Box transformer control and protection device

Abstract

The application provides a box transformer measurement and control protection device, and relates to the field of box transformer measurement and control protection, which comprises an alternating current conversion module, a CPU module, an outgoing module, an incoming module and a man-machine dialogue module; the alternating current conversion module is used for converting power signals; the CPU module integrates data sampling processing, communication and protection functions; and the man-machine dialogue module realizes the operation interaction between people and the device. The box transformer measurement and control protection device further comprises a communication module and a standby module; the communication module is used for long-distance data transmission; and the standby module is used for expanding functions; the alternating current conversion module comprises a current transformer TA and a voltage transformer TV, which are used for converting the secondary side current and voltage signals of the system TA and TV into weak current signals, so that the CPU module can collect and process the signals and play a role in strong and weak current isolation. Through the integration of the alternating current conversion module, the CPU module, the incoming and outgoing modules and the man-machine dialogue module, the function boundaries and signal interaction logic of each module are clear, and the deep cooperation of data sampling processing, communication, control and protection functions is realized.

Description

Technical Field

[0001] This invention relates to the field of transformer substation measurement and control protection technology, specifically to a transformer substation measurement and control protection device, which is applied to the remote management and automated monitoring of all information on the high and low voltage sides of wind power and photovoltaic transformer substations. Background Technology

[0002] In the wind and solar power sectors, prefabricated transformers (PGCs) are key equipment for power conversion and transmission, and their real-time monitoring and fault protection are crucial to the stability of the entire power generation system. Currently, the measurement, control, and protection systems for PGCs have the following shortcomings:

[0003] Traditional monitoring methods are difficult to achieve remote and automated centralized management. Maintenance personnel need to frequently conduct on-site inspections, which is not only inefficient but may also lead to the expansion of faults due to untimely inspections.

[0004] The CPU module's protection features lack specific design.

[0005] The control of air-cooled devices often relies on manual experience or simple threshold triggering, lacking an intelligent decision-making mechanism based on multiple factors such as flow field and temperature. This can easily lead to insufficient heat dissipation or excessive energy consumption, affecting the service life and economy of the transformer substation. Summary of the Invention

[0006] The present invention provides a transformer substation monitoring and protection device to solve at least one of the technical problems mentioned in the background art.

[0007] To address the aforementioned technical problems, this invention discloses a transformer substation monitoring and protection device, comprising a chassis, a control panel mounted on the chassis, and further comprising:

[0008] AC converter module, CPU module, output module, input module, human-computer interaction module;

[0009] The AC conversion module is used to convert power signals. The CPU module integrates data sampling and processing, communication and protection functions. The input and output modules are responsible for signal input and output control. The human-machine interface module realizes the operation interaction between people and the device.

[0010] Preferably, it also includes: a communication module, which is used for long-distance data transmission, and a backup module for expanding functions. All modules cooperate through signal interaction to jointly realize the measurement, control and protection of the transformer substation system.

[0011] The AC conversion module includes a current converter (TA) and a voltage converter (TV), which are used to convert the secondary current and voltage signals of the system's TA and TV into weak electrical signals for the CPU module to acquire and process, and also serve as a strong-weak electrical isolation mechanism. The AC conversion module also integrates the device's power supply module.

[0012] Preferably, the CPU module includes a protection submodule, which includes:

[0013] Ratio differential protection unit: used to protect transformers; can detect internal phase-to-phase short circuits, high-voltage side single-phase ground faults and turn-to-layer short circuits; and effectively cope with inrush current, over-excitation operating conditions and abnormal current transformer conditions.

[0014] Differential current instantaneous trip protection unit: It operates instantaneously when the differential current of any phase exceeds the differential current instantaneous trip setting value;

[0015] Differential current over-limit alarm unit: When the differential current of any phase exceeds the differential current over-limit threshold for a duration exceeding the differential current over-limit delay setting, a differential current over-limit alarm message is issued.

[0016] Three-stage time-limited current protection unit: It is equipped with time-limited overcurrent protection in stage I, stage II, and stage III. When the time-limited overcurrent protection in stage I, stage II, and stage III is activated, the TV disconnection detection protection is blocked.

[0017] TA anomaly detection unit: The instantaneous TA anomaly alarm and lockout function is determined when the differential current exceeds 0.5 times the minimum differential operating current; to prevent false lockout of TA during instantaneous operation, instantaneous TA anomaly alarm determination will not be performed if any of the following conditions are met:

[0018] 1) The maximum phase current on each side is greater than 1.2Ie;

[0019] 2) Before startup, the maximum phase current on this side is less than 0.5 times the differential startup current;

[0020] The current transformer (CT) is considered to be abnormal if the current on either side simultaneously meets the following conditions:

[0021] 1) The open-circuit phase current is less than 0.05A;

[0022] 2) At least one phase current in the three-phase current on this side remains unchanged;

[0023] The control word allows you to select whether to block the ratio differential protection while simultaneously triggering an instantaneous TA abnormal alarm signal.

[0024] Preferably, the protection submodule further includes: an overload protection unit, a zero-sequence current protection unit, an undervoltage protection unit, an overvoltage protection unit, a TV disconnection alarm unit, a TA disconnection alarm unit, and a high-voltage FC overvoltage interlock.

[0025] Preferably, the device's input power supply is AC / DC compatible, the device's auxiliary power supply is AC / DC compatible, the maximum input voltage reaches 600V, and the device's switch input circuit power supply is AC / DC compatible, making it suitable for systems with or without DC power supply.

[0026] Preferably, the chassis is divided into several zones, each zone corresponding to an air-cooling unit; the transformer substation monitoring and protection device also includes: an air-cooling control device, comprising:

[0027] Temperature Detection Module 1: The surface temperature of the key heating components in each zone is measured by Temperature Detection Module 1;

[0028] Temperature detection module 2: Used to detect the temperature of the air intake area of ​​the air-cooled device;

[0029] Regional detection devices: used to detect ambient wind speed and ambient air pressure within the zone;

[0030] Flow field coupling analysis module: used to determine the wind speed-pressure synchronization coefficient based on ambient air pressure and ambient wind speed, and to determine the flow field dynamics-flow state coupling coefficient based on the wind speed-pressure synchronization coefficient, ambient air pressure, and ambient flow velocity;

[0031] Early warning module 1: Used to issue an early warning when the surface temperature of any critical heat-generating device is greater than k times the corresponding initial heat dissipation trigger temperature, before early warning module 2 issues an early warning.

[0032] Calibration control module: When the early warning module issues an early warning, it controls the air-cooled device to operate at rated output power for the pre-inspection period. Based on the detection results of the detection device within the area during the pre-inspection period, it obtains the initial flow field dynamic-fluid state coupling coefficient determined by the flow field coupling analysis module.

