Circuit autonomous inspection type box-type substation and inspection method thereof

Abstract

The present application relates to the technical field of circuit inspection, and discloses a circuit autonomous inspection type box-type substation and an inspection method thereof. The substation comprises a substation main body, a box top with a slidable shielding curtain, and a ventilation module and a dehumidification module embedded in the box wall. The low-voltage chamber is provided with an electric energy quality analysis module for real-time acquisition of operating parameters. The inspection method calculates the actual heat dissipation by analyzing the temperature difference of the air inlet / outlet, and calculates the theoretical heat generation in combination with the load current and harmonic spectrum. When the heat generation is significantly lower than the heat dissipation, an abnormally high temperature self-inspection is triggered: the humidity risk index is calculated by combining the ambient temperature and humidity, and if the threshold is exceeded, the insulation is determined to be abnormal, the system is automatically switched from the heat dissipation mode to the electric heating and dehumidification mode, and a maintenance instruction is sent. The present application realizes the transformation from passive maintenance to active early warning, improves the operation and maintenance response speed and equipment reliability, and the shielding curtain structure provides convenience for outdoor maintenance.

Description

Technical Field

[0001] This invention relates to the field of circuit inspection technology, and in particular to a self-inspecting prefabricated substation and its inspection method. Background Technology

[0002] As a key piece of equipment in the power system, the stable operation of prefabricated substations is crucial to the reliability of power supply. Traditional prefabricated substations face several problems during long-term operation: for example, in humid environments, condensation easily forms inside the substation, reducing insulation performance and threatening equipment safety. Existing technologies mostly use fixed dehumidification devices, lacking coordinated control with temperature, humidity, and equipment operating status. Furthermore, maintenance personnel lack shade and rain protection when working outdoors, affecting work efficiency and safety. Therefore, there is an urgent need for a prefabricated substation with autonomous inspection, intelligent temperature and humidity control, and maintenance assistance functions to improve its operational reliability, energy efficiency, and maintenance convenience. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a circuit autonomous inspection type box-type substation and its inspection method to solve the above-mentioned technical problem.

[0004] To address the aforementioned technical problems, this application provides, on the one hand, a circuit autonomous inspection type prefabricated substation, including a substation body with a box top on top. The box top has a slidable, extendable shielding curtain inside. A ventilation module and a dehumidification module are embedded in the outer wall of the substation body. Each ventilation and dehumidification module includes a fixing frame, a fan, and louvers. The fixing frame of the dehumidification module also contains an mounting frame, and the mounting frame contains a heating wire, which corresponds to the airflow position of the fan. A power quality analysis module is located in the low-voltage chamber of the substation body, used to collect real-time operating parameters of the prefabricated substation during operation and to initiate circuit inspection operations when abnormal parameters occur.

[0005] Optionally, the upper surface of the box top is arranged in an inverted triangle, a partition plate is installed in the center of the inside of the box top, and drive screws are symmetrically installed on both sides of the partition plate.

[0006] Optionally, a drive rod is sleeved on the outside of the drive screw, the drive rod slides out along the inside of the top of the box, and the partition plate divides the inside of the top of the box into two independent mounting slots.

[0007] Optionally, the drive rod has a threaded hole inside that is adapted to the drive screw, the partition plate has a motor connected to the drive screw installed inside, the end of the drive rod away from the drive screw is fixedly connected to a crossbeam, and the drive rods are symmetrically distributed on both sides of the crossbeam to form a U-shaped structure.

[0008] Optionally, the crossbeam is adapted to the mounting groove, and the crossbeam retracts with the drive rod to close the mounting groove, and the curtain is fixedly connected to the drive rod and the crossbeam.

[0009] Optionally, a camera is installed on the outer wall of the substation body. The camera transmits the signals of the maintenance personnel to the controller, which then controls the motor to start and open the shielding curtain.

[0010] On the other hand, this application provides an inspection method for a circuit autonomous inspection type box-type substation. Both the ventilation module and the dehumidification module are equipped with temperature sensors. In the heat dissipation state, the ventilation module is the air inlet and the dehumidification module is the air outlet. The heat dissipation operation is performed according to the preset power. The heating wire in the dehumidification module is not activated during the heat dissipation period.

