Generator rotor temperature state monitoring method, device, equipment and medium

Abstract

The invention relates to the field of generator state monitoring, and discloses a generator rotor temperature state monitoring method, device, equipment and medium, which can obtain a global electromagnetic field finite element model and a rotor temperature field finite element model of a generator and obtain an operation parameter group related to the rotor temperature of the generator. And based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the operation parameter group and the rotor temperature, determining simulation operation data corresponding to the plurality of simulation operation conditions. Wherein the simulation operation data corresponding to each simulation operation condition comprises parameter values of the operation parameter group and a rotor temperature value. And monitoring the rotor temperature state of the generator according to the plurality of simulation operation data. According to the invention, the temperature state of the generator rotor can be effectively monitored, the monitoring modes of the temperature state of the generator rotor are enriched, and the diversification of the monitoring modes of the temperature state of the generator rotor is realized.

Description

Technical Field

[0001] The present invention relates to the field of generator condition monitoring, and particularly to a method, device, equipment and medium for monitoring the temperature state of a generator rotor. Background Art

[0002] The rotor is an important component in a generator for providing a magnetic field. During the operation of the generator, in related technologies, an excitation current can be applied to the rotor winding to establish a magnetic field.

[0003] Among them, the rotor winding generates a large amount of heat during operation, resulting in an increase in the rotor temperature. If the temperature exceeds the tolerance limit of the rotor, it will cause the aging of insulating materials and a reduction in mechanical strength, and even lead to serious consequences such as inter-turn short circuit of the winding.

[0004] However, in related technologies, generally, relevant operating parameter values of the rotor temperature are collected, and the relevant operating parameter values are input into an online calculation formula for the rotor temperature to calculate the rotor temperature. When it is determined that the rotor temperature exceeds the limit, it is determined that the rotor temperature of the generator is abnormal and an alarm is given. The monitoring method for the rotor temperature state is relatively single. Summary of the Invention

[0005] The present invention provides a method, device, equipment and medium for monitoring the temperature state of a generator rotor, so as to solve the defect of a single monitoring method for the rotor temperature state in related technologies and diversify the monitoring methods for the rotor temperature state.

[0006] In a first aspect, the present invention provides a method for monitoring the temperature state of a generator rotor, including: Obtaining a global electromagnetic field finite element model and a rotor temperature field finite element model of the generator, and obtaining an operating parameter set related to the rotor temperature of the generator; Based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the operating parameter set and the rotor temperature, determining simulation operation data corresponding to a plurality of simulated operation conditions; wherein, the simulation operation data corresponding to each simulated operation condition includes the parameter values of the operating parameter set and the rotor temperature value; Monitoring the rotor temperature state of the generator according to the parameter values of the operating parameter set and the rotor temperature value in the plurality of simulation operation data.

[0007] Optionally, the monitoring the rotor temperature state of the generator according to the parameter values of the operating parameter set and the rotor temperature value in the plurality of simulation operation data includes: During the operation of the generator, determining a target rotor temperature value through the online calculation formula of the rotor temperature of the generator; If it is determined that the target rotor temperature value is not greater than a preset rotor temperature threshold, then the rotor temperature state of the generator is monitored according to the parameter values and rotor temperature values of the operation parameter group in the multiple simulation operation data.

[0008] Optionally, the monitoring of the rotor temperature state of the generator according to the parameter values and rotor temperature values of the operation parameter group in the multiple simulation operation data includes: Obtain the target parameter values of the operation parameter group detected by a sensor; Search for target simulation operation data including the target parameter values in the multiple simulation operation data, and determine the rotor temperature value in the target simulation operation data as the standard rotor temperature value; Calculate the temperature deviation between the standard rotor temperature value and the target rotor temperature value; Judge whether the temperature deviation is greater than a preset temperature deviation threshold; If the temperature deviation is greater than the temperature deviation threshold, determine that the rotor temperature state of the generator is abnormal; If the temperature deviation is not greater than the temperature deviation threshold, determine that the rotor temperature state of the generator is normal.

[0009] Optionally, the obtaining of the operation parameter group related to the rotor temperature of the generator includes: Obtain the online calculation formula for the rotor temperature of the generator; Determine multiple operation parameters for calculating the rotor temperature in the online calculation formula for the rotor temperature; Determine the multiple operation parameters as a whole as the operation parameter group.

[0010] Optionally, the obtaining of the operation parameter group related to the rotor temperature of the generator includes: Obtain the actual operation data of the generator, where the actual operation data includes multiple operation parameters and the parameter values of the rotor temperature at multiple operation time points; Determine the correlation degree between each operation parameter and the rotor temperature according to the multiple operation parameters and the parameter values of the rotor temperature at multiple operation time points; Determine multiple target correlation degrees exceeding the preset correlation degree threshold among the correlation degrees between each operation parameter and the rotor temperature; Determine the operation parameters corresponding to each target correlation degree as a whole as the operation parameter group.

[0011] Optionally, the operation parameter group includes at least two of stator voltage, stator current, active power, reactive power, cooling water temperature, cooling water flow rate, cooling gas temperature, cooling gas flow rate, excitation voltage, and excitation current.

[0012] Optionally, determining the simulation operation data corresponding to a plurality of simulated operation conditions based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the operation parameter set, and the rotor temperature includes: Determining a corresponding solution equation based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the operation parameter set, and the rotor temperature, where the solution equation includes the operation parameter set and the rotor temperature; For any one of the simulated operation conditions, obtaining the excitation source and boundary conditions corresponding to the simulated operation condition, and determining the simulation operation data under the simulated operation condition based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the solution equation, the excitation source, and the boundary conditions; Among them, the plurality of simulated operation conditions include the normal operation common conditions, abnormal operation conditions, and various fault conditions of the generator.

