Efficient and energy-saving power transformer and cooling system thereof

Abstract

The invention discloses an efficient and energy-saving power transformer and a cooling system thereof, and relates to the technical field of power transformers. Comprising a plurality of temperature sensors which are arranged in different heating areas in the power transformer and configured to acquire thermal state data of key parts of the power transformer in real time, and the key parts comprise a winding, an iron core and insulating oil; and the load monitoring unit is electrically connected to a main loop of the power transformer. According to the invention, temperature sensors are arranged in different heating areas in the power transformer and are combined with a load monitoring unit, so that thermal state data of a winding, an iron core and insulating oil and load data such as operation current and voltage are obtained in real time, and an intelligent control unit establishes a multi-area real-time thermal model based on the data; and a dynamic cooling strategy is generated with the purposes of minimizing cooling energy consumption and ensuring cooling uniformity, and operation parameters of a variable frequency oil pump and a cooling fan in the cooling execution unit are adjusted in a self-adaptive mode.

Description

Technical Field

[0001] This invention relates to the field of power transformer technology, specifically to a high-efficiency and energy-saving power transformer and its cooling system. Background Technology

[0002] As a core component of power transmission and distribution systems, the stable and efficient operation of power transformers is crucial for grid security and energy utilization. Transformers inevitably incur losses during energy conversion, most of which are dissipated as heat. If these losses are not effectively dissipated, the temperature of the windings and core will rise, accelerating the aging of insulation materials, shortening equipment lifespan, and even causing malfunctions. Traditional power transformer cooling systems, such as natural cooling, air cooling, or oil circulation cooling, while meeting basic heat dissipation requirements, face challenges in achieving higher energy efficiency. These include high energy consumption, limited cooling efficiency, poor heat dissipation uniformity, and slow response to changes in transformer load. These factors collectively restrict further improvements in the overall energy efficiency of power transformers.

[0003] Achieving high efficiency and energy saving in power transformers, particularly through the innovative optimization of their cooling systems, is a significant trend in current technological development. While existing cooling technologies address transformer heat dissipation issues, they also face several challenges. For example, to improve heat dissipation efficiency, some cooling systems increase the power of fans or oil pumps, which undoubtedly increases the system's own energy consumption, significantly reducing the overall energy-saving effect of the transformer. Simultaneously, the noise, size, and environmental impact of the cooling system are also issues that cannot be ignored. Existing systems often lack the ability to monitor and intelligently control internal hotspots within the transformer, making it difficult to dynamically adjust cooling strategies according to different operating conditions and load changes. This leads to wasted cooling resources or the risk of localized overheating, failing to truly achieve refined and adaptive cooling management. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a high-efficiency and energy-saving power transformer and its cooling system, solving the problems of high energy consumption, limited cooling efficiency, uneven heat dissipation, and untimely response to load changes in existing cooling systems.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a high-efficiency and energy-saving power transformer cooling system, comprising: Multiple temperature sensors are arranged in different heat-generating areas inside the power transformer to acquire real-time thermal status data of key parts of the power transformer, including windings, core and insulating oil. The load monitoring unit is electrically connected to the main circuit of the power transformer and is configured to acquire load data of the power transformer in real time, including operating current, operating voltage and active power. The cooling unit includes at least one oil circulation pump, at least one cooling fan, and at least one oil-air heat exchanger. The cooling unit is configured to transfer the heat generated inside the power transformer to the external environment through forced oil circulation and air cooling. The intelligent control unit is electrically connected to multiple temperature sensors, a load monitoring unit, and a cooling execution unit. The intelligent control unit is configured for: It receives and processes thermal status data acquired by multiple temperature sensors and load data acquired by a load monitoring unit; Based on the processed thermal state data and load data, combined with preset operating parameters and optimization objectives, a dynamic cooling strategy is generated to maintain the power transformer within the safe operating temperature range. The optimization objectives include minimizing the energy consumption of the cooling system itself and ensuring cooling uniformity. Based on the dynamic cooling strategy, precise control commands are sent to the cooling execution unit to adaptively adjust the operating frequency of the oil circulation pump, the speed of the cooling fan, and the heat dissipation capacity of the oil-air heat exchanger.

