A method for selecting a transformer pressure relief valve and related apparatus

Abstract

This invention discloses a method and related apparatus for selecting a transformer pressure relief valve, relating to the power industry. It obtains the transformer's basic parameters and temperature parameters, determines the maximum transient pressure the oil tank can withstand based on the voltage level, determines the insulating oil density based on the temperature parameters, and then determines the static pressure. Based on the highest oil level in the oil conservator, the maximum transient pressure the oil tank can withstand, the static pressure, and the closing and opening pressures of the pressure relief valve model, it obtains the theoretical lower and upper limits of the installation height, and determines the installation height range length corresponding to each pressure relief valve model. The model with the largest installation height range length is selected, or, from multiple models with equal and largest installation height range lengths, the model with the smallest opening pressure is selected as the optimal recommended model. This invention comprehensively considers factors such as voltage level and temperature parameters, calculates the installation height range length corresponding to each model, and then compares multiple models in parallel to select the optimal recommended model, thus improving selection efficiency and accuracy.

Description

Technical Field

[0001] This invention relates to the field of power equipment technology, and more specifically, to a method for selecting a transformer pressure relief valve and related devices. Background Technology

[0002] The pressure relief valve is an important protective device for transformers. When an internal fault occurs in the transformer, causing a sudden increase in oil pressure, the pressure relief valve opens quickly to release pressure and prevent the oil tank from bursting.

[0003] Currently, the selection process for pressure relief valves still heavily relies on manual operation: engineers need to manually check the relevant parameters of the pressure relief valves and then combine their personal experience to select the pressure relief valve that meets the system requirements from a large number of models. This traditional selection method has two major drawbacks: (1) low efficiency, because the parameter matching of pressure relief valves in complex systems needs to be checked repeatedly, resulting in a long selection process; (2) low accuracy, because the selection involves many parameters, and omissions or errors are easy to occur when selecting manually. Summary of the Invention

[0004] In view of this, the present invention discloses a method and related device for selecting a transformer pressure relief valve, so as to realize automatic selection of pressure relief valve, effectively avoid human error, and improve selection efficiency and accuracy.

[0005] A method for selecting a transformer pressure relief valve, comprising:

[0006] Obtain the basic parameters and temperature parameters of the transformer, wherein the basic parameters include at least: voltage level, maximum oil level in the oil conservator and tank cover height;

[0007] The maximum transient pressure that the oil tank can withstand is determined based on the voltage level.

[0008] Using the insulating oil density-temperature relationship function, the insulating oil density corresponding to the temperature parameter is calculated, and the static pressure per unit height is obtained based on the insulating oil density;

[0009] For each pressure relief valve model in the pressure relief valve parameter library, the highest oil level of the oil tank, the maximum transient pressure that the oil tank can withstand, the static pressure, and the closing pressure and opening pressure corresponding to the pressure relief valve model are processed to obtain the theoretical upper limit and theoretical lower limit of the installation height corresponding to the pressure relief valve model.

[0010] The theoretical lower limit of the installation height is corrected based on the height of the box cover to obtain the actual lower limit of the installation height;

[0011] The theoretical upper limit of the installation height is taken as the actual lower limit of the installation height. The length of the installation height range corresponding to the pressure relief valve model is determined based on the actual lower limit of the installation height and the actual lower limit of the installation height.

[0012] Select the model that meets the preset conditions from the pressure relief valve parameter library as the optimal recommended model of the pressure relief valve. The preset conditions are: among all pressure relief valve models, select the model with the largest installation height range; or, if there are multiple models with the same and largest installation height range, select the model with the smallest opening pressure.

[0013] Optionally, it also includes:

[0014] The actual allowable installation height range corresponding to the pressure relief valve model is determined based on the actual upper limit and the actual lower limit of the installation height.

[0015] From the actual allowable installation height range corresponding to each pressure relief valve model in the pressure relief valve parameter library, determine the target actual allowable installation height range corresponding to the optimal recommended model;

[0016] The recommended number of pressure relief valves is determined based on the oil weight included in the basic parameters and the preset oil weight covered by a single valve.

[0017] Output the optimal recommended model, the target actual allowable installation height range, and the recommended number of pressure relief valves.

[0018] Optionally, when the temperature parameter includes the transformer's minimum operating temperature and maximum operating temperature, the insulating oil density corresponding to the temperature parameter is calculated using the insulating oil density-temperature relationship function, including:

[0019] The maximum density of the insulating oil corresponding to the lowest operating temperature of the transformer is calculated using the following formula:

[0020] ;

[0021] In the formula, This indicates the maximum density of the insulating oil. This indicates the density of the insulating oil at 20℃. Indicates the coefficient of volume expansion. This indicates the minimum operating temperature of the transformer;

[0022] The minimum density of the insulating oil corresponding to the highest operating temperature of the transformer is calculated using the following formula:

[0023] ;

[0024] In the formula, This indicates the minimum density of the insulating oil. This indicates the transformer's maximum operating temperature.

[0025] Optionally, when the temperature parameter only includes the real-time temperature of the transformer, the insulating oil density corresponding to the temperature parameter is calculated using the insulating oil density-temperature relationship function, including:

[0026] ;

[0027] In the formula, Indicates the real-time density of the insulating oil. This indicates the density of the insulating oil at 20℃. Indicates the coefficient of volume expansion. This indicates the real-time temperature of the transformer.