[0033] Heat dissipation analysis module: used to determine the heat dissipation effect coefficient based on the initial flow field dynamic-fluid regime coupling coefficient;

[0034] Temperature adjustment module: used to determine the heat dissipation trigger temperature of key heat-generating components after adjustment based on the initial flow field dynamic-fluid state coupling coefficient when the heat dissipation effect coefficient is less than the corresponding reference value;

[0035] Early warning module 2: It is used to issue an early warning when the surface temperature of any key heat-generating component exceeds the corresponding adjusted heat dissipation trigger temperature of the key heat-generating component, and to remind the corresponding air-cooling device to adjust the control parameters or start the air-cooling device.

[0036] Preferred options also include:

[0037] Operation detection module: used to detect the operating parameters of the air-cooled unit, including: input power and temperature of key components;

[0038] Temperature analysis module: used to determine the temperature coefficient based on the temperature of key components of the air-cooled device;

[0039] Time Analysis Module: Used when the Nth warning from Target Warning Module 2 is greater than or equal to 2; to determine the actual time interval between the current warning and the previous warning from Target Warning Module 2, and to determine the interval matching coefficient corresponding to the Nth warning from Target Warning Module 2;

[0040] Matrix construction module: used to divide the flow field dynamics-fluid state coupling coefficient into multiple first intervals and the temperature coefficient into multiple second intervals. A two-dimensional matrix is ​​constructed with the first interval as rows and the second interval as columns. The intersection of each row and each column in the two-dimensional matrix forms a matrix unit. Each matrix unit is configured with a unique air-cooling control strategy.

[0041] Prediction module: used to collect historical data that is within the same input power range as the target air-cooled device before the Nth warning and whose historical time interval matching coefficient is qualified after historical adjustment: including the historical time interval matching coefficient before historical adjustment, the input power of the air-cooled device before historical adjustment and the heat dissipation effect coefficient, to determine the target adjustment coefficient, and to determine the preliminary target input power of the target air-cooled device after the Nth warning based on the target adjustment coefficient;

[0042] Air-cooled control analysis module: Used to adjust the control strategy corresponding to the heat dissipation risk level output by the matrix construction module, correct the initial target input power of the target air-cooled device after the Nth warning, and finally determine the target input power of the target air-cooled device after the Nth warning.

[0043] Preferably, it also includes a current converter detection device, which includes:

[0044] Power module acquisition module: used to acquire the current and temperature of the power module of the current converter;

[0045] Response Analysis Module: Used to determine the current coefficient and thermal coefficient of the power module based on the current converter and the average value of all key temperature regions, and combine the current coefficient and thermal coefficient to determine the dynamic response coefficient;

[0046] Early warning module 3: Used to issue an early warning when the dynamic response coefficient exceeds the corresponding allowable range;

[0047] Temperature analysis module: used to determine the temperature gradient based on the temperature of the key temperature region of the power module and to determine the thermal stress coefficient based on the actual temperature rise per unit time of the power module;

[0048] Early warning module 5: Issues an early warning when the thermal stress coefficient exceeds the corresponding allowable range;

[0049] Curve Construction Module: Used to construct the time-dynamic response coefficient curve within the latest preset duration;

[0050] Maximum allowable current determination module: When neither warning module three nor warning module five issues a warning, the maximum allowable current of the power module of the current converter is determined based on the curve construction module and the thermal stress coefficient.

[0051] Early warning module 4: Used to issue an early warning when the actual current of the power module exceeds 0.9 times the maximum allowable current of the power module of the current converter.

[0052] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0053] The transformer substation monitoring and protection device is used for analog quantity acquisition, electrical quantity protection, non-electrical quantity protection, remote control, and communication functions on the high and low voltage sides of wind power and photovoltaic power generation transformer substations. It enables the substation to remotely manage and automatically monitor the new energy power plant transformer substations, meeting the "unmanned or minimally staffed" operation and management requirements of the power plant transformer substations.

[0054] By integrating the AC conversion module, CPU module, input / output module, and human-machine interface module, the functional boundaries and signal interaction logic of each module are clearly defined, achieving deep collaboration of data sampling and processing, communication, control, and protection functions. This solves the problems of dispersed modules and poor collaboration in traditional devices, and improves the overall efficiency of measurement, control, and protection in the transformer substation system.

[0055] The optional communication module supports long-distance data transmission, meeting the needs of remote management of all information on the high and low voltage sides of the transformer in wind power and photovoltaic scenarios, reducing reliance on manual on-site inspections; the backup module design provides redundancy for functional expansion, can flexibly adapt to new requirements under complex working conditions, and enhances the device's scenario adaptability.

[0056] The AC conversion module achieves precise conversion of high-voltage signals to low-voltage signals through current converters (TA) and voltage converters (TV), while enhancing the isolation between high and low voltage signals and reducing the risk of signal distortion caused by electromagnetic interference. The power supply module is integrated into the AC conversion module, clearly defining the boundaries between signal conversion and power supply functions, ensuring stable power supply to the CPU module and various circuits, and improving the reliability of data processing and operation.

[0057] The protection functions are comprehensive and highly targeted: the protection sub-modules of the CPU module cover multiple units such as ratio differential protection, differential current instantaneous overcurrent protection, and three-stage time-limit current protection, which comprehensively cover fault types such as phase-to-phase short circuit, single-phase ground fault, and inter-turn short circuit inside the transformer. At the same time, special response mechanisms are designed for special operating conditions such as inrush current, overexcitation, and abnormal TA / TV. Flexible activation and deactivation and blocking logic are realized through soft pressure plates and control words, which greatly improves the safety protection capability of the box-type transformer under complex operating conditions and effectively reduces the risk of fault expansion.

[0058] The human-machine dialogue module enables intuitive operation and interaction between people and the device, making it easier for maintenance personnel to set parameters, view status and handle alarms in real time, thus improving the ease of use and maintenance efficiency of the device. Attached Figure Description

[0059] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0060] Figure 1 This is a schematic diagram of the components of the present invention;

[0061] Figure 2 This is a schematic diagram of the control panel of the present invention;

[0062] Figure 3 This is a schematic diagram of the TV disconnection alarm of the present invention;

[0063] Figure 4 This is a schematic diagram of the TA disconnection alarm of the present invention;

[0064] Figure 5 This is a schematic diagram of the high-pressure FC interlocking principle of the present invention;

[0065] Figure 6 This is a partial menu illustration of the present invention. Detailed Implementation

[0066] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0067] Furthermore, in this invention, the use of terms such as "first" and "second" is for descriptive purposes only and does not specifically refer to any order or sequence, nor is it intended to limit the invention. They are merely used to distinguish components or operations described using the same technical terms and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions and features of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If a combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0068] The present invention provides the following embodiments:

[0069] Example 1: This embodiment of the invention provides a transformer substation monitoring and protection device, such as... Figures 1-6 The diagram shows a chassis, on which a control panel is mounted, and also includes:

[0070] AC converter module, CPU module, output module, input module, human-computer interaction module;

[0071] The AC conversion module is used to convert power signals. The CPU module integrates data sampling and processing, communication and protection functions. The input and output modules are responsible for signal input and output control. The human-machine interface module realizes the operation interaction between people and the device.

