CN115065304A - Method, device, equipment and medium for estimating temperature of motor stator - Google Patents

Abstract

The invention provides a method for estimating the temperature of a motor stator, which comprises the following steps: acquiring working data of the motor, wherein the working data comprises rotating speed data, three-phase current data, cooling water inlet temperature data, cooling water outlet temperature data and cooling water flow data; processing the three-phase current data to obtain copper loss heating power data of the stator winding; processing the rotational speed data and the three-phase current data to obtain iron loss heating power data of the stator core; processing the cooling water inlet temperature data, the cooling water outlet temperature data and the cooling water flow data to obtain heat dissipation power data of the cooling water flow under forced convection; and processing the copper loss heating power data, the iron loss heating power data and the heat dissipation power data to obtain the temperature data of the motor stator. The estimation method for the temperature of the motor stator disclosed by the invention can estimate the actual temperature of the motor, and has higher accuracy.

Description

A method, device, equipment and medium for estimating stator temperature of a motor

technical field

The present invention relates to the technical field of motors, and in particular, to a method, device, equipment and medium for estimating the temperature of a motor stator.

Background technique

Permanent magnet synchronous motors are widely used in electric vehicles because of their advantages of high power density, high efficiency, low speed and high torque, high speed and constant power and wide speed regulation. During the working process of the motor, the internal temperature needs to be controlled to prevent the motor from being damaged due to excessive temperature. Due to the limited space in the stator iron core slot of the motor, the temperature sensor cannot be arranged in the stator iron core slot. When the temperature sensor is located in other places, there is a large deviation between the measured temperature and the actual temperature, and it cannot be guaranteed that the indicated temperature can be It truly reflects the actual temperature of the motor.

SUMMARY OF THE INVENTION

In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a method, device, equipment and medium for estimating the stator temperature of a motor. The present invention can estimate the actual temperature of the motor with high accuracy.

In order to achieve the above object and other related objects, the present invention provides a method for estimating the stator temperature of a motor, including:

Obtain the working data of the motor, the working data includes rotational speed data, three-phase current data, cooling water inlet temperature data, cooling water outlet temperature data and cooling water flow data;

processing the three-phase current data to obtain the copper loss heating power data of the stator winding;

Process the rotational speed data and the three-phase current data to obtain the iron loss heating power data of the stator core;

The cooling water inlet temperature data, the cooling water outlet temperature data and the cooling water flow data are processed to obtain the cooling power data of the cooling water flow under forced convection;

The copper loss heating power data, the iron loss heating power data and the heat dissipation power data are processed to obtain motor stator temperature data.

其中，In an embodiment of the present invention, the copper loss heating power data _qcu is expressed as

in,

I _peak represents the peak current data in the three-phase current data,

R _w (T) represents the resistance value when the temperature of the stator winding of a certain phase is T.

In an embodiment of the present invention, the R _w (T) is expressed as R _w (T)=R(T ₀ )*(1+α*(TT ₀ )), wherein,

R(T ₀ ) represents the resistance value of the stator winding of a certain phase when the temperature is T ₀ ,

T ₀ represents the preset temperature,

α represents a correction coefficient.

其中，In an embodiment of the present invention, the iron loss heating power data qf _e of the stator core is expressed as

in,

k ₁ , k ₂ represent undetermined coefficients,

w represents the rotational speed data.

In an embodiment of the present invention, the motor stator temperature data includes motor stator winding temperature data, motor stator iron core temperature data, and motor cooling water jacket temperature data.

In an embodiment of the present invention, the relationship between the motor stator winding temperature data T _w , the motor stator iron core temperature data T _m and the motor cooling water jacket temperature data T _s is expressed as

其中，

in,

k represents the kth sampling period.

T represents the sampling period.

C ₁ represents the equivalent heat capacity of the stator winding.

C ₂ Equivalent heat capacity of the stator core.

C3 represents the equivalent heat capacity _of the cooling water jacket.

R _wm represents the equivalent thermal resistance of the stator winding to the slots of the stator core.

R _ms represents the equivalent thermal resistance of the stator core to the cooling water jacket.

q _cs represents the cooling power data of the cooling system.