[0028] Optionally, the process for determining the theoretical lower limit of the installation height includes:

[0029] For each pressure relief valve model, the lower limit of the installation height that meets the sealing requirements is calculated based on the highest oil level in the oil tank, the static pressure, and the closing and opening pressures corresponding to the pressure relief valve model.

[0030] The lower limit of the installation height that meets the sealing requirements is determined as the theoretical lower limit of the installation height.

[0031] Optionally, the calculation formula for the lower limit of the installation height that meets the sealing requirements is as follows:

[0032]

[0033] In the formula, This indicates the lower limit of the installation height required to meet the sealing requirements. This indicates the highest oil level in the oil tank. This indicates the closing pressure corresponding to the specified pressure relief valve model. Indicates the safety factor for sealing performance. Indicates the minimum density of insulating oil. Represents gravitational acceleration. This represents the static pressure corresponding to the minimum density of the insulating oil.

[0034] Optionally, the formula for calculating the theoretical upper limit of the installation height is as follows:

[0035] The formula for calculating the upper limit of the installation height to meet the reliability requirements for opening the pressure relief valve is as follows:

[0036]

[0037] In the formula, This indicates the upper limit of the installation height required to meet the reliability requirements for opening the pressure relief valve. This indicates the highest oil level in the oil tank. This indicates the opening pressure corresponding to the specified pressure relief valve model. This indicates that the reliability and safety factor is enabled. Indicates the maximum density of the insulating oil. Represents gravitational acceleration. This represents the static pressure corresponding to the maximum density of the insulating oil;

[0038] The calculation formula for the upper limit of the installation height that meets the requirement of the maximum transient pressure that the oil tank can withstand is as follows:

[0039]

[0040] In the formula, This indicates the upper limit of the installation height required to meet the maximum transient pressure tolerance of the fuel tank. This indicates the maximum transient pressure the fuel tank can withstand. This indicates the opening pressure corresponding to the model of the pressure relief valve;

[0041] Correspondingly, the theoretical upper limit of the installation height The expression is as follows:

[0042] .

[0043] A selection device for a transformer pressure relief valve, comprising:

[0044] The parameter acquisition unit is used to acquire the basic parameters and temperature parameters of the transformer, wherein the basic parameters include at least: voltage level, maximum oil level in the oil conservator and tank cover height;

[0045] The tank pressure determination unit is used to determine the maximum transient pressure that the tank can withstand based on the voltage level.

[0046] The oil density determination unit is used to calculate the insulating oil density corresponding to the temperature parameter using the insulating oil density-temperature relationship function, and to obtain the static pressure per unit height based on the insulating oil density.

[0047] The installation height determination unit is used to process the highest oil level of the oil tank, the maximum transient pressure that the oil tank can withstand, the static pressure, and the closing pressure and opening pressure corresponding to the pressure relief valve model for each pressure relief valve model in the pressure relief valve parameter library, so as to obtain the theoretical upper limit and theoretical lower limit of the installation height corresponding to the pressure relief valve model.

[0048] The correction unit is used to correct the theoretical lower limit of the installation height based on the height of the box cover, so as to obtain the actual lower limit of the installation height;

[0049] The length determination unit is used to take the theoretical upper limit of the installation height as the actual lower limit of the installation height, and determine the length of the installation height range corresponding to the pressure relief valve model based on the actual lower limit of the installation height and the actual lower limit of the installation height.

[0050] The selection unit is used to select the model that meets the preset conditions from the pressure relief valve parameter library as the optimal recommended model of the pressure relief valve. The preset conditions are: among all pressure relief valve models, select the model with the largest installation height range; or, if there are multiple models with the same and largest installation height range, select the model with the smallest opening pressure.

[0051] A computer storage medium storing at least one instruction, which, when executed by a processor, implements the above-described method for selecting a transformer pressure relief valve.

[0052] An electronic device, comprising: a memory and a processor;

[0053] The memory is used to store at least one instruction;

[0054] The processor is used to execute at least one instruction to implement the selection method for the transformer pressure relief valve described above.

[0055] As can be seen from the above technical solution, this invention discloses a method and related device for selecting a transformer pressure relief valve. The method obtains the basic parameters and temperature parameters of the transformer. The basic parameters include at least the voltage level, the maximum oil level in the oil conservator, and the tank cover height. The maximum transient pressure that the oil tank can withstand is determined based on the voltage level. The corresponding insulating oil density is determined based on the temperature parameters, thereby obtaining the static pressure per unit height. For each pressure relief valve model in the pressure relief valve parameter library, the maximum oil level in the oil conservator, the maximum transient pressure that the oil tank can withstand, the static pressure, and the closing and opening pressures corresponding to the pressure relief valve model are processed to obtain the theoretical upper limit and lower limit of the installation height. The theoretical lower limit of the installation height is corrected using the tank cover height to obtain the actual lower limit of the installation height. The theoretical upper limit of the installation height is used as the actual lower limit of the installation height. The installation height range length corresponding to the pressure relief valve model is determined by combining the theoretical upper limit of the installation height with the actual lower limit of the installation height. From all pressure relief valve models in the pressure relief valve parameter library, the model with the largest installation height range length is selected as the optimal recommended model; or, if there are multiple models with equal and largest installation height range lengths, the model with the smallest opening pressure is selected as the optimal recommended model. This invention comprehensively considers multiple factors such as voltage level, maximum oil level in the oil tank, tank cover height, and temperature parameters. It first accurately calculates the installation height range for each model in the pressure relief valve parameter library, then compares multiple models in parallel and automatically selects the optimal recommended model. Through algorithmic analysis and comprehensive consideration, this invention ensures stable and reliable operation of the pressure relief valve across the entire temperature range. Compared to manual selection, it not only effectively avoids human error but also improves selection efficiency and accuracy. Attached Figure Description

[0056] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the published drawings without creative effort.

