Cooling oil pump control method and system for transformer, terminal and medium

Abstract

The invention belongs to the technical field of transformer cooling, and particularly discloses a cooling oil pump control method and system for a transformer, a terminal and a medium, and the method comprises the steps of obtaining a transformer signal, dividing a plurality of temperature segments and matching corresponding oil pump rotating speeds, adopting a hysteresis control mode to prevent frequent starting and stopping of an oil pump, and achieving smooth switching of the rotating speeds. And when the oil temperature and the load signal meet the preset condition, starting or stopping the cooling oil pump. According to the system, instantaneous fluctuation of oil temperature data is eliminated through fixed period sampling and moving average filtering, the oil temperature trend is predicted through a double-exponential smoothing algorithm, and the predictability and accuracy of control are improved. The invention further discloses a corresponding control system and terminal equipment thereof, and efficient and reliable transformer oil pump cooling control can be conveniently achieved in the actual operation environment.

Description

Technical Field

[0001] This invention belongs to the field of transformer cooling technology, specifically relating to a cooling oil pump control method, system, terminal, and medium for transformers. Background Technology

[0002] When a transformer operates for extended periods or under high load, it generates a significant amount of heat, causing the insulating oil temperature to rise continuously. If the cooling system fails to respond promptly or its adjustment strategy is inappropriate, the oil temperature can easily exceed limits, severely impacting the transformer's insulation performance, shortening its lifespan, and even leading to serious faults such as breakdown and power outages. Especially during periods of high summer temperatures or peak loads, the effectiveness and real-time nature of the transformer's thermal management capabilities become crucial for ensuring safe operation.

[0003] Currently, most common cooling control methods in engineering are based on fixed temperature thresholds. For example, the cooling oil pump automatically starts when the oil temperature exceeds a certain set value, and automatically stops when the oil temperature drops below the set value. While this simple on / off control logic has some practicality, it has significant technical flaws. First, its control process lacks judgment on temperature change trends, making it difficult to respond promptly to situations with rapid temperature rise rates, thus posing a risk of control lag. Second, traditional control methods typically do not consider the actual load conditions of the transformer, failing to dynamically adjust cooling demands according to load changes, resulting in low energy efficiency. Summary of the Invention

[0004] This invention addresses the problems in the prior art by providing a cooling oil pump control method, system, terminal, and medium for transformers. It solves the problem that existing control methods typically do not consider the actual load of the transformer and cannot dynamically adjust cooling requirements according to load changes, resulting in low energy utilization efficiency.

[0005] The technical solution adopted in this invention is as follows: In a first aspect, this application provides a method for controlling a cooling oil pump in a transformer, the method comprising the following steps: Step S1: Obtain the transformer top oil temperature signal and the transformer load signal; Step S2: When the oil temperature signal is within the set temperature range and the load signal exceeds the preset load percentage, start the cooling oil pump; Step S3: Divide the temperature range into at least two temperature segments. Match the corresponding oil pump speed according to the oil temperature signal in the temperature segment. There is a one-to-one correspondence between the temperature segments and the oil pump speed. Step S4: When the oil temperature signal and the load signal are both lower than their respective pump stop judgment thresholds and continue for a preset time, the cooling oil pump is stopped.

[0006] Furthermore, in step S1, obtaining the transformer top oil temperature signal includes sampling oil temperature data at a fixed period and performing a moving average filter to remove instantaneous fluctuations. Obtaining transformer load signals involves real-time calculation of the transformer's current and voltage signals, based on the following formula:

[0007] Where P is the current three-phase active power of the transformer, U is the line voltage, and I is the line current. The phase angle between voltage and current. The power factor.

[0008] Furthermore, step S1 also includes: processing the oil temperature signal using a double exponential smoothing algorithm to predict the oil temperature trend for the next cycle, with the prediction formula being:

[0009] Where t is the period, For the predicted oil temperature of the next cycle, The oil temperature for the current cycle. The oil temperature from the previous cycle. The smoothing coefficient is 0 < <1.