[0072] Preferably, the optional communication module is used for long-distance data transmission, and the spare module is used for expanding functions. All modules cooperate through signal interaction to jointly realize the measurement, control and protection of the transformer substation system.

[0073] The AC conversion module includes a current converter (TA) and a voltage converter (TV), which are used to convert the secondary current and voltage signals of the system's TA and TV into weak electrical signals for the CPU module to acquire and process, and also serve as a strong-weak electrical isolation mechanism. The AC conversion module also integrates the device's power supply module.

[0074] Preferably, the CPU module includes a protection submodule, which includes:

[0075] Ratio differential protection unit: used to protect transformers; can detect internal phase-to-phase short circuits, high-voltage side single-phase ground faults and turn-to-layer short circuits; and effectively cope with inrush current, over-excitation operating conditions and abnormal current transformer conditions.

[0076] Differential current instantaneous trip protection unit: It operates instantaneously when the differential current of any phase exceeds the differential current instantaneous trip setting value;

[0077] Differential current over-limit alarm unit: When the differential current of any phase exceeds the differential current over-limit threshold for a duration exceeding the differential current over-limit delay setting, a differential current over-limit alarm message is issued.

[0078] Three-stage time-limited current protection unit: It is equipped with time-limited overcurrent protection in stage I, stage II, and stage III. When the time-limited overcurrent protection in stage I, stage II, and stage III is activated, the TV disconnection detection protection is blocked.

[0079] Overload protection unit: Used for overload fault protection of electrical equipment in the device. When the current of the electrical equipment exceeds the overload setting value, it will output an alarm signal or trigger a trip action according to the setting.

[0080] Zero-sequence current protection unit: When a zero-sequence current is generated and exceeds the set value, it will output an alarm signal or trigger a trip action according to the setting to cut off the fault circuit and ensure the safe operation of the system.

[0081] Low voltage protection unit: Used for voltage anomaly protection in power systems. It is activated when the system voltage is lower than the set value and there is current in any phase or the circuit breaker is closed. It is locked when the TV is disconnected. It is activated and deactivated by a soft pressure plate to ensure the safe and stable operation of the system under low voltage conditions.

[0082] Preferably, the protection submodule further includes:

[0083] Overvoltage protection unit: Used for overvoltage fault protection in power systems. When the system voltage exceeds the set value, the fault circuit is cut off in time by switching on or off the soft pressure plate.

[0084] TV disconnection alarm unit: Detects TV disconnection and issues an alarm signal after a delay;

[0085] TA anomaly detection unit: The instantaneous TA anomaly alarm and lockout function is determined when the differential current is greater than 0.5 times the minimum differential operating current;

[0086] To prevent accidental locking of the current transformer (CT) during transient operations, transient CT anomaly alarms will not be triggered if any of the following conditions are met:

[0087] 1) The maximum phase current on each side is greater than 1.2Ie;

[0088] 2) Before startup, the maximum phase current on this side is less than 0.5 times the differential startup current;

[0089] The current transformer (CT) is considered to be abnormal if the current on either side simultaneously meets the following conditions:

[0090] 1) The open-circuit phase current is less than 0.05A;

[0091] 2) At least one phase current in the three-phase current on this side remains unchanged;

[0092] The control word allows you to select whether to block the ratio differential protection while triggering an instantaneous TA abnormal alarm signal.

[0093] TA disconnection alarm unit: Implements TA disconnection alarm function;

[0094] High-pressure FC re-pressure interlock: Implements the high-pressure FC re-pressure interlock function.

[0095] The reinforced unit enclosure is designed to resist strong vibration and interference, making it particularly suitable for harsh environments. It can be installed in a distributed manner within the switch cabinet for operation.

[0096] The device employs a reinforced unit chassis, designed to withstand strong vibrations and interference, ensuring high reliability even when installed in harsh environments. No additional AC / DC input interference suppression modules are required, regardless of whether it is installed in a panel or distributed configuration. The control panel includes a display screen, signal indicator lights, and an operation keypad.

[0097] The beneficial effects of the above technical solution are as follows: the transformer substation monitoring and protection device is used for analog quantity acquisition, electrical quantity protection, non-electrical quantity protection, remote control, and communication functions on the high and low voltage sides of wind power and photovoltaic power generation transformer substations. It enables the substation to remotely manage and automatically monitor the new energy power plant transformer substations, meeting the "unmanned operation and minimal staffing" operation and management requirements of the power plant transformer substations.

[0098] By integrating the AC conversion module, CPU module, input / output module, and human-machine interface module, the functional boundaries and signal interaction logic of each module are clearly defined, achieving deep collaboration of data sampling and processing, communication, control, and protection functions. This solves the problems of dispersed modules and poor collaboration in traditional devices, and improves the overall efficiency of measurement, control, and protection in the transformer substation system.

[0099] The optional communication module supports long-distance data transmission, meeting the needs of remote management of all information on the high and low voltage sides of the transformer in wind power and photovoltaic scenarios, reducing reliance on manual on-site inspections; the backup module design provides redundancy for functional expansion, can flexibly adapt to new requirements under complex working conditions, and enhances the device's scenario adaptability.

[0100] The AC conversion module achieves precise conversion of high-voltage signals to low-voltage signals through current converters (TA) and voltage converters (TV), while enhancing the isolation between high and low voltage signals and reducing the risk of signal distortion caused by electromagnetic interference. The power supply module is integrated into the AC conversion module, clearly defining the boundaries between signal conversion and power supply functions, ensuring stable power supply to the CPU module and various circuits, and improving the reliability of data processing and operation.

[0101] The protection functions are comprehensive and highly targeted: the protection sub-modules of the CPU module cover multiple units such as ratio differential protection, differential current instantaneous overcurrent protection, and three-stage time-limit current protection, which comprehensively cover fault types such as phase-to-phase short circuit, single-phase ground fault, and inter-turn short circuit inside the transformer. At the same time, special response mechanisms are designed for special operating conditions such as inrush current, overexcitation, and abnormal TA / TV. Flexible activation and deactivation and blocking logic are realized through soft pressure plates and control words, which greatly improves the safety protection capability of the box-type transformer under complex operating conditions and effectively reduces the risk of fault expansion.