[0057] Figure 1 This is a flowchart illustrating a method for selecting a transformer pressure relief valve according to an embodiment of the present invention.

[0058] Figure 2 This is a schematic diagram of the structure of a selection device for a transformer pressure relief valve disclosed in an embodiment of the present invention;

[0059] Figure 3 This is a schematic diagram of the structure of an electronic device disclosed in an embodiment of the present invention. Detailed Implementation

[0060] 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.

[0061] This invention discloses a method and related device for selecting a transformer pressure relief valve. It comprehensively considers multiple factors such as voltage level, maximum oil level in the oil conservator, tank cover height, and temperature parameters. First, it accurately calculates the installation height range corresponding to each model in the pressure relief valve parameter library. Then, it compares multiple models in parallel and automatically selects the optimal recommended model. Through algorithmic analysis and comprehensive consideration, this invention ensures stable and reliable operation of the pressure relief valve across the entire temperature range. Compared to manual selection, it not only effectively avoids human error but also improves selection efficiency and accuracy.

[0062] See Figure 1 The present invention discloses a flowchart of a method for selecting a transformer pressure relief valve, the method comprising the following steps:

[0063] Step S101: Obtain the basic parameters and temperature parameters of the transformer.

[0064] The basic parameters of a transformer include at least: voltage level and maximum oil level in the oil conservator. and lid height .

[0065] In practical applications, the basic parameters of a transformer may also include oil weight. The specific amount depends on the actual needs.

[0066] The temperature parameters of a transformer include the minimum operating temperature and the maximum operating temperature, or the temperature parameters of a transformer may only include the real-time temperature.

[0067] Step S102: Determine the maximum transient pressure that the oil tank can withstand based on the voltage level.

[0068] In practical applications, different voltage levels and different maximum transient pressures that the oil tank can withstand are preset. The correspondence is illustrated with the following examples:

[0069] 110kV-220kV: =200kPa;

[0070] 330kV-500kV: =250kPa;

[0071] 500kV-1000kV: =300kPa.

[0072] By matching the obtained voltage level with each voltage level in the preset correspondence, the matching voltage level is found, and then the maximum transient pressure that the oil tank can withstand corresponding to that voltage level is determined.

[0073] Step S103: Calculate the insulating oil density corresponding to the temperature parameter using the insulating oil density-temperature relationship function, and obtain the static pressure per unit height based on the insulating oil density.

[0074] In practical applications, the density-temperature relationship function of insulating oil can be obtained by calling the insulating oil parameter library.

[0075] In this embodiment, the insulating oil density-temperature relationship function is a linear function, expressed as follows:

[0076] (1);

[0077] In the formula, Representing temperature parameters The corresponding insulating oil density at that time, This indicates the density of the insulating oil at 20℃. =895kg / m 3 , Indicates the coefficient of volume expansion. =0.00065 / ℃.

[0078] Correspondingly, the static pressure per unit height is equal to the density of the insulating oil. With gravitational acceleration The product of =9.8m / s 2 That is, the static pressure per unit height can be expressed as .

[0079] To achieve unit standardization, the calculated static pressure per unit height can be... Divide by 1000 to obtain the final static pressure, the unit of which is kPa / m.

[0080] Step S104: For each pressure relief valve model in the pressure relief valve parameter library, process the highest oil level of the oil tank, the maximum transient pressure that the oil tank can withstand, the static pressure, and the closing pressure and opening pressure corresponding to the pressure relief valve model to obtain the theoretical upper limit and theoretical lower limit of the installation height corresponding to the pressure relief valve model.

[0081] This application pre-sets a pressure relief valve parameter library, which contains at least two pressure relief valve models, as well as the opening pressure and closing pressure corresponding to each pressure relief valve model.

[0082] Different pressure relief valve models have different opening pressures. For example, the opening pressures of three different pressure relief valve models are 55 kPa, 70 kPa and 85 kPa respectively.

[0083] Different pressure relief valve models have different closing pressures. For example, the closing pressures of three different pressure relief valve models are 29.5 kPa, 37.5 kPa, and 45.5 kPa, respectively.

[0084] In this embodiment, the theoretical upper limit and theoretical lower limit of the installation height refer to the upper and lower limits of the installation height of the pressure relief valve model, determined based on the closing pressure and opening pressure corresponding to the pressure relief valve model.

[0085] Step S105: Correct the theoretical lower limit of the installation height based on the height of the box cover to obtain the actual lower limit of the installation height.

[0086] The revised expression for the actual lower limit of the installation height is as follows:

[0087] (2);

[0088] In the formula, Indicates the model number of the pressure relief valve. Actual lower limit of installation height This indicates the theoretical lower limit of the installation height. Indicates the height of the lid.

[0089] Step S106: Take the theoretical upper limit of the installation height as the actual lower limit of the installation height, and determine the length of the installation height range corresponding to the pressure relief valve model based on the actual lower limit of the installation height and the actual lower limit of the installation height.