[0013] In a second aspect, the present invention provides a generator rotor temperature state monitoring device, including: A first acquisition unit for acquiring the global electromagnetic field finite element model and the rotor temperature field finite element model of the generator; A second acquisition unit for acquiring an operation parameter set related to the rotor temperature of the generator; A data determination unit for determining the simulation operation data corresponding to a plurality of simulated operation conditions based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the operation parameter set, and the rotor temperature; among them, the parameter values of the operation parameter set and the rotor temperature values are included in the simulation operation data corresponding to each simulated operation condition; A state monitoring unit for monitoring the rotor temperature state of the generator according to the parameter values of the operation parameter set and the rotor temperature values in the plurality of simulation operation data.

[0014] In a third aspect, the present invention provides a computer device, including: a memory and a processor, which are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to execute the generator rotor temperature state monitoring method according to the first aspect or any corresponding embodiment thereof.

[0015] In a fourth aspect, the present invention provides a computer-readable storage medium, on which computer instructions are stored, and the computer instructions are used to cause a computer to execute the generator rotor temperature state monitoring method according to the first aspect or any corresponding embodiment thereof.

[0016] The generator rotor temperature state monitoring method, device, equipment and medium provided by the present invention can obtain the global electromagnetic field finite element model and the rotor temperature field finite element model of the generator, and obtain the operating parameter set related to the rotor temperature of the generator. Based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the operating parameter set and the rotor temperature, the simulation operation data corresponding to multiple simulated operating conditions are determined. Among them, the parameter values of the operating parameter set and the rotor temperature values are included in the simulation operation data corresponding to each simulated operating condition. The rotor temperature state of the generator is monitored according to the multiple simulation operation data. The present invention can effectively realize the monitoring of the rotor temperature state of the generator, enrich the monitoring methods of the rotor temperature state of the generator, and realize the diversification of the monitoring methods of the rotor temperature state of the generator. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1 It is a flowchart of a generator rotor temperature state monitoring method provided by an embodiment of the present invention; Figure 2 It is a three-dimensional solid model diagram of a large steam turbine rotor provided by an embodiment of the present invention; Figure 3 It is a three-dimensional solid model diagram of a large steam turbine generator rotor coil provided by an embodiment of the present invention; Figure 4 It is a schematic diagram of rotor tooth grooves, pole numbers and winding connections provided by an embodiment of the present invention; Figure 5 It is a schematic diagram of a rotor ventilation duct and a blockage point provided by an embodiment of the present invention; Figure 6 It is a flowchart of another generator rotor temperature state monitoring method provided by an embodiment of the present invention Figure 7 It is a schematic structural diagram of a generator rotor temperature state monitoring device provided by an embodiment of the present invention; Figure 8 It is a schematic structural diagram of a computer device provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts shall fall within the protection scope of the present invention.

[0020] The following will describe Figures 1 - 6 the method for monitoring the temperature state of the generator rotor of the present invention.

[0021] As Figure 1 shown, the first method for monitoring the temperature state of the generator rotor is proposed in this embodiment. This method may include the following steps: S101. Obtain the finite element model of the global electromagnetic field of the generator and the finite element model of the rotor temperature field.

[0022] Among them, the generator may be a large generator in a power plant.

[0023] Among them, the finite element model of the rotor temperature field is the finite element model of the fluid field and temperature field in the rotor region.

[0024] It should be noted that when the generator is operating normally, the calculation of its rotor temperature is related to the operating conditions and cooling conditions of the generator. This embodiment can establish the finite element model of the global electromagnetic field of the generator and the finite element model of the rotor temperature field. By calculating the excitation loss of the generator rotor, the eddy current loss of the rotor core, etc. under different operating conditions of the generator, the loss is used as the heat source of the fluid and heat transfer coupling model for calculating the rotor fluid and temperature, and the cooling medium is used as the boundary condition of the rotor fluid and heat transfer coupling model to calculate the temperature distribution of the rotor, and the online operating data of the generator rotor is used to verify the model data to ensure the correctness of the model.

[0025] Among them, the finite element model of the global electromagnetic field may be constructed in this embodiment based on Maxwell's equations, the boundary conditions of the electromagnetic field in the generator, the excitation current, the material properties, the geometric model, and the finite element method.

[0026] Among them, the finite element model of the rotor temperature field of the generator may be constructed in this embodiment based on the principles of thermodynamics and fluid mechanics, the cooling system of the generator, the fluid properties, the internal heat source distribution, the rotor geometric model, and the finite element method.

[0027] Specifically, the solution domain of the finite element model of the generator electromagnetic field includes: stator teeth, stator yoke, upper and lower stator windings, stator slot wedges, air gap, rotor core, rotor slot wedges, excitation windings, and damping windings, etc.

[0028] When solving the electromagnetic field of the generator, the following basic assumptions are made to simplify the calculation: (1) Assume that the electromagnetic field in the generator is uniformly distributed along the axial direction; (2) Without considering the end region, the current density vector J and the magnetic potential vector A have components only in the axial direction; (3) The outer edges of the iron cores of the stator and rotor of the generator A = 0; (4) The resistivity and magnetic permeability of the materials used in the generator are not affected by temperature.

[0029] In the entire field domain Ω of the generator, the magnetic potential vector A Z satisfies the following boundary value equation: .

[0030] Wherein, μ is the magnetic permeability; A Z is the component of the vector magnetic potential on the z-axis; J Z is the component of the current density in z the axis; σ is the conductivity; Γ is the first type of boundary condition.

