Transformer cooling device startup temperature control method and device

Abstract

The present application discloses a method for controlling the starting temperature of a transformer cooling device, which can be applied to the transformer field. The target model, current total operating time, and preset target total operating time threshold of the transformer to be optimized are obtained; if the current total operating time exceeds the target total operating time threshold, the target operating temperature corresponding to the operating time interval where the current total operating time is located is found from the correspondence between the preset operating time interval and the operating temperature of the historical transformer; the target recommended starting temperature corresponding to the target operating temperature is found from the correspondence between the preset historical operating temperature of the transformer and the recommended starting temperature; the relationship between the historical operating temperature of the transformer and the recommended starting temperature is negatively correlated; the starting temperature of the cooling device of the transformer to be optimized is determined to be the target recommended starting temperature. This can meet the heat dissipation requirements of the transformer to be optimized and reduce the occurrence of transformer failures to be optimized.

Description

Technical Field

[0001] The present application relates to the field of transformers, and more specifically, to a method and device for controlling the startup temperature of a transformer cooling device, and a cooling device. Background Art

[0002] A transformer is a device that uses the principle of electromagnetic induction to change AC voltage. Its main functions include voltage conversion, current conversion, and impedance conversion. Transformers are essential equipment for power transmission and distribution and are widely used in industry, agriculture, transportation, urban communities, and other fields. Insulation materials used in transformers ensure safe operation and prevent electric shock accidents. During transformer operation, heat is generated from various sources, such as heat caused by transformer operating losses and heat generated by the load current flowing through the transformer windings. When a transformer operates at excessively high temperatures for extended periods, this heat increases the temperature of the insulation material, leading to aging and, in turn, insulation failure. Insulation aging and the resulting series of insulation failures are the primary sources of transformer failure.

[0003] To dissipate the heat generated during transformer operation, a cooling device must be installed. The cooling device is normally in standby mode and only activates to cool the transformer after detecting that the transformer has reached the set startup temperature. In actual operation, as the transformer and the cooling device age, the transformer's heat dissipation increases and the cooling device's efficiency decreases. With increased transformer heat dissipation and decreased cooling device efficiency, the cooling device cannot meet the transformer's heat dissipation requirements. Summary of the Invention

[0004] In view of this, the present application provides a transformer cooling device startup temperature control method, device and cooling device.

[0005] To achieve the above objectives, this application provides the following technical solutions:

[0006] A first aspect of the present application provides a method for controlling the startup temperature of a transformer cooling device, comprising:

[0007] Obtain a target model, a current total operating time, and a preset target total operating time threshold of the transformer to be optimized; the target total operating time threshold is a boundary value for the transformer to switch from an accidental failure period to a wear and tear failure period, and the target total operating time threshold is obtained based on the set service life of historical transformers of the same target model and the average failure rates corresponding to multiple preset time intervals, the average failure rate corresponding to the preset time interval is a ratio of a first number to a second number, the first number refers to the number of historical transformers whose total operating time is within the preset time interval and which have faults, and the second number refers to the total number of historical transformers whose total operating time is within the preset time interval;

[0008] If the current total operating time exceeds the target total operating time threshold, searching for the target operating temperature corresponding to the operating time interval in which the current total operating time is located from the correspondence between the preset operating time interval and the historical operating temperature of the transformer;

[0009] Searching for a target recommended startup temperature corresponding to the target operating temperature from a preset correspondence between the historical operating temperature of the transformer and the recommended startup temperature; wherein the relationship between the historical operating temperature of the transformer and the recommended startup temperature is negatively correlated;

[0010] A starting temperature of the cooling device of the transformer to be optimized is determined as the target recommended starting temperature.

[0011] In conjunction with the first aspect, in a first possible implementation manner, the step of obtaining a correspondence between the operating time interval and the historical operating temperature of the transformer includes:

[0012] Obtaining an aging reference temperature of the historical transformer; wherein, if the historical transformer operates at the aging reference temperature, the life of the historical transformer is the service life;

[0013] By formula The operating temperature of the historical transformer corresponding to the operating time interval is calculated to establish a corresponding relationship between the operating time interval and the operating temperature of the historical transformer. γ is the ratio of the number of the historical transformers with insulation faults to the number of the historical transformers with faults, 0.85≤γ≤1, t is the maximum value of the operating time interval, and λ tran (t) is the average failure rate, T age (t) is the aging reference temperature of the historical transformer, 6≤N≤10 and N is a positive integer, T top (t) is the operating temperature of the historical transformer.

[0014] In conjunction with the first aspect, in a first possible implementation manner, the step of obtaining a correspondence between the historical operating temperature of the transformer and the recommended startup temperature includes:

[0015] Obtaining a failure rate of a cooling device of the historical transformer;

[0016] By formula The recommended startup temperature corresponding to the historical transformer operating temperature is calculated to establish a corresponding relationship between the historical transformer operating temperature and the recommended startup temperature, 10≤M≤20 and M is a positive integer, B is the failure rate of the cooling device of the historical transformer, 0≤B≤0.5, T origin is the starting temperature of the cooling device of the historical transformer, F on (t, B) is the recommended starting temperature;

[0017] Where Δ(t) = T top (t)-T age (t), Δ(t) is the difference between the operating temperature of the historical transformer and the aging reference temperature of the historical transformer.

[0018] In conjunction with the first aspect, in a first possible implementation manner, the step of obtaining a preset target total running time threshold includes:

[0019] From the preset correspondence between transformer models and total operating time thresholds, find the target total operating time threshold corresponding to the target model.

[0020] In conjunction with the first aspect, in a first possible implementation, the step of obtaining a target total running time threshold corresponding to the target model includes:

[0021] Obtain the historical transformer whose transformer model is the target model;

[0022] Dividing the average failure rates of the historical transformer corresponding to the plurality of preset time intervals into failure rate intervals; the difference between the average failure rates of any two preset time intervals in the same failure rate interval is less than or equal to a preset threshold;

[0023] For each of the failure rate intervals, obtaining a probability corresponding to the failure rate interval, where the probability corresponding to the failure rate interval refers to a probability that the average failure rate of the transformer to be optimized falls within the failure rate interval;

[0024] By formula Y p =1*p max Calculate the target total operating time threshold of the historical transformer, Y p is the total running time threshold of the target, p maxis the maximum probability, and 1 is the service life of the historical transformer.

[0025] In conjunction with the first aspect, in a first possible implementation manner, the step of obtaining the probability corresponding to the failure rate interval includes:

[0026] For each of the failure rate intervals, calculating the difference between the maximum values ​​of the preset time intervals of the average failure rates of two adjacent preset time intervals in the failure rate interval;

[0027] The ratio of the sum of the differences to the service life is determined as the probability of the failure rate interval.