[0006] Furthermore, the plurality of temperature sensors include: at least one winding-embedded fiber optic temperature sensor, which is embedded inside the heat dissipation channel of the power transformer winding for monitoring the hot spot temperature of the winding and is resistant to electromagnetic interference; and at least one resistance temperature sensor, which is arranged in the insulating oil for monitoring the average temperature of the insulating oil.

[0007] Furthermore, the load monitoring unit is also configured to: collect the current, voltage and active power signals of the power transformer in real time; and calculate the equivalent load rate based on the signals. The equivalent load rate is used to predict the temperature rise trend and dynamic heat dissipation requirements of the power transformer under different operating conditions.

[0008] Furthermore, the cooling execution unit also includes: at least one variable frequency oil pump for regulating the flow rate of cooling oil; and at least one DC brushless fan for regulating air volume and air speed; the cooling execution unit is heat exchange coupled to the power transformer body through an internal oil circuit system and an external air duct system.

[0009] Furthermore, the intelligent control unit is further configured to: establish a multi-region real-time thermal model of the power transformer, the thermal model being dynamically updated based on thermal state data, load data, and environmental parameters; the intelligent control unit is also configured to assess the thermal aging status and current health indicators of the power transformer insulation system based on the output of the real-time thermal model.

[0010] Furthermore, the dynamic cooling strategy further includes: optimizing the operating parameters of the oil circulation pump and the cooling fan during light load or low temperature operation to reduce the energy consumption of the cooling system itself; and dynamically improving the operating efficiency of the pump and the fan during heavy load or high temperature operation to quickly meet the heat dissipation requirements.

[0011] Furthermore, the cooling execution unit also includes: multiple independently controlled local cooling modules, which are arranged in specific hot spot areas of the power transformer. Each local cooling module is equipped with an independent micro fan or micro radiator for precise and rapid cooling of local hot spots.

[0012] Furthermore, the cooling system also includes a communication module, which is configured to upload thermal status data and cooling system operating status data to the monitoring platform in real time via an industrial-grade network interface or a wireless communication network, and to receive remote control and optimization commands.

[0013] Furthermore, the intelligent control unit also includes: a data storage device for long-term storage of historical operating data, cooling strategy adjustment records, and fault diagnosis information; and an analysis and optimization module configured to perform in-depth analysis of historical data to continuously optimize the parameters of the dynamic cooling strategy.

[0014] The present invention also provides a high-efficiency and energy-saving power transformer, including the high-efficiency and energy-saving power transformer cooling system described in any of the above claims.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention utilizes temperature sensors placed in different heat-generating areas within a power transformer, combined with a load monitoring unit, to acquire real-time thermal state data of the windings, core, and insulating oil, as well as load data such as operating current and voltage. Based on this data, the intelligent control unit establishes a multi-region real-time thermal model, generating a dynamic cooling strategy with the goal of minimizing cooling energy consumption and ensuring cooling uniformity. This strategy adaptively adjusts the operating parameters of the variable frequency oil pump and cooling fan in the cooling execution unit. Furthermore, it employs independent local cooling modules to precisely cool hot spots, effectively solving the problems of high energy consumption, limited cooling efficiency, uneven heat dissipation, and untimely response to load changes inherent in traditional cooling systems. Simultaneously, the intelligent control unit can assess the thermal aging condition of the insulation system, and the communication module enables data upload and remote control. This not only reduces the energy consumption of the cooling system itself and improves the overall energy efficiency of the transformer, but also extends equipment life, facilitates operation and maintenance, and ensures the long-term stable operation of the transformer. Attached Figure Description

