CN111753449A - Simulation method for acquiring hot spot temperatures of power transformer under different working conditions - Google Patents
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- 238000004088 simulation Methods 0.000 title claims abstract description 36
- 239000012530 fluid Substances 0.000 claims abstract description 35
- 238000010168 coupling process Methods 0.000 claims abstract description 29
- 230000008878 coupling Effects 0.000 claims abstract description 27
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- 238000004364 calculation method Methods 0.000 claims abstract description 21
- 238000004458 analytical method Methods 0.000 claims abstract description 18
- 230000005672 electromagnetic field Effects 0.000 claims abstract description 18
- 239000007787 solid Substances 0.000 claims abstract description 12
- 238000004804 winding Methods 0.000 claims description 33
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 22
- 238000012546 transfer Methods 0.000 claims description 20
- 239000000463 material Substances 0.000 claims description 9
- 238000009413 insulation Methods 0.000 claims description 6
- 230000004907 flux Effects 0.000 claims description 5
- 230000005684 electric field Effects 0.000 claims description 3
- 238000004134 energy conservation Methods 0.000 claims description 3
- 229910052742 iron Inorganic materials 0.000 claims description 3
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- 239000003921 oil Substances 0.000 description 43
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- 230000000704 physical effect Effects 0.000 description 3
- 229910000976 Electrical steel Inorganic materials 0.000 description 2
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Abstract
The invention aims to provide a simulation method for acquiring hot spot temperatures of a power transformer under different working conditions, which is based on the actual structure of an oil-immersed transformer, and establishes a three-dimensional simulation model of the temperature rise of the transformer by adopting a method combining a finite element method and a finite volume method, wherein the influence of factors such as an electromagnetic field, oil flow and the like on the temperature is considered, and the simulation of the hot spot temperature distribution of the transformer is realized. The method comprises the following steps: s1: establishing a three-dimensional physical model of the power transformer; s2: analyzing the electromagnetic field calculation theory of the power transformer; s3: analyzing the calculation theory of the fluid and the thermal field of the power transformer; s4: adding a corresponding physical field based on the theoretical analysis of an electromagnetic field and fluid solid heat; s5: according to the actual operation condition, field-path coupling connection under different working conditions is carried out, and parameters and boundary conditions are set; s6: carrying out multi-physical field coupling setting; s7: and (4) meshing the model based on a finite element method, and simulating to obtain the temperature distribution of the power transformer and the hot spot temperature position result thereof under different working conditions.
Description
Technical Field
The invention belongs to the field of research on loaded performance of electrical equipment, and relates to a simulation method for acquiring hot spot temperatures of a power transformer under different working conditions.
Background
The key factors influencing the working state of the power transformer in actual operation are the thermal problem and the insulation problem of the power transformer, and the temperature rise of the transformer is an important index for judging whether the transformer is in a safe and stable working state. The oil-immersed transformer mainly adopts A-level insulation, the insulation material can be aged under the influence of environment and various physical and chemical effects in the operation process, and the insulation material can be directly aged at high temperature. High temperatures during operation of power transformers accelerate the chemical reactions and the mechanical and electrical strength of the insulation is reduced very quickly, whereby the transformer is prone to failure and accidents that fall short of its expected life. According to the statistical data of transformer operation accidents released by national power grids every year, the proportion of the transformer operation accidents is very high due to overhigh temperature rise of hot spots on winding leads, the hot spot temperature of the transformer is concerned at home and abroad, and in order to ensure the safe operation of the transformer, students propose that not only the average temperature rise of the winding should not exceed the allowable temperature value, but also the hot spot temperature rise of the winding should not exceed the allowable temperature value, and the two temperatures are necessary to be measured when a temperature rise test of the transformer is carried out when the transformer is designed. If the temperature of the hot spot in the transformer can be accurately calculated, reference can be provided for the heat dissipation and cooling design of the transformer, so that the operation efficiency of the transformer is improved, the occurrence of thermal accidents is reduced, and the service life of the transformer is prolonged.
By combining the structural characteristics of the oil-immersed power transformer, a 50MVA/110kV natural oil circulation oil-immersed power transformer is taken as a prototype, the internal temperature rise characteristic of the transformer under multiple working conditions is researched based on a finite element method, a field coupling method and a fluid-solid coupling method, and the temperature and the position of a hot spot in the transformer are predicted, so that accidents can be found in time, and the service life of the transformer is prolonged as far as possible.