[0010] Furthermore, when determining whether to start the cooling oil pump, a logical expression is used:

[0011] in, As the trigger criterion, T represents the current oil temperature. This refers to the oil pump start-up temperature threshold. This represents the current load percentage. The load percentage threshold for starting the oil pump.

[0012] Furthermore, in step S3, the relationship between the oil pump speed and temperature segments is achieved through a fitting function:

[0013] The oil pump speed at the current temperature. The linear fitting coefficients within the i-th temperature segment For the piecewise boundary values ​​of temperature, satisfying .

[0014] Furthermore, the correspondence between the oil pump speed and the oil temperature signal in step S3 is realized based on an adaptive PID controller, wherein the proportional coefficient in the PID controller... Integral coefficient Differential coefficients All are adjusted in real time by a fuzzy controller, specifically including: Get the current top oil temperature of the transformer With the target reference temperature Calculation error ; Calculate the rate of change of error ; Will and Input to fuzzy controller, output adjusted ; The target speed of the oil pump is calculated based on the following adaptive function:

[0015] in, This represents the target speed of the oil pump at the current moment.

[0016] Furthermore, in step S3, during the oil temperature signal change, a hysteresis control method is used to determine the switching conditions of the oil pump speed, and the oil temperature boundaries for speed increase and decrease are set as follows: and Hysteresis control is based on the trend of oil temperature change. Dynamically adjust hysteresis bandwidth :

[0017] in, To adjust the factor, This is the minimum hysteresis bandwidth.

[0018] Secondly, this application provides a cooling oil pump control system for a transformer, the system comprising: The temperature acquisition module is used to acquire the oil temperature signal of the transformer top layer, and samples the oil temperature data at a fixed period. It uses a moving average filter to remove instantaneous fluctuations and predicts the oil temperature trend of the next period based on a double exponential smoothing algorithm. The load acquisition module is used to acquire the current and voltage signals of the transformer and calculate the current load value and its percentage relative to the transformer's rated value. The start / stop criterion judgment module is used to determine whether the current oil temperature is within the set temperature range and whether the current load percentage exceeds the set threshold, and to start or stop the cooling oil pump when the preset conditions are met; The temperature segment control module is used to divide the oil temperature range into multiple temperature segments and determine the target speed of the oil pump according to the segment in which the oil temperature is located. The target speed and the temperature segment have a one-to-one correspondence. The adaptive PID control module is used to call the fuzzy controller to adjust the proportional, integral, and derivative parameters in real time according to the temperature difference between the oil temperature and the target temperature and the temperature difference change trend, and output the corresponding oil pump control signal. The hysteresis judgment module is used to dynamically adjust the hysteresis bandwidth according to the current oil temperature trend during oil temperature changes, determine whether the oil pump speed needs to be switched, and prevent frequent start-stop due to temperature fluctuations. The control execution module is used to receive the output signals from each functional module and control the start, stop and speed adjustment of the oil pump accordingly.

[0019] Thirdly, this application provides a terminal, including: Memory for storing the cooling oil pump control program for the transformer; A processor is configured to implement the steps of the cooling oil pump control method for a transformer as described in the first aspect when executing the cooling oil pump control system for the transformer.

[0020] Fourthly, this application provides a computer-readable storage medium that stores computer instructions. When a computer reads the computer instructions in the storage medium, the computer executes the cooling oil pump control method for a transformer as described in the first aspect.

[0021] As can be seen from the above technical solutions, the advantages of the present invention are: (1) This invention obtains the transformer top oil temperature signal and the transformer load signal at the same time, and constructs a joint criterion to determine whether to start or stop the oil pump, thereby avoiding false start or stop caused by single temperature control and significantly improving the adaptability and safety of the cooling system to the transformer operating status.

[0022] (2) This method divides the oil temperature signal into multiple temperature segments and corresponds them one by one with different target speeds of the oil pump. Combined with the hysteresis control strategy, it effectively avoids frequent start-stop and ineffective operation, and takes into account both system responsiveness and energy consumption control.

[0023] (3) By dynamically adjusting the PID parameters through the fuzzy controller, the cooling oil pump can achieve both response speed and stability. It can not only adapt to load disturbances under various operating environments, but also maintain the robustness and efficiency of the cooling system under uncertain conditions.