[0011] During heat dissipation, the temperature fluctuation curves fed back by the temperature sensors on the ventilation module and dehumidification module are continuously acquired. Then, the temperature difference fluctuation curve between the air inlet and outlet of the transformer box is calculated, and it is substituted into the heat dissipation calculation model to calculate the total heat dissipation within the current preset time period. The heat dissipation calculation model is a neural network model used to characterize the mapping relationship between the temperature difference between the air inlet / outlet of the transformer box, the wind speed at the air inlet / outlet, and the total heat dissipation. It is obtained through a large amount of historical data for verification and training.

[0012] Obtain the rated load loss, rated current, and load current curve within a preset time period. Based on the ratio of the load current value to the rated current in the load current curve and the rated load loss, calculate the theoretical load loss of the transformer under harmonic-free conditions. The rated load loss represents the loss measured at rated current and rated frequency, including the DC resistance loss of the winding and the eddy current loss considered in the design. This part of the loss is the source of the transformer heat source and can be regarded as the heat generated by the transformer under ideal conditions.

[0013] The power quality analysis module located in the low-voltage area collects the current and voltage harmonic spectrum at the transformer port within a preset time period, and calculates the additional harmonic loss of the transformer based on the current and voltage harmonic spectrum.

[0014] The theoretical load loss and harmonic additional loss are summed. If the sum is less than 80%-85% of the total heat dissipation, the abnormal high temperature self-inspection operation is triggered.

[0015] The abnormal high temperature self-inspection operation includes:

[0016] Meteorological data of the current location of the prefabricated substation is obtained through a communication module located in the low-voltage room. The meteorological data includes ambient temperature and ambient humidity.

[0017] The temperature difference between the ambient temperature and the temperature sensor reading on the dehumidification module is calculated. Based on the temperature difference and ambient humidity, a moisture risk index is calculated using a weighted algorithm. If the moisture risk index exceeds a preset threshold, the transformer insulation sleeve is determined to be abnormally hot. At this point, the prefabricated substation is switched from heat dissipation mode to dehumidification mode. In dehumidification mode, the dehumidification module acts as the air inlet and the ventilation module acts as the air outlet. During dehumidification, the heating wire in the dehumidification module is activated to accelerate the evaporation of moisture on the upper surface of the transformer and send an insulation abnormality command so that the back-end service personnel can generate the corresponding prefabricated substation insulation maintenance task.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects:

[0019] The circuit autonomous inspection-type prefabricated substation described in this invention collects operating parameters in real time through a power quality analysis module in the low-voltage room. Combined with a heat dissipation model and harmonic loss analysis, it can automatically determine heat dissipation anomalies and insulation status, triggering a high-temperature self-inspection program. This system can integrate real-time electrical data and environmental meteorological information to accurately assess condensation risks and equipment health, realizing a shift from passive maintenance to proactive early warning, significantly improving operation and maintenance response speed and equipment reliability.

[0020] Secondly, the design of the protective curtain provides maintenance personnel with excellent shelter from wind and rain, enabling them to carry out maintenance work smoothly even in inclement weather. This avoids maintenance delays caused by weather conditions and improves maintenance progress and efficiency. At the same time, it creates a relatively comfortable working environment for maintenance personnel, reducing their workload and contributing to improved maintenance quality.

[0021] Secondly, in the heat dissipation assessment, not only the basic load loss is considered, but also the harmonic spectrum data collected by the power quality analysis module is introduced to calculate the additional harmonic loss, so that the heat generation model is closer to the actual operating conditions, improves the accuracy of anomaly diagnosis, and provides a reliable basis for transformer condition assessment and life prediction. Attached Figure Description

[0022] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate embodiments of the invention and, together with the specification, further serve to explain the principles of the invention and enable those skilled in the art to practice and use the invention.

[0023] Figure 1 A schematic diagram of the three-dimensional structure of a self-inspecting prefabricated substation.