[0016] Figure 1 This is a diagram showing the overall system workflow and component interactions of the present invention. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Please see Figure 1 This invention provides a high-efficiency and energy-saving power transformer cooling system, comprising: Multiple temperature sensors are arranged in different heat-generating areas inside the power transformer to acquire real-time thermal status data of key parts of the power transformer, including windings, core and insulating oil. The load monitoring unit is electrically connected to the main circuit of the power transformer and is configured to acquire load data of the power transformer in real time, including operating current, operating voltage and active power. The cooling unit includes at least one oil circulation pump, at least one cooling fan, and at least one oil-air heat exchanger. The cooling unit is configured to transfer the heat generated inside the power transformer to the external environment through forced oil circulation and air cooling. The intelligent control unit is electrically connected to multiple temperature sensors, a load monitoring unit, and a cooling execution unit. The intelligent control unit is configured for: It receives and processes thermal status data acquired by multiple temperature sensors and load data acquired by a load monitoring unit; Based on the processed thermal state data and load data, combined with preset operating parameters and optimization objectives, a dynamic cooling strategy is generated to maintain the power transformer within the safe operating temperature range. The optimization objectives include minimizing the energy consumption of the cooling system itself and ensuring cooling uniformity. Based on the dynamic cooling strategy, precise control commands are sent to the cooling execution unit to adaptively adjust the operating frequency of the oil circulation pump, the speed of the cooling fan, and the heat dissipation capacity of the oil-air heat exchanger.

[0019] Specifically, in the practical application of this cooling system, multiple temperature sensors are first deployed to address the different heat dissipation characteristics inside the power transformer. These sensors must cover the conductor gaps and heat dissipation channels in the windings, the magnetically concentrated areas of the core, and the upper, lower, and middle parts of the insulating oil tank. This ensures real-time acquisition of thermal status data for the three key components: windings, core, and insulating oil, avoiding the omission of local hot spots due to monitoring blind spots in traditional cooling systems. The load monitoring unit employs a high-precision acquisition module, electrically connected to the high-voltage and low-voltage main circuits of the power transformer, capturing real-time operating current, operating voltage, and active power data to provide accurate load data for subsequent analysis.

[0020] The cooling unit uses a variable frequency oil circulation pump, a DC brushless cooling fan, and a high-efficiency finned oil-air heat exchanger. It works in conjunction with forced oil circulation and air cooling: the insulating oil is driven by the variable frequency oil pump and flows through the internal oil circuit system to absorb heat from the windings, iron core and other heat-generating parts. Then it enters the oil-air heat exchanger, where the DC brushless fan blows air to transfer heat to the external environment. Compared with traditional natural cooling or single air cooling, the heat exchange efficiency is significantly improved.

[0021] The intelligent control unit uses an industrial-grade PLC as its core. After receiving and processing data transmitted from temperature sensors and load monitoring units, it combines this data with preset safe operating temperature ranges for the transformer, such as winding hot spot temperature not exceeding 105℃ and average insulating oil temperature not exceeding 85℃. It then generates a dynamic cooling strategy with the optimization goal of "minimizing the cooling system's own energy consumption and ensuring cooling uniformity." For example, when the transformer is detected to be under light load with a load rate below 30% and the ambient temperature is low, the operating frequency of the variable frequency oil pump and the speed of the DC brushless fan are automatically reduced to decrease unnecessary energy consumption. When the load suddenly increases and the load rate exceeds 80% or the local temperature approaches the safe threshold, the oil pump frequency and fan speed are rapidly increased, while simultaneously optimizing the heat dissipation airflow distribution of the oil-air heat exchanger to ensure rapid heat removal. This implementation effectively solves the problems of high energy consumption, slow response, and uneven heat dissipation in traditional cooling systems, keeping the transformer within a safe temperature range for extended periods while reducing the cooling system's own energy consumption and improving overall energy efficiency.

[0022] In this embodiment, the multiple temperature sensors of the power transformer include: at least one winding-embedded fiber optic temperature sensor, which is embedded in the heat dissipation channel of the power transformer winding to monitor the hot spot temperature of the winding and is resistant to electromagnetic interference; and at least one resistance temperature sensor, which is arranged in the insulating oil to monitor the average temperature of the insulating oil.