[0031] Among them, the fluid and heat transfer coupling finite element model of the generator rotor is as Figure 2 shown. Taking a large steam turbine generator as an example, according to the symmetry of its structure, a three-dimensional solid model of the large steam turbine generator rotor is established, including the 1 / 8 circumferential structure of the rotor core and the coil straight segment models of slots 1 to 4 with half of the axial length. There are teeth on it, Outlet is the outlet, and Inlet is the inlet. As Figure 3 shown, considering that the heat of the rotor winding is mainly carried away by the cooling gas in the ventilation ducts of the winding, the model is simplified, and the temperature field is calculated by calculating the straight segment of the longest No. 4 coil. A three-dimensional solid model of the straight segment of the rotor coil including the winding copper bar, main insulation, interlayer insulation, and slot wedge is established, and it also includes inlets, outlets, adiabatic surfaces, and heat dissipation surfaces, etc.

[0032] The solid-solid contact surface and solid-fluid contact surface of the rotor are the coupled wall boundaries, and heat transfer is carried out by the three-dimensional heat transfer formula. The local fluid field and temperature field models of the generator are calculated by the finite volume method, and satisfy the mass conservation equation, momentum conservation equation, and energy conservation equation.

[0033] Specifically, the local fluid field and temperature field models of the generator rotor are calculated by the finite volume method, and satisfy the mass conservation equation, momentum conservation equation, and energy conservation equation.

[0034] Among them, the mass conservation equation is: .

[0035] In the formula, ρ is the fluid density; t is the time; V is the fluid velocity vector.

[0036] Among them, the momentum conservation equation is: .

[0037] In the formula, v r , v θ and v z are the relative velocity vectors along r , θ and z ; p is the static pressure acting on the fluid element; μ is the viscosity coefficient; S r , S θ and S z are the generalized source terms of the momentum conservation equation.

[0038] Among them, the energy conservation equation is: .

[0039] In the formula, t is the time; θ , r and z are the circumferential, radial and axial coordinate components in the solution domain under the cylindrical coordinate system; v θ , v r and v z are the components of the fluid velocity in the circumferential, radial and axial directions; υ is the kinematic viscosity; υ T is the turbulent kinematic viscosity; p is the static pressure acting on the fluid element; T is the temperature; Pr is the Prandtl number; Pr T is the turbulent Prandtl number; S T is the ratio of the heat generated by the heat source per unit volume to the specific heat capacity.

[0040] In the fluid region, the Reynolds number of the fluid Re> 2320, the rotor solution domain does not involve rotational motion, and the standard k - ε turbulence equation is selected to simulate the fluid motion in the solution domain. The fluid motion simulation equation is: .

[0041] In the formula, k is the turbulent kinetic energy; ε is the diffusion factor; ρ is the fluid density; V is the fluid velocity vector; μ t is the turbulent viscosity coefficient; G k is the turbulent production rate; G 1ε and G 2ε are constants; σ k and σ ε are the turbulent Prandtl constants.

[0042] In the fluid region, the Reynolds number of the fluid Re > 2320, the rotor solution domain does not involve rotational motion, and the standard k - ε turbulence equation is selected to simulate the fluid motion in the solution domain. The fluid motion simulation equation is: .

[0043] In the formula, k is the turbulent kinetic energy; ε is the diffusion factor; ρ is the fluid density; V is the fluid velocity vector; μ t is the turbulent viscosity coefficient; G k is the turbulent production rate; G 1ε and G 2ε are constants; σ k and σ ε are the turbulent Prandtl constants.

[0044] S102. Obtain the set of operating parameters related to the rotor temperature of the generator.

[0045] Optionally, step S102 may include: Obtain the online calculation formula for the rotor temperature of the generator; Determine multiple operating parameters for calculating the rotor temperature in the online calculation formula of the rotor temperature; Determine the multiple operating parameters as an operating parameter group as a whole.

[0046] It should be noted that the online calculation formula of the rotor temperature involves stator voltage, stator current, active power, reactive power, cooling water temperature, cooling water flow rate, cooling gas temperature, cooling gas flow rate, excitation voltage, and excitation current.

[0047] At this time, the operating parameter group includes at least two of stator voltage, stator current, active power, reactive power, cooling water temperature, cooling water flow rate, cooling gas temperature, cooling gas flow rate, excitation voltage, and excitation current.

[0048] Specifically, the rotor temperature can be the average temperature of the rotor winding. This embodiment can calculate the real-time resistance value of the rotor based on the existing online operation data such as the rotor excitation voltage and excitation current of a large generator, and according to the thermistor principle, reflect the temperature change through the calculated resistance value. Among them, the relationship between the average temperature of the rotor winding and the winding resistance value is:

[0049] Among them, is the average temperature of the rotor winding, is the resistance value of the rotor winding, the resistance at the current temperature, is the current temperature.

[0050] Among them, this embodiment can obtain the stator voltage, stator current, active power, reactive power, cooling water temperature, cooling water flow rate, cooling gas temperature, cooling gas flow rate, excitation voltage, and excitation current from the generator online operation data to calculate , , and , and then the average temperature of the rotor winding can be calculated.

[0051] Optionally, step S102 may include: Obtain the real operation data of the generator, where the real operation data includes multiple operating parameters and the parameter values of the rotor temperature at multiple operation time points; According to the multiple operating parameters and the parameter values of the rotor temperature at multiple operation time points, determine the correlation degree between each operating parameter and the rotor temperature; Among the correlation degrees between each operating parameter and the rotor temperature, determine multiple target correlation degrees that exceed the preset correlation degree threshold; Determine the operating parameters corresponding to each target correlation degree as an operating parameter group as a whole.