其中，In an embodiment of the present invention, the relationship between the motor stator winding temperature data T _w , the motor stator iron core temperature data T _m and the motor cooling water jacket temperature data T _s is expressed as

in,

L ^-1 represents the inverse Laplace transform symbol,

s is the Laplace variable,

I represents the identity matrix.

The present invention also provides a device for estimating the temperature of the motor stator, comprising:

a data acquisition module for acquiring the working data of the motor, the working data including rotational speed data, three-phase current data, cooling water inlet temperature data, cooling water outlet temperature data and cooling water flow data;

The copper loss heating processing module is used to process the three-phase current data to obtain the copper loss heating power data of the stator winding;

an iron loss heating processing module, configured to process the rotational speed data and the three-phase current data to obtain iron loss heating power data of the stator core;

A cooling power processing module for processing the cooling water inlet temperature data, the cooling water outlet temperature data and the cooling water flow data to obtain cooling power data of cooling water flow under forced convection; and

The stator temperature estimation module is configured to process the copper loss heating power data, the iron loss heating power data and the heat dissipation power data to obtain motor stator temperature data.

The present invention also provides a computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, the processor implementing the computer program to achieve the temperature of the motor stator steps of the estimation method.

The present invention also provides a computer-readable storage medium, where the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, implements the steps of the method for estimating the stator temperature of the motor.

As described above, the present invention provides a method, device, equipment and medium for estimating the temperature of the motor stator, which can accurately estimate the temperature data of the motor stator windings in the motor stator temperature data, the motor stator winding temperature data, and the motor based on the cooling power data of the cooling water flow under forced convection The temperature data of the stator iron core and the temperature data of the motor cooling water jacket can be used for the protection of the motor and ensure the reliable, safe and stable operation of the motor.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without any creative effort.

FIG. 1 shows a flow chart of a method for estimating the stator temperature of a motor according to the present invention.

FIG. 2 is a schematic diagram showing the use of a method for estimating the stator temperature of a motor according to the present invention.

FIG. 3 is a schematic structural diagram of a device for estimating the stator temperature of a motor according to the present invention.

FIG. 4 is a schematic diagram showing a use state of a device for estimating the stator temperature of a motor according to the present invention.

FIG. 5 is a schematic structural diagram of a computer device in an embodiment of the present invention.

FIG. 6 is another schematic structural diagram of a computer device in an embodiment of the present invention.

Component label description:

10. Data acquisition module; 20. Copper loss heating processing module; 30. Cooling power processing module; 40. Cooling power processing module; 50. Stator temperature estimation module.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

See Figures 1-6. It should be noted that the drawings provided in this embodiment are only to illustrate the basic concept of the present invention in a schematic way, so the drawings only show the components related to the present invention rather than the number, shape and the number of components in actual implementation. For dimension drawing, the type, quantity and proportion of each component can be changed at will in actual implementation, and the component layout may also be more complicated.

Referring to FIG. 1 , a method for estimating the stator temperature of a motor provided by an embodiment of the present invention can be applied to a motor of a vehicle and the like, and can be used to estimate the temperature data related to the stator winding of the motor. Due to the limited space inside the motor, the temperature sensor cannot be arranged in the stator core slot, so the temperature sensor can only be arranged on the exposed stator winding at the end of the motor, or on the busbar connecting the three-phase windings of the stator outside. Because the heating conditions and heat dissipation conditions of the stator winding and the end winding in the stator core slot are very different, the measured temperature data of the stator winding of the motor deviates greatly from the real temperature data. In order to accurately obtain the relevant temperature data of the stator winding of the motor, the measured rotational speed data, three-phase current data, cooling water inlet temperature data, cooling water outlet temperature data, and cooling water flow data can be processed to The relevant temperature data of the stator windings of the motor are estimated. The estimation method of the motor stator temperature can include the following steps:

Step S10, obtaining the working data of the motor, the working data includes rotational speed data, three-phase current data, cooling water inlet temperature data, cooling water outlet temperature data and cooling water flow data.