[0023] Specifically, the winding-embedded fiber optic temperature sensor uses high-temperature resistant quartz fiber, directly embedded in the conductor gaps or pre-designed heat dissipation channels of the winding. Its anti-electromagnetic interference characteristics avoid interference from the transformer's strong electromagnetic environment on the monitoring data, accurately capturing the temperature of local hot spots in the winding, such as at winding conductor joints or weak points in inter-turn insulation, thus solving the problem of hot spot monitoring deviation caused by electromagnetic interference in traditional metal sensors. The resistance temperature detector (RTD) sensor uses a high-precision platinum resistance sensor, respectively arranged in the upper, middle, and lower parts of the insulating oil tank, with the upper part closer to the oil surface and the lower part closer to the bottom of the tank. By collecting data from multiple points, the average temperature of the insulating oil is calculated, avoiding the limitation that a single measuring point cannot reflect the overall oil temperature. The two sensors work together to provide comprehensive and accurate thermal state data for the intelligent control unit, ensuring a reliable basis for subsequent cooling strategy adjustments and effectively preventing the risk of equipment overheating due to missed hot spot detection or misjudgment of oil temperature.

[0024] In this embodiment, the power transformer load monitoring unit is also configured to: collect the current, voltage and active power signals of the power transformer in real time; and calculate the equivalent load rate based on the signals. The equivalent load rate is used to predict the temperature rise trend and dynamic heat dissipation requirements of the power transformer under different operating conditions.

[0025] Specifically, the load monitoring unit, based on real-time acquisition of the power transformer's operating current, operating voltage, and active power signals, introduces an equivalent load factor calculation algorithm. This algorithm enables the prediction of the transformer's temperature rise trend. The formula for calculating the equivalent load factor is as follows: ; The parameters in the formula are defined as follows: Equivalent load factor, dimensionless, reflects the current actual load level of the transformer and its future temperature rise potential; Real-time collected active power of power transformers, in kW; Rated active power of a power transformer, in kW; Current fluctuation coefficient, dimensionless, is calculated as the ratio of real-time operating current to rated current. ,in This is the real-time operating current, in amperes (A). Rated current, in amperes (A); Voltage fluctuation coefficient, dimensionless, is calculated as the ratio of real-time operating voltage to rated voltage. ,in This is the real-time operating voltage, in volts (V). Rated voltage, unit: V; , Weighting coefficients, dimensionless, satisfying Its value is determined by fitting historical data using the least squares method.

[0026] In practical applications, the load monitoring unit collects current, voltage, and active power signals every 10 seconds, substitutes them into a formula to calculate the real-time equivalent load rate, and predicts future temperature rise based on the equivalent load rate change trend over the past hour. For example, if five consecutive calculated values ​​show an upward trend with a single increase exceeding 5%, it is determined that the temperature rise will accelerate within the next 30 minutes. For instance, if a sudden increase in current and voltage is detected, causing the equivalent load rate to rise rapidly from 50% to 75%, the system can predict that the transformer temperature rise will accelerate and send an early warning signal to the intelligent control unit, prompting the cooling strategy to be adjusted in advance. This implementation method solves the problem of traditional cooling systems relying solely on temperature feedback and experiencing response lag, achieving "predictive" control of heat dissipation demand, reducing temporary overheating caused by sudden load increases, and improving equipment operational stability.

[0027] In this embodiment, the power transformer cooling execution unit further includes: at least one variable frequency oil pump for regulating the flow rate of cooling oil; and at least one DC brushless fan for regulating air volume and air speed; the cooling execution unit is heat exchange coupled to the power transformer body through an internal oil circuit system and an external air duct system.

[0028] Specifically, the variable frequency oil pump in the cooling actuator is linked with the intelligent control unit to adjust the cooling oil flow rate based on real-time load and temperature data: under light load, the pump speed is reduced to decrease the amount of cooling oil circulating and avoid energy waste; under heavy load, the speed is increased to increase the flow rate and accelerate heat removal, resulting in significantly lower energy consumption compared to a fixed frequency oil pump. The DC brushless fan uses pulse width modulation technology to adjust airflow and speed, resulting in lower noise levels than traditional AC fans. It can also precisely match the airflow based on the real-time temperature of the oil-air heat exchanger, avoiding excessive or insufficient airflow. The internal oil circuit system is designed with multiple branch loops to ensure that the cooling oil flows evenly through all heat-generating areas of the windings and core. The external air duct system is adapted to the fin structure of the oil-air heat exchanger, optimizing the airflow path and improving heat exchange efficiency. Through the coupled design of the internal oil circuit and external air duct, the cooling actuator can achieve efficient heat transfer while meeting energy-saving and low-noise requirements, solving the problems of high energy consumption, high noise, and uneven heat dissipation in traditional cooling actuators.