[0052] Specifically, the actual operation data of the generator includes the operation data at multiple operation time points, and the operation data at each operation time point includes the parameter values of multiple operation parameters and the rotor temperature value.

[0053] Among them, the operation time point can be a moment or a period with a specific duration (such as 10 seconds or 20 seconds).

[0054] Specifically, when the operation time point is a moment, for any operation parameter, in this embodiment, the parameter value of the operation parameter at a certain operation time point during the operation of the generator can be collected as the parameter value of the operation parameter at this operation time point.

[0055] Specifically, when the operation time point is a specific duration, in this embodiment, the average parameter value of the operation parameter within this specific duration can be determined as the parameter value of the operation parameter at this operation time point, or the parameter value of the operation parameter can be collected every this specific duration, and the collected parameter value can be used as the parameter value of the operation parameter at this operation time point.

[0056] It can be understood that in this embodiment, the parameter values of each operation parameter collected and determined at multiple operation time points of the generator can be taken as a whole as the above actual operation data.

[0057] Among them, the preset correlation threshold can be set by technicians according to actual needs. For example, it can be set to 0.9, and the specific size of this embodiment is not limited.

[0058] Specifically, in this embodiment, according to the parameter values of each operation parameter and the rotor temperature value in the above actual operation data, and according to the calculation formula of the Pearson correlation coefficient or the Spearman correlation coefficient, the correlation between each operation parameter and the rotor temperature can be calculated. Among the calculated correlations, the correlations greater than the preset correlation threshold are determined as the target correlations. Then, in this embodiment, all the operation parameters with the correlation with the rotor temperature being the target correlation can be determined as a group of operation parameters as a whole.

[0059] It should be noted that as Figure 1 shown, in this embodiment, step S101 can be executed first, and then step S102 can be executed. Of course, in this embodiment, step S102 can also be executed first, and then step S101 can be executed.

[0060] S103. Based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the group of operation parameters, and the rotor temperature, determine the simulation operation data corresponding to multiple simulated operation conditions; among them, the simulation operation data corresponding to each simulated operation condition includes the parameter values of the group of operation parameters and the rotor temperature value.

[0061] Specifically, the simulated operating conditions can correspond to the actual operating conditions of the generator. In this embodiment, the generator can be simulated and operated, and the simulation operation data of the generator can be collected under the simulated operating conditions.

[0062] Specifically, in this embodiment, the generator can be simulated and operated under various simulated operating conditions, and the simulation operation data of the generator under each simulated operating condition can be collected and recorded respectively.

[0063] Optionally, step S103 may include: Based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the operating parameter set, and the rotor temperature, determine the corresponding solution equation, which includes the operating parameter set and the rotor temperature; For any simulated operating condition, obtain the excitation source and boundary conditions corresponding to the simulated operating condition, and based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the solution equation, the excitation source, and the boundary conditions, determine the simulation operation data under the simulated operating condition; Among them, the multiple simulated operating conditions include the normal operating common conditions, abnormal operating conditions, and various fault conditions of the generator.

[0064] It should be noted that in this embodiment, certain conditions can be defined in the finite element analysis software to reflect different simulated operating conditions. Specifically, in this embodiment, in the finite element analysis software, the excitation source and boundary conditions can be assigned according to the simulated operating conditions to reflect the simulated operating conditions.

[0065] Among them, the excitation sources in the global electromagnetic field finite element model include voltage, current, etc., and the excitation sources in the rotor temperature field finite element model include the magnitude of the heat source, etc. In this embodiment, the excitation source and boundary conditions can be assigned according to different simulated operating conditions, and in the finite element analysis software, the assigned excitation source, boundary conditions, the established global electromagnetic field finite element model, and the rotor temperature field finite element model are combined for simulation analysis to determine the corresponding simulation operation data.

[0066] Among them, the simulation operation data under any simulated operating condition can include the parameter values of each operating parameter in the operating parameter set and the rotor temperature at multiple simulation operation time points during the process of the simulated operating condition.

[0067] Specifically, in this embodiment, based on the established global electromagnetic field finite element model and rotor temperature field finite element model, the calculated values of the rotor temperature under faults such as inter-turn short circuit of the generator rotor and blockage of the rotor air duct can be further calculated, and the corresponding relationship between the rotor temperature of the generator and parameters such as the excitation voltage, current, cooling gas temperature, flow rate, and air pressure under different operating conditions of the generator can be established.

[0068] Specifically, this embodiment can establish asFigure 4 The shown generator rotor inter-turn short circuit model numbers the rotor teeth and slots (such as 1, 3, 5, 7, 9, and 11 shown in Figure 4 ), and the magnetic poles (such as A, B, C, and D shown in Figure 4 ), as well as the connection method of each turn of the winding, and the current. Calculate the rotor losses and temperatures under different inter-turn short circuits of the winding and different numbers of short circuits. This embodiment can be based on the rotor ventilation ducts and blockage points shown in Figure 5 to calculate the temperatures of the rotor under different blockage point positions and numbers of blockages (such as blockage point 1 and blockage point 2 in Figure 5 ). Figure 5 The shown rotor model includes an air outlet, windings, a rotor body, radial ducts, and auxiliary slots, and also shows the rotor rotation direction. This embodiment can establish the corresponding relationship between the rotor temperature and different operating conditions, inter-turn short circuit faults, duct blockage faults, etc.

[0069] S104. Monitor the rotor temperature state of the generator according to the parameter values of the operating parameter groups and the rotor temperature values in multiple simulation operation data.