Disclosure of Invention
The invention aims to provide a simulation method for acquiring hot spot temperatures of a power transformer under different working conditions, which is based on the actual structure of an oil-immersed transformer, and establishes a three-dimensional simulation model of the temperature rise of the transformer by adopting a method combining a finite element method and a finite volume method, wherein the influence of factors such as an electromagnetic field, oil flow and the like on the temperature is considered, and the simulation of the hot spot temperature distribution of the transformer is realized.
In order to achieve the purpose, the invention provides the following technical scheme:
s1: establishing a three-dimensional physical model of the power transformer;
s2: analyzing the electromagnetic field calculation theory of the power transformer;
s3: analyzing the calculation theory of the fluid and the thermal field of the power transformer;
s4: adding a corresponding physical field based on the theoretical analysis of an electromagnetic field and fluid solid heat;
s5: according to the actual operation condition, field-path coupling connection under different working conditions is carried out, and parameters and boundary conditions are set;
s6: performing a multi-physical field coupling setup
S7: and (4) meshing the model based on a finite element method, and simulating to obtain the temperature distribution of the power transformer and the hot spot temperature position result thereof under different working conditions.
Further, step S1 is specifically that the power transformer is a three-dimensional physical model, and when performing the coupling analysis, an important feature of the internal structure of the model is valid and invalid, that is, some features may need to be ignored according to the type of the analysis problem. Therefore, the three-dimensional modeling is carried out by taking a 50MVA/110kV natural oil circulation oil-immersed power transformer as a prototype on the basis of the following assumptions:
(1) the high-low voltage winding is simplified into a cylindrical shape, so that calculation is facilitated;
(2) the insulation layer is very thin next to the winding thickness, so its thickness is neglected;
(3) the iron core and the iron yoke are simplified into cylinders;
(4) the electromagnetic relation of the transformer is mainly determined by the iron core and the winding, so the influence of a radiator and a structural component outside the oil tank is not considered.
Step S2 is specifically an electromagnetic field calculation theory: the Maxwell equation system is the basis for analyzing the electromagnetic thermal field problem and describes the macroscopic properties of an electromagnetic field, and the differential form of the macroscopic properties is as follows:
in the formula: d is a potential shift; h is the magnetic field intensity; b is the magnetic flux density; e is the electric field strength; ρ is the charge density; j is the current density.
In the constitutive relation, the properties of the material are all set to be isotropic, i.e., the magnetic field permittivity, the material permeability μ, and the electrical conductivity σ are all scalar quantities, E, D, B, H being related to the properties of the material.
Step S3 is specifically to calculate the temperature field of the transformer based on the fluid flow continuity equation, the momentum equation, and the energy equation. The distribution characteristics of the internal temperature field of the oil-immersed power transformer can be researched by a numerical calculation method, namely a finite element analysis method.
When the mass conservation law is applied to a fluid domain of the oil-immersed power transformer, the physical meaning of the oil flow of the oil-immersed power transformer is that the increase of the transformer oil mass in an oil tank in unit time is equal to the net mass of the transformer oil flowing into the oil tank in the same time, and the differential form of the fluid flow continuous equation is
In which rho fluid density is expressed in kg/m3；μx，μy，μzIs the velocity component of the velocity vector on the x, y, z axis; t is time in units of s.
If the transformer oil flows into an incompressible flow, rho is a constant number, and the continuous equation is as follows:
the momentum equation can be derived according to Newton's second law, and when the momentum equation is applied to the fluid domain of the oil-immersed power transformer, the physical meaning represented by the momentum equation is as follows: the increase of the oil flow in the transformer tank is equal to the sum of the forces borne by the transformer tank. The three components of the momentum equation can be expressed as:
in the formula: p is a pressureStrong, in Pa; tau isxx、τxy、τxzIs the component of the viscous stress τ in Pa; f. ofx、fy、fzIs a component of force per unit mass.
The energy conservation equation can be derived from the laws of thermodynamics, which must be followed when heat exchange occurs in a fluid. The increment of the heat energy in the transformer oil tank in unit time is equal to the sum of the heat transferred by the oil flow in unit time, the work done by the force born by the transformer oil tank and the enthalpy generation amount in the transformer oil tank.
Wherein: e is the total energy of the fluid micelles; h is the enthalpy per unit mass; k is a radical ofeffIs the effective heat transfer coefficient.