[0102] The human-machine dialogue module enables intuitive operation and interaction between people and the device, making it easier for maintenance personnel to set parameters, view status and handle alarms in real time, thus improving the ease of use and maintenance efficiency of the device.

[0103] Example 2, based on Example 1, divides the chassis into several zones, each zone corresponding to an air-cooling device; the transformer substation monitoring and protection device also includes: an air-cooling control device, comprising:

[0104] Temperature Detection Module 1: The surface temperature of the key heating components in each zone is measured by Temperature Detection Module 1;

[0105] Temperature detection module 2: Used to detect the temperature of the air intake area of ​​the air-cooled device;

[0106] Regional detection devices: used to detect ambient wind speed and ambient air pressure within the zone;

[0107] Flow field coupling analysis module: used to determine the wind speed-pressure synchronization coefficient based on ambient air pressure and ambient wind speed, and to determine the flow field dynamics-flow state coupling coefficient based on the wind speed-pressure synchronization coefficient, ambient air pressure, and ambient flow velocity;

[0108] Early warning module 1: Used to issue an early warning when the surface temperature of any key heat-generating device is greater than k (a value of 0.8-0.9) times the corresponding initial heat dissipation trigger temperature, before early warning module 2 issues an early warning.

[0109] Calibration control module: When the early warning module issues an early warning, it controls the air-cooled device to operate at rated output power for the pre-inspection period. Based on the detection results of the detection device within the area during the pre-inspection period, it obtains the initial flow field dynamic-fluid state coupling coefficient determined by the flow field coupling analysis module.

[0110] Heat dissipation analysis module: used to determine the heat dissipation effect coefficient based on the initial flow field dynamic-fluid regime coupling coefficient;

[0111] Temperature adjustment module: used to determine the heat dissipation trigger temperature of key heat-generating components after adjustment based on the initial flow field dynamic-fluid state coupling coefficient when the heat dissipation effect coefficient is less than the corresponding reference value;

[0112] Early warning module 2: It is used to issue an early warning when the surface temperature of any critical heat-generating component exceeds the corresponding adjusted heat dissipation trigger temperature of the critical heat-generating component, and to remind the corresponding air-cooling device to adjust its control parameters or start the air-cooling device (the first time is to start, and subsequent times are to adjust).

[0113] Flow field dynamics-coupling coefficient = ambient wind speed × (air pressure at the outlet of the air-cooling device - ambient air pressure) × "wind speed-air pressure synchronization coefficient" ÷ reference wind speed ÷ reference pressure difference; the reference pressure difference is the reference value corresponding to "air pressure at the outlet of the air-cooling device - ambient air pressure";

[0114] The flow velocity-pressure synchronization coefficient is as follows:

[0115] When "ambient wind speed ÷ reference wind speed" is within the corresponding range (0.9 to 1.1), and "(air pressure at the outlet of the air-cooling device - ambient air pressure) ÷ reference pressure difference" is within the second range (0.9 to 1.1), then the velocity-pressure coordination coefficient is 1.

[0116] When "ambient wind speed ÷ reference wind speed" is not within the first range or "(air pressure at the outlet of the air-cooled device - the ambient air pressure) ÷ reference pressure difference" is within the second range;

[0117] First, identify the abnormal ratios that do not meet the corresponding range requirements ("ambient wind speed ÷ reference wind speed" or "ambient wind speed ÷ reference wind speed"). Then, the velocity-pressure synchronization coefficient is the first value (0.8 to 0.9) that is less than 1.

[0118] When "ambient wind speed ÷ reference wind speed" is not within the first range and "(air pressure at the outlet of the air-cooling device - ambient air pressure) ÷ reference pressure difference" is not within the second range, the velocity-pressure synchronization coefficient is the second value (0.7 to 0.8) of the first value which is less than 1.

[0119] Adjusted heat dissipation trigger temperature of key heat-generating components = initial heat dissipation trigger temperature of key heat-generating components × (1 - heat dissipation effect coefficient × temperature correction coefficient).

[0120] Heat dissipation efficiency coefficient = ;

[0121] Where U is the initial flow field dynamic-fluid regime coupling coefficient; The heat dissipation trigger temperature of the j-th initial critical heat-generating device in the current wind region; This is the current detected value from the temperature detection module; For the j-th wind region of the current time The corresponding baseline value;

[0122] The heat dissipation effect index is the coefficient of flow field dynamics-fluid regime coupling; the heat dissipation effect is evaluated by heat dissipation power.

[0123] Reference wind speed: It is a reference value used to normalize the ambient wind speed in the calculation of flow field dynamics-coupling coefficient. It is usually the design wind speed of the air-cooled device under standard operating conditions (such as rated power and standard ambient air pressure) and is used to quantify the deviation between the actual ambient wind speed and the standard condition.

[0124] Reference pressure difference: refers to the reference value of "air pressure at the outlet of the air-cooled device - ambient air pressure". It is a reference value used to normalize the air pressure difference in the calculation of flow field dynamics and coupling coefficient. It is determined by the design parameters of the air-cooled device (such as the rated air pressure of the fan and the ventilation characteristics of the chassis structure) and is used to quantify the deviation between the actual air pressure difference and the standard state.

[0125] The j-th key heat-generating device in the current wind zone, in " The corresponding baseline value is a reference value used to normalize the temperature difference in the calculation of the heat dissipation effect coefficient. It is determined by the thermal characteristics of the key heat-generating components (such as heat capacity and heat dissipation area) and the heat dissipation capacity of the air-cooling system (such as heat dissipation efficiency under standard wind speed and air pressure). It is used to quantify the deviation between the actual temperature difference and the standard heat dissipation conditions.

[0126] The temperature correction factor (with a value greater than 0 and less than 1) is related to factors such as the heat load of key heat-generating components and the heat dissipation margin of the air-cooling system, and is usually obtained through experimental calibration. Specifically, it varies depending on the dynamic-fluid-state coupling coefficient of the flow field and the temperature difference. "Under operating conditions, test the actual heat dissipation effect of the air-cooled device (such as heat dissipation power and temperature drop rate), and fit the correspondence between the temperature correction coefficient and these operating condition parameters to form a correction coefficient table or correction coefficient function for the system to call."

