[0021] Traditional metal enclosures rely on electromagnetic shielding for protection, but this shielding characteristic also hinders external perception of the internal operating status. This invention, through a gradient distribution of the dielectric constant of the enclosure walls, transforms the electromagnetic transparency of non-metallic materials into a penetrable monitoring advantage. This allows external passive coils to couple with the internal leakage electromagnetic field, while insulation properties prevent direct contact with external conductors, achieving a monitorable but inaccessible physical isolation effect. The passive external monitoring unit of this invention uses a high-impedance passive coil group, with received power controlled below -60dBm, ensuring that the monitoring process does not create detectable load disturbances to the internal circuitry. This achieves the concealment and security of passive monitoring. Compared with existing active query mechanisms, passive monitoring does not send any excitation signals, eliminating the possibility of active detection signals being used or circumvented by electricity thieves, achieving true silent monitoring. The one-time fuse-type isolation barrier of this invention requires physical replacement after triggering to restore, eliminating the possibility of remote reset or software bypass recovery. The logic channel sealer transfers the verification key to the external security domain through an emergency optical transmission channel, causing the enclosure to completely lose its verification capability in a locked state, forming a security situation of internal failure and external control.

[0022] The dual-use verification module of this invention binds the identification code to the instantaneous sampled value of the power grid frequency through chaotic mapping transformation. The generated verification key changes with the real-time state of the power grid, achieving a strong binding between the key and the physical state of the power grid. Since the power grid frequency is constrained by the overall power generation load balance, it is unpredictable and uncopyable, making it impossible to independently calculate or replay the verification key outside the actual power grid environment. The active reverse verification unit sends challenge codes in parallel through heterogeneous dual channels and requires cross-transmission of responses, while setting a response time limit shorter than the signal storage and retransmission delay. This design provides temporal suppression for forwarding-type electricity theft devices, preventing them from completing the receive-store-forward attack process.

[0023] The pseudo-metering pulse transmitter of this invention emits a pseudo-signal encoded with an identity watermark into external space. A surrounding electromagnetic activity detector extracts the watermark features from the response signal to identify whether there is amplification, forwarding, or tampering activity targeting the pseudo-signal. This mechanism can expose the probe's intent and attack capability before the electricity thief actually attacks the real metering circuit. The virtual metering circuit of this invention is not physically connected to the power grid, but it has electromagnetic scattering characteristics similar to the real circuit. When an external verification request is incorrectly directed to the virtual metering point, the system can determine that illegal probe activity exists. As a honeypot node, the virtual metering circuit can induce electricity thieves to reveal their attack intent while simultaneously protecting the security of the real metering circuit.

[0024] The timing evidence recorder of this invention begins recording abnormal electromagnetic feature sequences before the lockout is triggered, and ensures timing integrity through timestamp marking; the false command decoy releaser releases a false reset command after the lockout is triggered, and if the power user responds, it proves the existence of an illegal control device, and the response process is fully recorded as judicial evidence data; the evidence data is uploaded in real time through an emergency optical transmission channel to prevent local destruction.

[0025] The simulated sensor node array of this invention is visually identical to real nodes but lacks monitoring capabilities. The staggered layout algorithm prevents electricity thieves from distinguishing between real and fake nodes through simple detection, forcing them to attack or evade all nodes, significantly increasing the time cost and exposure risk of electricity theft. The dynamic threshold generator of this invention generates a judgment boundary that adaptively drifts with environmental conditions through boundary fusion calculations using a historical electricity theft feature pattern library and an environmental stress mapping table. This mechanism effectively distinguishes between normal offsets caused by environmental factors and abnormal abrupt changes caused by electricity theft, reducing the false alarm rate due to temperature, humidity, and vibration variations.

[0026] The power consumption disturbance controller of this invention actively reduces the power consumption of non-core functions and alters the electromagnetic radiation characteristics of the enclosure when a slight anomaly is detected. If an electricity thief adjusts their electricity theft strategy based on these characteristics, their adjustment will be captured by a fake metering pulse transmitter, thus exposing their intent to steal electricity without triggering physical blocking. The one-way heartbeat verification mechanism of this invention can detect deep-seated electricity theft patterns where "external characteristics are normal but internal state is abnormal" by comparing the consistency between internal heartbeat frames and external electromagnetic characteristics. The one-way optical isolation channel ensures that the heartbeat frame cannot be forged from the outside, forming a two-way verification closed loop of "internal authenticity and external verification".

[0027] In this invention, there is no control coupling between the contact-based physical defense layer and the non-contact electromagnetic defense layer, and near-layer triggering does not depend on far-layer confirmation. This architecture ensures that physical blocking can still be triggered independently even if the communication link is interfered with or damaged, avoiding cascading failures between layers. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the system deployment of the non-metallic energy metering box of the present invention;

[0029] Figure 2 This is a flowchart of the signal processing of the passive external monitoring unit of the present invention;

[0030] Figure 3 This is a schematic diagram of the physical interlocking isolation unit and emergency optical transmission channel of the present invention;

[0031] Figure 4 This is a challenge-response timing diagram of the active reverse verification unit of this invention;

[0032] Figure 5This is a flowchart of the algorithm transformation of the dual-use verification module of the present invention;

[0033] Figure 6 This is a logical diagram of the layered independent defense architecture of this invention. Detailed Implementation

[0034] To facilitate understanding of the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the invention and should not be considered as specific limitations thereof.

[0035] In the following description of the embodiments, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of this application with unnecessary detail.

[0036] It should be understood that, when used in this specification and the appended claims, the term "comprising" indicates the presence of a described feature, integral, step, operation, element, and / or component, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or collections thereof. It should also be understood that, as used in this specification and the appended claims, the term "and / or" refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0037] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0038] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance. References to "one embodiment" or "some embodiments" in this application mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof all mean "including but not limited to," unless otherwise specifically emphasized.

[0039] Example 1: System Example

[0040] Figure 1 This paper illustrates a typical deployment method of the non-metallic energy metering box of the present invention in a residential power distribution scenario.

[0041] 1.1 Structural Implementation of the Non-metallic Box Body

[0042] The non-metallic enclosure is molded from glass fiber reinforced unsaturated polyester composite material. The enclosure wall is 8mm thick and consists of three layers: the outer layer (101a) is a low-dielectric-constant protective layer with a dielectric constant εr = 3.2 and a thickness of 2mm, containing an added UV shielding agent; the middle layer (101b) is a high-dielectric-constant coupling layer with a dielectric constant εr = 12.5 and a thickness of 4mm, incorporating barium titanate ceramic powder; and the inner layer (101c) is a low-dielectric-constant isolation layer with a dielectric constant εr = 3.5 and a thickness of 2mm. The three layers are formed in a single molding process, with chemical bonds formed at the interfaces.

[0043] The distributed electromagnetic coupling array embedded within the enclosure wall consists of 12 sets of passive electromagnetic induction coils, arranged in four spatial triangular arrays on the top, bottom, left, and right sides of the enclosure. Each triangular array has a side length of 15cm. The coils are wound with 200 turns of 0.15mm enameled wire, with a manganese-zinc ferrite core, an inductance of approximately 45mH, and a no-load Q value ≥80. The coils are embedded in concealed grooves within the non-metallic frame of the enclosure, with a groove depth of 5mm. The surface is covered with a decorative cover plate of the same material as the enclosure, which is fixed by ultrasonic welding, with no visible fasteners.

[0044] 1.2 Implementation of the Dual-Use Code Verification Module

[0045] like Figure 5The flowchart of the algorithm transformation of the dual-code verification module shown illustrates the parallel paths of the first verification mode (SM3 hash) and the second verification mode (chaotic mapping).

[0046] The dual-code verification module is integrated into the main control circuit board inside the enclosure. Its core is a security chip (model: SCS2332, national cryptographic level 2 certification). The security chip has a pre-installed 128-bit unique identification code ID, which is stored in the Efuse fuse array and cannot be read after leaving the factory.

[0047] First verification mode (device legitimacy authentication): The identifier ID is hashed using the SM3 algorithm to generate a 256-bit device fingerprint H(ID), which is stored in the read-only memory area of ​​the security chip. External devices read the device fingerprint through the ISO7816 interface and compare it with a remote database to complete device legitimacy authentication.