In an embodiment of the present invention, the working data of the motor may be obtained first, and the working data of the motor may include the rotational speed data of the motor, the three-phase current data of the motor, the temperature data of the cooling water inlet of the cooling system, the cooling water of the cooling system Water outlet temperature data and cooling water flow data of the cooling system. Among them, the speed data of the motor can be measured by the speed sensor, but not limited to this, it can also be measured by the magnetoelectric speed sensor, and the frequency of the induction current generated by cutting the magnetic lines of force by the rotor of the asynchronous motor in the rotating magnetic field is The difference between the motor rotor frequency and the motor stator voltage frequency. The induction coil is used to induce the magnetic flux leakage of the motor. After processing, the stator voltage frequency signal and the difference frequency signal of the motor can be obtained. The synchronous speed of the motor can be obtained from the stator voltage frequency, and the slip speed of the motor can be obtained from the difference frequency signal. The difference is the asynchronous speed of the motor.

In one embodiment of the present invention, the three-phase current data of the motor can be measured by a Hall element current sensor, but it is not limited to this, and can also be measured by an AC/DC zero-flux current sensor, and can also be measured by an AC/DC current sensor. A zero-flux current sensor is used to measure. The temperature data of the cooling water inlet can be measured by a temperature sensor, which can be set on one side of the cooling water inlet. The cooling water outlet temperature data can be measured by a temperature sensor, which can be set on the side of the cooling water outlet. The cooling water flow data can be measured by the flow sensor, and the flow sensor can be set on the side of the cooling water inlet or outlet.

其中，I_peak表示三相电流数据中的峰值电流数 据，R_w(T)表示某一相定子绕组的温度为T时的电阻值。R_w(T)表示为R_w(T)＝R(T₀)*(1+α*(T-T₀))，其中，R(T₀)表示某一相定子绕组的温度为T₀时的电 阻值，T₀表示预设温度，T₀可以为20℃，也可以为25℃，还可以为30℃，α表 示修正系数。Step S20: Process the three-phase current data to obtain the copper loss heating power data q _cu of the stator winding, which is expressed as

Among them, I _peak represents the peak current data in the three-phase current data, and R _w (T) represents the resistance value when the temperature of the stator winding of a certain phase is T. R _w (T) is expressed as R _w (T)=R(T ₀ )*(1+α*(TT ₀ )), where R(T ₀ ) represents the temperature of the stator winding of a certain phase when the temperature is T ₀ Resistance value, T ₀ represents the preset temperature, T ₀ can be 20°C, 25°C, or 30°C, and α represents a correction coefficient.

R_w(T)可以表示为R_w(T)＝R(T₀)*(1+α*(T-T₀))，R(T₀)表示某一 相定子绕组的温度为T₀时的电阻值，T₀表示预设温度，T₀可以为20℃，也可以 为25℃，还可以为30℃，α表示修正系数。Referring to FIG. 2 , in an embodiment of the present invention, after obtaining the working data of the motor, the three-phase current data in the working data may be processed first to obtain peak current data in the three-phase current data. At the same time, since the number of stator windings is multi-phase, the structure and temperature of the multi-phase stator windings are the same, so it can be processed according to the resistance value when the temperature of the stator winding of a certain phase is T and the peak current data in the three-phase current data. , obtain the copper loss heating power data q _cu of the stator winding, expressed as

R _w (T) can be expressed as R _w (T)=R(T ₀ )*(1+α*(TT ₀ )), R(T ₀ ) represents the resistance when the temperature of the stator winding of a certain phase is T ₀ value, T ₀ represents the preset temperature, T ₀ can be 20°C, 25°C, or 30°C, and α represents the correction coefficient.

其中，k₁,k₂为待定系数，可以通过实验数据进行拟合得到，w为电机的转速数 据。Step S30: Process the rotational speed data and the three-phase current data to obtain iron loss heating power data of the stator core, wherein the iron loss heating power data includes hysteresis loss data, eddy current loss data and abnormal loss data. The iron loss heating power data q _fe of the stator core is expressed as

Among them, k ₁ , k ₂ are undetermined coefficients, which can be obtained by fitting the experimental data, and w is the speed data of the motor.