[0127] The heat dissipation power of the air-cooled device was experimentally tested under different flow field dynamic-fluid regime coupling coefficients. For example, in a laboratory environment, different combinations of ambient wind speed and air pressure difference were simulated to obtain the corresponding flow field dynamic-fluid regime coupling coefficients, and the actual heat dissipation power of the air-cooled device was measured simultaneously. The experimental data were fitted (e.g., power function fitting) to determine... The value of is taken from 0.5 to 1 to accurately reflect the influence of the flow field dynamic-fluid state coupling coefficient on the heat dissipation power, ultimately forming a value corresponding to the flow field dynamic-fluid state coupling coefficient. Value tables or function relationships are embedded in the system's heat dissipation analysis module.

[0128] The beneficial effects of the above technical solution are as follows:

[0129] The chassis is divided into several zones, each corresponding to a separate air-cooling unit. Combined with a temperature sensing module, precise temperature measurement of key heat-generating components (such as the CPU module and AC converter module) in each zone enables "device-level" targeted heat dissipation. For example, for areas containing high-heat-generating components such as the ratio differential protection unit, the power and airflow of the air-cooling unit can be independently adjusted, avoiding the drawbacks of traditional overall air cooling such as "local overheating and global energy consumption," thus improving the thermal stability of key components.

[0130] The flow field coupling analysis module determines the wind speed-pressure synchronization coefficient based on ambient air pressure and wind speed, and then calculates the flow field dynamics-fluid regime coupling coefficient, quantifying and integrating multiple physical field parameters such as "flow field, air pressure, and wind speed". Compared with traditional heat dissipation control that only relies on temperature thresholds, this solution can accurately determine the matching degree between heat dissipation efficiency and flow field under different environments in different chassis, improving the matching accuracy between the heat dissipation power of the air-cooled device and actual needs.

[0131] Early warning module one is activated before early warning module two (the trigger temperature is 0.8-0.9 times the initial heat dissipation trigger temperature) to achieve "early warning and pre-check calibration": before the device temperature reaches severe overheating, the air cooling device is controlled to perform a pre-check at rated power to obtain the initial flow field coupling coefficient and determine the initial environmental air cooling state.

[0132] The trigger temperature is dynamically adjusted. When the heat dissipation effect (combined with the flow field state and temperature difference state) is insufficient (the coefficient is less than the reference value), the trigger temperature threshold is adaptively increased. This ensures the effectiveness of heat dissipation and avoids the air-cooled device from running at full load for a long time, thus reducing the overall energy consumption by more than 10%.

[0133] The system achieves automation and intelligence in air-cooling control through the interconnected modules of "temperature detection, flow field analysis, early warning, calibration, and heat dissipation adjustment." Maintenance personnel do not need to intervene manually; the system can automatically complete the closed-loop control of "temperature monitoring, flow field analysis, and air-cooling parameter adjustment / startup." Simultaneously, early warning information can be remotely transmitted via the communication module, reducing the maintenance response time of transformer substations in wind and solar power scenarios from hours to minutes, significantly lowering the cost of manual inspections and troubleshooting time.

[0134] Example 3, based on Example 2, further includes:

[0135] Operation detection module: used to detect the operating parameters of the air-cooled unit, including: input power and temperature of key components;

[0136] Temperature analysis module: used to determine the temperature coefficient based on the temperature of key components of the air-cooled device;

[0137] Time Analysis Module: Used when the Nth warning from Target Warning Module 2 is greater than or equal to 2; to determine the actual time interval between the current warning and the previous warning from Target Warning Module 2, and to determine the interval matching coefficient corresponding to the Nth warning from Target Warning Module 2;

[0138] Matrix construction module: used to divide the flow field dynamics-fluid state coupling coefficient into multiple first intervals and the temperature coefficient into multiple second intervals. A two-dimensional matrix is ​​constructed with the first interval as rows and the second interval as columns. The intersection of each row and each column in the two-dimensional matrix forms a matrix unit. Each matrix unit is configured with a unique air-cooling control strategy (power re-correction ratio).

[0139] Prediction module: Used to collect historical data of the target air-cooled device whose input power is within the same range as the target air-cooled device before the Nth warning and whose historical time interval matching coefficient is qualified (the time interval matching coefficient can be greater than or equal to 1 and less than or equal to 1.2). This includes the historical time interval matching coefficient before adjustment, the input power of the air-cooled device before adjustment and the heat dissipation effect coefficient. The module determines the target adjustment coefficient and, based on the target adjustment coefficient, determines the preliminary target input power P of the target air-cooled device after the Nth warning.

[0140] ;

[0141] This represents the actual input power of the target's air-cooling device during the Nth warning.

[0142] Target adjustment factor = ; The ratio of the adjusted input power (input power of the air-cooled device) to the input power before adjustment in the b-th historical data selected by the prediction module; The heat dissipation effect coefficient corresponding to the b-th historical data selected for the prediction module; The interval matching coefficient corresponding to the b-th historical data selected by the prediction module; The total amount of historical data selected for the prediction module;

[0143] Air-cooled control analysis module: Based on the target air-cooled control strategy determined by the two-dimensional matrix of the flow field dynamic-fluid state coupling coefficient and steady-state coefficient at the Nth warning, the initial target input power of the target air-cooled device after the Nth warning is corrected, and the target input power of the target air-cooled device after the Nth warning is finally determined.

[0144] The target input power of the target air-cooled device after the Nth warning = P × the correction ratio corresponding to the target air-cooling control strategy (the value is 0.9 to 1.1).

[0145] The temperature coefficient is the maximum value of "actual temperature ÷ maximum allowable temperature" for all critical components;

[0146] Time interval matching coefficient = actual time interval ÷ ideal time interval between two control parameter adjustments of the air-cooled device;

[0147] Target early warning module two is the current early warning module two, and its corresponding air-cooling device is the target air-cooling device;

[0148] In this embodiment, all input power is effective input power;

[0149] In this embodiment, all input power refers to effective input power, which is the power actually used by the air-cooling device to generate effective heat dissipation. Ineffective power caused by equipment losses (such as internal friction of the motor, circuit losses, etc.) must be excluded.

[0150] The flow field dynamics-fluid regime coupling coefficient output by the flow field coupling analysis module is divided into multiple continuous intervals based on "heat dissipation friendliness". For example:

[0151] Range 1 (0-0.3): Excellent flow field (high ambient wind speed, good air pressure matching, and heat dissipation efficiency improved by more than 20%).

[0152] Range 2 (0.3–0.6): Good flow field (heat dissipation efficiency meets design expectations);

[0153] Interval 3 (0.6-0.9): Flow field is average (attention should be paid to the decay of heat dissipation efficiency);

[0154] Range 4 (0.9-1.0): Extremely poor flow field (e.g., blocked air ducts, no wind in the environment, heat dissipation efficiency decreases by more than 30%).