[0028] A second aspect of the present application provides a transformer cooling device startup temperature control device, comprising:

[0029] an acquisition unit, configured to acquire a target model, a current total operating time, and a preset target total operating time threshold of the transformer to be optimized; the target total operating time threshold is a boundary value for the transformer to switch from an accidental failure period to a wear and tear failure period, and the target total operating time threshold is obtained based on a set service life of historical transformers of the same target model and an average failure rate corresponding to a plurality of preset time intervals, the average failure rate corresponding to the preset time interval being a ratio of a first number to a second number, the first number referring to the number of historical transformers whose total operating time is within the preset time interval and which have experienced failures, and the second number referring to the total number of historical transformers whose total operating time is within the preset time interval;

[0030] A first search unit is configured to search, if the current total operating time exceeds the target total operating time threshold, for a target operating temperature corresponding to the operating time interval in which the current total operating time is located from a preset correspondence between the operating time interval and the operating temperature of the historical transformer;

[0031] A second search unit is configured to search for a target recommended startup temperature corresponding to the target operating temperature from a preset correspondence between the historical operating temperature of the transformer and the recommended startup temperature; the relationship between the historical operating temperature of the transformer and the recommended startup temperature is negatively correlated;

[0032] A determination unit is configured to determine a startup temperature of the cooling device of the transformer to be optimized as the target recommended startup temperature.

[0033] In conjunction with the second aspect, in a first possible implementation, the following further aspects may be included:

[0034] A first acquisition module is configured to acquire an aging reference temperature of the historical transformer; wherein, if the historical transformer operates at the aging reference temperature, the life of the historical transformer is the service life;

[0035] The first calculation module is used to calculate the The operating temperature of the historical transformer corresponding to the operating time interval is calculated to establish a corresponding relationship between the operating time interval and the operating temperature of the historical transformer. γ is the ratio of the number of the historical transformers with insulation faults to the number of the historical transformers with faults. t is the maximum value of the operating time interval. λ tran (t) is the average failure rate, T age (t) is the aging reference temperature of the historical transformer, 6≤N≤10 and N is a positive integer, T top (t) is the operating temperature of the historical transformer.

[0036] In conjunction with the second aspect, in a first possible implementation, the following further aspects may be included:

[0037] An obtaining module, configured to obtain a failure rate of a cooling device of the historical transformer;

[0038] The second calculation module is used to calculate the The recommended startup temperature corresponding to the historical operating temperature of the transformer is calculated to establish a corresponding relationship between the historical operating temperature of the transformer and the recommended startup temperature, where 10≤M≤20 and M is a positive integer, B is the failure rate of the cooling device of the historical transformer, 0≤B≤0.5, and T origin is the starting temperature of the cooling device of the historical transformer, F on (t, B) is the recommended starting temperature;

[0039] Where Δ(t) = T top (t)-T age (t), Δ(t) is the difference between the operating temperature of the historical transformer and the aging reference temperature of the historical transformer.

[0040] A third aspect of the present application provides a cooling device, comprising:

[0041] processor;

[0042] a memory for storing instructions executable by the processor;

[0043] The processor is configured to execute the instructions to implement any of the above-mentioned transformer cooling device startup temperature control methods.

[0044] Through the above technical solution, it can be seen that the present application provides a method for controlling the startup temperature of a transformer cooling device. First, the target model of the transformer to be optimized, the current total operating time, and a preset target total operating time threshold are obtained. The target total operating time threshold is the limit value for the transformer to switch from the accidental failure period to the wear-out failure period. The target total operating time threshold is obtained based on the set service life of historical transformers of the same target model and the average failure rate corresponding to multiple preset time intervals. The average failure rate corresponding to the preset time interval is the ratio of a first number to a second number. The first number refers to the number of historical transformers whose total operating time falls within the preset time interval and that have experienced a fault. The second number refers to the total number of historical transformers whose total operating time falls within the preset time interval. The transformer to be optimized and the historical transformer are of the same model. Therefore, the target total operating time threshold of the historical transformer can be used to equate to the target total operating time threshold of the transformer to be optimized. If the current total operating time does not exceed the target total operating time threshold, it indicates that the transformer to be optimized is in the accidental failure period; if the current total operating time exceeds the target total operating time threshold, it indicates that the transformer to be optimized is in the wear-out failure period. During this stage, as the transformer to be optimized and the cooling device age, the starting temperature of the cooling device of the transformer to be optimized needs to be changed to meet the heat dissipation requirements of the transformer to be optimized.

[0045] From the correspondence between the preset operating time interval and the historical operating temperature of the transformer, find the target operating temperature corresponding to the operating time interval in which the current total operating time is located, and from the correspondence between the preset historical operating temperature of the transformer and the recommended starting temperature, find the target recommended starting temperature corresponding to the target operating temperature. As the aging degree of the transformer to be optimized becomes higher and higher and the aging degree of the cooling device becomes higher and higher, the operating temperature of the transformer to be optimized will become higher and higher. If it is necessary to reduce the operating temperature of the transformer to be optimized to a stable range, it is necessary to change the starting temperature of the cooling device, that is, as the operating temperature of the transformer to be optimized becomes higher and higher, the starting temperature of the cooling device becomes lower and lower. In this application, the starting temperature of the cooling device of the transformer to be optimized is determined to be the above-mentioned target recommended starting temperature. Since the relationship between the historical operating temperature of the transformer and the recommended starting temperature is negatively correlated, the heat dissipation demand of the transformer to be optimized can be met, so that the heat generated by the transformer to be optimized is processed faster, so that the operating temperature of the transformer to be optimized is maintained within a stable range, the aging rate of the insulating material is delayed, and the occurrence of transformer failures to be optimized is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0047] Figure 1 is a structural diagram of a hardware architecture according to an exemplary embodiment;

[0048] Figure 2 This is a flow chart of a method for controlling startup temperature of a transformer cooling device according to an exemplary embodiment;

[0049] Figure 3 A schematic diagram of a corresponding relationship between a preset time interval and an average failure rate provided according to an exemplary embodiment;

[0050] Figure 4 A schematic diagram of a corresponding relationship between an operating time interval and an operating temperature according to an exemplary embodiment;

[0051] Figure 5 A schematic diagram of a corresponding relationship between an operating time interval and a recommended startup temperature according to an exemplary embodiment;

[0052] Figure 6 A probability graph corresponding to a failure rate interval provided according to an exemplary embodiment;

[0053] Figure 7 is a block diagram of a transformer cooling device startup temperature control device provided according to an exemplary embodiment;

[0054] Figure 8 is a block diagram of a cooling device according to an exemplary embodiment. DETAILED DESCRIPTION

[0055] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0056] The embodiments of the present application provide a method, device, and cooling device for controlling the startup temperature of a transformer cooling device. Before introducing the technical solutions provided by the embodiments of the present application, the hardware architecture involved in the present application is first described.

[0057] like Figure 1, which is a schematic diagram of the hardware architecture provided in an embodiment of the present application, and the hardware architecture includes but is not limited to: a cooling device 11 and a server 12.

[0058] Exemplarily, the cooling device 11 may be a fin radiator, a flat tube radiator, a forced oil-air cooler, or a forced oil-water cooler.

[0059] Exemplarily, the server 12 may be a single server, or a server cluster consisting of multiple servers, or a cloud computing service center.