[0048] The second verification mode (anti-electricity theft situational awareness key): The identification code ID is transformed using a chaotic mapping to generate the verification key K(t). The specific algorithm implementation is as follows:

[0049] Chaotic mapping parameter definition:

[0050] Instantaneous sampling value of power grid frequency f(t): The crystal oscillator clock (24MHz) of the metering unit sampling chip is divided by 1024 and then phase-locked for measurement by hardware frequency counter. The measurement resolution is 0.001Hz and the sampling period is 100ms.

[0051] The chaotic mapping transformation uses the instantaneous sampled value of the power grid frequency as the initial condition to perform a single forward nonlinear transformation on the identifier code, generating a time-varying key bound to the current power grid state. Because the power grid frequency is constrained by the overall power generation load balance, it is unpredictable and cannot be replicated, meaning the verification key cannot be calculated independently of the actual power grid environment.

[0052] The computational processing of unidirectional chaotic mappings employs an improved Logistic mapping, specifically:

[0053] Let the instantaneous sampling value of the power grid frequency be f (unit: Hz), and the initial conditions be... ;

[0054] Chaotic mapping equation: An improved form of the one-dimensional Logistic mapping is adopted. Where n is the number of iterations, Iterated a total of 16 times;

[0055] The results of 16 iterations are quantized into 16-bit binary numbers and concatenated into a 256-bit chaotic sequence.

[0056] Key generation: The identifier code is expanded to 256 bits and then XORed with the chaotic sequence to obtain a 256-bit verification key.

[0057] The one-way chaotic mapping computation is a one-way forward computation without feedback. It does not include a feedback loop that adjusts the input parameters based on the output. The 16 iterations are the state evolution steps inside the chaotic mapping. The transformation process is irreversible, and the generated verification key is inseparably bound to the current real-time physical state of the power grid.

[0058] 1.3 Implementation of Passive External Monitoring Unit

[0059] The passive external monitoring unit is located in an isolated monitoring area with independent power supply outside the enclosure, and has no electrical connection with the internal electrical system of the enclosure. The isolated monitoring area is powered by an independent lithium battery pack (capacity 10Ah, battery life ≥3 years), and communication is established with the remote master station through a 4G / 5G module to establish an encrypted tunnel.

[0060] Figure 2 The signal processing flow of the passive external monitoring unit is shown. Signal reception of the passive electromagnetic induction coil group: The passive electromagnetic induction coil group receives the spatial electromagnetic radiation signal leaked from the internal electrical circuit of the enclosure. The reception process of the spatial electromagnetic radiation signal meets the following technical constraints: the coil load impedance is set to 10kΩ (precision metal film resistor, temperature drift ≤5ppm / ℃), ensuring the received power ≤-60dBm, avoiding detectable load disturbances to the internal circuitry; the coil resonant frequency is tuned to the third harmonic (150Hz) of the 50Hz power frequency through a parallel capacitor to avoid strong fundamental frequency radiation and extract nonlinear load characteristics. The tuning capacitor is a CBB21 type, and its capacitance is determined by calculation.

[0061] C = 1 / ((2π × 150)^2 × L) ≈ 25.0nF; where L is the coil with an inductance of 45mH.

[0062] Implementation of spectrum decomposition processing:

[0063] The windowed interpolation FFT algorithm is used, with the following parameters:

[0064] Sampling rate: 3200Hz (meets the Nyquist criterion, covering up to the 50th harmonic);

[0065] Number of sampling points: 4096 (corresponding to a sampling duration of 1.28 seconds);

[0066] Window function: Blackman window, window coefficient w(n) = 0.42 - 0.5cos(2πn / N) + 0.08cos(4πn / N), where N=4096;

[0067] Interpolation factor: 4 times, achieved through zero padding in the frequency domain, with a frequency resolution of 0.25Hz.

[0068] After interpolation, the following components are extracted from the FFT output:

[0069] Power frequency fundamental component (50Hz±0.25Hz): Amplitude phase ;

[0070] Harmonic group components (150Hz, 250Hz, 350Hz): ;

[0071] Transient pulse components: extracted by wavelet transform, using db4 wavelet, decomposed into 6 layers, and extracted the energy of detail coefficients d1-d3.

[0072] Distance calculation processing: Weighted Euclidean distance is used, and the weighting coefficients are determined by the electricity theft sensitivity index of harmonic components (the electricity theft sensitivity index is determined based on the statistical analysis of harmonic variation amplitudes in historical electricity theft cases):

[0073] D = √(Σ(w_i × (A_i measured - A_i baseline)²)).

[0074] Weighting coefficient settings:

[0075] Fundamental amplitude weight = 0.15 (fundamental frequency is greatly affected by load fluctuations and has low sensitivity);

[0076] 3rd harmonic weight = 0.35 (The third harmonic changes significantly when electricity is stolen by a nonlinear load).

[0077] 5th harmonic weight = 0.25;

[0078] 7th harmonic weight = 0.15;

[0079] The transient pulse energy weight w_t = 0.10.

[0080] Dynamic Threshold Generator: The historical electricity theft feature pattern database is a collection of electromagnetic feature mutation patterns corresponding to known electricity theft methods. This database is stored in the external monitoring domain's Flash memory (128MB capacity) and includes 500 sets of de-identified electromagnetic feature vectors from known electricity theft cases. Each feature vector set includes 12 parameters such as the fundamental amplitude change rate, the 3rd / 5th / 7th harmonic amplitude change rate, harmonic phase offset, and transient pulse energy.

[0081] The environmental stress mapping table data represents the mapping data of the influence coefficients of temperature, humidity, and vibration environmental factors on the normal electromagnetic fingerprint offset; the environmental stress mapping table data is determined through standard environmental chamber calibration experiments before delivery, and the calibration conditions are as follows:

[0082] Temperature range: -40℃ to +70℃, in 10℃ increments, constant temperature stabilization time ≥2 hours;

[0083] Humidity range: 10%RH to 95%RH, in 10%RH increments, constant humidity stabilization time ≥ 1 hour;

[0084] Vibration frequency range: 5Hz to 500Hz, logarithmic sweep frequency, acceleration amplitude 2g.

[0085] During the calibration process, the offset of each component of the electromagnetic fingerprint at each environmental stress point is recorded, and a multivariate regression coefficient matrix is ​​established.

[0086] Boundary fusion calculation processing involves weighting and superimposing the abrupt change amplitude in the historical electricity theft feature pattern database with the offset coefficient in the environmental stress mapping table data to generate a judgment boundary that adaptively drifts with environmental conditions.

[0087] In boundary fusion calculation processing, the anomaly detection boundary under the current environmental conditions is:

[0088] ;

[0089] .

[0090] in, (Environmental compensation coefficient) =2.0 (safety margin coefficient).

[0091] 1.4 Implementation of Physical Interlocking and Isolation Units

[0092] The one-time fusible isolation barrier uses an alloy fuse structure connected in series with the current sampling circuit of the metering unit. The fuse material is AgCuO (silver copper oxide), with a rated current of 5A and fusing characteristics of ≤100ms at twice the rated current and ≤10ms at ten times the rated current. The fuse is encapsulated in a ceramic tube, the surface of which is coated with arc-quenching sand.

[0093] The triggering condition is: the dynamic threshold detector outputs a "beyond threshold range" signal, which drives the thyristor (model: BT138-600E) after opto-isolation. After the thyristor is turned on, it injects the charge of the energy storage capacitor (470μF / 400V) into the alloy fuse to achieve rapid melting.

[0094] The one-time fuse-type isolation barrier and the logic channel blocker are driven by the same trigger signal. The trigger signal is generated by the boundary judgment result of the passive external monitoring unit after opto-isolation. The opto-isolation is used to block the trigger signal from entering the passive external monitoring unit in the reverse direction.

[0095] The logic channel closure uses a CPLD device (model: EPM570) to implement state machine control. Under normal conditions, the CPLD caches the second verification mode key K(t) in its internal SRAM and provides a key access interface to the main control MCU via the SPI bus. After the latch is triggered, the CPLD performs the following actions:

[0096] ① Clear the key data in the internal SRAM and perform an all-zero overwrite;

[0097] ②Disable the SPI bus interface, pull the chip select signal low and lock it;

[0098] ③ Activate the mechanical optical switch of the emergency optical transmission channel.

[0099] Figure 3 The structure of the physical interlocking isolation unit and the emergency optical transmission channel is shown, illustrating the spatial layout of the one-time fusible isolation barrier, logic channel sealer, pre-embedded structural fiber optic cables, and mechanical optical switch. The interlocking action sequence—boundary violation detection, fuse blowing, key clearing, optical switch closing, and key uploading—is executed continuously within milliseconds.