[0024] Figure 2 A schematic diagram of the structure of the curtain in its unfolded state;

[0025] Figure 3 This is a schematic diagram of the dehumidification module structure;

[0026] Figure 4 A schematic diagram of the structure in the extended state of the drive rod;

[0027] Figure 5 This is a schematic diagram of the drive rod in its retracted state.

[0028] Figure label:

[0029] 1. Substation main body; 2. Box top; 3. Ventilation module; 4. Dehumidification module; 5. Crossbeam; 6. Drive rod; 7. Shielding curtain; 8. Fixing frame; 9. Louver; 10. Fan; 11. Heating wire; 12. Mounting frame; 13. Partition plate; 14. Mounting groove; 21. Drive screw. Detailed Implementation

[0030] The circuit autonomous inspection type box-type substation and its inspection method provided by the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should also be noted that, to make the embodiments more detailed, the following embodiments are the best and preferred embodiments, and those skilled in the art can use other alternative methods to implement some well-known technologies; moreover, the accompanying drawings are only for more specific description of the embodiments and are not intended to specifically limit the present invention.

[0031] It should be noted that the use of terms such as "an embodiment," "an embodiment," "an exemplary embodiment," and "some embodiments" in the specification indicates that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, when describing a specific feature, structure, or characteristic in conjunction with embodiments, the implementation of such feature, structure, or characteristic in conjunction with other embodiments, whether or not explicitly described, should be within the knowledge of those skilled in the art.

[0032] Example 1:

[0033] like Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a circuit autonomous inspection type box-type substation, including a substation body 1, a box top 2 on the top of the substation body 1, and a slidable and extendable shielding curtain 7 inside the box top 2; a ventilation module 3 and a dehumidification module 4 are provided on the outer wall of the substation body 1, and the ventilation module 3 and the dehumidification module 4 are embedded.

[0034] like Figure 3 As shown, both the ventilation module 3 and the dehumidification module 4 include a fixed frame 8, a fan 10 and louvers 9. The fixed frame 8 of the dehumidification module 4 is also provided with an installation frame 12. The installation frame 12 is provided with an electric heating wire 11 inside, and the electric heating wire 11 corresponds to the air blowing position of the fan 10.

[0035] like Figure 4 , Figure 5As shown, the upper surface of the enclosure top 2 is designed as an inverted triangle. A partition plate 13 is centrally installed inside the enclosure top 2, and drive screws 21 are symmetrically installed on both sides of the partition plate 13. A drive rod 6 is fitted onto the outside of the drive screw 21, sliding out along the interior of the enclosure top 2. The partition plate 13 divides the interior of the enclosure top 2 into two independent mounting slots 14. The drive rod 6 has threaded holes adapted to the drive screw 21. A motor connected to the drive screw 21 is installed inside the partition plate 13. A crossbeam 5 is fixedly connected to the end of the drive rod 6 away from the drive screw 21. The drive rods 6 are symmetrically distributed on both sides of the crossbeam 5, forming a U-shaped structure. The crossbeam 5 fits into the mounting slot 14, and the crossbeam 5 retracts with the drive rod 6 to close the mounting slot 14. The shielding curtain 7 is fixedly connected to the drive rod 6 and the crossbeam 5. A camera is installed on the outer wall of the substation main body 1. The camera transmits the signals taken by maintenance personnel to the controller, which then controls the motor to start and unfold the shielding curtain 7.

[0036] Working principle of blind curtain 7

[0037] Cameras installed on the outer wall of the substation main body 1 monitor the surrounding environment in real time. When maintenance personnel are detected entering the maintenance area, the camera transmits the captured signal to the controller, causing the shielding curtain 7 to unfold. Upon receiving the signal, the controller starts the motor inside the partition plate 13, which drives the drive screw 21 to rotate. Since the drive rod 6 has a threaded hole that matches the drive screw 21, the rotation of the drive screw 21 causes the drive rod 6 to slide outward along the inside of the top of the enclosure 2. A crossbeam 5 is fixedly connected to the end of the drive rod 6 away from the drive screw 21. The drive rods 6 are symmetrically distributed and combined to form a U-shaped structure. As the drive rod 6 slides out, the crossbeam 5 also moves, simultaneously causing the shielding curtain 7, which is fixedly connected to the drive rod 6 and the crossbeam 5, to unfold, providing a sheltered working environment for maintenance personnel. Once the maintenance work is completed and the maintenance personnel leave the maintenance area, the camera transmits the signal to the controller again. The controller controls the motor to rotate in the opposite direction, drives the screw 21 to rotate in the opposite direction, and the drive rod 6 retracts inward. The crossbeam 5 moves accordingly, and the curtain 7 also retracts, closing the mounting slot 14.