[0024] (4) The system predicts the oil temperature trend based on the double exponential smoothing algorithm and dynamically adjusts the hysteresis bandwidth according to the rate of change of oil temperature, so that the oil pump start-up and shutdown and speed switching are more stable, avoiding frequent control actions due to local fluctuations and ensuring the reliability of transformer operation.

[0025] (5) The cooling control system consists of multiple functional modules such as temperature acquisition, load calculation, adaptive control, and hysteresis judgment. The modules work together and have clear logic, which facilitates rapid deployment and integration in embedded platforms or intelligent power distribution systems, thereby improving the engineering feasibility and industrialization value of the present invention. Attached Figure Description

[0026] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 A schematic flowchart of a cooling oil pump control method for a transformer provided for an embodiment of the present invention; Figure 2 A schematic diagram of a transformer system provided for an embodiment of the present invention.

[0028] In the diagram: 1. Transformer; 2. Liquid inlet pipe; 3. Heat sink; 4. Liquid outlet pipe. Detailed Implementation

[0029] 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.

[0030] Please see Figure 1 As shown, the present invention provides a method for controlling a cooling oil pump for a transformer, comprising the following steps: Step S1: Obtain the transformer top oil temperature signal and the transformer load signal; This step aims to monitor the transformer's operating status in real time, providing a basis for subsequent cooling control. Oil temperature is a direct indicator of whether the transformer requires cooling, while load reflects the transformer's operating intensity. Combining these two factors allows for a more scientific and reasonable start-up and shutdown decision.

[0031] The transformer top-layer oil temperature is sampled at fixed intervals, for example, every 30 seconds. After collection, a moving average filtering algorithm is applied to eliminate instantaneous fluctuations caused by external disturbances or measurement errors.

[0032] Meanwhile, by measuring the three-phase current and voltage of the transformer in real time, the current load level is calculated and converted into a percentage of the transformer's rated capacity, thus forming a load signal.

[0033] Step S2: When the oil temperature signal is within the set temperature range and the load signal exceeds the preset load percentage, start the cooling oil pump; This step is used to start the cooling oil pump, ensuring timely activation of cooling under both high temperature and high load conditions, and preventing unnecessary cooling or delayed response due to a single threshold control.

[0034] Set the oil temperature range to a reasonable upper and lower limit, such as 40 to 90 degrees Celsius. When the oil temperature is within this range and the load level exceeds 80% of the rated capacity, issue a start command to drive the cooling oil pump. To avoid false triggering, a start delay logic can be set, for example, requiring the temperature to remain above a threshold for more than 10 seconds before triggering.

[0035] Step S3: Divide the temperature range into at least two temperature segments. Match the corresponding oil pump speed according to the position of the oil temperature signal in different temperature segments. Each temperature segment and the oil pump speed have a one-to-one correspondence. By subdividing the temperature range into multiple levels, each level is matched with a different speed, which helps to achieve more flexible cooling control, ensuring the cooling effect while avoiding energy consumption and wear caused by frequent start-stop of the oil pump.

[0036] For example, the temperature range of 40 to 90 degrees Celsius can be divided into four zones: low temperature, low-temperature, medium temperature, and high temperature. In the low temperature zone, the oil pump operates at a lower speed; in the medium and high temperature zones, the speed gradually increases; and in the highest temperature zone, it operates at the highest speed. The speed setting can be configured based on the performance characteristics of the oil pump to match the cooling requirements of different temperature zones.

[0037] Step S4: When the oil temperature signal and the load signal are both lower than their respective pump stop judgment thresholds and continue for a preset time, stop the cooling oil pump. Avoid stopping cooling immediately when the load or oil temperature drops in a short time. Ensure that the cooling process is sufficiently continuous to avoid affecting the equipment life or cooling effect due to frequent start-stop.