[0100] Emergency optical transmission channel: The pre-embedded structural fiber optic filaments are optical-grade glass fiber filaments synchronously embedded in the pultrusion molding process of the housing composite material. The core diameter is 50μm, the cladding diameter is 125μm, and the numerical aperture is 0.22. The fiber optic filaments are arranged in a sinusoidal, meandering pattern in the middle high-dielectric-constant coupling layer of the housing wall, with a peak spacing of 12mm (1.5 times the housing wall thickness of 8mm), forming a multiplexed structure for both mechanical stress buffering and optical transmission paths.

[0101] After the housing is formed, the two ends of the optical fiber are physically broken through a hot-melt sealing process: a hot air gun is used to heat the resin to the melting temperature (about 180°C), so that the unsaturated polyester resin around the end of the fiber melts and solidifies, forming an opaque light-isolating plug.

[0102] The pre-embedded optical fiber acquires the key data stream to be transferred and performs optical pulse modulation processing on it to obtain an optical key signal, which is then sent to the optical receiving and demodulation module in the external independent security domain. The optical receiving and demodulation module performs photoelectric conversion and demodulation processing on the optical key signal to obtain the restored key data, thus completing the emergency transfer and sealing of the key.

[0103] The mechanical optical switch is driven by a shape memory alloy wire (NiTi alloy, 0.5 mm in diameter, phase transition temperature Af = 70 °C) embedded in the housing wall. The shape memory alloy wire and the pre-embedded optical fiber are jointly embedded in the middle high dielectric constant coupling layer. Under normal conditions, the shape memory alloy wire is in the low-temperature martensitic phase and is in a bent state. The elastic stress of the spring keeps the optical fiber in a bent and broken state. When the latch-up is triggered, the driving current (1 A, lasting 200 ms) heats the alloy wire to the austenitic phase. The alloy wire contracts and straightens, restoring the optical fiber to a straight optical coupling state, forming a one-time optical transmission link.

[0104] The switching action of the mechanical optical switch is achieved through the electrothermal drive of the shape memory alloy wire embedded in the housing wall. After receiving the heating current of the trigger signal, the shape memory alloy wire undergoes a phase change and contracts. The mechanical tension overcomes the elastic stress and straightens the pre-embedded optical fiber. The mechanical tension only acts on the one-time deformation of the pre-embedded optical fiber and does not cause structural damage to the housing wall.

[0105] The optical pulse modulation processing employs on-off keying (OOK) modulation, with an 850nm VCSEL laser as the light source, a drive current of 10mA, an optical power of -3dBm, and a modulation rate of 1Mbps. The optical receiver demodulation module uses a PIN photodiode (model: PIN-10D) with a responsivity of 0.5A / W, which is then converted back into a digital signal by a transimpedance amplifier (gain 100kΩ) and a comparator.

[0106] 1.5 Implementation of Active Reverse Verification Unit

[0107] The challenge generator receives the second verification mode key K(t) (128 bits) and the instantaneous phase sample value θ(t) of the current grid frequency (16 bits, resolution 0.01°).

[0108] The time-varying sequence generation process uses the AES-128 encryption algorithm, with K(t) as the key and θ(t) concatenated with a timestamp T (32-bit Unix time, in seconds) as the plaintext, to generate a 128-bit challenge code C: C = AES-128_Encrypt(K(t), θ(t) || T).

[0109] The timeliness of a single challenge code is guaranteed by a timestamp T; the challenge code is only valid for 5 seconds after it is generated.

[0110] The challenge generator generates a time stamp while generating the verification challenge code. This time stamp is a Unix timestamp (in seconds) at the moment the challenge code is generated. The verification challenge code and the time stamp are bound and encapsulated before being sent to the heterogeneous dual-channel transmitter. When the cross-pass receiver receives the response signal, it synchronously extracts the time stamp echo field from the response and compares the time stamp echo field with the original time stamp recorded by the challenge generator. If the two are inconsistent or the time difference exceeds 5 seconds, the "time expired" sub-result is directly output, triggering an electricity theft alarm.

[0111] Heterogeneous dual-channel transmitter:

[0112] Power line carrier channel: OFDM modulation is used, with a carrier frequency of 3-500kHz, a subcarrier spacing of 1.5625kHz, a QPSK modulation scheme, and a transmit power of 1W. The challenge code is mapped to the OFDM subcarrier after being Reed-Solomon encoded (RS(255,239)) and convolutionally encoded (code rate 1 / 2, constraint length 7).

[0113] Wireless radio frequency channel: Utilizing the Sub-GHz band (470MHz), FSK modulation, frequency offset ±50kHz, transmit power 17dBm, and data rate 9.6kbps. The challenge code is transmitted after being encoded using the same channel.

[0114] The dual heterogeneous challenge signals propagate through different physical media, making it difficult for electricity thieves to intercept both signals simultaneously and launch a coordinated attack.

[0115] Cross-backhaul receiver: The power supply must send a response through a cross-backhaul channel different from the receive channel. If the power supply receives the challenge through a power line carrier channel, it must send the response back through a radio frequency channel; and vice versa. The response code R is the first 128 bits of a 256-bit digest of the challenge code C hashed by SM3: R = Truncate(SM3(C), 128).

[0116] The response validity determination process compares the returned response R with the locally calculated expected value R'. If R = R', it is determined to be a valid response.

[0117] The timeliness consistency comparison compares the response code field in the response signal with the expected response code calculated locally by the challenge generator bit by bit. If they are completely consistent, the "code consistent" sub-result is output; otherwise, the "code inconsistent" sub-result is output. The response timing compliance judgment process checks whether the reception time of the response signal is within the effective period of the receive enable signal of the time window controller. If so, the "timing compliance" sub-result is output; otherwise, the "timing violation" sub-result is output. Only when the response judgment result contains both "code consistent" and "timing compliance" is it judged as a valid response; otherwise, an electricity theft alarm is triggered.

[0118] Time window controller: The response time limit is set to 300ms. The basis for determining this time limit is:

[0119] Propagation delay of power line carrier signal (typical 100m line): ≤1ms;

[0120] Wireless radio frequency signal propagation delay (typical 300m line-of-sight): ≤1ms;

[0121] Normal processing delay at the power end (microcontroller): ≤50ms;

[0122] Safety margin: 248ms.

[0123] The signal transfer and retransmission delay (including signal reception, storage, analysis, and forwarding) of conventional electricity theft devices is usually ≥500ms. Therefore, the 300ms time limit effectively suppresses forwarding-type electricity theft.

[0124] like Figure 4 The challenge-response timing diagram of the active reverse verification unit shown illustrates the timing relationship between challenge generation, dual-channel transmission, time window, and cross-transmission.

[0125] Figure 4 In the middle, the participants (at the top, with lifelines from top to bottom): Challenge Generator—generates and sends challenge code C, Heterogeneous Dual-Channel Transmitter—parallel modulates power line carrier + radio frequency, Power User—receives and processes challenge code, transmits response R, Cross-Return Receiver—receives response and determines validity, Time Window Controller—starts 300ms countdown and outputs enable signal.

[0126] Timing messages (arranged on timeline): 0ms: ① Challenge generator → Heterogeneous dual-channel transmitter (sends challenge code C); 0-10ms: ② Heterogeneous dual-channel transmitter → Power user (power line carrier + radio frequency dual-channel parallel); 10-60ms: Power user receives and processes the challenge code; 60-70ms: ③ Power user → Cross-backhaul receiver (backhaul response R, cross-channel); 0-300ms: Time window controller starts countdown and outputs enable signal to cross-backhaul receiver; 70ms: Cross-backhaul receiver receives response and performs response validity judgment: YES → verification passed, NO → electricity theft alarm; 300ms: Timeout → electricity theft alarm.

[0127] 1.6 Implementation of Simulated Sensor Node Array

[0128] Simulated sensor nodes: Eight simulated sensor nodes are arranged in the non-functional area on the surface of the enclosure. They are 15mm in diameter metallic discs with the word "SENSOR" engraved on the surface, and their appearance is consistent with that of the real monitoring nodes (lead-out terminals of the passive electromagnetic induction coil group).

[0129] The simulated sensor node has a solid structure filled with resin and contains no electronic components. The node is fixed to the surface of the housing with M3 stainless steel screws, with the screws driven to the same depth (8mm) as the real node.