[0029] In this embodiment, the intelligent control unit of the power transformer is further configured to: establish a multi-region real-time thermal model of the power transformer, the thermal model being dynamically updated based on thermal state data, load data, and environmental parameters; the intelligent control unit is also configured to evaluate the thermal aging status and current health indicators of the power transformer insulation system based on the output of the real-time thermal model.

[0030] Specifically, the intelligent control unit establishes a real-time thermal model of the power transformer in multiple regions based on the finite element analysis method. The transformer is divided into three independent but related thermal regions: the winding region, the core region, and the insulating oil region. The thermal model parameters of each region, such as thermal conductivity and heat dissipation coefficient, are dynamically updated in combination with real-time thermal state data, i.e., temperature of each region, load data, i.e., equivalent load rate, and environmental parameters, i.e., ambient temperature and humidity. For example, when the ambient temperature rises, the heat dissipation coefficient of each region is adjusted in real time to ensure that the model is consistent with the actual operating state.

[0031] Based on this thermal model, the intelligent control unit further evaluates the thermal aging status of the insulation system and uses a thermal aging accumulation algorithm to calculate the current health index of the insulation system, as shown in the following formula: ; The parameters in the formula are defined as follows: : Insulation system health index, dimensionless, with a value range of 0 to 1. The closer the value is to 1, the better the health status. When it is below 0.6, an early warning is triggered. The number of times the temperature exceeds the threshold within a statistical period, dimensionless, with the statistical period being, for example, one month; : No. The duration during which the temperature of hotspots exceeded the safety threshold during this monitoring, in hours; : No. The winding hot spot temperature during this monitoring is expressed in °C. Temperature effect coefficient, dimensionless, reflects the accelerating effect of different hot spot temperatures on insulation aging. It is simplified based on the Arrhenius thermal aging theory, and the formula is as follows: ,in: The activation energy of insulating materials, such as high-temperature resistant insulating paper, is expressed in J / mol and ranges from 180,000 to 220,000 J / mol. It is determined experimentally based on the specific type of insulating material. : Ideal gas constant, with units of J / (mol·K), and a value of 8.314 J / (mol·K); Convert Celsius to Kelvin (K) to ensure that the temperature unit matches the activation energy and gas constant; : The cumulative operating time of the power transformer since it was put into operation, in hours.

[0032] In practical applications, the intelligent control unit calculates health indicators every 30 minutes: first, it extracts hotspot temperature data within the statistical period, filters out time periods exceeding a safety threshold, such as 105℃, and then calculates the health indicators for each time period. and Then, the values ​​are substituted into the health indicator formula. When the health indicator falls below 0.6, the system automatically issues a warning, reminding maintenance personnel to check the insulation system status. This implementation method shifts maintenance from reactive fault repair to proactive health management, extending the lifespan of the transformer insulation system and reducing the probability of sudden failures.

[0033] In this embodiment, the dynamic cooling strategy for the power transformer further includes: optimizing the operating parameters of the oil circulation pump and the cooling fan during light load or low temperature operation to reduce the energy consumption of the cooling system itself; and dynamically improving the operating efficiency of the pump and fan during heavy load or high temperature operation to quickly meet the heat dissipation requirements.

[0034] Specifically, the dynamic cooling strategy employs differentiated control for different operating conditions: In light-load or low-temperature operating scenarios, such as nighttime load rates below 20% and ambient temperatures below 20°C, the intelligent control unit optimizes the oil circulation pump's operating frequency to 40%-60% of its rated frequency, while simultaneously reducing the cooling fan speed to 30%-50% of its rated speed, minimizing the cooling system's own energy consumption while meeting basic heat dissipation requirements; In heavy-load or high-temperature operating scenarios, such as peak electricity load rates above 90% and ambient temperatures above 35°C, the system rapidly increases the oil circulation pump frequency to 80%-100% of its rated frequency and the cooling fan speed to 80%-100% of its rated speed, while simultaneously optimizing the airflow distribution of the oil-air heat exchanger, prioritizing the cooling of areas with higher temperatures; In medium-load and normal-temperature scenarios, a "step-by-step adjustment" mode is adopted, gradually adjusting parameters based on minor changes in temperature and load to avoid energy consumption fluctuations caused by frequent start-stop cycles.