[0060] In an optional implementation, the cooling device 11 obtains the target model, the current total operating time and the preset target total operating time threshold of the transformer to be optimized. If the current total operating time exceeds the target total operating time threshold, the target operating temperature corresponding to the operating time interval in which the current total operating time is located is searched from the correspondence between the operating time interval and the historical operating temperature of the transformer stored in the server 12. The target recommended starting temperature corresponding to the target operating temperature is searched from the correspondence between the historical operating temperature of the transformer and the recommended starting temperature stored in the server 12. Because the relationship between the historical operating temperature of the transformer and the recommended starting temperature is negatively correlated, the starting temperature of the cooling device 11 can be reduced as the current total operating time and the operating temperature of the transformer to be optimized increase, and the starting temperature of the cooling device of the transformer to be optimized is finally determined to be the target recommended starting temperature, which can meet the heat dissipation requirements of the transformer to be optimized, slow down the aging rate of the transformer to be optimized, and reduce the occurrence of transformer failures.

[0061] Those skilled in the art should understand that the above-mentioned cooling devices and servers are only examples. Other existing or future cooling devices or servers that are applicable to the present disclosure should also be included in the scope of protection of the present disclosure and are included here by reference.

[0062] In an optional implementation, the correspondence between the operating time interval and the historical operating temperature of the transformer, and the correspondence between the historical operating temperature of the transformer and the recommended startup temperature are stored in the cooling device.

[0063] The following describes a method for controlling the startup temperature of a transformer cooling device provided in an embodiment of the present application in combination with the above hardware architecture.

[0064] See also Figure 2 , Figure 2 The flowchart of a method for controlling the startup temperature of a transformer cooling device according to an exemplary embodiment is provided. The method can be applied to the above cooling device. The method includes the following steps S201 to S204 during implementation.

[0065] Step S201: Obtain the target model, current total operating time and preset target total operating time threshold of the transformer to be optimized; the target total operating time threshold is the boundary value for the transformer to switch from the accidental failure period to the wear and tear failure period, and the target total operating time threshold is obtained based on the set service life of historical transformers with the same target model and the average failure rate corresponding to multiple preset time intervals, the average failure rate corresponding to the preset time interval is the ratio of the first number to the second number, the first number refers to the number of historical transformers whose total operating time is within the preset time interval and which have faults, and the second number refers to the total number of historical transformers whose total operating time is within the preset time interval.

[0066] The terms included in the above step S201 are explained below.

[0067] The current total operating time is the total operating time of the transformer to be optimized from the time it is put into use to the current moment.

[0068] Transformers have two phases: the accidental failure period and the wear-out failure period. The target total operating time threshold is the boundary between these two phases. The accidental failure period refers to the period after a transformer has been in operation for a period of time, when the probability of failure decreases to a low level, remains essentially stable, and is approximately constant. The wear-out failure period refers to the period after a transformer has been in operation for a considerable period of time, when the probability of failure increases significantly with the current operating time.

[0069] The set service life is the service life marked on the historical transformer when it leaves the factory.

[0070] A historical transformer is one that has been in operation for a certain period of time. This period can be any period within the transformer's service life, or it can be the same as the service life. The threshold between the accidental failure period and the wear-out failure period for a historical transformer is known.

[0071] It can be understood that the model of the historical transformer is the same as the target model of the transformer to be optimized, which means that the information of the historical transformer and the transformer to be optimized are consistent in all aspects, so the target total operating time threshold of the historical transformer can be used to be equivalent to the target total operating time threshold of the transformer to be optimized.

[0072] Exemplarily, the target model of the transformer to be optimized includes but is not limited to: symbols representing the number of phases / cooling method / voltage regulation method / winding core, rated capacity, rated voltage, and winding connection method.

[0073] For example, the target model of the transformer to be optimized is "SFSZ9-31500 / 110." The symbol "S" indicates that the transformer is a three-phase transformer, the symbol "F" indicates that the cooling method is air cooling, the symbol "S" indicates that the winding core is three-winding, the symbol "Z" indicates that the voltage regulation method is on-load tap change, and the symbol "9" indicates the design serial number, which is type 9. The symbol "31500" indicates that the rated capacity of the transformer to be optimized is 31500 kVA, and the symbol "110" indicates that the rated voltage of the transformer to be optimized is 110 kV.

[0074] In an optional implementation, there are multiple methods for obtaining the average failure rate corresponding to the preset time interval. The embodiments of the present application provide but are not limited to the following two methods.

[0075] The first method for obtaining the average failure rate corresponding to the preset time interval includes the following steps A11 to A13. The following steps A11 to A13 are performed for each preset time interval.

[0076] Step A11: Obtain a first number of historical transformers whose total operating time has caused faults within a preset time interval.

[0077] Step A12: Obtain the total number of historical transformers whose total operating time is within the preset time interval.

[0078] Step A13: Determine the first number / the second number as the average failure rate.

[0079] Assume that the preset time interval is [January 1st of the 20th year of total operation time, March 31st of the 20th year of total operation time], if the number of historical transformers that have failed within the preset time interval is 30, and the total number of historical transformers within the preset time interval is 100, then the average failure rate = 30 / 100*100% = 30%.

[0080] For example, the lengths of different preset time intervals can be the same or different. Figure 3 As shown, taking the historical transformer model SFPSZ7-120000 / 220 as an example, the service life is set to 30 years. The average failure rates corresponding to multiple preset time intervals are counted, and a data point distribution diagram of the average failure rate is drawn. The lengths of the multiple preset time intervals are different. Each preset time interval corresponds to a data point of the average failure rate. The average failure rate corresponding to the preset time interval [January 1 of the 20th year of total operation time, May 31 of the 20th year of total operation time] is 5.83%, and the average failure rate corresponding to the preset time interval [June 1 of the 20th year of total operation time, December 31 of the 20th year of total operation time] is 7.05%.

[0081] In an optional implementation, the historical transformers may be distributed across different regions. During step A11, a first number of historical transformers that have failed within a preset time interval within at least some regions may be selected. In this case, the second number is the total number of historical transformers within the preset time interval within at least some regions.

[0082] Step S202: If the current total operating time exceeds the target total operating time threshold, the target operating temperature corresponding to the operating time interval in which the current total operating time is located is searched from the correspondence between the preset operating time interval and the historical operating temperature of the transformer.

[0083] It can be understood that if the current total operating time exceeds the target total operating time threshold, it means that the transformer to be optimized is in the wear and tear failure period. At this stage, the transformer to be optimized cannot discharge heat in time due to increased heat dissipation and aging of the transformer. At this stage, it is necessary to change the starting temperature of the cooling device of the transformer to be optimized, so the step of searching for the target operating temperature corresponding to the operating time interval where the current total operating time is located from the correspondence between the preset operating time interval and the operating temperature of the historical transformer is executed.

[0084] For example, if the current total operating time does not exceed the target total operating time threshold, it means that the transformer to be optimized is in the accidental failure period. At this stage, the average failure rate of the transformer to be optimized is in a stable range, and the starting temperature of the cooling device of the transformer to be optimized remains unchanged.