[0130] The leads of the simulated sensor nodes and the passive electromagnetic induction coil group are arranged using an interleaved layout algorithm, making it impossible for electricity thieves to distinguish between genuine and fake nodes by visual positional patterns or simple electromagnetic detection. The interleaved layout algorithm uses a linear congruent generator to generate a pseudo-random sequence (parameters: modulus m=2^16, multiplier a=25173, increment c=13849), with the seed being the lower 16 bits of the unique identification code of the dual-use verification module. Each item of the pseudo-random sequence is moduloed by the total number of positions that can be arranged on the surface of the box to obtain the position index of the simulated node, and the remaining positions are automatically assigned to the positions of real monitoring nodes or empty spaces.

[0131] Implementation of the staggered layout algorithm:

[0132] The surface of the box is divided into a 4×4 grid array (16 positions in total), and the nodes are arranged according to the following pseudo-random sequence:

[0133] Actual node locations: 3rd, 6th, 10th, and 13th cells (determined based on a pseudo-random sequence generated by LCG using the device serial number);

[0134] Simulation node positions: grids 1, 2, 4, 5, 7, 8, 9, and 11;

[0135] Empty spaces: 12th, 14th, 15th, and 16th spaces;

[0136] This layout results in a random and unpredictable distribution of real and simulated nodes.

[0137] 1.7 Implementation of the One-Way Heartbeat Verification Mechanism

[0138] The unidirectional optical isolation channel is an independent conventional communication channel, physically isolated and functionally separate from the emergency optical transmission channel. The unidirectional optical isolation channel is used for periodic heartbeat transmission (normal operation), while the emergency optical transmission channel is used for emergency key transfer (activated only once when physically locked). The plastic optical fiber of the unidirectional optical isolation channel and the pre-embedded structural optical fiber of the emergency optical transmission channel are spatially separated within the enclosure wall, with a minimum spacing of ≥20mm to avoid optical crosstalk.

[0139] The unidirectional optical isolation channel is implemented using a fiber optic coupler, comprising a light-emitting end, a light-receiving end, and a transmission medium. The light-emitting end is located inside the metering unit of the enclosure and is an infrared LED (wavelength 940nm, drive current 20mA), which converts the electrical signal of the heartbeat frame into an optical signal. The light-receiving end is located in an external independent monitoring domain and is a phototransistor (model PT334-6B, dark current ≤100nA), which converts the optical signal into an electrical signal. The transmission medium is a plastic optical fiber (core diameter 1mm, length 50cm), which passes through a pre-drilled hole in the enclosure wall, and the gap between the hole and the optical fiber is sealed with epoxy resin. There is no electrical connection between the light-emitting end and the light-receiving end, and the light-receiving end has no reverse drive circuit, so it is physically impossible to convert the electrical signal into an optical signal and send it into the enclosure, thus enabling unidirectional transmission of the signal only from the inside to the outside.

[0140] The heartbeat frame generator is located inside the metering unit of the enclosure and generates a heartbeat frame every 10 seconds. The heartbeat frame generator includes a safety MCU (model: SCS2332) and a true random number generator (based on a ring oscillator entropy source); the status parameter set includes the RMS value of voltage, RMS value of current, active power, power factor and internal temperature.

[0141] The heartbeat frame contains:

[0142] Frame header: 0xEB90 (2 bytes);

[0143] Frame length: 32 bytes;

[0144] Metering status word: 8 bytes, including compressed representations of RMS voltage, RMS current, active power, and power factor;

[0145] Internal temperature: 2 bytes, resolution 0.1℃;

[0146] Internal clock: 4 bytes, Unix timestamp (seconds);

[0147] Random number padding: 8 bytes, generated by a true random number generator;

[0148] Message authentication code: 4 bytes, generated by the SM3-HMAC algorithm, and the key is the device fingerprint of the first verification mode of the dual-use verification module.

[0149] The message authentication code is used to verify the integrity and authenticity of the heartbeat frame, preventing the forgery of heartbeat frames after the internal MCU is replaced;

[0150] The compressed fingerprint generation process uses the MinHash algorithm to extract eight 16-bit sub-features from the meter status word. After random permutation, the minimum value is taken to form a 64-bit compressed fingerprint. The seed of the random permutation function is the device serial number, ensuring that compressed fingerprints from different devices are not comparable.

[0151] The consistency comparator includes a time alignment buffer; the time alignment buffer pairs data whose acquisition timestamp of external electromagnetic features differs from the generation timestamp of internal electromagnetic features by ±1 second into a synchronous comparison group.

[0152] Consistency deviation calculation includes the fundamental amplitude deviation rate δA, the third harmonic amplitude deviation rate δA3, and the power factor deviation. The calculation; when δA ≥ 5% and lasts for 3 heartbeat cycles, or And last for two heartbeat cycles, or If the alarm continues for three consecutive heartbeat cycles, it is determined that "external characteristics are normal but internal state is abnormal", triggering an electricity theft alarm. "External characteristics are normal but internal state is abnormal" corresponds to an attack scenario in which the electricity thief maintains normal external monitoring through external electromagnetic shielding or injection, but the internal metering has been tampered with.

[0153] 1.8 System Integration of Layered Independent Defense Architecture

[0154] The anti-theft verification of non-metallic energy metering boxes adopts a layered independent defense architecture, which includes a contact-based physical defense layer and a non-contact electromagnetic defense layer. The logical relationship of the layered independent defense architecture is as follows: Figure 6 As shown.

[0155] The contact-type physical defense layer consists of physical locking and isolation units, used to irreversibly disconnect the physical path between the metering unit and the external electrical interface against physical electricity theft attempts that directly contact the enclosure. The contact-type physical defense layer is triggered solely by the out-of-range judgment result of the passive external monitoring unit. The specific triggering path is as follows: the dynamic threshold determiner outputs a "beyond threshold range" signal → through opto-isolation → drives the BT138-600E thyristor to conduct → the energy storage capacitor discharges to the alloy fuse → the fuse blows. This triggering path is a unidirectional hardwired connection, does not pass through the enclosure's main control MCU, does not rely on any software logic, and is not confirmed by the verification result of the active reverse verification unit.

[0156] The non-contact electromagnetic defense layer consists of a passive external monitoring unit and an active reverse verification unit working together to perform passive electromagnetic monitoring and active reverse verification against electromagnetic electricity theft in the area surrounding the enclosure. The non-contact electromagnetic defense layer operates in three modes: continuous passive monitoring, high-frequency monitoring (triggered by surrounding electromagnetic activity detectors), and active reverse verification (activated after being triggered by physical interlocking). Any change in the non-contact electromagnetic defense layer's state—including monitoring mode switching, verification result determination, and alarm information generation—does not affect the trigger response timing of the contact physical defense layer.

[0157] There is no control coupling between the contact-based physical defense layer and the non-contact electromagnetic defense layer, specifically manifested as follows:

[0158] No shared electrical circuit: The physically locked fuse drive circuit is electrically completely isolated from the electromagnetic monitoring coil receiving circuit;

[0159] No shared communication bus: The trigger signal for physical latching is not transmitted via RS485, SPI or any communication bus, but is directly driven by independent hardwiring;

[0160] No shared trigger signal source: The trigger source for physical blocking is only passive monitoring of boundary crossing judgment. The decoy detection, heartbeat verification, and active reverse verification of the electromagnetic defense layer do not trigger physical blocking.

[0161] Each is powered independently: the fuse drive power supply (energy storage capacitor 470μF / 400V) of the contact physical defense layer and the monitoring unit power supply (independent lithium battery pack 10Ah) of the non-contact electromagnetic defense layer are physically separated.

[0162] When the non-contact electromagnetic defense layer fails due to communication interference, power failure, or malicious attack, the contact physical defense layer can still independently complete the triggering based on the boundary judgment of passive monitoring, ensuring that the physical isolation of the metering unit is not bypassed. Conversely, when the contact physical defense layer is triggered, the non-contact electromagnetic defense layer can continue to perform active reverse verification and evidence solidification, forming a defense-in-depth posture of "physical blockade as the bottom line and electromagnetic monitoring as the front line".

[0163] Example 2: Method Example

[0164] The complete process of the anti-electricity theft verification method of the present invention is based on the system implementation of Embodiment 1.