[0090] This embodiment is based on the pressure relief valve model. Actual installation height limit and the actual lower limit of the installation height Determine the model of the pressure relief valve. Corresponding installation height range length The expression is as follows:

[0091] (3).

[0092] Step S107: Select the model that meets the preset conditions from the pressure relief valve parameter library as the optimal recommended model of the pressure relief valve.

[0093] The preset conditions are: among all pressure relief valve models, select the model with the largest installation height range; or, if there are multiple models with the same and largest installation height range, select the model with the lowest opening pressure.

[0094] In practical applications, when obtaining the various pressure relief valve models from the pressure relief valve parameter library... Corresponding installation height range length Then, compare the installation height range length of each model. Size, and select the installation height range length. The largest model is the optimal recommended model.

[0095] If there are multiple installation height ranges If they are equal and both are the largest models, then the length is determined from the installation height range. Among multiple models that are equal and all are the largest size, select the opening pressure. The smallest model is the optimal recommended model. (Regarding the length within the installation height range...) Among multiple models that are equal and all the largest, the alternative models other than the best recommended model can be sorted according to their corresponding actual allowable installation height range, in descending order of the length of the installation height range, and then output.

[0096] In summary, this invention discloses a method for selecting a transformer pressure relief valve. The method obtains the transformer's basic parameters and temperature parameters. The basic parameters include at least the voltage level, the maximum oil level in the oil conservator, and the tank cover height. The maximum transient pressure the tank can withstand is determined based on the voltage level, and the corresponding insulating oil density is determined based on the temperature parameters, thus obtaining the static pressure per unit height. For each pressure relief valve model in the pressure relief valve parameter library, the maximum oil level in the oil conservator, the maximum transient pressure the tank can withstand, the static pressure, and the corresponding closing and opening pressures of the pressure relief valve model are processed to obtain a theoretical upper limit and a theoretical lower limit for the installation height. The theoretical lower limit is corrected using the tank cover height to obtain the actual lower limit for the installation height. The theoretical upper limit is used as the actual lower limit, and the installation height range length corresponding to the pressure relief valve model is determined based on the actual lower limit. From all pressure relief valve models in the pressure relief valve parameter library, the model with the largest installation height range length is selected as the optimal recommended model; or, if multiple models have the same and largest installation height range lengths, the model with the smallest opening pressure is selected as the optimal recommended model. This invention comprehensively considers multiple factors such as voltage level, maximum oil level in the oil tank, tank cover height, and temperature parameters. It first accurately calculates the installation height range for each model in the pressure relief valve parameter library, then compares multiple models in parallel and automatically selects the optimal recommended model. Through algorithmic analysis and comprehensive consideration, this invention ensures stable and reliable operation of the pressure relief valve across the entire temperature range. Compared to manual selection, it not only effectively avoids human error but also improves selection efficiency and accuracy.

[0097] In one embodiment, the selection method for the transformer pressure relief valve may further include:

[0098] 1) Determine the actual allowable installation height range corresponding to the pressure relief valve model based on the actual upper limit and the actual lower limit of the installation height.

[0099] In practical applications, the pressure relief valve model can also be used as a reference. Actual installation height limit and the actual lower limit of the installation height Determine the actual allowable installation height range of the pressure relief valve. .

[0100] 2) Determine the target actual allowable installation height range corresponding to the optimal recommended model from the actual allowable installation height range corresponding to each pressure relief valve model in the pressure relief valve parameter library.

[0101] 3) Determine the recommended number of pressure relief valves based on the oil weight included in the basic parameters and the preset oil weight covered by a single valve.

[0102] The recommended number of pressure relief valves is expressed as follows:

[0103] (4);

[0104] In the formula, This indicates the recommended number of pressure relief valves. Indicates oil weight. This indicates the preset single-valve coverage oil weight.

[0105] (4) Output the optimal recommended model, the target actual allowable installation height range, and the recommended number of pressure relief valves.

[0106] This embodiment outputs the optimal recommended model of the determined pressure relief valve, its corresponding target actual allowable installation height range, and the recommended number of pressure relief valves. This provides technicians with accurate and comprehensive reference for subsequent installation design, equipment selection verification, and system debugging, facilitating technicians to carry out related work efficiently.

[0107] In practical applications, the corresponding insulating oil density can be determined based on the transformer's minimum and maximum operating temperatures; alternatively, it can be determined solely based on the transformer's real-time temperature. The specific process is as follows:

[0108] In one embodiment, when the temperature parameters include the transformer's minimum operating temperature and maximum operating temperature, the process of calculating the insulating oil density corresponding to the temperature parameters using the insulating oil density-temperature relationship function includes:

[0109] Calculate the maximum density of the insulating oil corresponding to the lowest operating temperature of the transformer according to formula (5):

[0110] (5);

[0111] In the formula, This indicates the maximum density of the insulating oil. This indicates the density of the insulating oil at 20℃. =895kg / m 3 , Indicates the coefficient of volume expansion. =0.00065 / ℃, This indicates the minimum operating temperature of the transformer.

[0112] Calculate the minimum density of insulating oil corresponding to the highest operating temperature of the transformer according to formula (6):

[0113] (6);

[0114] In the formula, This indicates the minimum density of the insulating oil. This indicates the transformer's maximum operating temperature.