[0085] Exemplarily, the historical operating temperature of the transformer is the temperature of the winding during the operation of the historical transformer.

[0086] Exemplarily, the durations of the various running time intervals are the same or different.

[0087] Exemplarily, the operating temperature of the historical transformer corresponding to the operating time interval is an average operating temperature of the historical transformer within the operating time interval.

[0088] For example, assuming that the duration of each operating time interval is the same, that is, 1 year, the historical operating temperature of the transformer is 98°C in the 20th year after being put into use, the operating temperature is 99°C in the 21st year after being put into use, and the operating temperature is 100°C in the 22nd year after being put into use; therefore, the correspondence between the preset operating time intervals and the historical operating temperatures of the transformer is: the operating temperature of the historical transformer corresponding to the operating time interval [January 1 of the 20th year, December 31 of the 20th year] is 98°C, the operating temperature of the historical transformer corresponding to the operating time interval [January 1 of the 21st year, December 31 of the 21st year] is 99°C, and the operating temperature of the historical transformer corresponding to the operating time interval [January 1 of the 22nd year, December 31 of the 22nd year] is 100°C. If the current total operating time of the transformer to be optimized is twenty-one years and three months, the current total operating time is in the operating time interval [January 1 of the 21st year, December 31 of the 21st year], so the target operating temperature is 99°C.

[0089] Step S203: searching for a target recommended startup temperature corresponding to the target operating temperature from a preset correspondence between the historical transformer operating temperature and the recommended startup temperature; the historical transformer operating temperature and the recommended startup temperature are negatively correlated.

[0090] It is understandable that the longer the historical transformer has been in use, that is, the longer the current total operating time, the higher the target operating temperature corresponding to the operating time interval within which the current total operating time falls. This indicates that as the current total operating time of the historical transformer increases, the heat generated during operation of the historical transformer cannot be dissipated in a timely manner, possibly due to reasons such as the aging of the historical transformer and the aging of the cooling device, resulting in the historical transformer's operating temperature becoming increasingly higher. The starting temperature of the historical transformer's cooling device needs to be lowered to dissipate the heat generated during operation more quickly, thereby maintaining the historical transformer's operating temperature within a stable range, delaying the aging of the historical transformer and reducing the probability of failure. Therefore, the relationship between the historical transformer's operating temperature and the recommended starting temperature is negatively correlated, which can meet this requirement.

[0091] Step S204: determining the startup temperature of the cooling device of the transformer to be optimized as the target recommended startup temperature.

[0092] Exemplarily, the cooling methods of the cooling device of the transformer to be optimized include but are not limited to oil-immersed air cooling and forced oil circulation.

[0093] Through the above technical solution, it can be seen that the present application provides a method for controlling the startup temperature of a transformer cooling device. First, the target model of the transformer to be optimized, the current total operating time, and a preset target total operating time threshold are obtained. The target total operating time threshold is the limit value for the transformer to switch from the accidental failure period to the wear-out failure period. The target total operating time threshold is obtained based on the set service life of historical transformers of the same target model and the average failure rate corresponding to multiple preset time intervals. The average failure rate corresponding to the preset time interval is the ratio of a first number to a second number. The first number refers to the number of historical transformers whose total operating time falls within the preset time interval and that have experienced a fault. The second number refers to the total number of historical transformers whose total operating time falls within the preset time interval. The transformer to be optimized and the historical transformer are of the same model. Therefore, the target total operating time threshold of the historical transformer can be used to equate to the target total operating time threshold of the transformer to be optimized. If the current total operating time does not exceed the target total operating time threshold, it indicates that the transformer to be optimized is in the accidental failure period; if the current total operating time exceeds the target total operating time threshold, it indicates that the transformer to be optimized is in the wear-out failure period. During this stage, as the transformer to be optimized and the cooling device age, the starting temperature of the cooling device of the transformer to be optimized needs to be changed to meet the heat dissipation requirements of the transformer to be optimized.

[0094] From the correspondence between the preset operating time interval and the historical operating temperature of the transformer, find the target operating temperature corresponding to the operating time interval in which the current total operating time is located, and from the correspondence between the preset historical operating temperature of the transformer and the recommended starting temperature, find the target recommended starting temperature corresponding to the target operating temperature. As the aging degree of the transformer to be optimized becomes higher and higher and the aging degree of the cooling device becomes higher and higher, the operating temperature of the transformer to be optimized will become higher and higher. If it is necessary to reduce the operating temperature of the transformer to be optimized to a stable range, it is necessary to change the starting temperature of the cooling device, that is, as the operating temperature of the transformer to be optimized becomes higher and higher, the starting temperature of the cooling device becomes lower and lower. In this application, the starting temperature of the cooling device of the transformer to be optimized is determined to be the above-mentioned target recommended starting temperature. Since the relationship between the historical operating temperature of the transformer and the recommended starting temperature is negatively correlated, the heat dissipation demand of the transformer to be optimized can be met, so that the heat generated by the transformer to be optimized is processed faster, so that the operating temperature of the transformer to be optimized is maintained within a stable range, the aging rate of the insulating material is delayed, and the occurrence of transformer failures to be optimized is reduced.

[0095] It is understandable that after obtaining the historical average transformer failure rate data, this data needs to be analyzed and statistically analyzed to obtain the corresponding relationship between the operating time interval and the historical transformer operating temperature. Based on this, the embodiment of the present application provides but is not limited to the implementation method of steps B11 to B12 below.

[0096] Step B11: obtaining an aging reference temperature of the historical transformer; wherein, if the historical transformer operates at the aging reference temperature, the life of the historical transformer is the service life.

[0097] For example, Figure 3 As shown in Figure 2, the aging reference temperature of this model of historical transformer is 98°C.

[0098] Step B12: By formula The operating temperature of the historical transformer corresponding to the operating time interval is calculated to establish a corresponding relationship between the operating time interval and the operating temperature of the historical transformer. γ is the ratio of the number of the historical transformers with insulation faults to the number of the historical transformers with faults, 0.85≤γ≤1, t is the maximum value of the operating time interval, and λ tran (t) is the average failure rate, T age (t) is the aging reference temperature of the historical transformer, 6≤N≤10 and N is a positive integer, T top (t) is the operating temperature of the historical transformer.

[0099] formula It is obtained by combining the reliability function R(t) of the historical transformer and the insulation life cycle L(t) of the historical transformer. The insulation life cycle L(t) of the historical transformer is the ratio of the predicted insulation life to the service life. The reliability function R(t) of the historical transformer refers to the number of historical transformers that have not had any faults at time t divided by the total number of historical transformers.