[0070] Specifically, this embodiment can monitor the rotor temperature state of the generator during operation based on all simulation operation data.

[0071] Optionally, step S104 may include: During the operation of the generator, determine the target rotor temperature value through the online calculation formula of the rotor temperature of the generator; If it is determined that the target rotor temperature value is not greater than the preset rotor temperature threshold, then monitor the rotor temperature state of the generator according to the parameter values of the operating parameter groups and the rotor temperature values in multiple simulation operation data.

[0072] Among them, the rotor temperature threshold can be set by technicians according to the actual situation, and this embodiment does not limit it.

[0073] Specifically, this embodiment can, during the operation of the generator, monitor the target rotor temperature value in real time through the online calculation formula of the rotor temperature of the generator, and compare the monitored target rotor temperature value with the rotor temperature threshold.

[0074] Among them, when it is determined that the target rotor temperature value is greater than the rotor temperature threshold, it can be directly determined that the rotor temperature state of the engine is abnormal. When it is determined that the target rotor temperature value is not greater than the rotor temperature threshold, this embodiment can monitor the rotor temperature state of the generator according to the simulation operation data.

[0075] Optionally, monitoring the rotor temperature state of the generator according to the parameter values of the operation parameter group and the rotor temperature value in multiple simulation operation data includes: Obtain the target parameter values of the operation parameter group detected by the sensor; Search for the target simulation operation data including the target parameter values in the multiple simulation operation data, and determine the rotor temperature value in the target simulation operation data as the standard rotor temperature value; Calculate the temperature deviation between the standard rotor temperature value and the target rotor temperature value; Judge whether the temperature deviation is greater than the preset temperature deviation threshold; If the temperature deviation is greater than the temperature deviation threshold, determine that the rotor temperature state of the generator is abnormal; If the temperature deviation is not greater than the temperature deviation threshold, determine that the rotor temperature state of the generator is normal.

[0076] Specifically, the target parameter values of the operation parameter group may include the parameter values of each operation parameter in the operation parameter group.

[0077] Among them, the temperature deviation threshold can be set by technicians according to the actual situation, and this embodiment does not make a limitation.

[0078] Specifically, this embodiment can obtain the target parameter values of the operation parameter group detected by the sensor, and judge whether the rotor temperature state of the generator is abnormal based on the target parameter values, multiple simulation operation data and the target rotor temperature value.

[0079] Specifically, this embodiment can search for the simulation operation data including the target parameter values in all the simulation operation data and use it as the target simulation operation data. Then, the rotor temperature value in the target simulation operation data can be determined as the standard rotor temperature value, and the absolute value of the difference between the standard rotor temperature value and the target rotor temperature value, that is, the temperature deviation, can be calculated, and whether the rotor temperature state of the generator is abnormal can be judged according to the temperature deviation.

[0080] Among them, this embodiment can determine that the rotor temperature state of the generator is abnormal when the temperature deviation is greater than the temperature deviation threshold. When the temperature deviation is not greater than the temperature deviation threshold, it is determined that the rotor temperature state of the generator is normal.

[0081] It can be understood that this embodiment can judge whether the rotor temperature calculated online during the operation of the generator exceeds the generator temperature warning value. If it exceeds, it is determined as a generator rotor temperature fault. If it does not exceed, the generator rotor temperature can be determined whether it is faulty according to the simulation operation data, the target parameter value and the rotor temperature calculated online.

[0082] The generator rotor temperature state monitoring method proposed in this embodiment can obtain the finite element model of the global electromagnetic field of the generator and the finite element model of the rotor temperature field, as well as obtain the operating parameter set related to the rotor temperature of the generator. Based on the finite element model of the global electromagnetic field, the finite element model of the rotor temperature field, the operating parameter set, and the rotor temperature, the simulation operation data corresponding to multiple simulated operation conditions are determined. Among them, the parameter values of the operating parameter set and the rotor temperature values are included in the simulation operation data corresponding to each simulated operation condition. The rotor temperature state of the generator is monitored according to the multiple simulation operation data. This embodiment can effectively realize the monitoring of the rotor temperature state of the generator, enrich the monitoring methods of the rotor temperature state of the generator, and realize the diversification of the monitoring methods of the rotor temperature state of the generator.

[0083] It should be noted that the rotor is an important component that provides the main magnetic field for a large generator. When the generator is running, an excitation current is applied to the rotor winding to establish a magnetic field. The rotor winding with the excitation current generates a large amount of heat, which will cause the temperature to rise. If the temperature exceeds the tolerance limit of the insulating material, it will cause the insulating material to age, the mechanical strength to decrease, and even lead to serious consequences such as inter-turn short circuit of the winding. In addition, during the operation of the generator, the rotor is affected by many factors such as thermal stress, electromagnetic force, centrifugal force, and insulation aging, and is prone to inter-turn short circuit of the rotor winding and blockage of the air duct, which are also common electrical and mechanical faults of the generator. At the same time, the overheating of the rotor coil caused by the blockage of the rotor winding air duct further causes damage to the inter-turn insulation and results in an inter-turn short circuit fault. The long-term operation of the generator with problems may cause irreversible thermal damage to the rotor, trigger severe vibration of the unit, and seriously endanger the normal operation and service life of the unit.

[0084] Therefore, it is very necessary to perform on-line monitoring of the generator rotor temperature. By real-time monitoring the rotor temperature, temperature anomalies can be detected in a timely manner, equipment damage and safety accidents caused by overheating can be avoided, and the safe operation of the generator can be guaranteed. The on-line monitoring of the generator rotor temperature can also improve the maintenance efficiency and management level. Through the monitoring system, the rotor temperature data can be collected and analyzed in real time, temperature anomalies can be detected and alarmed in a timely manner, and the errors and inconveniences of manual regular data collection can be reduced.