[0038] Example 2:

[0039] Before explaining this embodiment, it is necessary to briefly describe some industry common sense, such as... Figure 1 As shown, a prefabricated substation typically consists of three compartments: a low-voltage compartment on the left, a high-voltage compartment on the right, and a transformer compartment in the middle. Figure 1 As shown, in this embodiment, both the ventilation module 3 and the dehumidification module 4 are located on the side wall of the middle transformer chamber;

[0040] The main heat sources of a transformer are the windings and core inside the transformer. However, under some abnormal conditions, multiple insulating bushings at the top of the transformer can also become heat sources. For example, condensation caused by prolonged exposure to a humid environment or a large temperature difference between the inside and outside of the transformer can trigger a vicious cycle of heat generation in the insulating bushings. The specific process is as follows: the loss of the insulating medium increases dramatically, generating heat and temperature rise, accelerating insulation aging and evaporating moisture to form bubbles, inducing partial discharge, further damaging the insulation strength, and ultimately leading to insulation breakdown or surface flashover. In this cycle, the surface temperature of the insulating bushings will rise significantly, thereby increasing the heat generation of the entire transformer chamber.

[0041] This embodiment is based on embodiment 1 and is used to provide an inspection method for a circuit autonomous inspection box-type substation. Both the ventilation module 3 and the dehumidification module 4 are equipped with temperature sensors. In the heat dissipation state, the ventilation module 3 is the air inlet and the dehumidification module 4 is the air outlet. The heat dissipation operation is performed according to the preset power. During the heat dissipation period, the heating wire 11 in the dehumidification module 4 is not activated. That is, at this time, the air volume enters from the bottom of the substation body 1 and exits from the top of the substation body 1.

[0042] During heat dissipation, the temperature fluctuation curves fed back by temperature sensors installed on ventilation module 3 and dehumidification module 4 are continuously acquired. The temperature difference fluctuation curve between the air inlet and outlet of the transformer housing is then calculated and substituted into the heat dissipation calculation model to calculate the total heat dissipation within the current preset time period. This heat dissipation calculation model is a neural network model characterizing the mapping relationship between the temperature difference between the transformer housing's air inlet / outlet, the air velocity at the air inlet / outlet, and the total heat dissipation. This model is trained and validated using a large amount of historical data. Generally, the above-mentioned heat dissipation statistics method calculates the unit heat dissipation corresponding to the entire transformer room based on the ventilation speed, the temperature difference between the air inlet and outlet, and the temperature at the air outlet. However, due to factors such as the installation location of the transformer, the air inlet, and the air outlet, it is impossible to quantize this using an ensemble model. Therefore, a neural network model is introduced. Based on a large amount of experimental data on heat dissipation and heat generation ratios, a relationship between the temperature difference between the air inlet and outlet and the transformer's heat dissipation is constructed. This relationship is an empirical correlation, which will not be elaborated here. With the popularization of big data analysis algorithms and artificial intelligence algorithms, this nonlinear, strongly correlated multi-parameter quantization has become a common technical means.

[0043] Obtain the transformer's rated load loss, rated current, and load current curve over a preset time period. The rated load loss and rated current can be obtained from the transformer nameplate or test reports provided by the transformer supplier. Based on the ratio of the load current value to the rated current in the load current curve and the rated load loss, calculate the theoretical load loss of the transformer under harmonic-free conditions. The rated load loss represents the loss measured at rated current and rated frequency, including the DC resistance loss of the windings and the eddy current loss considered in the design. This part of the loss is the source of the transformer's heat source and can be regarded as the transformer under ideal conditions. The heat generation of the transformer is calculated. The ideal state refers to the additional losses caused by occasional transformer harmonics. The rated load loss is the maximum heat generation of the transformer winding and core provided by the manufacturer under the rated current. Then, the theoretical heat generation of the transformer winding and core is calculated based on the ratio of the load current value to the rated current. It should be noted that the square of the load current value is linearly related to the heat generation, that is, the heat generation is roughly linearly related to I²R, where I is the current load current. By calculating the ratio of the load current value to the rated current, the ratio of the current heat generation to the maximum heat generation can be calculated.