[0100] Specifically, the insulation life cycle of the historical transformer is In 1930, VM Montsinger first proposed the relationship between the insulation life and the operating temperature of the transformer, namely the 10°C rule, which states that for every 10°C increase in operating temperature, the insulation life is approximately halved. However, in reality, the aging rates of different insulations should be different, so the 10°C rule cannot be simply applied to all insulation. In the field of transformers, the six-degree principle is usually used to estimate the insulation life of transformers, that is, during the use of the transformer, the aging rate of the transformer insulation doubles for every 6°C increase in the operating temperature of the transformer within a certain temperature range, that is, the insulation life of the transformer is reduced by half. In general, 6≤N≤10 and N is a positive integer. When N is 6°C, it corresponds to the "6-degree principle". Wherein, Δ(t)=T top (t)-T age (t), Δ(t) is the difference between the operating temperature of the historical transformer and the aging reference temperature of the historical transformer.

[0101] Specifically, the reliability function of the historical transformer is Since the lower the insulation life cycle of the historical transformer, the higher the corresponding operating temperature, the more obvious the change in the average failure rate and reliability of the historical transformer over time, so there is a corresponding relationship between the insulation life cycle of the historical transformer and the reliability of the historical transformer. γ is the ratio of the number of historical transformers with insulation failures to the total number of historical transformers with failures. When the correlation coefficient is greater than 85%, that is, γ ≥ 0.85, the insulation life cycle can be used to equate the transformer reliability, that is, γ·R(t) = L(t), and the final formula is obtained.

[0102] For example, Figure 3 As shown in FIG, the operating temperature of the historical transformer satisfies the 6-degree principle in the range of 80-130°C, so the insulation life cycle L(t) of the historical transformer adopts the 6-degree rule, that is, N=6. Assuming that the ratio of the number of the historical transformers with insulation faults to the number of the historical transformers with faults is 1, that is, γ=1, Figure 3 Substitute the discrete data of the average failure rate obtained statistically into the formula You can get Figure 4 The corresponding relationship between the operating time interval and the operating temperature of the historical transformer is shown. The solid line is the bar chart of the historical transformer operating temperature and the operating time interval calculated based on the average failure rate corresponding to the preset time interval. An obvious exponential upward trend can be seen. The dotted line is a smooth curve obtained by exponential fitting based on the discrete average failure rate data. The historical transformer operating temperature T can be obtained in the form of a continuous function. top_fit (t), the curve T obtained by fitting the continuous function form top_fit (t) is the corresponding relationship between the constructed operating time interval and the historical operating temperature of the transformer.

[0103] In an optional implementation, the method for pre-obtaining the correspondence between the historical transformer operating temperature and the recommended startup temperature includes steps C11 and C12.

[0104] Step C11: Obtain the failure rate of the cooling device of the historical transformer.

[0105] In practical applications, the failure rate of the cooling device should be considered. According to Montsinger's rule, the cooling efficiency of the cooling device decreases exponentially as the transformer's operating temperature increases. However, the failure rate of cooling devices varies depending on the device, so a statistical analysis of the actual cooling device is required to determine the failure rate.

[0106] Step C12: By formula The recommended startup temperature corresponding to the historical transformer operating temperature is calculated to establish a corresponding relationship between the historical transformer operating temperature and the recommended startup temperature, 10≤M≤20 and M is a positive integer, B is the failure rate of the cooling device of the historical transformer, 0≤B≤0.5, T origin is the starting temperature of the cooling device of the historical transformer, F on (t, B) is the recommended starting temperature;

[0107] Where Δ(t) = T top (t)-T age (t), Δ(t) is the difference between the operating temperature of the historical transformer and the aging reference temperature of the historical transformer.

[0108] In an ideal situation, if the failure rate of the cooling device is not considered, the formula F on (t) = T origin -Δ(t) to obtain the recommended startup temperature corresponding to the historical operating temperature of the transformer.

[0109] For example, different cooling devices have different failure rates, ranging from [0, 0.5]. M is the parameter corresponding to the Montsinger rule, which is generally in the range of 10≤M≤20, expressed in °C. It represents that when the operating temperature of the cooling device increases by M within a certain range, the technical indicators decrease by (1-B)*100%. M=10 corresponds to the "10-degree rule" of the cooling device.

[0110] In an optional implementation, the fitted T top_fit (t) into the formula The recommended startup temperature corresponding to the operating time interval can be obtained, and the corresponding relationship between the operating time interval and the recommended startup temperature can be constructed.

[0111] According to the current total operating time of the transformer to be optimized, a recommended starting temperature corresponding to the operating time interval in which the current total operating time falls may be determined.

[0112] For example, Figure 5 As shown, the historical transformer cooling device startup temperature was 100°C. The 10-degree rule (M = 10) is used to evaluate cooling device cooling efficiency degradation. The four curves from top to bottom are: Curve 1, the recommended startup temperature curve for an ideal cooling device with no failure rate; Curve 2, the recommended startup temperature curve with a failure rate B of 0.05; Curve 3, the recommended startup temperature curve with a failure rate B of 0.10; and Curve 4, the recommended startup temperature curve with a failure rate B of 0.15. The horizontal dashed line represents the 100°C startup temperature of the transformer cooling device to be optimized.

[0113] For transformers with cooling devices of different failure rates, even if the corresponding operating time ranges are the same, the recommended starting temperatures of the transformers are different.

[0114] For example, when the failure rate is 0.05, the recommended starting temperature for the historical transformer operating time interval [January 1 of the 15th year to December 31 of the 15th year] is set to 99.4°C, which is 0.6°C lower than the starting temperature of the cooling device at 100°C. The recommended starting temperature for the historical transformer operating time interval [January 1 of the 20th year to December 31 of the 20th year] is set to 96.8°C, which is 3.2°C lower than the starting temperature of the cooling device at 100°C. The recommended starting temperature for the historical transformer operating time interval [January 1 of the 25th year to December 31 of the 25th year] is set to 92.4°C, which is 7.6°C lower than the starting temperature of the cooling device at 100°C. When the failure rate is 0.10, the recommended starting temperature for the historical transformer operating time interval [January 1 of the 15th year to December 31 of the 15th year] is set to 98.5°C, which is 1.5°C lower than the cooling device's starting temperature of 100°C. The recommended starting temperature for the historical transformer operating time interval [January 1 of the 20th year to December 31 of the 20th year] is set to 95.1°C, which is 4.9°C lower than the cooling device's starting temperature of 100°C. The recommended starting temperature for the historical transformer operating time interval [January 1 of the 25th year to December 31 of the 25th year] is set to 89.0°C, which is 11.0°C lower than the cooling device's starting temperature of 100°C. When the failure efficiency is 0.15, the recommended starting temperature corresponding to the historical transformer operating time interval [January 1 of the 15th year to December 31 of the 15th year] is set to 97.6°C, which is 2.4°C lower than the starting temperature of the cooling device of 100°C; the recommended starting temperature corresponding to the historical transformer operating time interval [January 1 of the 20th year to December 31 of the 20th year] is set to 93.4°C, which is 6.6°C lower than the starting temperature of the cooling device of 100°C; the recommended starting temperature corresponding to the historical transformer operating time interval [January 1 of the 25th year to December 31 of the 25th year] is set to 86.1°C, which is 13.9°C lower than the starting temperature of the cooling device of 100°C.