[0155] The temperature coefficient (second interval) is based on the temperature coefficient output by the temperature analysis module (the maximum value of "actual temperature ÷ maximum allowable temperature" for all key components), and is divided into multiple continuous intervals according to "temperature proximity". For example:

[0156] Range A (0~0.5): Excellent temperature performance (critical component temperatures are far below the upper limit, and heat dissipation requirements are extremely low).

[0157] Range B (0.5~0.7): Good temperature condition (temperature is within a safe range, and heat dissipation requirements are moderate).

[0158] Range C (0.7~0.9): Temperature is generally normal (temperature is close to the upper limit, heat dissipation needs to be strengthened).

[0159] Range D (0.9~1.0): Extreme temperature difference (the temperature of critical components is approaching or exceeding the upper limit, and the need for heat dissipation is urgent).

[0160] The ideal time interval refers to the optimal time threshold between two consecutive adjustments of the control parameters of the air-cooling device. Its core is to ensure that the air-cooling control rhythm is neither too frequently adjusted, which would cause waste of resources and wear and tear on the device's lifespan, nor too slowly adjusted, which would cause overheating of key components.

[0161] The beneficial effects of the above technical solution are as follows:

[0162] By collecting core parameters such as input power and key component temperature in real time through the detection module, and combining this with the temperature coefficient determined by the temperature analysis module (the maximum value of "actual temperature of key components ÷ maximum allowable temperature"), the thermal load status of the air-cooling device can be accurately grasped. Furthermore, by using the matrix matching of the flow field dynamics-fluidity coupling coefficient and temperature coefficient in the matrix construction module, a unique air-cooling control strategy can be configured for different flow field heat dissipation friendliness (e.g., heat dissipation efficiency increased by more than 20% in the optimal flow field range, and heat dissipation efficiency decreased by more than 30% in the poor flow field range) and temperature proximity (e.g., the temperature of key components approaches the upper limit in the poor temperature field range). This enables precise allocation of heat dissipation resources, effectively improving overall heat dissipation efficiency and reducing the risk of key components being damaged by overheating.

[0163] The prediction module calculates the target adjustment coefficient based on historical data (valid data with qualified time interval matching coefficients within the same input power range) to obtain the preliminary target input power. Then, the air-cooled control analysis module combines matrix control strategy to make corrections (correction ratio ranges from 0.9 to 1.1). This ensures that the input power adjustment conforms to the patterns of historical effective operating conditions and adapts to the real-time state of the current flow field and temperature, avoiding blind power adjustment and achieving scientific dynamic control of input power. This reduces ineffective power loss while ensuring heat dissipation.

[0164] The time analysis module avoids the problem of excessively frequent or excessively slow adjustments to the control parameters of the air-cooled unit by determining the matching coefficient between the actual time interval and the ideal time interval (time interval matching coefficient = actual time interval ÷ ideal time interval). Excessive adjustments lead to resource waste and shortened unit lifespan, while excessively slow adjustments can cause overheating of critical components. This module ensures that the adjustment rhythm is within the optimal range, reducing equipment damage and additional energy consumption caused by improper operation and maintenance, thereby lowering long-term operation and maintenance costs.

[0165] The precise temperature control, scientific power regulation, and reasonable adjustment time intervals achieved through multi-module collaboration reduce the operating pressure of the air-cooled device from multiple dimensions such as heat load, power load, and mechanical load, slow down the aging rate of key components, effectively extend the overall service life of the equipment, reduce the frequency of equipment replacement or overhaul, and save enterprises the cost of equipment purchase and overhaul.

[0166] The solution achieves fully automated logic across the entire process, from data acquisition and status analysis to strategy matching and power adjustment, through the collaboration of multiple modules, reducing reliance on manual intervention. The prediction module's mining and utilization of historical data demonstrates the intelligent development of data value, enabling the operation and control of the air-cooled unit to possess data-driven intelligent decision-making capabilities, which aligns with the trend of industrial intelligent development.

[0167] The calculation of the temperature coefficient focuses on the worst-case temperature conditions for all critical components (taking the maximum value of "actual temperature ÷ maximum allowable temperature"), ensuring a thorough identification of risks. The interval division of the flow field dynamics-fluid regime coupling coefficient (such as the flow field extreme range focusing on extreme conditions such as duct blockage and no wind) also covers various unfavorable flow field conditions. Multi-dimensional state monitoring and strategy matching enable the air-cooled device to maintain reliable operation under complex conditions, reducing the probability of equipment failure due to heat dissipation failure and improving the stability of system operation.

[0168] Example 4, based on any one of Examples 1-3, includes a current converter detection device, which comprises:

[0169] Power module acquisition module: used to acquire the current and temperature of the power module of the current converter;

[0170] Response Analysis Module: Used to determine the current coefficient and thermal coefficient of the power module based on the current converter and the average value of all key temperature regions, and combine the current coefficient and thermal coefficient to determine the dynamic response coefficient;

[0171] Current coefficient = Actual current of power module ÷ Rated current of power module;

[0172] Thermal coefficient = Actual temperature rise per unit time of power module ÷ Maximum allowable temperature rise per unit time of power module;

[0173] The actual temperature rise per unit time of the power module is determined based on the average value of all critical temperature regions; the actual temperature rise per unit time of the power module is the average temperature rise per unit time of all critical temperature regions of the power module.

[0174] Dynamic response coefficient = Current coefficient ÷ Thermal coefficient;

[0175] Early warning module 3: Used to issue an early warning when the dynamic response coefficient exceeds the corresponding allowable range;

[0176] Temperature analysis module: used to determine the temperature gradient based on the temperature of the key temperature region of the power module and to determine the thermal stress coefficient based on the actual temperature rise per unit time of the power module;

[0177] Hot stress coefficient = (Temperature gradient of critical temperature region of power module ÷ Maximum allowable temperature gradient of critical temperature region of power module) × Hot stress coefficient;

[0178] First, determine the difference between the highest and lowest temperatures within each critical temperature region. Divide this difference by the physical distance between the two temperature points to obtain the temperature gradient for that critical temperature region. Then, take the maximum temperature gradient of all critical temperature regions as the temperature gradient of the power module's critical temperature region. The maximum permissible temperature gradient of the power module's critical temperature region is based on the factory calibration.

[0179] Early warning module 5: Issues an early warning when the thermal stress coefficient exceeds the corresponding allowable range;

[0180] Curve Construction Module: Used to construct the time-dynamic response coefficient curve within the latest preset duration;

[0181] Maximum allowable current determination module: When neither warning module three nor warning module five issues a warning, the maximum allowable current of the power module of the current converter is determined based on the curve construction module and the thermal stress coefficient.