[0085] However, the rotor temperature rise test method applied in the related technology can only measure the average temperature rise of the motor rotor coil, and cannot reflect the temperature rise distribution and hot spot conditions. Even if its average temperature rise meets the requirements, there may very likely be hidden dangers such as local overheating points, and the harmful local high temperature and temperature distribution conditions cannot be known, which is not suitable for the requirements of the safe operation of the generator and the full play of the unit's potential, and thus cannot accurately reflect the safe operation status of the generator.

[0086] In the related art, the on-line monitoring means for large generator rotors can only reflect the current values of monitoring components, and the early warning function is triggered only when the rotor temperature exceeds the limit. If there is a rotor temperature fault, it can only be detected when the fault is very serious, making it difficult to achieve early warning of potential hazards and avoid the expansion of accidents.

[0087] As Figure 6 shown, in this embodiment, stator voltage, stator current, active power, reactive power, cooling water temperature, cooling water flow rate, cooling gas temperature, cooling gas flow rate, excitation voltage, and excitation current can be extracted from the on-line operation data of the generator, the on-line resistance value of the rotor can be calculated, and then the rotor temperature can be calculated. Figure 6 in is the average temperature of the rotor winding, is the resistance value of the rotor winding, the resistance at the current temperature, is the current temperature.

[0088] As Figure 6 shown, this embodiment can establish a generator rotor temperature model. Specifically, this embodiment can establish a global electromagnetic field finite element model and a rotor temperature field finite element model, combine various operating conditions of the generator, perform multi-physical field calculations on the generator rotor, and establish the corresponding relationship between the rotor temperature and various operating conditions of the generator. This embodiment can judge whether the rotor temperature calculated online during the operation of the generator exceeds the early warning temperature. If it exceeds, it is determined that there is a generator rotor temperature fault. If it does not exceed, the standard rotor temperature can be determined according to the simulation operation data and the target parameter values, that is, the temperature calculation value of the rotor temperature model. Calculate the absolute value of the temperature difference between the standard rotor temperature and the rotor temperature calculated online. Judge whether the absolute value of the temperature difference is greater than or equal to the early warning difference. If so, it can be determined that there is a generator rotor temperature fault. Otherwise, it is determined that the generator rotor temperature is normal.

[0089] This embodiment can address the defects existing in the existing on-line monitoring technology for large generator rotor temperatures, can reflect the current average temperature state of the generator rotor in real time, and can also judge and give early warnings for early faults such as increased generator rotor temperature caused by rotor inter-turn short circuits and air duct blockages. It is difficult for operators and management personnel to make comprehensive analyses in a short time to avoid the expansion of accidents and ensure the safe operation of the unit.

[0090] The calculation and monitoring of the large generator rotor temperature in this embodiment are based on the technology of on-line monitoring of large generator rotor temperatures in the related art, which belongs to indirect temperature measurement, does not require additional sensors, and does not affect the normal operation of the generator.

[0091] This embodiment can consider the rotor temperature changes under various operating conditions of the generator and faults such as inter-turn short circuit of the rotor and blockage of the air duct, providing a relatively comprehensive basis for the monitoring of the rotor temperature and the diagnosis during faults. This embodiment can also give early warnings for faults such as inter-turn short circuit of the rotor and blockage of the air duct that cause the rotor temperature to rise, enabling operators and managers to make comprehensive analyses in a short time.

[0092] The online monitoring technology for the thermal state of the generator rotor in this embodiment can combine the current value of the rotor temperature detected and calculated by the existing monitoring components in the generator and functions such as parameter over-limit alarm, and propose a function of comparing and judging with the standard value calculated by the rotor temperature model under the current operating condition of the generator. The standard value calculated by the rotor temperature model is the temperature calculation value under different operating conditions and typical faults such as inter-turn short circuit of the rotor and blockage of the air duct obtained by establishing finite element numerical models of the generator's electromagnetics, fluid, temperature, etc. It covers a wide range of operating conditions and has sufficient basis for temperature judgment. This embodiment can judge whether there is a temperature fault in the generator by comparing the difference between the calculated rotor temperature and the running value with the threshold under this operating condition, avoiding the situation that when the generator rotor has faults such as inter-turn short circuit and air duct blockage when the generator is not running at full load, the rotor temperature does not exceed the limit and no alarm is issued, providing early warning for the generator temperature fault to prevent the occurrence or expansion of accidents.

[0093] As Figure 7 shown, this embodiment proposes a monitoring device for the temperature state of the generator rotor, which may include: A first acquisition unit 701, configured to acquire the global electromagnetic field finite element model and the rotor temperature field finite element model of the generator; A second acquisition unit 702, configured to acquire an operating parameter group related to the rotor temperature of the generator; A data determination unit 703, configured to determine simulation operation data corresponding to a plurality of simulated operation conditions based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the operating parameter group, and the rotor temperature; wherein, the simulation operation data corresponding to each simulated operation condition includes the parameter values of the operating parameter group and the rotor temperature value; A state monitoring unit 704, configured to monitor the temperature state of the generator rotor according to the parameter values of the operating parameter group and the rotor temperature value in the plurality of simulation operation data.