[0115] In one embodiment, when the temperature parameter only includes the real-time temperature of the transformer, the process of calculating the insulating oil density corresponding to the temperature parameter using the insulating oil density-temperature relationship function includes:

[0116] (7);

[0117] In the formula, Indicates the real-time density of the insulating oil. This indicates the density of the insulating oil at 20℃. Indicates the coefficient of volume expansion. This indicates the real-time temperature of the transformer.

[0118] In one embodiment, the process of determining the theoretical lower limit of the installation height according to step S104 includes:

[0119] 1) For each pressure relief valve model, calculate the lower limit of the installation height that meets the sealing requirements based on the highest oil level in the oil tank, the static pressure, and the closing and opening pressures corresponding to the pressure relief valve model.

[0120] The calculation formula for the lower limit of the installation height to meet the sealing requirements is as follows:

[0121] (8);

[0122] In the formula, This indicates the lower limit of the installation height required to meet the sealing requirements. This indicates the highest oil level in the oil tank, in mm. This indicates the closing pressure corresponding to the specified pressure relief valve model. Indicates the safety factor for sealing performance. =0.85, Indicates the minimum density of insulating oil. Represents gravitational acceleration. This represents the static pressure corresponding to the minimum density of the insulating oil, in kPa / m.

[0123] 2) The lower limit of the installation height that meets the sealing requirements is determined as the theoretical lower limit of the installation height. .

[0124] In one embodiment, the formula for calculating the theoretical upper limit of the installation height according to step S104 is as follows:

[0125] The formula for calculating the upper limit of the installation height to meet the reliability requirements for opening the pressure relief valve is as follows:

[0126]

[0127] In the formula, This indicates the upper limit of the installation height required to meet the reliability requirements for opening the pressure relief valve. This indicates the highest oil level in the oil tank. This indicates the opening pressure corresponding to the specified pressure relief valve model. This indicates that the reliability and safety factor is enabled. Indicates the maximum density of the insulating oil. Represents gravitational acceleration. This represents the static pressure corresponding to the maximum density of the insulating oil;

[0128] The calculation formula for the upper limit of the installation height that meets the requirement of the maximum transient pressure that the oil tank can withstand is as follows:

[0129] (10);

[0130] In the formula, This indicates the upper limit of the installation height required to meet the maximum transient pressure tolerance of the fuel tank. This indicates the maximum transient pressure the fuel tank can withstand. This indicates the opening pressure corresponding to the specified pressure relief valve model. =0.25;

[0131] Correspondingly, the theoretical upper limit of the installation height The expression is as follows:

[0132] (11).

[0133] For example, the selection process for a transformer pressure relief valve is as follows:

[0134] This embodiment takes a transformer with a voltage level of 10kV-220kV as an example, and the parameters obtained are as follows:

[0135] Maximum oil level in oil tank =5325mm;

[0136] Box lid height =2305mm;

[0137] Oil weight =50,000 kg;

[0138] Minimum operating temperature of transformer =-25℃;

[0139] Maximum operating temperature of transformer =40℃;

[0140] Transformer real-time temperature =30℃ (for real-time temperature mode).

[0141] The maximum transient pressure that the fuel tank can withstand is determined by looking up the pre-defined correspondence based on the voltage level. =200kPa.

[0142] Preset constants: =895kg / m 3 , =0.00065 / ℃, =9.8m / s 2 ;

[0143] Sealing safety factor =0.85, reliability safety factor enabled. =0.25, single valve coverage oil weight =23000kg.

[0144] 1. Calculate the recommended number of pressure relief valves. ;

[0145] = 50000 / 23000 = 2.1739 =3;

[0146] It is recommended to install 3 pressure relief valves.

[0147] 2. Calculate the density of the insulating oil and ;

[0148] Insulating oil density-temperature relationship function: );

[0149] 1) Dual-mode operation:

[0150] Minimum operating temperature of transformer =-25℃;

[0151] =895×[1-0.00065×(-25-20)]=895×(1+0.02925)=921.2kg / m 3 ;

[0152] =(921.2×9.8) / 1000=9.03kPa / m.

[0153] Maximum operating temperature of transformer =40℃;

[0154] =895×[1—0.00065×(40-20)]=895×(1—0.013)=883.4kg / m 3 ;

[0155] =(883.4×9.8) / 1000=8.66kPa / m.

[0156] 2) Real-time temperature mode:

[0157] Transformer real-time temperature =30℃;

[0158] =895×[1—0.00065×(30-20)]=889.2kg / m 3 ;

[0159] =(889.2×9.8) / 1000=8.71kPa / m.

[0160] 3. Calculate the allowable installation height range for each pressure relief valve model (dual operating mode).

[0161] The parameter library for pressure relief valves is shown in Table 1.

[0162]

[0163] 3.1, 55kPa model.

[0164] According to formula (8), the lower limit of the installation height that meets the sealing requirements is determined as follows:

[0165] =5325—(29.5×0.85×1000) / 9.03=2548mm;

[0166] Actual lower limit of installation height =2548mm.

[0167] According to formula (9), the upper limit of the installation height that meets the reliability requirements for opening the pressure relief valve is determined as follows:

[0168] =5325-(55×0.25×1000) / 8.66=3737mm;

[0169] According to formula (10), the upper limit of the installation height that meets the requirement of the oil tank to withstand the maximum transient pressure is determined as follows:

[0170] =[(200-55)×1000] / 9.03=16057mm;

[0171] Theoretical upper limit of installation height =min(3737,16057)=3737mm;

[0172] Actual installation height limit =3737mm.