[0182] The maximum allowable current of the power module of the current converter = the rated current of the power module × [1 - (1 - dynamic response coefficient) × current correction coefficient 1 - (thermal stress coefficient) × current correction coefficient 2];

[0183] The preset dynamic response coefficient range is defined as the average slope of the "time-dynamic response coefficient curve" and the current correction coefficient 1, where the current correction coefficient 1 has a value greater than 0 and less than 0.5.

[0184] Early warning module 4: Used to issue an early warning when the actual current of the power module exceeds 0.9 times the maximum allowable current of the power module of the current converter.

[0185] Correction factor one and correction factor two can be determined in the following manner:

[0186] Current correction factor one:

[0187] The dynamic response coefficient is used to quantify the correction effect of its time trend on the maximum allowable current. The dynamic response coefficient reflects the coordinated response characteristics of the power module in terms of "current-thermal state". If its trend over time (average slope of the curve) is abnormal, the maximum allowable current needs to be adjusted using this coefficient to avoid module overload.

[0188] How to obtain:

[0189] Determined through the preset correspondence of "Dynamic Response Coefficient Range -":

[0190] First, divide the dynamic response coefficient range (e.g., normal range, slightly abnormal range, severely abnormal range);

[0191] For each interval, the average slope of the "time-dynamic response coefficient curve" is calculated (the slope reflects the rate of change of the coefficient over time).

[0192] A mapping table between "interval-slope" and current correction factor 1 is pre-established, for example:

[0193] If the dynamic response coefficient is within the normal range and the average slope of the curve is ≤0.01 / minute, then the current correction factor is set to 0.2.

[0194] For the slight abnormality range of the dynamic response coefficient and the average slope of the curve ∈ (0.01, 0.03] / min, the current correction coefficient is set to 0.3.

[0195] Similarly, the mapping relationship is determined based on the actual test data.

[0196] Value range: The default is greater than 0 and less than 0.5, for example, a value between 0.1 and 0.4. The specific value is determined by the degree of correlation between the above "interval-slope" (the stronger the correlation, the larger the correction coefficient, and the more obvious the reduction of the maximum allowable current).

[0197] Current correction factor two:

[0198] This coefficient is used to quantify the correction effect of the hot-state stress coefficient on the maximum allowable current. The hot-state stress coefficient reflects the combined stress level of the power module's temperature gradient and hot-state response. The higher the stress, the more necessary it is to use this coefficient to further limit the maximum allowable current to prevent module failure caused by thermal stress.

[0199] How to obtain:

[0200] Determined through the pre-defined correspondence of the "hot stress coefficient range":

[0201] Divide the thermal stress coefficient range (e.g., low stress range, medium stress range, high stress range);

[0202] For each interval, a corresponding current correction factor of 2 is pre-calibrated, for example:

[0203] Hot stress coefficient ≤ 0.8 (low stress) → Current correction factor 2 is set to 0.1;

[0204] The thermal stress coefficient ∈ (0.8, 1.2] (medium stress) → the current correction factor is set to 0.2;

[0205] Hot stress coefficient > 1.2 (high stress) → Current correction factor 2 is set to 0.3;

[0206] (Specific ranges and coefficients need to be calibrated through thermal stress testing and life tests.)

[0207] Value range: Usually preset to greater than 0 and less than 0.5 (consistent with the logic of correction factor one, ensuring that the reduction of the maximum allowable current is within a reasonable range), for example, a value between 0.1 and 0.4, specifically determined by the severity of thermal stress.

[0208] The mapping table for the current correction factor 1 needs to be calibrated through power module thermal stress cycle experiments;

[0209] The mapping table for current correction factor 2 needs to be calibrated through power module lifetime acceleration experiments;

[0210] Critical temperature areas refer to the typical areas in the power module where thermal stress is most concentrated, including the IGBT chip area (chip center and edge), the package housing area (near the chip side and far from the chip side), and the wire bonding area (bonding points and adjacent pins), which are the core monitoring areas for thermal analysis.

[0211] Maximum permissible temperature rise per unit time: calibrated by the power module's factory thermal characteristic test or industry standards (such as IEC 60747-9), reflecting the maximum permissible rate of temperature rise of the module within its safe lifespan.

[0212] The beneficial effects of the above technical solution are as follows:

[0213] Electric-thermal synergistic monitoring: By combining the current coefficient and thermal coefficient to form a dynamic response coefficient, and introducing the temperature gradient to quantify the thermal stress coefficient, the power module status is comprehensively characterized from two dimensions: current response characteristics and thermal stress distribution. This avoids the one-sidedness of monitoring a single parameter and can accurately identify complex fault scenarios such as "current overload but abnormal thermal response" and "thermal stress concentration but normal current".

[0214] The graded early warning mechanism consists of three levels: early warning module 3 (dynamic response coefficient early warning), early warning module 5 (thermal stress coefficient early warning), and early warning module 4 (current over-limit early warning). These three levels can be linked together to trigger early warnings in the early stage of module performance degradation (coefficient abnormality stage), the thermal stress critical stage, and the current overload stage, thus providing sufficient time for fault handling.

[0215] Curve-based trend correction: The time-dynamic response coefficient curve generated by the curve building module can reflect the trend of module performance changes over time (such as the decay of response characteristics due to aging). Combined with the current correction coefficient, the maximum allowable current is adjusted in a trend-based manner, which avoids premature current limitation due to module aging and prevents overload caused by ignoring the trend.

[0216] Thermal stress synergistic correction: The thermal stress coefficient combines the temperature gradient with the thermal response, and further adjusts the maximum allowable current through the current correction coefficient 2 to ensure that the module automatically derating in high thermal stress scenarios, reducing the impact of thermal fatigue on the module life; while in low thermal stress scenarios, it can fully release power and improve the module utilization rate.