[0044] The power quality analysis module located in the low-voltage area collects the current and voltage harmonic spectrum at the transformer port within a preset time period. The additional harmonic loss of the transformer is calculated based on the current and voltage harmonic spectrum. The specific calculation method of the additional harmonic loss is detailed in Example 3 and will not be elaborated here.

[0045] Summing the theoretical load loss and harmonic additional loss, if the sum is less than 80%-85% of the total heat dissipation, triggers the abnormal high temperature self-inspection operation. This indicates that there are other heat sources in the transformer room that cause the proportion of heat generated by the theoretical load loss and harmonic additional loss to the total heat dissipation to decrease, indicating that there are other significant heat sources on the transformer. Based on historical accident experience, this heat source is most likely caused by abnormal high temperature of the transformer's insulating bushing. Abnormal high temperature of the insulating bushing is usually caused by long-term humid environment. Therefore, once abnormal high temperature is detected in other parts of the transformer, it is usually first checked whether there is a relatively humid environment in the current transformer room. Since there is a lack of corresponding humidity sensors, this judgment can be indirectly and comprehensively judged by obtaining the ambient humidity and ambient temperature at the location of the box-type substation and the temperature difference between the ambient temperature and the dehumidification module 4. When it is determined that the current environment is likely to be humid and there is abnormal high temperature in other parts of the transformer, it can be determined that the current transformer's insulating bushing has abnormal aging, resulting in low insulation performance. It is necessary to arrange for the corresponding maintenance personnel to replace the insulating bushing on site. The specific implementation method of the above principle can be:

[0046] The abnormal high temperature self-inspection operation includes:

[0047] Meteorological data of the current location of the prefabricated substation is obtained through a communication module located in the low-voltage room. The meteorological data includes ambient temperature and ambient humidity.

[0048] The temperature difference between the ambient temperature and the temperature output from dehumidification module 4 is calculated. Based on the temperature difference and ambient humidity, a moisture risk index is calculated using a weighted algorithm. If the moisture risk index exceeds a preset threshold, the transformer insulation sleeve is determined to be abnormally hot. At this point, the prefabricated substation is switched from heat dissipation mode to dehumidification mode. In dehumidification mode, dehumidification module 4 acts as the air inlet, and ventilation module 3 acts as the air outlet. During dehumidification, the heating wire 11 in dehumidification module 4 is activated to accelerate the evaporation of moisture on the upper surface of the transformer and sends an insulation abnormality command so that backend service personnel can generate a corresponding prefabricated substation insulation maintenance task. When the temperature difference between the transformer room and the external environment is large, and the external humidity is high, condensation will occur on the transformer surface. The water stains formed by condensation may induce electrical insulation faults such as flashover or partial discharge when the insulation capacity of the insulation sleeve is weak, thus leading to abnormally high temperatures in the insulation sleeve.

[0049] Example 3:

[0050] This embodiment is based on Embodiment 2 and is used to further illustrate the specific calculation method for transformer harmonic additional losses:

[0051] Obtain the current and voltage harmonic spectrum at the transformer port, the spectrum comprising a current sequence and a voltage sequence from the fundamental wave to the Nth harmonic;

[0052] Based on the current sequence and the pre-stored transformer fundamental load loss value, the total winding loss, including harmonic effects, is calculated. Specifically, the total winding loss is equal to the fundamental load loss value multiplied by a first harmonic loss factor; wherein the first harmonic loss factor is determined by the following formula:

[0053] F_HL = Σ [ (I_h / I_1)^2 × h^p ] , where the summation variable h ranges from 1 to N;