[0115] In summary, for different transformers in the same operating time range, if the failure rate of the corresponding cooling device is greater, the recommended starting temperature is lower, and the difference from the fixed starting temperature (such as 100°C mentioned above) is greater, then if the starting temperature of the cooling device is kept unchanged, the aging of the historical transformer will be accelerated; through the transformer cooling device starting temperature control method provided in this application, the starting temperature of the cooling device can be changed, thereby reducing the aging rate of the historical transformer.

[0116] As the total operating time of the historical transformer increases, the operating temperature of the historical transformer increases, the recommended starting temperature of the cooling device of the historical transformer becomes lower, and the difference from the fixed starting temperature (such as 100°C mentioned above) becomes larger. Therefore, if the starting temperature of the cooling device is kept unchanged, the aging of the historical transformer is accelerated. The transformer cooling device starting temperature control method provided in this application can change the starting temperature of the cooling device, thereby reducing the aging rate of the historical transformer.

[0117] In an optional implementation, the server 11 can store the correspondence between the preset transformer model and the total operating time threshold. The total operating time threshold corresponding to different transformer models is different. After determining the target model of the transformer to be optimized, the target total operating time threshold corresponding to the target model is searched from the correspondence between the preset transformer model and the total operating time threshold. In this way, after the model of the transformer to be optimized is changed, the corresponding target total operating time threshold can be obtained according to the changed model of the transformer to be optimized.

[0118] It is understandable that when the historical transformer is in the accidental failure period, its average failure rate fluctuates steadily. At this time, the benefit of changing the cooling device's startup temperature is low. Therefore, the cooling device's startup setting is not changed during the accidental failure period. Therefore, a method is needed to divide the process into two stages, namely, calculating the limit value for the transformer to switch from the accidental failure period to the wear-out failure period, that is, the target total operating time threshold. Based on this, the embodiment of the present application provides an implementation method such as steps D11 to D14.

[0119] Step D11: Obtain the historical transformer whose transformer model is the target model.

[0120] Step D12: Divide the average failure rates of the historical transformer corresponding to the plurality of preset time intervals into failure rate intervals; the difference between any two average failure rates in the same failure rate interval is less than or equal to a preset threshold.

[0121] For example, Figure 6 As shown, the preset threshold is 1%, so the difference between any two average failure rates in the same failure rate interval is less than or equal to 1%. Figure 3 The average failure rates shown in Figure 3 are 5.98%, 5.83%, and 7.05%. The difference between the 5.98% and 5.83% average failure rates is less than 1%, so they are in the same failure rate range. However, the difference between the 7.05% and 5.83% average failure rates is greater than 1%, so they are not in the same failure rate range. Finally, each average failure rate shown in Figure 3 is divided into the corresponding failure rate range.

[0122] Step D13: For each of the failure rate intervals, obtain the probability corresponding to the failure rate interval, where the probability corresponding to the failure rate interval refers to the probability that the average failure rate of the transformer to be optimized belongs to the failure rate interval.

[0123] For example, the probability corresponding to each failure rate interval is as follows: Figure 6 As shown, by calculating the probability corresponding to each failure rate interval, it can be seen that the average failure rate of the transformer to be optimized belongs to the probability of each failure rate interval, thereby judging which failure rate interval the average failure rate of the transformer to be optimized belongs to has the highest probability.

[0124] In an optional implementation, the method for obtaining the probability corresponding to the failure rate interval includes but is not limited to steps E11 and E12.

[0125] Step E11: For each of the failure rate intervals, calculate the difference between the maximum values ​​of the preset time intervals of the average failure rates of two adjacent preset time intervals in the failure rate interval.

[0126] The following describes “the average failure rates of two adjacent preset time intervals”.

[0127] If the failure rate interval includes two average failure rates, the preset time intervals corresponding to the two average failure rates are adjacent; if the failure rate interval includes three or more average failure rates, the preset time intervals with the smaller difference between the maximum values ​​of the two preset time intervals are adjacent.

[0128] For example, Figure 3 As shown, assuming that the average failure rate corresponding to the preset time interval [January 1 of the 20th year, May 31 of the 20th year] is 5.83%, and the average failure rate corresponding to the preset time interval [January 1 of the 19th year, June 31 of the 19th year] is 5.98%, the average failure rate of 5.98% and the average failure rate of 5.83% are in the same failure rate range [5%, 6%], so the failure rate range [5%, 6%] always contains two average failure rates, namely, the average failure rate of 5.83% and the average failure rate of 5.98%.

[0129] Although the preset time intervals corresponding to the two average failure rates in the failure rate interval [5%, 6%] differ by 6 months, the failure rate interval [5%, 6%] only has these two average failure rates, so the preset time intervals corresponding to the two average failure rates are adjacent, and the maximum values ​​of the preset time intervals corresponding to the two average failure rates are June 31 of the 19th year and May 31 of the 20th year, respectively, so the difference between the maximum values ​​of the preset time intervals corresponding to the two average failure rates is 11 months.

[0130] Step E12: Determine the ratio of the sum of the differences to the service life as the probability of the failure rate range.

[0131] For example, in the above example, because the failure rate interval [5%, 6%] only contains two average failure rates, there is only one difference. 11 is converted into units of years, through 11 / 12 / 30*100%≈0.0306%, so the probability corresponding to the failure rate interval [5%, 6%] is determined to be 0.0306%.

[0132] Step D14: By formula Y p =1*p max Calculate the target total operating time threshold of the historical transformer, Y p is the total running time threshold of the target, p max is the maximum probability, and 1 is the service life of the historical transformer.

[0133] For example, Figure 6 As shown, the service life of the historical transformer is 30 years. The bar graph is the corresponding probability distribution graph of the historical transformer failure rate interval. The overall normal distribution is obtained. The curve is the general trend of the overall distribution obtained by using discrete probability fitting. Among them, the probability that the average failure rate of the transformer to be optimized belongs to the failure rate interval [1%, 2%] is the highest, and the maximum probability is 0.3065. From 30*0.3065 ≈ 10, it can be seen that the target total operating time threshold is 10 years. Figure 3 It can be seen that the average failure rate was stable in the first 10 years, and gradually increased after more than 10 years.

[0134] For example, by the same token, the total operating time threshold in the corresponding relationship between the transformer model and the total operating time threshold is also calculated in the above-mentioned process.

[0135] The above embodiments disclosed in the present application describe the method in detail. The method of the present application can be implemented using various devices. Therefore, the present application also discloses a device, and a specific embodiment is given below for detailed description.