[0165] 2.1 System Initialization Phase

[0166] Step S101: After the device is powered on, the dual-code verification module reads the unique identification code ID from the security chip and performs device legitimacy authentication in the first verification mode. The main control MCU sends an authentication command to the security chip through the ISO7816 interface. The security chip returns the SM3 hash value H(ID). The main control MCU compares this hash value with the remote master station database. If the comparison matches, the device enters normal operation.

[0167] Step S102: The passive external monitoring unit activates the passive electromagnetic induction coil group to establish a multi-dimensional fingerprint database for normal operation. During the initial 48 hours, the system is in learning mode, collecting spectral feature vectors every 10 minutes. After statistical analysis, a baseline vector μ and a standard deviation vector σ are established. Once the baseline is established, the system switches to monitoring mode.

[0168] Step S103: The dynamic threshold generator loads historical electricity theft feature pattern library data and environmental stress mapping table data, and initializes the weighting coefficients for boundary fusion calculation processing.

[0169] 2.2 Passive Monitoring Phase

[0170] Step S201: The passive electromagnetic induction coil group receives the spatial electromagnetic radiation signal leaked from the internal electrical circuit of the enclosure at a period of 10 minutes. The coil load impedance is maintained at 10kΩ, and the received power is ≤-60dBm.

[0171] Step S202: Perform spectral decomposition processing on the space electromagnetic radiation signal. Specifically, after the 4096 sampled data points are weighted by the Blackman window, a 4x interpolation FFT is performed to extract the fundamental frequency component (50Hz±0.25Hz), harmonic group components (150Hz, 250Hz, 350Hz), and transient pulse components.

[0172] Step S203: The silent comparison engine performs mode distance calculation processing on the power frequency fundamental component, harmonic group component and transient pulse component to obtain the real-time mode distance value D.

[0173] Step S204: The dynamic threshold generator receives the current temperature, humidity, and vibration sampling values, performs environmental stress vector construction processing, and obtains a three-dimensional environmental stress vector.

[0174] Step S205: The dynamic threshold generator performs boundary fusion calculation on the historical electricity theft feature pattern library data and the environmental stress mapping table data to obtain the anomaly judgment boundary [θ_L, θ_H] under the current environmental conditions.

[0175] Step S206: The dynamic threshold determiner performs threshold range out-of-bounds judgment processing on the real-time mode distance value D and the anomaly judgment boundary [θ_L, θ_H]. If D > θ_H or D < θ_L, the out-of-bounds judgment result of "exceeding the threshold range" is output, and the process proceeds to step S301; otherwise, the process returns to step S201.

[0176] 2.3 Physical Lockout Phase

[0177] Step S301: The physical interlocking isolation unit receives the boundary judgment result and triggers a one-time fuse-type isolation barrier. The thyristor BT138-600E turns on, the energy storage capacitor discharges to the alloy fuse, and the fuse melts within ≤100ms, cutting off the current sampling circuit between the metering unit and the external electrical interface.

[0178] Step S302: The logic channel closure performs key clearing and channel closure: clears the second verification mode key K(t) in the security chip SRAM, closes the SPI bus interface, and activates the emergency optical transmission channel.

[0179] Step S303: The shape memory alloy wire in the mechanical optical switch is heated by electricity, shrinks and straightens, so that the pre-embedded optical fiber wire is restored to a straight state, forming a one-time optical transmission link.

[0180] Step S304: The logic channel closure sends the key data stream to be transferred (K(t) backup after SM4 encryption) into the optical pulse modulator to obtain the optical key signal, which is then transmitted to the external independent security domain via optical fiber.

[0181] Step S305: The optical receiving and demodulation module of the external security domain performs photoelectric conversion and demodulation processing to obtain the restored key data and complete the sealing.

[0182] 2.4 Active Reverse Verification Phase

[0183] Step S401: The active reverse verification unit is started, and the challenge generator reads the current second verification mode key K(t) (if it has been cleared, it is read from the archived backup of the external security domain) and the instantaneous phase sample value θ(t) of the power grid frequency.

[0184] Step S402: The challenge generator performs time-varying sequence generation processing: C = AES-128_Encrypt(K(t), θ(t) || T), to obtain the single time-sensitive verification challenge code C.

[0185] Step S403: The heterogeneous dual-channel transmitter receives the challenge code C, performs parallel processing of power line carrier modulation and radio frequency modulation, and obtains dual heterogeneous challenge signals, which are sent to the power user through the power line carrier channel and the radio frequency channel respectively.

[0186] Step S404: The time window controller starts a 300ms countdown. The cross-backhaul receiver listens to the cross-backhaul channel during the countdown.

[0187] Step S405: If the power user sends a valid response R through the cross-passback channel within 300ms, then the response validity determination process is executed. If the valid response R matches the expected value, it is determined to be a legitimate power user, and the process proceeds to step S406; otherwise, the process proceeds to step S407.

[0188] Step S406: The system maintains the locked state, but sends a message to the remote master station that "verification passed but physical lock requires manual reset".

[0189] Step S407: Trigger an electricity theft alarm and upload the alarm information, challenge code C, valid response R (if any), and timestamp to the remote master station via the 4G module.

[0190] 2.5 Heartbeat Verification Phase

[0191] Step S501: The heartbeat frame generator receives the set of internal operating status parameters every 10 seconds, performs compressed fingerprint generation processing, and obtains an unforgeable heartbeat frame.

[0192] Step S502: The heartbeat frame is sent to the external monitoring domain through a one-way optical isolation channel.

[0193] Step S503: The table-in-table consistency comparator receives the external electromagnetic features and compressed fingerprints in the heartbeat frame collected by the passive external monitoring unit, and performs consistency deviation calculation processing.

[0194] Step S504: If the deviation rate is ≥5% and continues for 3 cycles, then trigger an electricity theft alarm.

[0195] Example 3: Enhanced decoy detection scheme

[0196] To further enhance the early warning capability for electromagnetic electricity theft, the passive external monitoring unit can also work in conjunction with a fake metering pulse transmitter and surrounding electromagnetic activity detectors.

[0197] The pseudo-metering pulse transmitter emits low-power pseudo-metering pulse signals into the external space of the enclosure at random intervals. The random intervals are generated by a linear congruent generator (LCG) with parameters: a=1664525, c=1013904223, m=2^32, and the seed is the device serial number. The interval ranges from 30 seconds to 300 seconds.

[0198] The pseudo-metering pulse signal simulates the real metering data stream in terms of spectral characteristics, but the encoding has a hidden identity watermark: the fundamental frequency is 50Hz, the amplitude varies according to the typical residential load curve (0.5A to 20A), and the third harmonic is superimposed (the amplitude is 5% of the fundamental frequency). The signal encoding adopts the DL / T645-2007 protocol frame format, but the data field is filled with pseudo-random numbers.

[0199] The identity watermark uses an asymmetric embedding mechanism, embedding it into the harmonic components of the pseudo-metering pulse signal through spread spectrum modulation. The spread spectrum modulation uses a pseudo-random code to directly spread the watermark bits using a direct sequence, with a spreading gain of 20dB. The embedding method is as follows: A 16-bit watermark sequence W is inserted before the checksum of the DL / T645 frame. W is the first 16 bits of the device serial number hashed using SM3, and is XORed with the frame sequence number: W' = W ⊕ FrameSeq.

[0200] The peripheral electromagnetic activity detectors are deployed within a 5m radius around the enclosure and are set up in conjunction with the pseudo-metering pulse transmitter to monitor only electromagnetic activity signals containing identity watermarks.

[0201] The peripheral electromagnetic activity detector uses a loop antenna (20cm in diameter, 10 turns) to receive electromagnetic activity signals from the external space of the receiving box. After the received signal is bandpass filtered (45-55Hz), amplified (60dB gain), and converted by A / D (16-bit, 10kHz sampling rate), it is processed for identity watermark extraction and abnormal pattern recognition to obtain the abnormal electromagnetic activity judgment result.

[0202] The identity watermark extraction process utilizes the same pseudo-random code and synchronization sequence as the pseudo-metering pulse transmitter to extract the watermark sequence from the electromagnetic activity signal through correlation despreading. If the extracted watermark sequence matches the identity watermark currently emitted by the pseudo-metering pulse transmitter, a "watermark match" sub-result is output; otherwise, a "watermark mismatch" sub-result is output. The abnormal pattern recognition process is only performed on the electromagnetic activity signal corresponding to the "watermark match" sub-result. This includes detecting whether the electromagnetic activity signal has an amplitude amplification factor ≥1.5 relative to the original signal emitted by the pseudo-metering pulse transmitter, or harmonic tampering with the third harmonic amplitude deviating from ±20%, or signal forwarding with a transmission delay ≥10ms. If any of the above abnormalities exist, a "abnormal activity exists" sub-result is output.