[0054] In the formula, I_h is the effective value of the h-th harmonic current, I_1 is the effective value of the fundamental current, and p is an exponential constant greater than 0;

[0055] Based on the voltage sequence and the pre-stored transformer fundamental no-load loss value, calculate the total core loss including harmonic effects;

[0056] The total core loss is equal to the fundamental no-load loss value multiplied by the second harmonic loss factor;

[0057] The second harmonic loss factor is determined by the following formula:

[0058] F_HL_Fe = Σ [ (U_h / U_1)^2 × h^q ] , where the summation variable h ranges from 1 to N;

[0059] In the formula, U_h is the effective value of the h-th harmonic voltage, U_1 is the effective value of the fundamental voltage, and q is an exponential constant greater than 1;

[0060] The total winding loss and the total core loss are summed to obtain the total loss of the transformer under the harmonic spectrum, and then output.

[0061] This embodiment provides a standardized and engineering-implementable method for calculating transformer harmonic additional losses. This method transforms the complex harmonic electromagnetic field problem into an algebraic calculation problem based on measured or simulated spectral data and a standard loss reduction model. By defining two core harmonic loss factors (F_HL, F_HL_Fe) and their key exponents (p, q), efficient and unified quantification of the increments in winding eddy current losses and core losses is achieved. The final output total loss value can be directly used for transformer thermal operation management, and is particularly suitable for evaluating the actual operating state of transformers under nonlinear load conditions.

[0062] This invention encompasses any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of this invention. To provide the public with a thorough understanding of this invention, specific details are described in detail in the following preferred embodiments; however, those skilled in the art will fully understand the invention even without these details. Furthermore, to avoid unnecessary misunderstanding of the essence of this invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0063] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for inspecting a self-inspecting prefabricated substation, characterized in that: The circuit self-inspection type box-type substation includes a substation body (1), a box top (2) on the top of the substation body (1), and a sliding and extendable shielding curtain (7) inside the box top (2); a ventilation module (3) and a dehumidification module (4) are provided on the outer wall of the substation body (1), the ventilation module (3) and the dehumidification module (4) are embedded, the ventilation module (3) and the dehumidification module (4) both include a fixed frame (8), a fan (10) and louvers (9), the fixed frame (8) of the dehumidification module (4) is also provided with an installation frame (12), the installation frame (12) is provided with an electric heating wire (11), the electric heating wire (11) corresponds to the blowing position of the fan (10); a power quality analysis module is provided in the low-voltage room of the substation body (1) to collect the operating parameters of the box-type substation in real time during the operation process, and to start the circuit inspection operation when the parameters are abnormal. Temperature sensors are provided on both the ventilation module (3) and the dehumidification module (4). In the heat dissipation state, the ventilation module (3) is the air inlet and the dehumidification module (4) is the air outlet. The heat dissipation operation is performed according to the preset power. The heating wire (11) in the dehumidification module (4) is not activated during the heat dissipation period. During the heat dissipation period, the temperature fluctuation curves fed back by the temperature sensors on the ventilation module (3) and dehumidification module (4) are continuously acquired, and then the temperature difference fluctuation curve between the air inlet and outlet of the transformer box is calculated. The curve is then substituted into the heat dissipation calculation model to calculate the total heat dissipation in the current preset time period. The heat dissipation calculation model is a neural network model used to characterize the mapping relationship between the temperature difference between the air inlet and outlet of the transformer box, the wind speed at the air inlet and outlet, and the total heat dissipation. It is obtained through a large amount of historical data verification and training. Obtain the rated load loss, rated current, and load current curve within a preset time period. Based on the ratio of the load current value to the rated current in the load current curve and the rated load loss, calculate the theoretical load loss of the transformer under harmonic-free conditions. The rated load loss represents the loss measured at rated current and rated frequency, including the DC resistance loss of the winding and the eddy current loss considered in the design. This part of the loss is the source of the transformer heat source and can be regarded as the heat generated by the transformer under ideal conditions. The power quality analysis module located in the low-voltage area collects the current and voltage harmonic spectrum at the transformer port within a preset time period, and calculates the additional harmonic loss of the transformer based on the current and voltage harmonic spectrum. The theoretical load loss and harmonic additional loss are summed. If the sum is less than 80%-85% of the total heat dissipation, the abnormal high temperature self-inspection operation is triggered. The abnormal high temperature self-inspection operation includes: Meteorological data of the current location of the prefabricated substation is obtained through a communication module located in the low-voltage room. The meteorological data includes ambient temperature and ambient humidity. The difference between the ambient temperature and the temperature output from the dehumidification module (4) is calculated, and the humidity risk index is calculated by weighted algorithm based on the temperature difference and ambient humidity. If the humidity risk index is greater than the preset threshold, the transformer insulation sleeve is judged to be abnormally hot. At this time, the box-type substation is switched from heat dissipation state to dehumidification state. In the dehumidification state, the dehumidification module (4) is the air inlet and the ventilation module (3) is the air outlet. During the dehumidification period, the heating wire (11) in the dehumidification module (4) is activated to accelerate the evaporation of moisture on the upper surface of the transformer and send an insulation abnormality command so that the back-end service personnel can generate the corresponding box-type substation insulation maintenance task. The specific calculation method for transformer harmonic additional losses is as follows: Obtain the current and voltage harmonic spectrum at the transformer port, the spectrum comprising a current sequence and a voltage sequence from the fundamental wave to the Nth harmonic; Based on the current sequence and the pre-stored transformer fundamental load loss value, the total winding loss, including harmonic effects, is calculated. Specifically, the total winding loss is equal to the fundamental load loss value multiplied by a first harmonic loss factor; wherein the first harmonic loss factor is determined by the following formula: F_HL = Σ [ (I_h / I_1)^2 × h^p ] , where the summation variable h ranges from 1 to N; In the formula, I_h is the effective value of the h-th harmonic current, I_1 is the effective value of the fundamental current, and p is an exponential constant greater than 0; Based on the voltage sequence and the pre-stored transformer fundamental no-load loss value, calculate the total core loss including harmonic effects; The total core loss is equal to the fundamental no-load loss value multiplied by the second harmonic loss factor; The second harmonic loss factor is determined by the following formula: F_HL_Fe = Σ [ (U_h / U_1)^2 × h^q ] , where the summation variable h ranges from 1 to N; In the formula, U_h is the effective value of the h-th harmonic voltage, U_1 is the effective value of the fundamental voltage, and q is an exponential constant greater than 1; The total winding loss and the total core loss are summed to obtain the total loss of the transformer under the harmonic spectrum, and then output.