[0136] See also Figure 7 , Figure 7 1 is a block diagram of a transformer cooling device startup temperature control device according to an exemplary embodiment. The device includes: an acquisition unit 71, a first search unit 72, a second search unit 73, and a determination unit 74, wherein:

[0137] an acquisition unit, configured to acquire a target model, a current total operating time, and a preset target total operating time threshold of the transformer to be optimized; the target total operating time threshold is a boundary value for the transformer to switch from an accidental failure period to a wear and tear failure period, and the target total operating time threshold is obtained based on a set service life of historical transformers of the same target model and an average failure rate corresponding to a plurality of preset time intervals, the average failure rate corresponding to the preset time interval being a ratio of a first number to a second number, the first number referring to the number of historical transformers whose total operating time is within the preset time interval and which have experienced failures, and the second number referring to the total number of historical transformers whose total operating time is within the preset time interval;

[0138] A first search unit is configured to search, if the current total operating time exceeds the target total operating time threshold, for a target operating temperature corresponding to the operating time interval in which the current total operating time is located from a preset correspondence between the operating time interval and the operating temperature of the historical transformer;

[0139] A second search unit is configured to search for a target recommended startup temperature corresponding to the target operating temperature from a preset correspondence between the historical operating temperature of the transformer and the recommended startup temperature; the relationship between the historical operating temperature of the transformer and the recommended startup temperature is negatively correlated;

[0140] A determination unit is configured to determine a startup temperature of the cooling device of the transformer to be optimized as the target recommended startup temperature.

[0141] In an optional implementation, the device for starting temperature control of the transformer cooling device further includes:

[0142] A first acquisition module is configured to acquire an aging reference temperature of the historical transformer; wherein, if the historical transformer operates at the aging reference temperature, the life of the historical transformer is the service life;

[0143] The first calculation module is used to calculate the The operating temperature of the historical transformer corresponding to the operating time interval is calculated to establish a corresponding relationship between the operating time interval and the operating temperature of the historical transformer. γ is the ratio of the number of the historical transformers with insulation faults to the number of the historical transformers with faults. t is the maximum value of the operating time interval. λ tran (t) is the average failure rate, T age (t) is the aging reference temperature of the historical transformer, 6≤N≤10 and N is a positive integer, T top (t) is the operating temperature of the historical transformer.

[0144] In an optional implementation, the device for starting temperature control of the transformer cooling device further includes:

[0145] Obtaining a module for failure rate of a cooling device of the historical transformer;

[0146] The second calculation module is used to calculate the The recommended startup temperature corresponding to the historical operating temperature of the transformer is calculated to establish a corresponding relationship between the historical operating temperature of the transformer and the recommended startup temperature, where 10≤M≤20 and M is a positive integer, B is the failure rate of the cooling device of the historical transformer, 0≤B≤0.5, and T origin is the starting temperature of the cooling device of the historical transformer, F on (t, B) is the recommended starting temperature;

[0147] Where Δ(t) = T top (t)-T age (t), Δ(t) is the difference between the operating temperature of the historical transformer and the aging reference temperature of the historical transformer.

[0148] In an optional implementation, the transformer cooling device starts the temperature control device, and the acquisition unit includes:

[0149] The search module is used to search for the target total operation time threshold corresponding to the target model from the preset correspondence between the transformer model and the total operation time threshold.

[0150] In an optional implementation, the transformer cooling device starts the temperature control device, and the acquisition unit includes:

[0151] A second acquisition module is used to acquire the historical transformer whose transformer model is the target model;

[0152] A division module is used to divide the average failure rate of the historical transformer corresponding to the plurality of preset time intervals into failure rate intervals; the difference between the average failure rates of any two preset time intervals in the same failure rate interval is less than or equal to a preset threshold;

[0153] A third acquisition module is configured to acquire, for each of the failure rate intervals, a probability corresponding to the failure rate interval, where the probability corresponding to the failure rate interval refers to a probability that the average failure rate of the transformer to be optimized falls within the failure rate interval;

[0154] The third calculation module is used to calculate the value of Y p =1*p max Calculate the target total operating time threshold of the historical transformer, Y pis the total running time threshold of the target, p max is the maximum probability, and 1 is the service life of the historical transformer.

[0155] In an optional implementation, the transformer cooling device starts the temperature control device, and the third acquisition module includes:

[0156] A fourth calculation module is configured to calculate, for each failure rate interval, a difference between the maximum values ​​of the preset time intervals of the average failure rates of two adjacent preset time intervals in the failure rate interval;

[0157] A determination module is used to determine the probability that the ratio of the sum of the differences to the service life is the failure rate interval.

[0158] Regarding the apparatus in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0159] Figure 8 The figure is a block diagram of a cooling device according to an exemplary embodiment.

[0160] The cooling device includes, but is not limited to, a processor 81 , a memory 82 , a network interface 83 , an I / O controller 84 , and a communication bus 85 .

[0161] It should be noted that those skilled in the art can understand that Figure 8 The structure of the cooling device shown in the figure does not constitute a limitation on the cooling device, and the cooling device may include Figure 8 More or fewer components may be shown, or certain components may be combined, or the components may be arranged differently.

[0162] The following combination Figure 8 A detailed introduction to the various components of the cooling device:

[0163] Processor 81 is the control center of the cooling device. It connects the various components of the cooling device using various interfaces and circuits. By running or executing software programs and / or modules stored in memory 82 and accessing data stored in memory 82, it performs various cooling device functions and processes data, thereby providing overall monitoring of the cooling device. Processor 81 may include one or more processing units; illustratively, processor 81 may integrate an application processor and a modem processor. The application processor primarily handles the operating system, user interface, and application programs, while the modem processor primarily handles wireless communications. It is understood that the modem processor may not be integrated into processor 81.

[0164] The processor 81 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present invention;

[0165] The memory 82 may include a memory, such as a high-speed random-access memory (RAM) 821 and a read-only memory (ROM) 822, and may also include a large-capacity storage device 823, such as at least one disk storage device. Of course, the cooling device may also include other hardware required for the business.

[0166] The memory 82 is used to store instructions executable by the processor 81. The processor 81 has the following functions: starting temperature control of the transformer cooling device.

[0167] A wired or wireless network interface 83 is configured to connect the cooling device to a network.

[0168] The processor 81, memory 82, network interface 83, and I / O controller 84 can be interconnected via a communication bus 85, which can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus, or an EISA (Extended Industry Standard Architecture) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc.

[0169] In an exemplary embodiment, the cooling device may be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components to perform the above-mentioned transformer cooling device startup temperature control method.

[0170] In an exemplary embodiment, the present disclosure provides a storage medium including instructions, such as a memory 82 including instructions, which can be executed by a processor 81 of a cooling device to perform the above method. Alternatively, the storage medium can be a non-transitory computer-readable storage medium, such as a ROM, random access memory (RAM), CD-ROM, magnetic tape, floppy disk, or optical data storage device.

[0171] In an exemplary embodiment, a computer-readable storage medium is also provided, which can be directly loaded into the internal memory of a computer, such as the above-mentioned memory 82, and contains software code. After being loaded and executed by the computer, the computer program can implement the above-mentioned transformer cooling device startup temperature control method.