Step S4 is specifically that a corresponding physical field is added based on the theoretical analysis of electromagnetic field and fluid solid heat; namely adding four physical fields of circuit, magnetic field, heat transfer and laminar flow.
Step S5 is concretely, field coupling connection under different working conditions is carried out according to actual running conditions; according to the actual situation of the field operation of the transformer, model parameters and boundary conditions of each physical field are set, wherein the model parameters and the boundary conditions comprise a heat source of a three-phase iron core, a heat source of a primary winding and a secondary winding, temperature boundary conditions, the flowing speed and the flowing direction of fluid and the like.
The main parameters of the model are as follows: the diameter of the iron core is 600mm, the center distance of the core column is 1140mm, and the height of the window is 1525 mm. The type of the silicon steel sheet used by the transformer iron core is 30QG120, the thickness of the lamination is 0.3mm, and the lamination coefficient is 0.97. The high-voltage side winding is rated at 110kV, rated at 262.43A and 629 winding turns. The low-voltage side winding is rated at 10.5kv, rated at 2749.29a and has 104 winding turns.
TABLE 1 physical Properties of winding, core and Transformer oil
Solid heat transfer not only includes heat transfer between solids such as windings and iron cores, but also includes convection heat transfer of a transformer, so that a fluid domain control equation is introduced, wherein the equation is as follows:
in the formula: rho is the density of the transformer oil; cpIs the heat capacity under normal pressure;
is a velocity field; k is the heat transfer coefficient; q is an internal heat source.
The boundary conditions of solid heat transfer are set to restrict the temperature rise characteristic: :
wherein q is heat flux; n is the normal vector of the outflow on the boundary.
Laminar flow: the research object is natural oil circulation oil-immersed power transformer, and its inside oil flow velocity is very little, belongs to the laminar flow model, can be similar to transformer oil flow for incompressible fluid in engineering research:
wherein: mu is the dynamic viscosity of the transformer oil; rho is the density of the transformer oil;
is the principal stress tensor.
Step S6 is specifically to perform coupling setting of the thermal field and the laminar flow field according to the coupling principle, add non-isothermal laminar flow and temperature coupling, and perform coupling setting of the laminar flow and the heat transfer field.
Step S7 is specifically to carry out mesh subdivision on the model based on a finite element method, choose and refine subdivision precision, add coil geometric analysis and transient solution, set simulation time and step length, and obtain the temperature distribution result of the transformer through simulation.
The invention has the beneficial effects that: by adopting the method, the hot spot temperature distribution of the transformer under different working conditions can be obtained.
Drawings
FIG. 1 is a schematic diagram of a temperature rise characteristic simulation process of an oil-immersed transformer according to the present invention
FIG. 2 is a schematic diagram of heat generation analysis of an oil-immersed transformer, namely, a transformer loss composition diagram
FIG. 3 is a model diagram for solving the temperature field of the transformer according to the present invention
FIG. 4 is an equivalent circuit model under multiple operating conditions of the present invention
FIG. 5 is a schematic diagram of the calculation result of the core temperature under the rated condition of the present invention
FIG. 6 is a schematic diagram of the calculation result of the core temperature under overload condition according to the present invention
FIG. 7 is a schematic diagram illustrating the calculation result of the core temperature in the single-phase earth fault according to the present invention
FIG. 8 is a schematic diagram of the calculation result of the high and low voltage winding temperature under the rated working condition of the present invention
FIG. 9 is a schematic diagram of the calculation result of the high and low voltage winding temperature under overload condition according to the present invention
FIG. 10 is a schematic diagram showing the calculation results of the temperatures of the high and low voltage windings during the single-phase earth fault according to the present invention
The specific implementation mode is as follows:
the present invention will be described in detail with reference to the accompanying drawings
The invention relates to a simulation method for acquiring hot spot temperatures of a power transformer under different working conditions, which is based on the actual structure of an oil-immersed transformer, establishes a three-dimensional simulation model of the temperature rise of the transformer by adopting a method combining a finite element method and a finite volume method, and realizes the simulation of the hot spot temperature distribution of the transformer by considering the influence of factors such as an electromagnetic field, oil flow and the like on the temperature. The method comprises the following specific steps:
1. establishing three-dimensional physical model of power transformer
The transformer temperature field is established in finite element software to solve a three-dimensional model, as shown in fig. 3, when coupling analysis is carried out, an important characteristic of the internal structure of the model is effective and ineffective, namely certain characteristics sometimes need to be ignored according to the type of an analysis problem. Therefore, the three-dimensional modeling is carried out by taking a 50MVA/110kV natural oil circulation oil-immersed power transformer as a prototype on the basis of the following assumptions:
(1) the high-low voltage winding is simplified into a cylindrical shape, so that calculation is facilitated;
(2) the insulation layer is very thin next to the winding thickness, so its thickness is neglected;
(3) the iron core and the iron yoke are simplified into cylinders;
(4) the electromagnetic relation of the transformer is mainly determined by the iron core and the winding, so the influence of a radiator and a structural component outside the oil tank is not considered.