[0173] The actual allowable installation height range for the 55kPa model is [2548, 3737] mm.

[0174] Installation height range length =3737-2548=1189mm.

[0175] Using the same calculation method as the 55kPa model, the relevant data for the 70kPa and 85kPa models can be obtained, as follows:

[0176] 3.2, 70kPa model.

[0177] Minimum installation height to meet sealing requirements: =1795mm;

[0178] Actual lower limit of installation height =1795mm;

[0179] Determine the upper limit of the installation height to meet the reliability requirements for opening the pressure relief valve: =3304mm;

[0180] Determine the upper limit of the installation height to meet the maximum transient pressure requirements of the fuel tank: =14396mm;

[0181] Theoretical upper limit of installation height =min(3304,14396)=3304mm;

[0182] Actual installation height limit =3304mm;

[0183] The actual allowable installation height range for the 70kPa model is [2305, 3304] mm.

[0184] Installation height range length =3304-2305=999mm.

[0185] 3.3, 85kPa model.

[0186] Minimum installation height to meet sealing requirements: =1041mm;

[0187] Actual lower limit of installation height =1041mm;

[0188] Determine the upper limit of the installation height to meet the reliability requirements for opening the pressure relief valve: =2871mm;

[0189] Determine the upper limit of the installation height to meet the maximum transient pressure requirements of the fuel tank: =12735mm;

[0190] Theoretical upper limit of installation height =min(2871,12735)=2871mm;

[0191] Actual installation height limit =2871mm;

[0192] The actual allowable installation height range for the 70kPa model is [2305, 2871] mm.

[0193] Installation height range length =2871-2305=566mm.

[0194] The results for each model are summarized in Table 2:

[0195]

[0196] 4. Optimal model selection.

[0197] The 55kPa model has the longest installation height range and is therefore the optimal recommended model.

[0198] Permissible height of lid extension: =3737-2305=1432mm.

[0199] 5. Calculation in real-time temperature mode (optional).

[0200] If the user selects "Use real-time temperature" =30℃, then use =8.71 kPa / m.

[0201] Taking the 55kPa model as an example, the actual lower limit of the installation height. =2446mm;

[0202] Actual installation height limit =3746mm;

[0203] The actual allowable installation height range for the 55kPa model is [2446, 3746] mm.

[0204] Installation height range length =3746—2446=1300mm;

[0205] The optimal model remains the 55kPa model.

[0206] 6. Taking the dual-mode operation as an example, the output results should include at least: the optimal recommended model, the target actual allowable installation height range, and the recommended number of pressure relief valves.

[0207] The output results may also include: voltage level, maximum transient pressure that the tank can withstand, temperature range, opening pressure, installation height range, length, alternative models, etc.

[0208] It should be noted that the selection method for transformer pressure relief valves provided by this invention can be widely applied in the design, manufacturing, and retrofitting of power transformers. Through a built-in parameter library and intelligent algorithms, the efficiency and accuracy of selection are improved, avoiding selection errors caused by factors such as temperature changes and differences in the maximum transient pressure the tank can withstand, thus enhancing the reliability of transformer operation. The system can be deployed on a local computer or cloud server and provided to designers in the form of software or an app.

[0209] Corresponding to the above method embodiments, the present invention also discloses a selection device for a transformer pressure relief valve.

[0210] See Figure 2 The present invention discloses a structural schematic diagram of a transformer pressure relief valve selection device, which includes:

[0211] The parameter acquisition unit 201 is used to acquire the basic parameters and temperature parameters of the transformer, wherein the basic parameters include at least: voltage level, maximum oil level in the oil conservator and tank cover height.

[0212] The oil tank pressure determination unit 202 is used to determine the maximum transient pressure that the oil tank can withstand based on the voltage level.

[0213] The oil density determination unit 203 is used to calculate the insulating oil density corresponding to the temperature parameter using the insulating oil density-temperature relationship function, and to obtain the static pressure per unit height based on the insulating oil density;

[0214] The installation height determination unit 204 is used to process the highest oil level of the oil tank, the maximum transient pressure that the oil tank can withstand, the static pressure, and the closing pressure and opening pressure corresponding to the pressure relief valve model for each pressure relief valve model in the pressure relief valve parameter library, so as to obtain the theoretical upper limit and theoretical lower limit of the installation height corresponding to the pressure relief valve model.

[0215] Correction unit 205 is used to correct the theoretical lower limit of the installation height according to the height of the box cover, so as to obtain the actual lower limit of the installation height;

[0216] The length determination unit 206 is used to take the theoretical upper limit of the installation height as the actual lower limit of the installation height, and determine the length of the installation height range corresponding to the pressure relief valve model based on the actual lower limit of the installation height and the actual lower limit of the installation height.

[0217] The selection unit 207 is used to select a model that meets preset conditions from the pressure relief valve parameter library as the optimal recommended model of the pressure relief valve. The preset conditions are: among all pressure relief valve models, select the model with the largest installation height range; or, if there are multiple models with the same and largest installation height range, select the model with the smallest opening pressure.