其中，k₁,k₂为待定系数，可以通过实验数 据进行拟合得到，w为电机的转速数据。磁滞损耗数据可以是铁磁体等在反复磁 化过程中因磁滞现象而消耗的能量。磁滞指铁磁材料的磁性状态变化时，磁化 强度滞后于磁场强度，它的磁通密度B与磁场强度H之间呈现磁滞回线关系。 经一次循环，每单位体积铁芯中的磁滞损耗正比于磁滞回线的面积。这部分能 量转化为热能，使设备升温，效率降低，因此会产生磁滞损耗数据。涡流损耗 数据可以是在变化的外磁场或自场中，超导体的常导基体或结构材料中感应的 涡流所产生的损耗。异常损耗数据可以是电机在异常状态下进行工作时所产生 的的损耗。Referring to FIG. 2 , in an embodiment of the present invention, the iron loss heating power data of the stator core can be obtained according to the rotational speed data and the three-phase current data. The iron loss heating power data may include hysteresis loss data, eddy current loss data, and abnormal loss data. The iron loss heating power data q _fe of the stator core can be expressed as

Among them, k ₁ , k ₂ are undetermined coefficients, which can be obtained by fitting the experimental data, and w is the speed data of the motor. The hysteresis loss data can be the energy dissipated by the hysteresis phenomenon in the process of repeated magnetization such as ferromagnets. Hysteresis means that when the magnetic state of a ferromagnetic material changes, the magnetization lags behind the magnetic field strength, and its magnetic flux density B and the magnetic field strength H show a hysteresis loop relationship. After one cycle, the hysteresis loss per unit volume in the core is proportional to the area of the hysteresis loop. This part of the energy is converted into heat, which heats up the device and reduces its efficiency, thus producing hysteresis loss data. Eddy current loss data can be losses due to eddy currents induced in a normally conducting matrix or structural material of a superconductor in a changing external or self-field. The abnormal loss data may be the loss generated when the motor works in an abnormal state.

Step S40: Process the cooling water inlet temperature data, the cooling water outlet temperature data and the cooling water flow data to obtain the cooling power data of the cooling water flow under forced convection, wherein the cooling power data includes the amount of heat taken away by the cooling water. The heat dissipation power data and the heating power data of the cooling water being heated. The heat dissipation power data P ₁ is expressed as P ₁ =C ₄ *M _r (T _{c_out} −T _{c_in} ), wherein C ₄ represents the thermal melting of the cooling water. M _r represents cooling water flow data. T _{c_out} represents the temperature data of the cooling water outlet. T _{c_in} represents the temperature data of the cooling water inlet. The heating power data P ₂ is expressed as

其中，C₄表示冷却水的热熔。M_r表示冷却水流量数据。T_{c_out}表示冷 却水出水口温度数据，T_{c_in}表示冷却水进水口温度数据。Referring to FIG. 2, in one embodiment of the present invention, the cooling power data of the cooling water flow under forced convection can be obtained according to the cooling water inlet temperature data, the cooling water outlet temperature data and the cooling water flow data. The heat dissipation power data may include heat dissipation power data that the cooling water takes away heat and heating power data that the cooling water is heated. The heat dissipation power data can be expressed as the power dissipated by the internal components of the motor, and the heating power data can be expressed as the power of the cooling water temperature rising due to heat absorption. The heat dissipation power data P ₁ can be expressed as P ₁ =C ₄ *M _r (T _{c_out} -T _{c_in} ), and the heating power data P ₂ can be expressed as

Among them, C ₄ represents the thermal melting of cooling water. M _r represents cooling water flow data. T _{c_out} represents the temperature data of the cooling water outlet, and T _{c_in} represents the temperature data of the cooling water inlet.

其中，k表示第k个采样周期。T表示采样周期。C₁表示定子绕组的等效热容。C₂定子铁芯的等效热 容。C₃表示冷却水套的等效热容。R_wm表示定子绕组对定子铁芯齿槽的等效热阻。 R_ms表示定子铁芯对冷却水套的等效热阻。q_cu表示定子绕组的铜损发热功率数据 q_fe表示定子铁芯的铁损发热功率数据。q_cs表示冷却系统的散热功率数据。Step S50, processing copper loss heating power data, iron loss heating power data, and heat dissipation power data to obtain motor stator temperature data, wherein the motor stator temperature data includes temperature data _Tw of the motor stator winding and motor stator iron core temperature data T _m and motor cooling jacket temperature data T _s ,

Among them, k represents the kth sampling period. T represents the sampling period. C ₁ represents the equivalent heat capacity of the stator winding. C ₂ Equivalent heat capacity of the stator core. C3 represents the equivalent heat capacity _of the cooling water jacket. R _wm represents the equivalent thermal resistance of the stator winding to the slots of the stator core. R _ms represents the equivalent thermal resistance of the stator core to the cooling water jacket. q _cu represents the copper loss heating power data of the stator winding, and q _fe represents the iron loss heating power data of the stator core. q _cs represents the cooling power data of the cooling system.