2. Electromagnetic field calculation theory analysis of power transformer
Electromagnetic field calculation theory: the Maxwell equation system is the basis for analyzing the electromagnetic thermal field problem and describes the macroscopic properties of an electromagnetic field, and the differential form of the macroscopic properties is as follows:
in the formula: d is a potential shift; h is the magnetic field intensity; b is the magnetic flux density; e is the electric field strength; ρ is the charge density; j is the current density.
In the constitutive relation, the properties of the material are all set to be isotropic, i.e., the magnetic field permittivity, the material permeability μ, and the electrical conductivity σ are all scalar quantities, E, D, B, H being related to the properties of the material. Heat is generated by loss calculation and transformer losses are shown in figure 2.
3. Computational theory analysis of power transformer fluid and thermal field
When the mass conservation law is applied to a fluid domain of the oil-immersed power transformer, the physical meaning of the oil flow of the oil-immersed power transformer is that the increase of the transformer oil mass in an oil tank in unit time is equal to the net mass of the transformer oil flowing into the oil tank in the same time, and the differential form of the fluid flow continuous equation is
Where ρ is the fluid density in kg/m3；μx，μy，μzIs the velocity component of the velocity vector on the x, y, z axis; t is time in units of s.
If the transformer oil flows into an incompressible flow, rho is a constant number, and the continuous equation is as follows:
when the momentum equation is applied to the fluid domain of the oil-immersed power transformer, the physical meaning represented by the momentum equation is as follows: the increase of the oil flow in the transformer tank is equal to the sum of the forces borne by the transformer tank. The three components of the momentum equation can be expressed as:
in the formula: p is pressure in Pa; tau isxx、τxy、τxzIs the component of the viscous stress τ in Pa; f. ofx、fy、fzIs a component of force per unit mass.
The method can be simplified to obtain:
Sμx＝ρfx+sx
Sμy＝ρfy+sy
Sμz＝ρfz+sz
wherein S isμx、Sμy、SμzIs a generalized source term.
S can be ignored for incompressible fluidx、Sy、Sz。
The energy conservation equation can be derived from the laws of thermodynamics, which must be followed when heat exchange occurs in a fluid. When the law of conservation of energy is applied to the fluid domain of the oil-immersed power transformer, the physical meaning is as follows: the increment of the heat energy in the transformer oil tank in unit time is equal to the sum of the heat transferred by the oil flow in unit time, the work done by the force born by the transformer oil tank and the enthalpy generation amount in the transformer oil tank. The expression is as follows:
in the formula: e is the total energy of the fluid micelles.
Wherein: h is the enthalpy per unit mass; keffIs the effective heat transfer coefficient.
4. Adding a corresponding physical field based on the theoretical analysis of an electromagnetic field and fluid solid heat;
adding four physical fields of circuit, magnetic field, heat transfer and laminar flow, and coupling: the loss generated by electromagnetic coupling is coupled with a laminar flow field after being used as excitation input heat transfer field, so as to obtain the temperature field distribution of the transformer.
5. According to the actual operation condition, field-path coupling connection under different working conditions is carried out, and parameters and boundary conditions are set; the main parameters of the model are as follows: the diameter of the iron core is 600mm, the center distance of the core column is 1140mm, and the height of the window is 1525 mm. The type of the silicon steel sheet used by the transformer iron core is 30QG120, the thickness of the lamination is 0.3mm, and the lamination coefficient is 0.97. The high-voltage side winding is rated at 110kv, rated at 262.43a, and has 629 winding turns. The low-voltage side winding is rated at 10.5kv, rated at 2749.29a and has 104 winding turns.
TABLE 1 physical Properties of winding, core and Transformer oil
Solid heat transfer not only includes heat transfer between solids such as windings and iron cores, but also includes convection heat transfer of a transformer, so that a fluid domain control equation is introduced, wherein the equation is as follows:
in the formula: rho is the density of the transformer oil; cpIs the heat capacity under normal pressure;
is a velocity field; k is the heat transfer coefficient; q is an internal heat source.