[0094] It should be noted that the processing processes of the first acquisition unit 701, the second acquisition unit 702, the data determination unit 703, and the state monitoring unit 704 and the beneficial effects brought thereby can respectively refer to Figure 1 the steps S101 to S104 in

[0095] Optionally, the state monitoring unit 704 is further configured to: During the operation of the generator, the target rotor temperature value is determined through the online calculation formula of the rotor temperature of the generator; If it is determined that the target rotor temperature value is not greater than the preset rotor temperature threshold, then the rotor temperature state of the generator is monitored according to the parameter values and rotor temperature values of the operation parameter groups in multiple simulation operation data.

[0096] Optionally, the state monitoring unit 704 is further configured to: Obtain the target parameter values of the operation parameter groups detected by the sensors; Search for the target simulation operation data including the target parameter values in multiple simulation operation data, and determine the rotor temperature value in the target simulation operation data as the standard rotor temperature value; Calculate the temperature deviation between the standard rotor temperature value and the target rotor temperature value; Determine whether the temperature deviation is greater than the preset temperature deviation threshold; If the temperature deviation is greater than the temperature deviation threshold, it is determined that the rotor temperature state of the generator is abnormal; If the temperature deviation is not greater than the temperature deviation threshold, it is determined that the rotor temperature state of the generator is normal.

[0097] Optionally, the second acquisition unit 702 is further configured to: Obtain the online calculation formula of the rotor temperature of the generator; Determine multiple operation parameters for calculating the rotor temperature in the online calculation formula of the rotor temperature; Determine the multiple operation parameters as an operation parameter group as a whole.

[0098] Optionally, the second acquisition unit 702 is further configured to: Obtain the actual operation data of the generator, where the actual operation data includes multiple operation parameters and the parameter values of the rotor temperature at multiple operation time points; Determine the correlation degree between each operation parameter and the rotor temperature according to the multiple operation parameters and the parameter values of the rotor temperature at multiple operation time points; Among the correlation degrees between each operation parameter and the rotor temperature, determine multiple target correlation degrees that exceed the preset correlation degree threshold; Determine the operation parameters corresponding to each target correlation degree as an operation parameter group as a whole.

[0099] Optionally, the operation parameter group includes at least two of stator voltage, stator current, active power, reactive power, cooling water temperature, cooling water flow rate, cooling gas temperature, cooling gas flow rate, excitation voltage, and excitation current.

[0100] Optionally, the data determination unit 703 is further configured to: Based on the finite element model of the global electromagnetic field, the finite element model of the rotor temperature field, the set of operating parameters, and the rotor temperature, the corresponding solution equations are determined, and the solution equations include the set of operating parameters and the rotor temperature; For any simulated operating condition, the excitation source and boundary conditions corresponding to the simulated operating condition are obtained. Based on the finite element model of the global electromagnetic field, the finite element model of the rotor temperature field, the solution equations, the excitation source, and the boundary conditions, the simulation operation data under the simulated operating condition are determined; Among them, multiple simulated operating conditions include the normal operating common conditions, abnormal operating conditions, and various fault conditions of the generator.

[0101] The generator rotor temperature state monitoring device proposed in this embodiment can obtain the finite element model of the global electromagnetic field of the generator and the finite element model of the rotor temperature field, and obtain the set of operating parameters related to the rotor temperature of the generator. Based on the finite element model of the global electromagnetic field, the finite element model of the rotor temperature field, the set of operating parameters, and the rotor temperature, the simulation operation data corresponding to multiple simulated operating conditions are determined. Among them, the simulation operation data corresponding to each simulated operating condition includes the parameter values of the set of operating parameters and the rotor temperature value. According to multiple simulation operation data, the rotor temperature state of the generator is monitored. This embodiment can effectively realize the monitoring of the rotor temperature state of the generator, enrich the monitoring methods of the rotor temperature state of the generator, and realize the diversification of the monitoring methods of the rotor temperature state of the generator.

[0102] The generator rotor temperature state monitoring device in this embodiment is presented in the form of functional units. Here, the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and a memory that execute one or more software or fixed programs, and / or other devices that can provide the above functions.

[0103] The embodiment of the present invention also provides a computer device having the above Figure 7 shown generator rotor temperature state monitoring device.

[0104] Please refer to Figure 8, A schematic structural diagram of a computer device provided by an alternative embodiment of the present invention. The computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Each component communicates with each other using different buses and can be installed on a common motherboard or installed in other ways as needed. The processor can process instructions executed within the computer device, including instructions stored in the memory or on the memory to display graphical information of the GUI on an external input / output device (such as a display device coupled to the interface). In some alternative embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (such as an array of servers, a set of blade servers, or a multi-processor system). Figure 8 Taking one processor 10 as an example.

[0105] The processor 10 can be a central processing unit, a network processor, or a combination thereof. Among them, the processor 10 can further include a hardware chip. The above-mentioned hardware chip can be an application-specific integrated circuit, a programmable logic device, or a combination thereof. The above-mentioned programmable logic device can be a complex programmable logic device, a field programmable gate array, a general array logic, or any combination thereof.

[0106] Among them, the memory 20 stores instructions executable by at least one processor 10, so that at least one processor 10 executes the method shown in the above embodiment.

[0107] The memory 20 can include a program storage area and a data storage area. Among them, the program storage area can store an operating system and application programs required for at least one function. The data storage area can store data created according to the use of the computer device. In addition, the memory 20 can include a high-speed random access memory, and can also include a non-transitory memory, such as at least one disk storage device, a flash memory device, or other non-transitory solid-state storage devices. In some alternative embodiments, the memory 20 can optionally include a memory remotely set relative to the processor 10, and these remote memories can be connected to the computer device through a network. Examples of the above-mentioned network include but are not limited to the Internet, an enterprise intranet, a local area network, a mobile communication network, and combinations thereof.