Referring to FIG. 2 , in an embodiment of the present invention, motor stator temperature data can be obtained according to copper loss heating power data, iron loss heating power data, and heat dissipation power data. Specifically, in the motor stator temperature data, the temperature data _Tw of the motor stator winding, the motor stator iron core temperature data T _m and the motor cooling water jacket temperature data T _s are used as variables to be estimated. According to Kirchhoff's current law, it can be get:

其中，q_cu表示定子绕组的铜损发热功率数 据。q_fe表示定子铁芯的铁损发热功率数据。C₁表示定子绕组的等效热容。C₂定 子铁芯的等效热容。C₃表示冷却水套的等效热容。C₄表示冷却水的热容。R_wm表 示定子绕组对定子铁芯齿槽的等效热阻。R_ms表示定子铁芯对冷却水套的等效热 阻。R_sc表示冷却水套的等效热阻。T_c-out表示电机冷却水套的冷却水出水口温度 数据。T_c-in表示电机冷却水套的冷却水进水口温度数据。M_r表示冷却水流量数据。 此时可以根据公式(1)～(5)，得到系统状态方程，表示为：

其中，

Among them, q _cu represents the copper loss heating power data of the stator winding. q _fe represents the iron loss heating power data of the stator core. C ₁ represents the equivalent heat capacity of the stator winding. C ₂ Equivalent heat capacity of the stator core. C3 represents the equivalent heat capacity _of the cooling water jacket. _C4 represents the heat capacity of the cooling water. R _wm represents the equivalent thermal resistance of the stator winding to the slots of the stator core. R _ms represents the equivalent thermal resistance of the stator core to the cooling water jacket. R _sc represents the equivalent thermal resistance of the cooling jacket. T _c-out represents the cooling water outlet temperature data of the motor cooling water jacket. T _c-in represents the cooling water inlet temperature data of the motor cooling jacket. M _r represents cooling water flow data. At this time, according to formulas (1) to (5), the system state equation can be obtained, which is expressed as:

in,

由于参数a₁,a₂,C₁,C₂,C₃可以通过试验数据进行测定，对于一个确定的电机系统，其参数a₁,a₂,C₁,C₂,C₃可以认为是已

Since parameters a ₁ , a ₂ , C ₁ , C ₂ , C ₃ can be determined through experimental data, for a certain motor system, its parameters a ₁ , a ₂ , C ₁ , C ₂ , C ₃ can be considered as

其中，T表示采样周期，k表示第k 个采样周期，L^-1表示拉普拉斯逆变换符号，s表示拉普拉斯变量，I表示单位矩阵，

为了减少嵌入式系统的计算量，也可以采用近似离散化方 法对由公式(6)描述的系统进行离散化，可得到

因此，由确定的 a₁,a₂,C₁,C₂,C₃的参数数值，实时计算的q_cu、q_fe以及q_cs，在嵌入式系统中选定的 采样时间，采样周期等于该估计模型的调用周期，根据递推公式(7)或(8)， 则可以实时估计出电机定子温度数据中电机定子绕组的温度数据T_w、电机定子 铁芯温度数据T_m以及电机冷却水套温度数据T_s。Referring to FIG. 2 , in one embodiment of the present invention, the cooling power data q _cs of the cooling system is related to the temperature data Tw of the motor stator _windings , the motor stator iron core temperature data T _m and the motor cooling in the motor stator temperature data The water jacket temperature data T _s has a great influence, so it is necessary to accurately measure the cooling power data q _cs of the cooling system. The formula (6) can be discretized first to get

Among them, T represents the sampling period, k represents the kth sampling period, L ^-1 represents the inverse Laplace transform symbol, s represents the Laplace variable, I represents the identity matrix,

In order to reduce the calculation amount of the embedded system, the approximate discretization method can also be used to discretize the system described by the formula (6), we can get

Therefore, from the determined parameter values of a ₁ , a ₂ , C ₁ , C ₂ , C ₃ , q _cu , q _fe and q _cs calculated in real time, the sampling time selected in the embedded system, the sampling period is equal to the Estimating the calling cycle of the model, according to the recursive formula (7) or (8), the temperature data _Tw of the motor stator winding, the temperature data T _m of the motor stator iron core and the motor cooling water jacket in the motor stator temperature data can be estimated in real time. Temperature data T _s .