[0038] For example, the system will only issue a stop command when the oil temperature drops below 45 degrees Celsius, the load is below 50% of the rated capacity, and this state is maintained for more than 2 minutes. The preset time can be flexibly adjusted according to the transformer's heat dissipation inertia and the performance of the oil pump to achieve more robust cooling process control.

[0039] In some embodiments, in step S1, obtaining the transformer top oil temperature signal includes sampling oil temperature data at a fixed period and performing a moving average filter to remove instantaneous fluctuations. In the cooling control process, the top oil temperature of the transformer is a key parameter for measuring the thermal state of the equipment. Directly using raw oil temperature data is susceptible to environmental disturbances and instantaneous errors in sensors, which may lead to instability in the oil pump control logic. Therefore, this step introduces a moving average filtering technique during sampling, which can effectively smooth the data curve, remove local spikes, and ensure that subsequent control decisions are based on a more stable and reliable oil temperature trend, thereby enhancing the robustness of the system.

[0040] The system continuously samples the top-layer oil temperature of the transformer at fixed time intervals, such as every 15 or 30 seconds, and uses the most recent samples as a sliding window. After each sampling, the system adds the new data value to the window, removes the oldest data point, and calculates the average of all samples within the current window as the actual oil temperature signal output for judgment.

[0041] Through this moving average process, the system can effectively suppress sudden oil temperature changes caused by external disturbances or measurement errors in a short period of time, avoiding misjudgments or frequent switching of control states. The data window size (i.e., the number of samples used for averaging) can be set according to the characteristics of on-site operation, such as selecting 5 or 10 samples as a calculation window, thereby achieving a trade-off between response speed and stability.

[0042] Obtaining transformer load signals involves real-time calculation of the transformer's current and voltage signals, based on the following formula:

[0043] Where P is the current three-phase active power of the transformer, U is the line voltage, and I is the line current. The phase angle between voltage and current. The power factor.

[0044] In some embodiments, step S1 further includes: processing the oil temperature signal using a double exponential smoothing algorithm to predict the oil temperature trend for the next cycle, wherein the prediction formula is:

[0045] Where t is the period, For the predicted oil temperature of the next cycle, The oil temperature for the current cycle. The oil temperature from the previous cycle. The smoothing coefficient is 0 < <1.

[0046] In some embodiments, a logical expression is used to determine whether to start the cooling oil pump:

[0047] in, As the trigger criterion, T represents the current oil temperature. This refers to the oil pump start-up temperature threshold. This represents the current load percentage. The load percentage threshold for starting the oil pump.

[0048] In some embodiments, in step S3, the relationship between the oil pump speed and the temperature segments is achieved through a fitting function:

[0049] The oil pump speed at the current temperature. The linear fitting coefficients within the i-th temperature segment For the piecewise boundary values ​​of temperature, satisfying .

[0050] In some embodiments, the correspondence between the oil pump speed and the oil temperature signal in step S3 is implemented based on an adaptive PID controller, wherein the proportional coefficient in the PID controller... Integral coefficient Differential coefficients All are adjusted in real time by a fuzzy controller, specifically including: Get the current top oil temperature of the transformer With the target reference temperature Calculation error ; Calculate the rate of change of error ; Will and Input to fuzzy controller, output adjusted ; The target speed of the oil pump is calculated based on the following adaptive function:

[0051] in, This represents the target speed of the oil pump at the current moment.

[0052] In some embodiments, during the change of oil temperature signal in step S3, the switching conditions of oil pump speed are determined by hysteresis control. The oil temperature boundaries for increasing and decreasing engine speed are set as follows: and Hysteresis control is based on the trend of oil temperature change. Dynamically adjust hysteresis bandwidth :

[0053] in, To adjust the factor, Minimum hysteresis bandwidth; Hysteresis control prevents repeated speed switching near the critical point by setting different acceleration and deceleration thresholds, thereby improving system stability and avoiding control logic "jitter".

[0054] Each temperature segment has upper and lower thresholds. For example, the entry condition for the medium temperature segment is an oil temperature of 60 degrees Celsius, while the exit condition is a drop to 55 degrees Celsius. The system detects the oil temperature change trend, switching to high speed when the temperature rises above the upper limit and switching back to low speed when the temperature drops below the lower limit, thus forming an effective hysteresis bandwidth.