[0172] It should be noted that the features described in the various embodiments of this specification can be replaced or combined with each other. For device or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0173] It should also be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0174] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0175] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present application. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for controlling the startup temperature of a transformer cooling device, characterized in that: include: Obtain the target model, current total operating time, and preset target total operating time threshold of the transformer to be optimized; The target total operating time threshold is a boundary value for the transformer to switch from the accidental failure period to the wear and tear failure period. The target total operating time threshold is obtained based on the set service life of historical transformers of the same target model and the average failure rates corresponding to multiple preset time intervals. The average failure rate corresponding to the preset time interval is a ratio of a first number to a second number. The first number refers to the number of historical transformers whose total operating time is within the preset time interval and that have faults. The second number refers to the total number of historical transformers whose total operating time is within the preset time interval. If the current total operating time exceeds the target total operating time threshold, searching for the target operating temperature corresponding to the operating time interval in which the current total operating time is located from the correspondence between the preset operating time interval and the historical operating temperature of the transformer; Searching for a target recommended startup temperature corresponding to the target operating temperature from a preset correspondence between the historical operating temperature of the transformer and the recommended startup temperature; wherein the relationship between the historical operating temperature of the transformer and the recommended startup temperature is negatively correlated; A starting temperature of the cooling device of the transformer to be optimized is determined as the target recommended starting temperature.

2. The method according to claim 1, characterized in that The step of obtaining the corresponding relationship between the operating time interval and the historical operating temperature of the transformer includes: Obtaining an aging reference temperature of the historical transformer; wherein, if the historical transformer operates at the aging reference temperature, the life of the historical transformer is the service life; By formula T top (t) = T age (t)-N*log[γ*EXP(-∫0 T λ tran (t)dt)] / log(2) to calculate the operating temperature of the historical transformer corresponding to the operating time interval to establish a corresponding relationship between the operating time interval and the operating temperature of the historical transformer, γ is the ratio of the number of the historical transformers with insulation faults to the number of the historical transformers with faults, 0.85≤γ≤1, T is the maximum value of the operating time interval, λ tran (t) is the average failure rate, T age (t) is the aging reference temperature of the historical transformer, 6≤N≤10 and N is a positive integer, T top (t) is the operating temperature of the historical transformer.

3. The method according to claim 1 or 2, characterized in that The step of obtaining the corresponding relationship between the historical operating temperature of the transformer and the recommended startup temperature includes: Obtaining a failure rate of a cooling device of the historical transformer; By formula The recommended startup temperature corresponding to the historical transformer operating temperature is calculated to establish a corresponding relationship between the historical transformer operating temperature and the recommended startup temperature, 10≤M≤20 and M is a positive integer, B is the failure rate of the cooling device of the historical transformer, 0≤B≤0.5, T origin is the starting temperature of the cooling device of the historical transformer, F on (t,B) is the recommended starting temperature; Where Δ(t) = T top (t)-T age (t), Δ(t) is the difference between the operating temperature of the historical transformer and the aging reference temperature of the historical transformer.

4. The method according to claim 1 or 2, characterized in that The step of obtaining a preset target total running time threshold comprises: From the preset correspondence between transformer models and total operating time thresholds, find the target total operating time threshold corresponding to the target model.

5. The method according to claim 4, characterized in that: The step of obtaining the target total running time threshold corresponding to the target model includes: Obtain the historical transformer whose transformer model is the target model; Dividing the average failure rates of the historical transformer corresponding to the plurality of preset time intervals into failure rate intervals; the difference between the average failure rates of any two preset time intervals in the same failure rate interval is less than or equal to a preset threshold; For each of the failure rate intervals, obtaining a probability corresponding to the failure rate interval, where the probability corresponding to the failure rate interval refers to a probability that the average failure rate of the transformer to be optimized falls within the failure rate interval; By formula Y p =l*p max Calculate the target total operating time threshold of the historical transformer, Y p is the total running time threshold of the target, p max is the maximum probability, and l is the service life of the historical transformer.

6. The method according to claim 5, characterized in that The step of obtaining the probability corresponding to the failure rate interval includes: For each of the failure rate intervals, calculating the difference between the maximum values ​​of the preset time intervals of the average failure rates of two adjacent preset time intervals in the failure rate interval; The ratio of the sum of the differences to the service life is determined as the probability of the failure rate interval.

7. A transformer cooling device startup temperature control device, characterized in that: include: An acquisition unit is used to obtain the target model of the transformer to be optimized, the current total operating time, and a preset target total operating time threshold; The target total operating time threshold is a boundary value for the transformer to switch from the accidental failure period to the wear and tear failure period. The target total operating time threshold is obtained based on the set service life of historical transformers of the same target model and the average failure rates corresponding to multiple preset time intervals. The average failure rate corresponding to the preset time interval is a ratio of a first number to a second number. The first number refers to the number of historical transformers whose total operating time is within the preset time interval and that have faults. The second number refers to the total number of historical transformers whose total operating time is within the preset time interval. A first search unit is configured to search, if the current total operating time exceeds the target total operating time threshold, for a target operating temperature corresponding to the operating time interval in which the current total operating time is located from a correspondence between a preset operating time interval and the operating temperature of the historical transformer; A second search unit is configured to search for a target recommended startup temperature corresponding to the target operating temperature from a preset correspondence between the historical operating temperature of the transformer and the recommended startup temperature; the relationship between the historical operating temperature of the transformer and the recommended startup temperature is negatively correlated; A determination unit is configured to determine a startup temperature of the cooling device of the transformer to be optimized as the target recommended startup temperature.

8. The device according to claim 7, characterized in that The acquisition unit includes: A first acquisition module is configured to acquire an aging reference temperature of the historical transformer; wherein, if the historical transformer operates at the aging reference temperature, the life of the historical transformer is the service life; The first calculation module is used to calculate the T top (t) = T age (t)-N*log[γ*EXP(-∫0 T λ tran (t)dt)] / log(2) to calculate the operating temperature of the historical transformer corresponding to the operating time interval to establish a corresponding relationship between the operating time interval and the operating temperature of the historical transformer, γ is the ratio of the number of the historical transformers with insulation faults to the number of the historical transformers with faults, T is the maximum value of the operating time interval, λ tran (t) is the average failure rate, T age (t) is the aging reference temperature of the historical transformer, 6≤N≤10 and N is a positive integer, T top (t) is the operating temperature of the historical transformer.

9. The device according to claim 7 or 8, characterized in that The acquisition unit includes: An obtaining module, configured to obtain a failure rate of a cooling device of the historical transformer; The second calculation module is used to calculate the The recommended startup temperature corresponding to the historical transformer operating temperature is calculated to establish a corresponding relationship between the historical transformer operating temperature and the recommended startup temperature, 10≤M≤20 and M is a positive integer, B is the failure rate of the cooling device of the historical transformer, 0≤B≤0.5, T origin is the starting temperature of the cooling device of the historical transformer, F on (t,B) is the recommended starting temperature; Where Δ(t) = T top (t)-T age (t), Δ(t) is the difference between the operating temperature of the historical transformer and the aging reference temperature of the historical transformer.

10. A cooling device, characterized in that: include: processor; a memory for storing instructions executable by the processor; The processor is configured to execute the instructions to implement the transformer cooling device startup temperature control method according to any one of claims 1 to 6.

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