[0035] In this embodiment, the power transformer cooling execution unit further includes: multiple independently controlled local cooling modules, which are arranged in specific hot spot areas of the power transformer. Each local cooling module is equipped with an independent micro fan or micro radiator for precise and rapid cooling of local hot spots.

[0036] Specifically, the local cooling modules of the cooling execution unit are strategically placed in areas of the transformer prone to localized hot spots, such as the winding ends, core corners, and oil tank outlets. The winding ends have dense wires and limited heat dissipation space, the core corners have dense magnetic fields and concentrated heat generation, and the oil tank outlets have high oil temperatures. Each local cooling module integrates a miniature low-power fan and a high-efficiency heat sink. The miniature fan uses piezoelectric drive technology, consuming only 1 / 5 the energy of traditional fans, and the heat sink uses an aluminum microchannel structure with high thermal conductivity. When the intelligent control unit detects that the temperature of a hot spot in a certain area is more than 5°C higher than the surrounding area through the thermal model, it activates the local cooling module for that area separately: the miniature fan accelerates airflow around the heat sink, quickly dissipating heat from the hot spot without needing to activate the high-power mode of the overall cooling system.

[0037] In this embodiment, the power transformer cooling system also includes a communication module, which is configured to upload thermal status data and cooling system operating status data to the monitoring platform in real time through an industrial-grade network interface or a wireless communication network, and receive remote control and optimization instructions.

[0038] Specifically, the cooling system's communication module adopts an industrial-grade wired + wireless dual-backup design: wired communication connects to the substation's monitoring platform via an RJ45 Ethernet interface, ensuring stable transmission speed and strong anti-interference capabilities; wireless communication uses a 4G / 5G industrial module, automatically switching in case of wired network failure to ensure uninterrupted data transmission. The communication module uploads real-time data including thermal status data and cooling system operating status data. Thermal status data covers the temperature of each zone and oil temperature, while cooling system operating status data covers oil pump frequency, fan speed, and heat exchanger temperature. Simultaneously, it receives remote control commands from the monitoring platform, such as adjusting safe temperature thresholds and modifying parameters of the dynamic cooling strategy, such as the lower limit of pump frequency under light load. Maintenance personnel can remotely view the equipment's operating status through the monitoring platform without on-site supervision; when system anomalies occur, such as sudden temperature increases or sensor failures, the platform receives alarm information in real time for rapid response. This implementation enhances the remote management capabilities of the cooling system, reduces maintenance costs, and strengthens data transmission reliability.

[0039] In this embodiment, the intelligent control unit for power transformers further includes: a data storage device for long-term storage of historical operating data, cooling strategy adjustment records, and fault diagnosis information; and an analysis and optimization module configured to perform in-depth analysis of historical data to continuously optimize the parameters of the dynamic cooling strategy.

[0040] Specifically, the intelligent control unit's data storage adopts a dual storage mode of industrial-grade SD card and cloud: the local SD card stores historical operating data, cooling strategy adjustment records, and fault diagnosis information for a long time. The historical operating data includes temperature, load, and cooling parameters for the past year. The cooling strategy adjustment records include the time, reason, and value of each parameter adjustment. The fault diagnosis information includes the fault type, occurrence time, and handling result, ensuring that the data is locally searchable. The cloud storage synchronizes the data to a remote server through a communication module to achieve data backup and long-term archiving.