[0055] In some embodiments, this application provides a cooling oil pump control system for a transformer, the system comprising: The temperature acquisition module is used to acquire the oil temperature signal of the transformer top layer, and samples the oil temperature data at a fixed period. It uses a moving average filter to remove instantaneous fluctuations and predicts the oil temperature trend of the next period based on a double exponential smoothing algorithm. The temperature acquisition module continuously monitors the top-layer oil temperature using an oil temperature sensor located at the top of the transformer. The system is set to a fixed sampling period, for example, collecting oil temperature data every 20 seconds. The collected data is averaged using a sliding window to reduce the impact of occasional fluctuations or short-term disturbances. Furthermore, the system applies a double exponential smoothing algorithm to model the trend of historical oil temperature data, thereby predicting oil temperature changes in the next sampling period, enabling proactive control decisions and improving the foresight of the response.

[0056] The load acquisition module is used to acquire the current and voltage signals of the transformer and calculate the current load value and its percentage relative to the transformer's rated value. The load acquisition module collects voltage and current signals in real time through voltage transformers and current transformers installed on the high-voltage or low-voltage side of the transformer. The acquired signals are then processed by the data processing unit to calculate the effective power and compare it with the transformer's rated capacity to obtain the percentage of the current operating load. This percentage is used in subsequent control logic to determine the operating status and to make decisions regarding cooling strategies.

[0057] The start / stop criterion judgment module is used to determine whether the current oil temperature is within the set temperature range and whether the current load percentage exceeds the set threshold, and to start or stop the cooling oil pump when the preset conditions are met; The start / stop criterion module takes the current oil temperature and load percentage output from the temperature and load acquisition modules as input data and sets multiple judgment thresholds, such as the start-up temperature of the cooling oil pump, the start-up load percentage, and the corresponding stop-up threshold. The module uses logical operations to determine whether the start-up or stop-up conditions are met simultaneously. If the oil temperature is within the set control range and the load level exceeds the set threshold, a start-up control command is sent; if both are below the stop-up threshold and remain below it for a set period of time, a stop command is issued to ensure the accuracy and stability of the oil pump control.

[0058] The temperature segment control module is used to divide the oil temperature range into multiple temperature segments and determine the target speed of the oil pump according to the segment in which the oil temperature is located. The target speed and the temperature segment have a one-to-one correspondence. The temperature segmentation control module presets multiple oil temperature ranges, dividing them into several non-overlapping temperature segments. Each segment corresponds one-to-one with a specific target oil pump speed. During system operation, the module determines in real time which temperature segment the current oil temperature falls into and outputs the corresponding target oil pump speed as a control command. This method achieves graded control, avoiding the coarse "all-on or all-off" adjustment of the cooling system, and improving the precision of control and energy efficiency.

[0059] The adaptive PID control module is used to call the fuzzy controller to adjust the proportional, integral, and derivative parameters in real time according to the temperature difference between the oil temperature and the target temperature and the temperature difference change trend, and output the corresponding oil pump control signal. The adaptive PID control module receives real-time oil temperature data and temperature reference values, calculates the current temperature difference and its trend, and uses this as the basis for adjustment. This module integrates a fuzzy controller, which dynamically adjusts the proportional, integral, and derivative parameters in the PID controller based on the magnitude and direction of the error, thereby outputting an optimized control signal. This control signal is directly used to set the oil pump speed, enabling the system to have self-learning and adaptive adjustment capabilities, making it particularly suitable for operating conditions with frequent fluctuations in load and ambient temperature.

[0060] The hysteresis judgment module is used to dynamically adjust the hysteresis bandwidth according to the current oil temperature trend during oil temperature changes, determine whether the oil pump speed needs to be switched, and prevent frequent start-stop due to temperature fluctuations. The hysteresis detection module analyzes the direction (heating or cooling) and rate of change of the current oil temperature, automatically adjusting the upper and lower limits of the hysteresis range to avoid frequent oil pump speed switching due to slight temperature fluctuations. Specifically, when the oil temperature is within the critical range and the fluctuation is small, the system maintains the current speed unchanged, only triggering a new speed control command when the temperature truly exceeds the hysteresis boundary. This strategy significantly reduces the oil pump switching frequency, extends equipment life, and avoids over-regulation.