[0203] When the abnormal electromagnetic activity determination result includes both "watermark matching" and "abnormal activity exists", the surrounding electromagnetic activity detector does not directly trigger the physical blocking isolation unit, but instead sends a sampling frequency increase command to the passive external monitoring unit. After receiving the sampling frequency increase command, the passive external monitoring unit increases the sampling rate from the first sampling rate (3200Hz) to the second sampling rate (12800Hz) and the number of sampling points from the first number of sampling points (4096 points) to the second number of sampling points (16384 points), entering the high-frequency monitoring mode. The high-frequency monitoring mode continues for a preset monitoring period (e.g., 10 minutes). If the operating characteristics are detected to deviate from the preset baseline threshold within the preset monitoring period, the physical blocking isolation unit is triggered. If no deviation is detected, it automatically returns to the first sampling rate and the first number of sampling points, and sends a monitoring recovery confirmation signal to the surrounding electromagnetic activity detector.

[0204] The identity watermark uses an asymmetric embedding mechanism:

[0205] Embedding end (pseudo-metering pulse transmitter): The watermark sequence W is embedded into the harmonic components of the pseudo-metering pulse signal through spread spectrum modulation. The spread spectrum modulation uses a pseudo-random code (PN code) to directly spread the watermark bits in sequence. The spread spectrum gain is 20dB, so that the power of the watermark signal is 20dB lower than the main lobe power of the pseudo signal, thus achieving covert embedding.

[0206] Extraction end (peripheral electromagnetic activity detector): Stores the same PN code and synchronization sequence as the pseudo metering pulse transmitter. Extracts the watermark sequence from the received signal through correlation despreading. Correlation despreading utilizes the autocorrelation characteristics of the PN code to recover the spread-spectrum watermark signal from the noise substrate. The recovery gain is matched with the spread-spectrum gain.

[0207] Watermark extraction process: Perform frame parsing synchronized with the transmitter on the received signal, extract the suspected watermark sequence W'', and calculate the Hamming distance d between it and the expected watermark W'. If d ≤ 2 (allowing 2 bits of error), it is determined that "there is a forwarding activity targeting the fake signal"; if there is fundamental amplitude amplification (amplification factor ≥ 1.5) or harmonic component tampering in the received signal (3rd harmonic amplitude deviation ±20%), it is determined that "there is amplification or tampering activity targeting the fake signal".

[0208] When the abnormal electromagnetic activity determination result indicates the presence of the aforementioned activity, a sampling frequency increase command is sent to the passive external monitoring unit, increasing the sampling rate from 3200Hz to 12800Hz and the number of sampling points from 4096 to 16384, in order to improve the accuracy of subsequent monitoring.

[0209] Example 4: Virtual Metering Point Trapping Scheme

[0210] To further increase the difficulty for electricity thieves to detect, non-metallic energy metering boxes may also include a virtual metering loop generator and a verification request routing discriminator.

[0211] The virtual metering loop generator is used to construct at least one virtual metering loop that is not physically connected to the power grid inside a non-metallic enclosure. The virtual metering loop has electromagnetic scattering characteristics similar to a real metering loop, but it does not perform energy metering functions; its sole function is to act as a decoy node for illegal probing. The real metering loop is the current and voltage sampling loop of the metering unit.

[0212] The virtual metering loop includes:

[0213] Air-core inductor coil: The frame material is the same as that of the real current transformer frame (PBT+GF30), with an outer diameter of 30mm, an inner diameter of 20mm, a height of 25mm, and 200 turns of 0.2mm enameled wire wound on it. The inductance is about 8mH. The air-core inductor coil is wound on the insulated frame reserved inside the non-metallic enclosure. This insulated frame is made of the same material and mold as the current transformer frame of the real metering circuit, so that the electromagnetic scattering characteristics of the virtual metering circuit are consistent with the spatial radiation of the real metering circuit.

[0214] No-load capacitor array: 4 CBB capacitors are connected in parallel (1μF / 630V×4), and are weakly connected to the internal ground potential of the enclosure through a high-resistance bleeder resistor (10MΩ metal film resistor). This weak connection is only used to maintain the electrostatic reference potential of the capacitor array and does not constitute a power transmission path.

[0215] The virtual metering circuit receives the alternating magnetic field energy leaked from the real metering circuit through electromagnetic induction coupling: the magnetic field generated by the primary current of the real current transformer passes through the air-core inductor of the virtual metering circuit, inducing an electromotive force e = -N dΦ / dt. After passing through a high-impedance attenuation network (divided by two 10MΩ resistors), a simulated signal is formed that is proportional to the amplitude of the real metering signal but has a randomly drifting phase. The signal amplitude is about 0.1% of the real signal, and the phase has a random drift due to the high-impedance network (drift range ±15°).

[0216] The virtual metering loop is configured with a differentiated identification code. This differentiated identification code and the identification code of the real metering loop are both 8-byte address codes, using different encoding prefixes. The high byte of the differentiated identification code is 0x55, while the high byte of the identification code of the real metering loop is 0xAA. The differentiated identification code is not publicly disclosed and is only stored in the read-only area of ​​the local security chip in the enclosure (neither legitimate power users nor remote master stations know this identification code, and any external verification request pointing to the differentiated identification code is considered an illegal probe).

[0217] The verification request routing discriminator is used to receive external verification requests (compliant with DL / T645-2007 or DL / T698.45 protocol frame format) through the external communication interface of the enclosure. The communication interface includes at least one of RS485 bus interface, power line carrier communication interface or low-power wireless communication interface. The verification request routing discriminator performs target address parsing processing on the external verification request to obtain the request target identifier.

[0218] The target address resolution process parses the address field of the external verification request according to the DL / T645-2007 or DL / T698.45 protocol frame format, extracts the high byte field of the address field, and compares this high byte field with 0xAA and 0x55 byte by byte. When the high byte field of the target identifier is equal to 0x55, it is determined that the external verification request points to the virtual metering loop. The verification request route discriminator outputs a high-level trigger signal to the physical interlocking isolation unit through an independent hardwire (the independent hardwire does not pass through the main control MCU of the enclosure to avoid blocking the trigger path after the main control MCU is tampered with), directly triggering the physical interlocking isolation unit (the physical interlocking isolation unit executes the interlocking action after receiving the high-level trigger signal, and the interlocking action has the same response priority as the interlocking action triggered by the passive external monitoring unit). When the high byte field of the target identifier is neither equal to 0xAA nor equal to 0x55, it is also determined to be an illegal address, and a high-level trigger signal is output to the physical interlocking isolation unit through an independent hardwire, directly triggering the physical interlocking isolation unit.

[0219] Example 5: Layered and Progressive Chain of Evidence Scheme

[0220] To solidify judicial evidence of electricity theft and facilitate subsequent legal prosecution, non-metallic electricity metering boxes can also be configured with a layered, progressive evidence chain construction module. This module includes a time-series evidence recorder, a false instruction decoy releaser, and a response capture recorder.

[0221] The time-series evidence recorder operates in parallel with the passive external monitoring unit, continuously receiving abnormal electromagnetic feature sequences collected by the passive external monitoring unit and temporarily storing the feature data of the most recent N sampling periods in a circular buffer. When the physical locking isolation unit is triggered, the time-series evidence recorder receives a trigger freeze signal, timestamps and compresses the data in the current circular buffer along with historical data from M sampling periods prior to the trigger time, and archives them to obtain a judicial-grade time-series evidence package. Among them, N≥20 (covering an abnormal evolution process of about 25 minutes) and M≥10 (covering the historical baseline before the trigger of about 12 minutes).

[0222] Specifically, the abnormal electromagnetic feature sequence includes spectral feature vectors for 10 consecutive sampling periods (1.28 seconds per period), each vector being 12-dimensional (fundamental amplitude / phase, 3rd / 5th / 7th harmonic amplitude / phase, transient pulse energy).

[0223] The timestamp is generated using a GPS / BeiDou dual-mode timing module (model: ATGM336H), with a timing accuracy of ≤100ns and a timestamp format conforming to the IEEE 1588 standard. The compressed archiving process uses the LZ4 lossless compression algorithm, with a compression ratio of approximately 3:1. The archive file header includes the device serial number, the start time of the anomaly, and the anomaly type identifier.