[0218] In summary, this invention discloses a selection device for a transformer pressure relief valve. It acquires basic transformer parameters and temperature parameters, including at least the voltage level, the maximum oil level in the oil conservator, and the tank cover height. Based on the voltage level, it determines the maximum transient pressure the tank can withstand. Based on the temperature parameters, it determines the corresponding insulating oil density, thereby obtaining the static pressure per unit height. For each pressure relief valve model in the pressure relief valve parameter library, it processes the maximum oil level in the oil conservator, the maximum transient pressure the tank can withstand, the static pressure, and the corresponding closing and opening pressures of the pressure relief valve model to obtain a theoretical upper limit and a theoretical lower limit for the installation height. It then corrects the theoretical lower limit for the installation height using the tank cover height to obtain the actual lower limit for the installation height. Using the theoretical upper limit as the actual lower limit, it determines the installation height range length corresponding to the pressure relief valve model. From all pressure relief valve models in the pressure relief valve parameter library, it selects the model with the largest installation height range length as the optimal recommended model; or, if multiple models have the same and largest installation height range lengths, it selects the model with the smallest opening pressure as the optimal recommended model. This invention comprehensively considers multiple factors such as voltage level, maximum oil level in the oil tank, tank cover height, and temperature parameters. It first accurately calculates the installation height range for each model in the pressure relief valve parameter library, then compares multiple models in parallel and automatically selects the optimal recommended model. Through algorithmic analysis and comprehensive consideration, this invention ensures stable and reliable operation of the pressure relief valve across the entire temperature range. Compared to manual selection, it not only effectively avoids human error but also improves selection efficiency and accuracy.

[0219] In one embodiment, the selection device for the transformer pressure relief valve may further include:

[0220] The height range determination unit is used to determine the actual allowable installation height range corresponding to the pressure relief valve model based on the actual upper limit of the installation height and the actual lower limit of the installation height.

[0221] The target range determination unit is used to determine the target actual allowable installation height range corresponding to the optimal recommended model from the actual allowable installation height range corresponding to each pressure relief valve model in the pressure relief valve parameter library;

[0222] The valve quantity determination unit is used to determine the recommended number of pressure relief valves based on the oil weight included in the basic parameters and the preset oil weight covered by a single valve.

[0223] The output unit is used to output the optimal recommended model, the target actual allowable installation height range, and the recommended number of pressure relief valves.

[0224] In one embodiment, the installation height determining unit 204 can be specifically used for:

[0225] For each pressure relief valve model, the lower limit of the installation height that meets the sealing requirements is calculated based on the highest oil level in the oil tank, the static pressure, and the closing and opening pressures corresponding to the pressure relief valve model.

[0226] The lower limit of the installation height that meets the sealing requirements is determined as the theoretical lower limit of the installation height. .

[0227] It should be noted that for the specific working principles of each component in the device embodiment, please refer to the corresponding section of the method embodiment, which will not be repeated here.

[0228] Corresponding to the above embodiments, the present invention also discloses a computer storage medium that stores at least one instruction, which, when executed by a processor, implements the steps shown in the embodiments of the method for selecting a transformer pressure relief valve.

[0229] Corresponding to the above embodiments, such as Figure 3 As shown, the present invention also provides a schematic diagram of the structure of an electronic device, which may include: a processor 1 and a memory 2;

[0230] The processor 1 and memory 2 communicate with each other via the communication bus 3.

[0231] Processor 1, for executing at least one instruction;

[0232] Memory 2 is used to store at least one instruction;

[0233] Processor 1 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention.

[0234] Memory 2 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0235] In this embodiment, the processor executes at least one instruction to implement the steps shown in the method for selecting a transformer pressure relief valve.

[0236] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. 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.

[0237] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0238] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those 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 invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for selecting a transformer pressure relief valve, characterized in that, include: Obtain the basic parameters and temperature parameters of the transformer, wherein the basic parameters include at least: voltage level, maximum oil level in the oil conservator and tank cover height; The maximum transient pressure that the oil tank can withstand is determined based on the voltage level. Using the insulating oil density-temperature relationship function, the insulating oil density corresponding to the temperature parameter is calculated, and the static pressure per unit height is obtained based on the insulating oil density; For each pressure relief valve model in the pressure relief valve parameter library, the highest oil level of the oil tank, the maximum transient pressure that the oil tank can withstand, the static pressure, and the closing pressure and opening pressure corresponding to the pressure relief valve model are processed to obtain the theoretical upper limit and theoretical lower limit of the installation height corresponding to the pressure relief valve model. The theoretical lower limit of the installation height is corrected based on the height of the box cover to obtain the actual lower limit of the installation height; The theoretical upper limit of the installation height is taken as the actual lower limit of the installation height. The length of the installation height range corresponding to the pressure relief valve model is determined based on the actual lower limit of the installation height and the actual lower limit of the installation height. Select the model that meets the preset conditions from the pressure relief valve parameter library as the optimal recommended model of the pressure relief valve. The preset conditions are: among all pressure relief valve models, select the model with the largest installation height range; or, if there are multiple models with the same and largest installation height range, select the model with the smallest opening pressure.

2. The selection method for the transformer pressure relief valve according to claim 1, characterized in that, Also includes: The actual allowable installation height range corresponding to the pressure relief valve model is determined based on the actual upper limit and the actual lower limit of the installation height. From the actual allowable installation height range corresponding to each pressure relief valve model in the pressure relief valve parameter library, determine the target actual allowable installation height range corresponding to the optimal recommended model; The recommended number of pressure relief valves is determined based on the oil weight included in the basic parameters and the preset oil weight covered by a single valve. Output the optimal recommended model, the target actual allowable installation height range, and the recommended number of pressure relief valves.