[0061] The control execution module is used to receive the output signals from each functional module and control the start, stop and speed adjustment of the oil pump accordingly.

[0062] The control execution module is the execution hub of the entire system, receiving comprehensive instructions from the start / stop criterion judgment module, temperature segmented control module, adaptive PID control module, and hysteresis judgment module. Based on the priority and logical conditions of each input signal, the control execution module ultimately generates control commands and sends them to the oil pump drive system to execute start, stop, or speed adjustment actions. This module has command caching and instruction confirmation mechanisms to ensure the timeliness and accuracy of each control action, improving the closed-loop nature and reliability of the overall control process.

[0063] In some embodiments, the transformer system of this application includes a transformer 1, and multiple heat dissipation components are provided on the side end face of the transformer 1. The heat dissipation components include an outlet pipe 2 and an inlet pipe 4. The outlet pipe 2 and the inlet pipe 4 are connected by multiple heat sinks 3. The heat sinks 3 are hollow. The two ends of the heat sinks 3 are respectively connected to the outlet pipe 2 and the inlet pipe 4. The outlet pipe 4 is located directly below the inlet pipe 2.

[0064] In some embodiments, this application provides a terminal, including: Memory for storing the cooling oil pump control program for the transformer; A processor is configured to execute the steps of the cooling oil pump control method for a transformer when performing the cooling oil pump control system for the transformer.

[0065] In some embodiments, this application provides a computer-readable storage medium that stores computer instructions. When a computer reads the computer instructions in the storage medium, the computer executes the cooling oil pump control method for a transformer.

[0066] It is understood that the systems, devices, modules, or units described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions. A typical implementation device is a computer, which can be a personal computer, a laptop computer, a personal digital assistant, a tablet computer, a wearable device, or any combination of these devices.

[0067] In a typical configuration, a computer includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0068] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0069] Computer-readable media, including both permanent and non-permanent, removable and non-removable media, can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, disk storage, quantum memory, graphene-based storage media or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0070] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, use and processing of the relevant data must comply with the relevant laws, regulations and standards of the relevant countries and regions, and corresponding operation portals are provided for users to choose to authorize or refuse.

[0071] It should also be noted that 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. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0072] The foregoing has described specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.

[0073] The terminology used in one or more embodiments of this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of one or more embodiments of this specification. The singular forms “a,” “described,” and “the” used in one or more embodiments of this specification and in the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0074] It should be understood that although the terms first, second, third, etc., may be used to describe various information in one or more embodiments of this specification, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, first information may also be referred to as second information without departing from the scope of one or more embodiments of this specification, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "in response to a determination," or "when," or "in the event of a determination."

[0075] The above description is merely a preferred embodiment of one or more embodiments of this specification and is not intended to limit the scope of one or more embodiments of this specification. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments of this specification should be included within the protection scope of one or more embodiments of this specification.

Claims

1. A method for controlling a cooling oil pump in a transformer, characterized in that, Includes the following steps: Step S1: Obtain the transformer top oil temperature signal and the transformer load signal; Step S2: When the oil temperature signal is within the set temperature range and the load signal exceeds the preset load percentage, start the cooling oil pump; Step S3: Divide the temperature range into at least two temperature segments. Match the corresponding oil pump speed according to the oil temperature signal in the temperature segment. There is a one-to-one correspondence between the temperature segments and the oil pump speed. Step S4: When the oil temperature signal and the load signal are both lower than their respective pump stop judgment thresholds and continue for a preset time, the cooling oil pump is stopped.

2. The cooling oil pump control method for transformers according to claim 1, characterized in that, In step S1, obtaining the transformer top oil temperature signal includes sampling oil temperature data at a fixed period and performing a moving average filter to remove instantaneous fluctuations. Obtaining transformer load signals involves real-time calculation of the transformer's current and voltage signals, based on the following formula: Where P is the current three-phase active power of the transformer, U is the line voltage, and I is the line current. The phase angle between voltage and current. The power factor.