[0224] The decoy release device is time-linked with the physical interlocking isolation unit. After the physical interlocking isolation unit is triggered, it releases the device after a preset time interval (e.g., 5 seconds). The decoy release device sends a fake metering reset command to the outside via the RS485 interface. The fake metering reset command uses the same frame format and verification algorithm as the real metering reset command. The command format conforms to the DL / T645-2007 protocol, and the control code is 0x1D (disguised as a reset command). However, the data field contains an address out-of-bounds value (e.g., 0xFFFFFFFF). Address out-of-bounds values ​​will be blocked by address validity checks in legitimate systems, but may be directly executed in unauthorized control devices. If there is an unauthorized control device at the power consumption end, the device may respond to this fake command and perform an incorrect operation, thus exposing its existence.

[0225] The false metering reset command is sent through the remaining communication line downstream of the blown isolation barrier. The remaining communication line is an RS485 bus or power line carrier coupling capacitor that still maintains a physical connection after the isolation barrier blows. The remaining communication line does not carry electrical energy and only retains signal transmission capability.

[0226] The response capture recorder and the false command decoy releaser are set to be synchronized. At the same time as the false command decoy releaser sends a false command, the response listening window is started (lasting for 10 seconds). During the response listening window, the response capture recorder continuously listens for the response signal from the power user through the remaining communication line. If a response signal is received within the response listening window, the complete communication process is recorded to obtain a judicial evidence data packet.

[0227] The RS485 bus is continuously monitored, and all response frames are recorded. The complete communication process recording includes recording the request frame content (false command text), response frame content, transmission timestamp, response timestamp, signal strength (RS485 bus differential voltage amplitude or carrier signal power spectral density), and channel bit error rate; if no response signal is received within the response monitoring window, a zero response record is generated (including transmission time, monitoring duration, and channel noise floor).

[0228] The judicial-grade time-series evidence package and judicial evidence collection data package are uploaded to the external security domain in real time through the emergency optical transmission channel. After the upload is completed, the local cache is securely erased (all zeros are overwritten 3 times). The trigger timestamp in the judicial-grade time-series evidence package and the sending timestamp in the response capture recorder have a deviation of ≤1ms, which together constitute a hierarchical and progressive judicial evidence chain.

[0229] Example 6: Power Disturbance Induced Scheme

[0230] To further induce electricity thieves to reveal their attack intentions, the passive external monitoring unit can also be configured with a power consumption disturbance controller.

[0231] The power disturbance controller receives a slight abnormality indication signal from the passive external monitoring unit, performs non-core power reduction processing on the slight abnormality indication signal, and obtains a power reduction operation mode. The power reduction operation mode changes the electromagnetic radiation characteristics of the enclosure to simulate the illusion of insufficient power supply to the equipment.

[0232] The minor anomaly indication signal indicates that the deviation of the operating state characteristics has not reached the physical interlocking trigger threshold. The conditions for its generation are: the real-time mode distance value D is within 50%-80% of the threshold range (i.e., close to an anomaly but not exceeding the limit).

[0233] Specific actions to reduce power consumption for non-core functions: Turn off LED indicators: cut off the power supply to the indicator light driver circuit (PMOS shutdown), reducing the current from 20mA to 0mA; Reduce buzzer drive current: reduce the buzzer PWM duty cycle from 50% to 10%, and the sound pressure level from 85dB to 65dB; Extend the communication module sleep cycle: extend the wake-up interval of the 4G module from 30 seconds to 300 seconds, and reduce the average power consumption from 2W to 0.5W.

[0234] The aforementioned power reduction actions are controlled by independent GPIO, bypassing the feedback adjustment loop of the main control MCU, thus avoiding any impact on the metering core unit.

[0235] Example 7: Environmental Stress Decoupling Enhancement Scheme

[0236] To further improve the accuracy of anomaly detection and reduce the false alarm rate caused by environmental factors, the dynamic threshold generator may also include an environmental stress decoupling processor.

[0237] The environmental stress decoupling processor receives real-time temperature, humidity, and vibration acceleration samples, and performs environmental stress vector construction on these three types of data to obtain a three-dimensional environmental stress vector. The dynamic threshold generator receives the three-dimensional environmental stress vector and performs environmental-fingerprint offset mapping on it to obtain an environmentally compensated fingerprint baseline, which is then sent to the silent comparison engine.

[0238] The environmental fingerprint offset mapping process uses a multivariate regression coefficient matrix from the environmental stress mapping table data to convert the three-dimensional environmental stress vector into the expected offset of each component of the electromagnetic fingerprint. The multivariate regression coefficient matrix is ​​determined through standard environmental chamber calibration experiments before leaving the factory, with a calibration temperature range of -40℃ to +70℃, a humidity range of 10%RH to 95%RH, and a vibration frequency range of 5Hz to 500Hz.

[0239] The silent comparison engine replaces the standard baseline in the original multidimensional fingerprint database with the environmentally compensated fingerprint baseline and performs pattern distance calculation processing.

[0240] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0241] In various embodiments, the hardware implementation of the technology can directly utilize existing smart devices, including but not limited to industrial control computers, PCs, smartphones, handheld devices, and floor-standing devices. Its input device preferably uses an on-screen keyboard, its data storage and computing modules utilize existing memory, calculators, and controllers, its internal communication modules utilize existing communication ports and protocols, and its remote communication utilizes existing GPRS networks, the World Wide Web, etc.

[0242] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0243] In the embodiments provided by this invention, it should be understood that the disclosed apparatus / terminal devices and methods can be implemented in other ways. For example, the apparatus / terminal device embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the shown or discussed mutual couplings or direct couplings or communication connections may be through some interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms. Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, i.e., they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0244] In the various embodiments of the present invention, the functional units can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated units can be implemented in hardware or as software functional units. If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention can implement all or part of the processes in the methods of the above embodiments, or it can be accomplished by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc.

Claims

1. A non-metallic energy metering box with a dual-use anti-theft verification code, characterized in that, It includes a non-metallic enclosure body, a dual-code verification module, a passive external monitoring unit, a physical locking and isolation unit, and an active reverse verification unit; The non-metallic enclosure is made of insulating composite material, and a distributed electromagnetic coupling array is embedded in the enclosure wall; the dual-code verification module is equipped with a unique identification code, which serves as a device legality authentication credential in the first verification mode and as an anti-electricity theft situational awareness key after being transformed by an algorithm in the second verification mode. The passive external monitoring unit is set in an isolated monitoring area with independent power supply outside the enclosure, and passively collects the operating characteristics of the metering unit inside the enclosure through non-contact electromagnetic field coupling. The physical interlocking isolation unit is linked with the passive external monitoring unit. When the operating characteristics are detected to deviate from the preset baseline threshold, the physical interlocking logic is triggered to irreversibly cut off the logical path between the metering unit and the external electrical interface, and at the same time, the second verification mode entry of the dual-code verification module is closed. The active reverse verification unit is activated after the physical interlocking isolation unit is triggered. The metering end actively sends a verification challenge to the power user. The verification challenge includes a time-varying sequence generated based on the second verification mode key of the dual-code verification module. The power user must send back a response through an independent physical channel within a specified time window; otherwise, an electricity theft alarm will be triggered.

2. The non-metallic energy metering box according to claim 1, characterized in that, The passive external monitoring unit includes a passive electromagnetic induction coil group, a silent comparison engine, and a dynamic threshold determiner: The passive electromagnetic induction coil group consists of at least three sets of passive electromagnetic induction coils arranged in a spatial triangular distribution, embedded in a concealed groove in the non-metallic frame outside the enclosure. The coils are not physically connected to any electrical circuit inside the enclosure. The passive electromagnetic induction coil group receives the spatial electromagnetic radiation signal leaked from the electrical circuit inside the enclosure, and performs spectral decomposition processing on the spatial electromagnetic radiation signal to obtain the fundamental frequency component, harmonic group component, and transient pulse component, and sends them to the silent comparison engine. The silent comparison engine performs mode distance calculation processing on the fundamental frequency component, harmonic group component, and transient pulse component to obtain the real-time mode distance value, and sends it to the dynamic threshold determiner. The threshold range in the dynamic threshold determiner is provided by the dynamic threshold generator in real time. The dynamic threshold generator receives historical electricity theft feature pattern database data and environmental stress mapping table data, and performs boundary fusion calculation on these two types of data to obtain the anomaly determination boundary under the current environmental conditions, and sends it to the dynamic threshold determiner as the determination basis. The dynamic threshold determiner performs threshold range out-of-bounds determination processing on the real-time mode distance value and the anomaly determination boundary to obtain the out-of-bounds determination result. When the out-of-bounds determination result exceeds the threshold range, the physical interlocking isolation unit is activated.