The boundary conditions of solid heat transfer are set to restrict the temperature rise characteristic:
wherein q is heat flux; n is the normal vector of the outflow on the boundary.
Laminar flow: the research object is natural oil circulation oil-immersed power transformer, and its inside oil flow velocity is very little, belongs to the laminar flow model, can be similar to transformer oil flow for incompressible fluid in engineering research:
wherein: mu is the dynamic viscosity of the transformer oil; rho is the density of the transformer oil;
is the principal stress tensor.
6. Performing a multi-physical field coupling setup
And (3) carrying out coupling setting on the thermal field and the laminar flow field according to a coupling principle, adding non-isothermal laminar flow and temperature coupling, and carrying out coupling setting on the laminar flow and the heat transfer field.
7. Mesh generation and simulation time setting
And (3) carrying out mesh subdivision on the model based on a finite element method, selectively refining subdivision precision, adding coil geometric analysis and transient solution, setting simulation time and step length, simulating to obtain a temperature distribution result of the transformer, and carrying out post-processing on the result. Firstly, obtaining the temperature distribution of the hot spot iron core and the winding of the transformer under different working conditions by simulation, wherein an equivalent circuit diagram under different working conditions is shown in fig. 3, the temperature distribution of the iron core under multiple working conditions is shown in fig. 5, 6 and 7 after the simulation is completed, and the temperature distribution of the winding under multiple working conditions is shown in fig. 8, 9 and 10.
The above preferred embodiments are merely illustrative of the technical solutions of the present invention, and are not limited thereto, and it will be apparent to those skilled in the art that various changes in form, detail, and the like can be made without departing from the scope of the claims.
Claims (8)
1. A simulation method for obtaining hot spot temperatures of a power transformer under different working conditions is characterized by comprising the following steps:
s1: establishing a three-dimensional physical model of the power transformer;
s2: analyzing the electromagnetic field calculation theory of the power transformer;
s3: analyzing the calculation theory of the fluid and the thermal field of the power transformer;
s4: adding a corresponding physical field based on the theoretical analysis of an electromagnetic field and fluid solid heat;
s5: according to the actual operation condition, field-path coupling connection under different working conditions is carried out, and parameters and boundary conditions are set;
s6: performing a multi-physical field coupling setup
S7: and (4) meshing the model based on a finite element method, and simulating to obtain the temperature distribution of the power transformer and the hot spot temperature position result thereof under different working conditions.
2. The simulation method for obtaining the hot spot temperature of the power transformer under different working conditions according to claim 1, wherein the simulation method comprises the following steps: the power transformer described in S1 is a three-dimensional physical model, and when performing the coupling analysis, an important feature of the internal structure of the model is valid and invalid, i.e. some features need to be ignored according to the type of the analysis problem. Therefore, the three-dimensional modeling is carried out by taking a 50MVA/110kV natural oil circulation oil-immersed power transformer as a prototype on the basis of the following assumptions:
(1) the high-low voltage winding is simplified into a cylindrical shape, so that calculation is facilitated;
(2) the insulation layer is very thin next to the winding thickness, so its thickness is neglected;
(3) the iron core and the iron yoke are simplified into cylinders;
(4) the electromagnetic relation of the transformer is mainly determined by the iron core and the winding, so the influence of a radiator and a structural component outside the oil tank is not considered.
3. The simulation method for obtaining the hot spot temperature of the power transformer under different working conditions according to claim 2, wherein the simulation method comprises the following steps: step S2 is specifically an electromagnetic field calculation theory: the Maxwell equation system is the basis for analyzing the electromagnetic thermal field problem and describes the macroscopic properties of an electromagnetic field, and the differential form of the macroscopic properties is as follows:
in the formula: d is a potential shift; h is the magnetic field intensity; b is the magnetic flux density; e is the electric field strength; ρ is the charge density; j is the current density.
In the constitutive relation, the properties of the material are all set to be isotropic, i.e., the magnetic field permittivity, the material permeability μ, and the electrical conductivity σ are all scalar quantities, E, D, B, H being related to the properties of the material.
4. The simulation method for obtaining the hot spot temperature of the power transformer under different working conditions according to claim 3, wherein the simulation method comprises the following steps: step S3 is specifically to calculate the temperature field of the transformer based on the fluid flow continuity equation, the momentum equation, and the energy equation.