再基于当前的实际转速和限定的最大工作功率 |P_allow|，计算电机可以使用的扭矩范围，即电机可用扭矩的计算。最后根据计算 出的可用扭矩，将电机工作扭矩限制在可用扭矩范围内。Referring to FIG. 2 , in an embodiment of the present invention, the temperature data _Tw of the motor stator winding, the temperature data T _m of the motor stator iron core and the temperature data of the motor cooling water jacket can be estimated in real time according to the motor stator temperature data. T _s , which limits the working torque of the motor in the electric and power generation states. Prevent the motor from working in an overheated state, causing the components inside the motor to be burned. For example, it is possible to set the maximum power P _allow that limits the electric motor and the power generation state of the motor based on the stator temperature first, and can perform a linear power reduction setting according to different temperatures. For example, when the stator temperature is lower than _T0 , the output working power of the motor is allowed to work in the full power range, and when the temperature is higher _than T1, the output working power of the motor is limited to zero power. Wherein, T ₀ may be 140 degrees Celsius, 150 degrees Celsius, or 155 degrees Celsius. T ₁ may be 160 degrees Celsius, 170 degrees Celsius, or 180 degrees Celsius, and T ₁ >T ₀ . It can be seen from this that the maximum power P _allow in the state of electric and power generation of the motor is limited based on the stator temperature, which can be expressed as

Then, based on the current actual speed and the limited maximum working power |P _allow |, the torque range that can be used by the motor is calculated, that is, the calculation of the available torque of the motor. Finally, according to the calculated available torque, the working torque of the motor is limited within the available torque range.

It can be seen that in the above scheme, the temperature data of the motor stator winding, the motor stator iron core temperature data and the motor cooling water jacket temperature data in the motor stator temperature data can be accurately estimated according to the cooling water flow rate under forced convection. It can be used for the protection of the motor to ensure the reliable, safe and stable operation of the motor.

It should be understood that the size of the sequence numbers of the steps in the above embodiments does not mean the sequence of execution, and the execution sequence of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention.

Referring to Fig. 3 and Fig. 4 , the present invention also provides a device for estimating the temperature of the motor stator, and the device for estimating the temperature of the motor stator corresponds to the method for estimating the temperature of the motor stator. The apparatus for estimating the stator temperature of the motor may include a data acquisition module 10, a copper loss heating processing module 20, an iron loss heating processing module 30, a heat dissipation power processing module 40, and a stator temperature estimation module 50.

In one embodiment of the present invention, the data acquisition module 10 can be used to acquire working data of the motor, and the working data includes rotational speed data, three-phase current data, cooling water inlet temperature data, cooling water outlet temperature data, and cooling water flow data . Specifically, the working data of the motor can be obtained first. The working data of the motor can include the rotational speed data of the motor, the three-phase current data of the motor, the temperature data of the cooling water inlet of the cooling system, the temperature data of the cooling water outlet of the cooling system, and the cooling water. Cooling water flow data for the system. The speed data of the motor can be measured by the speed sensor. The three-phase current data of the motor can be measured by the Hall element current sensor. The cooling water outlet temperature data can be measured by a temperature sensor.

其 中，I_peak表示三相电流数据中的峰值电流数据，R_w(T)表示某一相定子绕组的温 度为T时的电阻值。R_w(T)表示为R_w(T)＝R(T₀)*(1+α*(T-T₀))，其中，R(T₀)表示某 一相定子绕组的温度为T₀时的电阻值，T₀表示预设温度，T₀可以为20℃，也可 以为25℃，还可以为30℃，α表示修正系数。In an embodiment of the present invention, the copper loss heating processing module 20 can be used to process the three-phase current data to obtain the copper loss heating power data _qcu of the stator winding, which is expressed as

Among them, I _peak represents the peak current data in the three-phase current data, and R _w (T) represents the resistance value when the temperature of the stator winding of a certain phase is T. R _w (T) is expressed as R _w (T)=R(T ₀ )*(1+α*(TT ₀ )), where R(T ₀ ) represents the temperature of the stator winding of a certain phase when the temperature is T ₀ Resistance value, T ₀ represents the preset temperature, T ₀ can be 20°C, 25°C, or 30°C, and α represents a correction coefficient.