2. The inspection method for a circuit autonomous inspection type prefabricated substation according to claim 1, characterized in that, The upper surface of the box top (2) is set in an inverted triangle. A partition plate (13) is installed in the center of the box top (2). Drive screws (21) are symmetrically installed on both sides of the partition plate (13).

3. The inspection method for a circuit autonomous inspection type prefabricated substation according to claim 2, characterized in that, The drive screw (21) is fitted with a drive rod (6), which slides out along the inside of the top of the box (2). The partition plate (13) divides the inside of the top of the box (2) into two independent mounting slots (14).

4. The inspection method for a circuit autonomous inspection type prefabricated substation according to claim 3, characterized in that, The drive rod (6) has a threaded hole that is adapted to the drive screw (21). The partition plate (13) is equipped with a motor that connects to the drive screw (21). The end of the drive rod (6) away from the drive screw (21) is fixedly connected to a crossbeam (5). The drive rod (6) is symmetrically distributed on both sides of the crossbeam (5) and combined to form a U-shaped structure.

5. The inspection method for a circuit autonomous inspection type prefabricated substation according to claim 4, characterized in that, The crossbeam (5) is adapted to the mounting groove (14). The crossbeam (5) retracts with the drive rod (6) to close the mounting groove (14). The curtain (7) is fixedly connected to the drive rod (6) and the crossbeam (5).

6. The inspection method for a circuit autonomous inspection type prefabricated substation according to claim 5, characterized in that, A camera is installed on the outer wall of the main body (1) of the substation. The camera transmits the shooting signal of the maintenance personnel to the controller, and the controller controls the motor to start and drive the curtain (7) to unfold.

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