3. The cooling oil pump control method for transformers according to claim 2, characterized in that, Step S1 further includes: processing the oil temperature signal using a double exponential smoothing algorithm to predict the oil temperature trend for the next cycle. The prediction formula is as follows: Where t is the period, For the predicted oil temperature of the next cycle, The oil temperature for the current cycle. The oil temperature from the previous cycle. The smoothing coefficient is 0 < <1.

4. The cooling oil pump control method for transformers according to claim 1, characterized in that, The logical expression used to determine whether to start the cooling oil pump is: in, As the trigger criterion, T represents the current oil temperature. This refers to the oil pump start-up temperature threshold. This represents the current load percentage. The load percentage threshold for starting the oil pump.

5. The cooling oil pump control method for transformers according to claim 1, characterized in that, In step S3, the relationship between the oil pump speed and temperature segments is achieved through a fitting function: The oil pump speed at the current temperature. The linear fitting coefficients within the i-th temperature segment For the piecewise boundary values ​​of temperature, satisfying .

6. The cooling oil pump control method for a transformer according to claim 5, characterized in that, The correspondence between the oil pump speed and the oil temperature signal in step S3 is realized based on an adaptive PID controller, wherein the proportional coefficient in the PID controller is... Integral coefficient Differential coefficients All are adjusted in real time by a fuzzy controller, specifically including: Get the current top oil temperature of the transformer With the target reference temperature Calculation error ; Calculate the rate of change of error ; Will and Input to fuzzy controller, output adjusted ; The target speed of the oil pump is calculated based on the following adaptive function: in, This represents the target speed of the oil pump at the current moment.

7. The cooling oil pump control method for a transformer according to claim 6, characterized in that, In step S3, during the change of oil temperature signal, hysteresis control is used to determine the switching conditions of oil pump speed, and the oil temperature boundaries for speed increase and decrease are set as follows: and Hysteresis control is based on the trend of oil temperature change. Dynamically adjust hysteresis bandwidth : in, To adjust the factor, This is the minimum hysteresis bandwidth.

8. A cooling oil pump control system for a transformer, characterized in that, The system includes: The temperature acquisition module is used to acquire the oil temperature signal of the transformer top layer, and samples the oil temperature data at a fixed period. It uses a moving average filter to remove instantaneous fluctuations and predicts the oil temperature trend of the next period based on a double exponential smoothing algorithm. The load acquisition module is used to acquire the current and voltage signals of the transformer and calculate the current load value and its percentage relative to the transformer's rated value. The start / stop criterion judgment module is used to determine whether the current oil temperature is within the set temperature range and whether the current load percentage exceeds the set threshold, and to start or stop the cooling oil pump when the preset conditions are met; The temperature segment control module is used to divide the oil temperature range into multiple temperature segments and determine the target speed of the oil pump according to the segment in which the oil temperature is located. The target speed and the temperature segment have a one-to-one correspondence. The adaptive PID control module is used to call the fuzzy controller to adjust the proportional, integral, and derivative parameters in real time according to the temperature difference between the oil temperature and the target temperature and the temperature difference change trend, and output the corresponding oil pump control signal. The hysteresis judgment module is used to dynamically adjust the hysteresis bandwidth according to the current oil temperature trend during oil temperature changes, determine whether the oil pump speed needs to be switched, and prevent frequent start-stop due to temperature fluctuations. The control execution module is used to receive the output signals from each functional module and control the start, stop and speed adjustment of the oil pump accordingly.

9. A terminal, characterized in that, include: Memory for storing the cooling oil pump control program for the transformer; A processor is configured to implement the steps of the cooling oil pump control method for a transformer as described in claim 1 when executing the cooling oil pump control system for the transformer.

10. A computer-readable storage medium, characterized in that, The storage medium stores computer instructions. When the computer reads the computer instructions from the storage medium, the computer executes the cooling oil pump control method for transformers as described in claim 1.

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