3. The non-metallic energy metering box according to claim 1, characterized in that, The physical interlocking isolation unit includes a one-time fusible isolation barrier and a logic channel closure; The one-time fuse-type isolation barrier is connected in series between the metering unit and the external electrical interface, and is used to irreversibly cut off the physical electrical path between the metering unit and the external electrical interface after being triggered. The logic channel closure device is linked to the one-time fuse-type isolation barrier, and is used to perform a logic closure action at the same time as or immediately after the one-time fuse-type isolation barrier is triggered. The logic closure action includes: transferring the second verification mode key of the dual-code verification module to an independent security domain outside the enclosure for storage through an emergency optical transmission channel, so as to disable the verification logic inside the enclosure. The physical cutting action of the one-time fuse-type isolation barrier and the logic closure action of the logic channel closure device together constitute a double lockout of the metering unit. The double lockout can only be released by physically replacing the one-time fuse-type isolation barrier and by remote authorization through the external independent security domain.

4. The non-metallic energy metering box according to claim 3, characterized in that, The emergency optical transmission channel includes a pre-embedded structural optical fiber and a mechanical optical switch; The pre-embedded structural fiber is embedded in the structural layer of the non-metallic composite material of the enclosure during the manufacturing of the enclosure. The pre-embedded structural fiber is in a physically disconnected state during normal communication of the enclosure. The physical disconnection state is maintained by the opaque optical isolation plugs formed by the hot-melt sealing process at both ends of the pre-embedded structural fiber. The mechanical optical switch is mechanically coupled to the pre-embedded optical fiber filament and is used to receive the trigger signal from the logic channel closure. Upon receiving the trigger signal, the mechanical optical switch performs a one-time optical path switching action, which includes driving the pre-embedded optical fiber filament from the physically disconnected state to a direct optical coupling state to form a one-time optical transmission link from the inside of the enclosure to the external security domain. The mechanical optical switch drives the pre-embedded optical fiber filament through irreversible mechanical deformation. After the pre-embedded optical fiber filament is switched to the direct optical coupling state, it cannot be restored to the physically disconnected state by the mechanical optical switch.

5. The non-metallic energy metering box according to claim 1, characterized in that, The active reverse verification unit includes a challenge generator, a heterogeneous dual-channel transmitter, a cross-backhaul receiver, and a time window controller. The challenge generator receives the second verification mode key and the instantaneous phase sampling value of the current power grid frequency from the dual-use verification module, performs time-varying sequence generation processing on these two types of data to obtain a single-time timeliness verification challenge code, and sends it to the heterogeneous dual-channel transmitter. The heterogeneous dual-channel transmitter performs parallel processing of power line carrier modulation and radio frequency modulation on the single-time timeliness verification challenge code to obtain dual heterogeneous challenge signals, and sends them to the power user through the power line carrier channel and the radio frequency channel respectively. The cross-backhaul receiver and the time window controller are set in a timing linkage. The time window controller starts a countdown when the challenge generator generates the challenge code, and outputs a receive enable signal to the cross-backhaul receiver during the countdown. During the validity period of the receive enable signal, the cross-backhaul receiver receives the response signal sent by the power user through a cross-backhaul channel different from the receiving channel, and performs response code consistency comparison and response timing compliance judgment processing on it to obtain the response judgment result.

6. The non-metallic energy metering box according to claim 1, characterized in that, The non-metallic energy metering box also includes a simulated sensor node array, which consists of multiple simulated sensor nodes arranged in the non-functional area of ​​the box surface. The non-functional area of ​​the box surface is the remaining area of ​​the box surface excluding the functional area. The functional area is the area necessary for operation and maintenance, where the passive electromagnetic induction coil group leads, communication interface, and status indicator lights of the passive external monitoring unit are arranged. The simulated sensor nodes are identical in appearance to the leads of the passive electromagnetic induction coil group, and are solid structures filled with epoxy resin. They have no electronic components, no electrical connections, no magnetic core, and do not have actual monitoring functions.

7. The non-metallic energy metering box according to claim 1, characterized in that, The insulating composite material of the non-metallic enclosure body has a dielectric constant gradient distribution characteristic. The enclosure wall consists of an outer low-dielectric-constant protective layer, a middle high-dielectric-constant coupling layer, and an inner low-dielectric-constant isolation layer; the thickness ratio of the three layers is 1:2:

1. The dielectric constant εr of the outer low-dielectric-constant protective layer is 3.0-3.5, the dielectric constant εr of the middle high-dielectric-constant coupling layer is 12.0-13.0, and the dielectric constant εr of the inner low-dielectric-constant isolation layer is 3.2-3.

8. The middle high-dielectric-constant coupling layer is composed of barium titanate uniformly dispersed in an epoxy resin matrix. The structure is composed of ceramic powder, which, after surface modification with a silane coupling agent, forms an insulating interface with an epoxy resin matrix. The high dielectric constant of the middle layer enhances the energy concentration of the internal leakage electromagnetic field in the middle layer, improving the coupling efficiency of the passive electromagnetic induction coil of the passive external monitoring unit to the internal signal. At the same time, the high volume resistivity of the middle layer blocks the conduction path of DC and power frequency currents, preventing short circuits or bypasses when external conductors directly contact the internal circuit. The three-layer structure is cured in one step during the molding process, and the interlayer forms an interface transition region through molecular chain entanglement and chemical bonding.

8. The non-metallic energy metering box according to claim 1, characterized in that, The algorithm transformation of the dual-use verification module includes a first verification mode and a second verification mode. In the first verification mode, the identification code is used to generate a 256-bit device fingerprint using the SM3 hash algorithm. The device fingerprint is stored in the read-only storage area of ​​the local security chip in the enclosure in the form of an immutable fuse array for device identity verification. In the second verification mode, the identification code is used to generate an anti-electricity theft situational awareness key through chaotic mapping transformation. The chaotic mapping transformation receives the identification code and the instantaneous sample value of the power grid frequency, and performs one-way chaotic mapping calculation processing on these two types of data to obtain the verification key.

9. The non-metallic energy metering box according to claim 1, characterized in that, It also includes a one-way optical isolation channel, a heartbeat frame generator, and a table-to-table consistency comparator; The unidirectional optical isolation channel connects the internal metering unit to the external independent monitoring domain, allowing only one-way signal transmission from the inside to the outside and blocking any signal injection from the outside to the inside. The heartbeat frame generator is located in the internal metering unit, receives the set of status parameters of the internal operating status, and performs compressed fingerprint generation processing on the set of status parameters to obtain an unforgeable heartbeat frame. The heartbeat frame is sent to the external monitoring domain through the unidirectional optical isolation channel. The consistency comparator receives the external electromagnetic features collected by the passive external monitoring unit and the internal electromagnetic features after decompression and restoration of the compressed fingerprint in the heartbeat frame, and performs consistency deviation calculation processing on these two types of data to obtain the consistency judgment result. When the consistency judgment result is that the external features are normal but the internal status is abnormal, an electricity theft alarm is triggered.

10. The non-metallic energy metering box according to claim 1, characterized in that, The non-metallic energy metering box adopts a layered independent defense architecture, which includes a contact physical defense layer and a non-contact electromagnetic defense layer. The contact-type physical defense layer consists of a physical locking isolation unit, which is used to irreversibly cut off the physical path between the metering unit and the external electrical interface in response to physical electricity theft that directly contacts the enclosure; the non-contact electromagnetic defense layer is executed in collaboration between a passive external monitoring unit and an active reverse verification unit, which is used to perform passive electromagnetic monitoring and active reverse verification in response to electromagnetic electricity theft in the area surrounding the enclosure. There is no control coupling between the contact physical defense layer and the non-contact electromagnetic defense layer. The triggering of the contact physical defense layer is directly driven by the boundary judgment result of the passive external monitoring unit, and does not depend on the verification result confirmation of the active reverse verification unit in the non-contact electromagnetic defense layer. Changes in the operating state of the non-contact electromagnetic defense layer do not affect the triggering response timing of the contact physical defense layer.

Images