The increase of the transformer oil mass in the oil tank in unit time is equal to the net mass of the transformer oil flowing into the oil tank in the same time, and the differential form of the fluid flow continuous equation is as follows:
rho is the fluid density in kg/m3；μx，μy，μzIs the velocity component of the velocity vector on the x, y, z axis; t is time in units of s.
The increase of the oil flow in the transformer tank is equal to the sum of the forces borne by the transformer tank. The three components of the momentum equation are expressed as:
in the formula: p is pressure in Pa; tau isxx、τxy、τxzIs the component of the viscous stress τ in Pa; f. ofx、fy、fzIs a component of force per unit mass.
The energy conservation equation can be derived from the laws of thermodynamics, which must be followed when heat exchange occurs in a fluid. The increment of the heat energy in the transformer oil tank in unit time is equal to the sum of the heat transferred by the oil flow in unit time, the work done by the force born by the transformer oil tank and the enthalpy generation amount in the transformer oil tank.
Wherein: e is the total energy of the fluid micelles; h is the enthalpy per unit mass; k is a radical ofeffIs the effective heat transfer coefficient.
5. The simulation method for obtaining the hot spot temperature of the power transformer under different working conditions according to claim 4, wherein the simulation method comprises the following steps: step S4 is to add four physical fields, namely, magnetic field, circuit, heat transfer, and laminar flow, wherein the loss generated by electromagnetic coupling is coupled with the laminar flow field after being input into the heat transfer field as excitation, thereby obtaining the temperature field distribution of the transformer.
6. The simulation method for obtaining the hot spot temperature of the power transformer under different working conditions according to claim 5, wherein the simulation method comprises the following steps: step S5 is concretely, field coupling connection under different working conditions is carried out according to actual running conditions; according to the actual situation of the field operation of the transformer, model parameters and boundary conditions of each physical field are set, wherein the model parameters and the boundary conditions comprise a heat source of a three-phase iron core, a heat source of a primary winding and a secondary winding, temperature boundary conditions, the flowing speed and the flowing direction of fluid and the like.
7. The simulation method for obtaining the hot spot temperature of the power transformer under different working conditions according to claim 6, wherein the simulation method comprises the following steps: step S6 is specifically to perform coupling setting of the thermal field and the laminar flow field according to the coupling principle, and add non-isothermal laminar flow and temperature coupling.
8. The simulation method for obtaining the hot spot temperature of the power transformer under different working conditions according to claim 7, wherein the simulation method comprises the following steps: step S6 is specifically to carry out mesh subdivision on the model based on a finite element method, choose and refine subdivision precision, add coil geometric analysis and transient solution, set simulation time and step length, and obtain the temperature distribution result of the transformer through simulation.
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| CN112597628A (en) * | 2020-11-30 | 2021-04-02 | 广西电网有限责任公司电力科学研究院 | Method and system for estimating temperature rise of transformer |
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| CN112765861A (en) * | 2020-12-30 | 2021-05-07 | 广东电网有限责任公司电力科学研究院 | Method and system for acquiring temperature characteristic curve of overheating defect of high-voltage switch equipment |
| CN112765861B (en) * | 2020-12-30 | 2023-06-20 | 广东电网有限责任公司电力科学研究院 | Temperature characteristic curve acquisition method and system for overheat defect of high-voltage switch equipment |
| CN113128086A (en) * | 2021-03-22 | 2021-07-16 | 广西电网有限责任公司电力科学研究院 | Method and system for quickly estimating real-time hot spot temperature of transformer |
| CN113076572A (en) * | 2021-04-20 | 2021-07-06 | 成都国佳电气工程有限公司 | Method for acquiring temperature field of overheat fault of high-voltage switch cabinet |
| CN113076572B (en) * | 2021-04-20 | 2023-09-29 | 成都国佳电气工程有限公司 | Temperature field acquisition method for overheat fault of high-voltage switch cabinet |
| CN113739926A (en) * | 2021-07-20 | 2021-12-03 | 中车唐山机车车辆有限公司 | Method and device for detecting temperature rise fault of train electric appliance cabinet and terminal equipment |
| CN114460863A (en) * | 2022-01-17 | 2022-05-10 | 武汉魅客科技有限公司 | Information simulation device of intelligent electric cabinet of power distribution room applying digital twin technology |
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