[0217] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A transformer substation monitoring and protection device, comprising a chassis, wherein a control panel is provided on the chassis, characterized in that: Also includes: AC converter module, CPU module, output module, input module, human-computer interaction module; The AC conversion module is used to convert power signals, the CPU module integrates data sampling and processing, communication and protection functions, the input and output modules are responsible for signal input and output control, and the human-machine interface module realizes the operation interaction between humans and the device. The chassis is divided into several partitions, each corresponding to an air-cooling unit; The transformer substation monitoring and protection device also includes: air-cooled control device: including: Temperature Detection Module 1: The surface temperature of the key heating components in each zone is measured by Temperature Detection Module 1; Temperature detection module 2: Used to detect the temperature of the air intake area of ​​the air-cooled device; Regional detection devices: used to detect ambient wind speed and ambient air pressure within the zone; Flow field coupling analysis module: used to determine the wind speed-pressure synchronization coefficient based on ambient air pressure and ambient wind speed, and to determine the flow field dynamics-flow state coupling coefficient based on the wind speed-pressure synchronization coefficient, ambient air pressure, and ambient flow velocity; Early warning module 1: Used to issue an early warning when the surface temperature of any critical heat-generating device is greater than k times the corresponding initial heat dissipation trigger temperature, before early warning module 2 issues an early warning. Calibration control module: When the early warning module issues an early warning, it controls the air-cooled device to operate at rated output power for the pre-inspection period. Based on the detection results of the detection device within the area during the pre-inspection period, it obtains the initial flow field dynamic-fluid state coupling coefficient determined by the flow field coupling analysis module. Heat dissipation analysis module: used to determine the heat dissipation effect coefficient based on the initial flow field dynamic-fluid regime coupling coefficient; Temperature adjustment module: used to determine the heat dissipation trigger temperature of key heat-generating components after adjustment based on the initial flow field dynamic-fluid state coupling coefficient when the heat dissipation effect coefficient is less than the corresponding reference value; Early warning module 2: It is used to issue an early warning when the surface temperature of any key heat-generating component exceeds the corresponding adjusted heat dissipation trigger temperature of the key heat-generating component, and to remind the corresponding air-cooling device to adjust the control parameters or start the air-cooling device.

2. The transformer substation monitoring and protection device according to claim 1, characterized in that: It also includes: a communication module for long-distance data transmission, a backup module for expanding functions, and all modules cooperate through signal interaction to jointly realize the measurement, control and protection of the transformer substation system; The AC conversion module includes a current converter (TA) and a voltage converter (TV), which are used to convert the secondary current and voltage signals of the system's TA and TV into weak electrical signals for the CPU module to acquire and process, and also serve as a strong-weak electrical isolation mechanism; the AC conversion module also integrates the device's power supply module.

3. The transformer substation monitoring and protection device according to claim 1, characterized in that: The CPU module includes a protection submodule, which includes: Ratio differential protection unit: used to protect transformers; can detect internal phase-to-phase short circuits, high-voltage side single-phase ground faults and turn-to-layer short circuits; and effectively cope with inrush current, over-excitation operating conditions and abnormal current transformer conditions. Differential current instantaneous trip protection unit: It operates instantaneously when the differential current of any phase exceeds the differential current instantaneous trip setting value; Differential current over-limit alarm unit: When the differential current of any phase exceeds the differential current over-limit threshold for a duration exceeding the differential current over-limit delay setting, a differential current over-limit alarm message is issued. Three-stage time-limited current protection unit: It is equipped with time-limited overcurrent protection in stage I, stage II, and stage III. When the time-limited overcurrent protection in stage I, stage II, and stage III is activated, the TV disconnection detection protection is blocked. TA anomaly detection unit: The instantaneous TA anomaly alarm and lockout function is determined when the differential current exceeds 0.5 times the minimum differential operating current; to prevent false lockout of TA during instantaneous operation, instantaneous TA anomaly alarm determination will not be performed if any of the following conditions are met: 1) The maximum phase current on each side is greater than 1.2Ie; 2) Before startup, the maximum phase current on this side is less than 0.5 times the differential startup current; The current transformer (CT) is considered to be abnormal if the current on either side simultaneously meets the following conditions: 1) The phase current of the disconnected circuit is less than 0.05A; 2) At least one phase current in the three-phase current on this side remains unchanged; The control word allows you to select whether to block the ratio differential protection while simultaneously triggering an instantaneous TA abnormal alarm signal.

4. The transformer substation monitoring and protection device according to claim 3, characterized in that: The protection submodule also includes: an overload protection unit, a zero-sequence current protection unit, an undervoltage protection unit, an overvoltage protection unit, a TV disconnection alarm unit, a TA disconnection alarm unit, and a high-voltage FC overvoltage interlock.

5. The transformer substation monitoring and protection device according to claim 1, characterized in that: The device's input power supply is AC / DC compatible, as is its auxiliary power supply. The maximum input voltage reaches 600V. The device's switch input circuit power supply is AC / DC compatible, making it suitable for systems with or without DC power supply.

6. The transformer substation monitoring and protection device according to claim 1, characterized in that: Also includes: Operation detection module: used to detect the operating parameters of the air-cooled unit, including: input power and temperature of key components; Temperature analysis module: used to determine the temperature coefficient based on the temperature of key components of the air-cooled device; Time Analysis Module: Used when the Nth warning from Target Warning Module 2 is greater than or equal to 2; to determine the actual time interval between the current warning and the previous warning from Target Warning Module 2, and to determine the interval matching coefficient corresponding to the Nth warning from Target Warning Module 2; Matrix construction module: used to divide the flow field dynamics-fluid state coupling coefficient into multiple first intervals and the temperature coefficient into multiple second intervals. A two-dimensional matrix is ​​constructed with the first interval as rows and the second interval as columns. The intersection of each row and each column in the two-dimensional matrix forms a matrix unit. Each matrix unit is configured with a unique air-cooling control strategy. Prediction module: used to collect historical data that is within the same input power range as the target air-cooled device before the Nth warning and whose historical time interval matching coefficient is qualified after historical adjustment: including the historical time interval matching coefficient before historical adjustment, the input power of the air-cooled device before historical adjustment and the heat dissipation effect coefficient, to determine the target adjustment coefficient, and to determine the preliminary target input power of the target air-cooled device after the Nth warning based on the target adjustment coefficient; Air-cooled control analysis module: Used to adjust the control strategy corresponding to the heat dissipation risk level output by the matrix construction module, correct the initial target input power of the target air-cooled device after the Nth warning, and finally determine the target input power of the target air-cooled device after the Nth warning.

7. The transformer substation monitoring and protection device according to claim 2, characterized in that: Includes a current converter detection device, which includes: Power module acquisition module: used to acquire the current and temperature of the power module of the current converter; Response Analysis Module: Used to determine the current coefficient and thermal coefficient of the power module based on the current converter and the average value of all key temperature regions, and combine the current coefficient and thermal coefficient to determine the dynamic response coefficient; Early warning module 3: Used to issue an early warning when the dynamic response coefficient exceeds the corresponding allowable range; Temperature analysis module: used to determine the temperature gradient based on the temperature of the key temperature region of the power module and to determine the thermal stress coefficient based on the actual temperature rise per unit time of the power module; Early warning module 5: Issues an early warning when the thermal stress coefficient exceeds the corresponding allowable range; Curve Construction Module: Used to construct the time-dynamic response coefficient curve within the latest preset duration; Maximum allowable current determination module: When neither warning module three nor warning module five issues a warning, the maximum allowable current of the power module of the current converter is determined based on the curve construction module and the thermal stress coefficient. Early warning module 4: Used to issue an early warning when the actual current of the power module exceeds 0.9 times the maximum allowable current of the power module of the current converter.

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