[0041] The analysis and optimization module uses a linear regression algorithm to perform in-depth analysis of historical data, uncovering the correlation between cooling parameters and influencing factors. Cooling parameters include the frequency of the variable frequency oil pump, and influencing factors include the equivalent load rate and ambient temperature. With the goal of minimizing cooling energy consumption and achieving the required heat dissipation effect, the module optimizes the preset parameters of the dynamic cooling strategy. The core formula is as follows: The parameters in the formula are defined as follows: The optimal operating frequency of the variable frequency oil pump, in Hz; , , : Regression coefficients, where The unit is Hz. The unit is Hz. The unit is Hz, and the three values ​​are determined by fitting historical data using the least squares method. Equivalent load factor, dimensionless; The normalized ambient temperature is dimensionless, as ambient temperature is... The unit is ℃, and Because the units are different, normalization is required. The formula is: ,in The lowest ambient temperature recorded in history, expressed in °C.

[0042] In practical applications, the analysis and optimization module automatically fits historical data once a month and updates it. , , The value of . For example, by fitting, it was found that when ℃ hour, Substituting into the formula, we get At this point, cooling energy consumption is lowest and the hot spot temperature can be controlled at around 95℃. The system automatically incorporates this parameter into the dynamic cooling strategy, and when the same operating conditions are detected subsequently, this optimal frequency is directly called. This implementation method enables the dynamic cooling strategy to be continuously iterated and optimized, gradually adapting to the complex operating conditions in actual operation, and further improving energy saving effect and cooling stability.

[0043] The present invention also provides a high-efficiency and energy-saving power transformer, including a high-efficiency and energy-saving power transformer cooling system comprising any of the above-mentioned power transformers.

[0044] Specifically, the high-efficiency energy-saving power transformer includes a core, windings, tank, and insulation system. The core uses high-permeability silicon steel sheets to reduce iron losses, the windings use copper wires to reduce copper losses, the tank uses a sealed structure to reduce insulating oil loss, and the insulation system uses high-temperature resistant insulating paper to improve heat resistance. The core is a high-efficiency energy-saving cooling system that integrates any of the above components: the temperature sensor's detection end is directly embedded inside the windings, core, and tank to ensure accurate data acquisition; the load monitoring unit's acquisition module is connected in series or parallel to the transformer's main circuit, electrically isolated from the main circuit to avoid interference; the cooling execution unit's oil circulation pump, fan, and local cooling module are installed outside the tank, with the oil circuit interface sealed to the tank, and the air duct aligned with the oil-air heat exchanger; the intelligent control unit and communication module are integrated in an independent control box and connected to each unit via cables.

[0045] After installation, commissioning is conducted: simulating light load, heavy load, high temperature, and low temperature conditions, the equivalent load rate formula is used to calculate the real-time load level, and the insulation system status is verified using health index formulas to ensure timely adjustment of cooling system parameters, adequate heat dissipation, and normal data transmission. In actual operation, the low-loss characteristics of the transformer body and the high-efficiency energy-saving characteristics of the cooling system work synergistically, not only reducing the transformer's own energy loss but also reducing the additional energy consumption of the cooling system. Overall energy efficiency is significantly improved compared to traditional transformers, while extending equipment life and adapting to the operational needs of different grid loads and environmental conditions.

[0046] In summary, this invention, by arranging temperature sensors in different heat-generating areas inside the power transformer and combining them with a load monitoring unit, acquires real-time thermal state data of the windings, core, and insulating oil, as well as load data such as operating current and voltage. Based on this data, the intelligent control unit establishes a multi-region real-time thermal model, generating a dynamic cooling strategy with the goal of minimizing cooling energy consumption and ensuring cooling uniformity. It adaptively adjusts the operating parameters of the variable frequency oil pump and cooling fan in the cooling execution unit, and also uses independent local cooling modules to precisely cool hot spots. This effectively solves the problems of high energy consumption, limited cooling efficiency, uneven heat dissipation, and untimely response to load changes in traditional cooling systems. At the same time, the intelligent control unit can assess the thermal aging condition of the insulation system, and the communication module enables data uploading and remote control. This not only reduces the energy consumption of the cooling system itself and improves the overall energy efficiency of the transformer, but also extends the equipment life, facilitates operation and maintenance, and ensures the long-term stable operation of the transformer.