3. The method for selecting a transformer pressure relief valve according to claim 1 or 2, characterized in that, When the temperature parameters include the transformer's minimum operating temperature and maximum operating temperature, the insulating oil density corresponding to the temperature parameters is calculated using the insulating oil density-temperature relationship function, including: The maximum density of the insulating oil corresponding to the lowest operating temperature of the transformer is calculated using the following formula: ； In the formula, This indicates the maximum density of the insulating oil. This indicates the density of the insulating oil at 20℃. Indicates the coefficient of volume expansion. This indicates the minimum operating temperature of the transformer; The minimum density of the insulating oil corresponding to the highest operating temperature of the transformer is calculated using the following formula: ； In the formula, This indicates the minimum density of the insulating oil. This indicates the transformer's maximum operating temperature.

4. The selection method for the transformer pressure relief valve according to claim 1 or 2, characterized in that, When the temperature parameter only includes the real-time temperature of the transformer, the insulating oil density corresponding to the temperature parameter is calculated using the insulating oil density-temperature relationship function, including: ； In the formula, Indicates the real-time density of the insulating oil. This indicates the density of the insulating oil at 20℃. Indicates the coefficient of volume expansion. This indicates the real-time temperature of the transformer.

5. The selection method for the transformer pressure relief valve according to claim 1, characterized in that, The process for determining the theoretical lower limit of the installation height includes: For each pressure relief valve model, the lower limit of the installation height that meets the sealing requirements is calculated based on the highest oil level in the oil tank, the static pressure, and the closing and opening pressures corresponding to the pressure relief valve model. The lower limit of the installation height that meets the sealing requirements is determined as the theoretical lower limit of the installation height.

6. The selection method for the transformer pressure relief valve according to claim 5, characterized in that, The calculation formula for the lower limit of the installation height that meets the sealing requirements is as follows: In the formula, This indicates the lower limit of the installation height required to meet the sealing requirements. This indicates the highest oil level in the oil tank. This indicates the closing pressure corresponding to the specified pressure relief valve model. Indicates the safety factor for sealing performance. Indicates the minimum density of insulating oil. Represents gravitational acceleration. This represents the static pressure corresponding to the minimum density of the insulating oil.

7. The selection method for the transformer pressure relief valve according to claim 1, characterized in that, The formula for calculating the theoretical upper limit of the installation height is as follows: The formula for calculating the upper limit of the installation height to meet the reliability requirements for opening the pressure relief valve is as follows: In the formula, This indicates the upper limit of the installation height required to meet the reliability requirements for opening the pressure relief valve. This indicates the highest oil level in the oil tank. This indicates the opening pressure corresponding to the specified pressure relief valve model. This indicates that the reliability and safety factor is enabled. Indicates the maximum density of the insulating oil. Represents gravitational acceleration. This represents the static pressure corresponding to the maximum density of the insulating oil; The calculation formula for the upper limit of the installation height that meets the requirement of the maximum transient pressure that the oil tank can withstand is as follows: In the formula, This indicates the upper limit of the installation height required to meet the maximum transient pressure tolerance of the fuel tank. This indicates the maximum transient pressure the fuel tank can withstand. This indicates the opening pressure corresponding to the model of the pressure relief valve; Correspondingly, the theoretical upper limit of the installation height The expression is as follows: 。 8. A selection device for a transformer pressure relief valve, characterized in that, include: The parameter acquisition unit is used to acquire the basic parameters and temperature parameters of the transformer, wherein the basic parameters include at least: voltage level, maximum oil level in the oil conservator and tank cover height; The tank pressure determination unit is used to determine the maximum transient pressure that the tank can withstand based on the voltage level. The oil density determination unit is used to calculate the insulating oil density corresponding to the temperature parameter using the insulating oil density-temperature relationship function, and to obtain the static pressure per unit height based on the insulating oil density. The installation height determination unit is used to process the highest oil level of the oil tank, the maximum transient pressure that the oil tank can withstand, the static pressure, and the closing pressure and opening pressure corresponding to the pressure relief valve model for each pressure relief valve model in the pressure relief valve parameter library, so as to obtain the theoretical upper limit and theoretical lower limit of the installation height corresponding to the pressure relief valve model. The correction unit is used to correct the theoretical lower limit of the installation height based on the height of the box cover, so as to obtain the actual lower limit of the installation height; The length determination unit is used to take the theoretical upper limit of the installation height as the actual lower limit of the installation height, and determine the length of the installation height range corresponding to the pressure relief valve model based on the actual lower limit of the installation height and the actual lower limit of the installation height. The selection unit is used to select the model that meets the preset conditions from the pressure relief valve parameter library as the optimal recommended model of the pressure relief valve. The preset conditions are: among all pressure relief valve models, select the model with the largest installation height range; or, if there are multiple models with the same and largest installation height range, select the model with the smallest opening pressure.

9. A computer storage medium, characterized in that, The computer storage medium stores at least one instruction, which, when executed by the processor, implements the selection method for the transformer pressure relief valve as described in any one of claims 1 to 7.

10. An electronic device, characterized in that, The electronic device includes: a memory and a processor; The memory is used to store at least one instruction; The processor is used to execute at least one instruction to implement the selection method for the transformer pressure relief valve as described in any one of claims 1 to 7.

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