[0108] The memory 20 can include a volatile memory, such as a random access memory. The memory can also include a non-volatile memory, such as a flash memory, a hard disk, or a solid-state drive. The memory 20 can also include a combination of the above types of memories.

[0109] The computer device further includes a communication interface 30 for the computer device to communicate with other devices or communication networks.

[0110] Embodiments of the present invention also provide a computer-readable storage medium. The method according to the embodiments of the present invention can be implemented in hardware, firmware, or be implemented as computer code that can be recorded on a storage medium, or be implemented as computer code that is originally stored in a remote storage medium or a non-transitory machine-readable storage medium and downloaded through a network and will be stored in a local storage medium, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory, a random access memory, a flash memory, a hard disk, or a solid-state drive, etc.; further, the storage medium can also include a combination of the above-mentioned types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by the computer, the processor, or the hardware, the method shown in the above embodiments is implemented.

[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for monitoring the temperature state of a generator rotor, characterized in that: include: Acquire a global electromagnetic field finite element model and a rotor temperature field finite element model of the generator, and acquire an operating parameter group related to the rotor temperature of the generator; Determine the simulation operation data corresponding to a plurality of simulated operation conditions based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the operation parameter group and the rotor temperature; wherein the simulation operation data corresponding to each of the simulated operation conditions includes the parameter value of the operation parameter group and the rotor temperature value; The rotor temperature state of the generator is monitored according to the parameter values ​​of the operating parameter group and the rotor temperature value in the plurality of simulation operating data.

2. The method according to claim 1, characterized in that The monitoring of the rotor temperature state of the generator according to the parameter values ​​of the operating parameter group and the rotor temperature value in the plurality of simulation operating data comprises: When the generator is in operation, a target rotor temperature value is determined by an online calculation formula of the rotor temperature of the generator; If it is determined that the target rotor temperature value is not greater than a preset rotor temperature threshold, the rotor temperature state of the generator is monitored according to the parameter values ​​of the operating parameter group in the plurality of simulation operating data and the rotor temperature value.

3. The method according to claim 2, characterized in that The step of monitoring the rotor temperature state of the generator according to the parameter values ​​of the operating parameter group and the rotor temperature value in the plurality of simulation operating data comprises: Acquiring a target parameter value of the operating parameter group detected by a sensor; Searching for target simulation operation data including the target parameter value among the plurality of simulation operation data, and determining the rotor temperature value in the target simulation operation data as the standard rotor temperature value; Calculating a temperature deviation between the standard rotor temperature value and the target rotor temperature value; Determining whether the temperature deviation is greater than a preset temperature deviation threshold; If the temperature deviation is greater than the temperature deviation threshold, determining that the rotor temperature state of the generator is abnormal; If the temperature deviation is not greater than the temperature deviation threshold, it is determined that the rotor temperature state of the generator is normal.

4. The method according to claim 1, characterized in that: The obtaining of an operating parameter group related to the rotor temperature of the generator includes: Obtaining an online calculation formula for the rotor temperature of the generator; Determining a plurality of operating parameters for calculating the rotor temperature in the rotor temperature online calculation formula; The plurality of operating parameters are collectively determined as the operating parameter group.

5. The method according to claim 1, characterized in that The obtaining of an operating parameter group related to the rotor temperature of the generator includes: Acquiring real operating data of the generator, wherein the real operating data includes parameter values ​​of multiple operating parameters and rotor temperature at multiple operating time points; Determining the correlation between each of the operating parameters and the rotor temperature according to the parameter values ​​of the multiple operating parameters and the rotor temperature at multiple operating time points; Among the correlations between each of the operating parameters and the rotor temperature, determining a plurality of target correlations exceeding the preset correlation threshold; The operating parameters corresponding to each of the target relevances are collectively determined as the operating parameter group.

6. The method according to claim 1, characterized in that The operating parameter group includes at least two of stator voltage, stator current, active power, reactive power, cooling water temperature, cooling water flow, cooling gas temperature, cooling gas flow, excitation voltage and excitation current.

7. The method according to claim 1, characterized in that The determining of simulation operation data corresponding to a plurality of simulated operation conditions based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the operation parameter group and the rotor temperature comprises: Determine a corresponding solution equation based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the operating parameter group and the rotor temperature, wherein the solution equation includes the operating parameter group and the rotor temperature; For any of the simulated operating conditions, obtaining the excitation source and boundary conditions corresponding to the simulated operating condition, and determining the simulation operating data under the simulated operating condition based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the solution equation, the excitation source and the boundary conditions; The multiple simulated operating conditions include common operating conditions, unusual operating conditions and various fault conditions of the normal operation of the generator.

8. A generator rotor temperature status monitoring device, characterized in that: include: A first acquisition unit is used to acquire a global electromagnetic field finite element model and a rotor temperature field finite element model of the generator; A second acquisition unit, configured to acquire an operating parameter group related to the rotor temperature of the generator; A data determination unit, configured to determine simulation operation data corresponding to a plurality of simulated operation conditions based on the global electromagnetic field finite element model, the rotor temperature field finite element model, the operation parameter group and the rotor temperature; wherein the simulation operation data corresponding to each of the simulated operation conditions includes parameter values ​​of the operation parameter group and the rotor temperature value; The state monitoring unit is used to monitor the rotor temperature state of the generator according to the parameter values ​​of the operation parameter group and the rotor temperature value in the plurality of simulation operation data.

9. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the generator rotor temperature status monitoring method according to any one of claims 1 to 7 by executing the computer instructions.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the generator rotor temperature state monitoring method according to any one of claims 1 to 7.

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