[0047] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0048] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-efficiency and energy-saving power transformer cooling system, characterized in that, include: Multiple temperature sensors are arranged in different heat-generating areas inside the power transformer to acquire real-time thermal status data of key parts of the power transformer, including windings, core and insulating oil. The load monitoring unit is electrically connected to the main circuit of the power transformer and is configured to acquire load data of the power transformer in real time, including operating current, operating voltage and active power. The cooling unit includes at least one oil circulation pump, at least one cooling fan, and at least one oil-air heat exchanger. The cooling unit is configured to transfer the heat generated inside the power transformer to the external environment through forced oil circulation and air cooling. The intelligent control unit is electrically connected to multiple temperature sensors, a load monitoring unit, and a cooling execution unit. The intelligent control unit is configured for: It receives and processes thermal status data acquired by multiple temperature sensors and load data acquired by a load monitoring unit; Based on the processed thermal state data and load data, combined with preset operating parameters and optimization objectives, a dynamic cooling strategy is generated to maintain the power transformer within the safe operating temperature range. The optimization objectives include minimizing the energy consumption of the cooling system itself and ensuring cooling uniformity. Based on the dynamic cooling strategy, precise control commands are sent to the cooling execution unit to adaptively adjust the operating frequency of the oil circulation pump, the speed of the cooling fan, and the heat dissipation capacity of the oil-air heat exchanger.

2. The high-efficiency and energy-saving power transformer cooling system according to claim 1, characterized in that, The plurality of temperature sensors include: at least one winding-embedded fiber optic temperature sensor, which is embedded in the heat dissipation channel of the power transformer winding for monitoring the hot spot temperature of the winding and is resistant to electromagnetic interference; and at least one resistance temperature sensor, which is arranged in the insulating oil for monitoring the average temperature of the insulating oil.

3. The high-efficiency and energy-saving power transformer cooling system according to claim 1, characterized in that, The load monitoring unit is also configured to: collect the current, voltage and active power signals of the power transformer in real time; and calculate the equivalent load rate based on the signals. The equivalent load rate is used to predict the temperature rise trend and dynamic heat dissipation requirements of the power transformer under different operating conditions.

4. The high-efficiency and energy-saving power transformer cooling system according to claim 1, characterized in that, The cooling execution unit further includes: at least one variable frequency oil pump for regulating the flow rate of cooling oil; and at least one DC brushless fan for regulating air volume and air speed; the cooling execution unit is heat exchange coupled to the power transformer body through an internal oil circuit system and an external air duct system.

5. The high-efficiency and energy-saving power transformer cooling system according to claim 1, characterized in that, The intelligent control unit is further configured to: establish a multi-region real-time thermal model of the power transformer, the thermal model being dynamically updated based on thermal state data, load data, and environmental parameters; the intelligent control unit is also used to assess the thermal aging status and current health indicators of the power transformer insulation system based on the output of the real-time thermal model.

6. The high-efficiency and energy-saving power transformer cooling system according to claim 1, characterized in that, The dynamic cooling strategy further includes: optimizing the operating parameters of the oil circulation pump and the cooling fan during light load or low temperature operation to reduce the energy consumption of the cooling system itself; and dynamically improving the operating efficiency of the pump and fan during heavy load or high temperature operation to quickly meet the heat dissipation requirements.

7. The high-efficiency and energy-saving power transformer cooling system according to claim 1, characterized in that, The cooling execution unit also includes: multiple independently controlled local cooling modules, which are arranged in specific hot spot areas of the power transformer. Each local cooling module is equipped with an independent micro fan or micro radiator for precise and rapid cooling of local hot spots.

8. The high-efficiency and energy-saving power transformer cooling system according to claim 1, characterized in that, The cooling system also includes a communication module, which is configured to upload thermal status data and cooling system operating status data to the monitoring platform in real time via an industrial-grade network interface or a wireless communication network, and to receive remote control and optimization commands.

9. The high-efficiency and energy-saving power transformer cooling system according to claim 1, characterized in that, The intelligent control unit also includes: a data storage device for long-term storage of historical operating data, cooling strategy adjustment records, and fault diagnosis information; and an analysis and optimization module configured to perform in-depth analysis of historical data to continuously optimize the parameters of the dynamic cooling strategy.

10. A high-efficiency and energy-saving power transformer, characterized in that, Including the high-efficiency and energy-saving power transformer cooling system as described in any one of claims 1-9.

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