其中，k₁,k₂为待定系数，可以通 过实验数据进行拟合得到，w为电机的转速数据。In an embodiment of the present invention, the iron loss heating processing module 30 may be configured to process rotational speed data and three-phase current data to obtain iron loss heating power data of the stator core, wherein the iron loss heating power data includes hysteresis loss data, eddy current loss data, and abnormal loss data. The iron loss heating power data q _fe of the stator core is expressed as

Among them, k ₁ , k ₂ are undetermined coefficients, which can be obtained by fitting the experimental data, and w is the speed data of the motor.

In one embodiment of the present invention, the heat dissipation power processing module 40 may be configured to process the cooling water inlet temperature data, the cooling water outlet temperature data and the cooling water flow data to obtain the cooling power data of the cooling water flow under forced convection , wherein the heat dissipation power data includes the heat dissipation power data that the cooling water takes away heat and the heating power data that the cooling water is heated. The heat dissipation power data P ₁ is expressed as P ₁ =C ₄ *M _r (T _{c_out} −T _{c_in} ), wherein C ₄ represents the thermal melting of the cooling water. M _r represents cooling water flow data. T _{c_out} represents the temperature data of the cooling water outlet. T _{c_in} represents the temperature data of the cooling water inlet. The heating power data P ₂ is expressed as

其中，k表示第k 个采样周期。T表示采样周期。C₁表示定子绕组的等效热容。C₂定子铁芯的等效热容。C₃表示冷却水套的等效热容。R_wm表示定子绕组对定子铁芯齿槽的等效热阻。 R_ms表示定子铁芯对冷却水套的等效热阻。q_cu表示定子绕组的铜损发热功率数据 q_fe表示定子铁芯的铁损发热功率数据。q_cs表示冷却系统的散热功率数据。In an embodiment of the present invention, the stator temperature estimation module 50 may be configured to process copper loss heating power data, iron loss heating power data, and heat dissipation power data to obtain motor stator temperature data, where the motor stator temperature data includes the motor stator The temperature data T _w of the winding, the temperature data T _m of the motor stator iron core and the temperature data T _s of the motor cooling water jacket,

Among them, k represents the kth sampling period. T represents the sampling period. C ₁ represents the equivalent heat capacity of the stator winding. C ₂ Equivalent heat capacity of the stator core. C3 represents the equivalent heat capacity _of the cooling water jacket. R _wm represents the equivalent thermal resistance of the stator winding to the slots of the stator core. R _ms represents the equivalent thermal resistance of the stator core to the cooling water jacket. q _cu represents the copper loss heating power data of the stator winding, and q _fe represents the iron loss heating power data of the stator core. q _cs represents the cooling power data of the cooling system.

For the specific limitation of the device for estimating the temperature of the motor stator, please refer to the limitation on the intelligent question and answer processing method above, which will not be repeated here. Each module in the above-mentioned apparatus for estimating the stator temperature of a motor can be implemented in whole or in part by software, hardware and combinations thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, and can also be stored in the memory in the computer device in the form of software, so that the processor can call and execute the corresponding operations of the above-mentioned modules.

Referring to Fig. 5, the present invention also provides a computer device, and the computer device can be a server. The computer device includes a processor, memory, a network interface, and a database connected by a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes non-volatile and/or volatile storage media, internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the execution of the operating system and computer programs in the non-volatile storage medium. The network interface of the computer device is used to communicate with external clients through a network connection. The computer program, when executed by the processor, implements the server-side functions or steps of a method for estimating stator temperature of a motor.

Referring to Fig. 6, the present invention also provides another computer device, and the computer device can be a client. The computer equipment includes a processor, memory, a network interface, a display screen, and an input device connected by a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes non-volatile storage media, internal memory. The nonvolatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the execution of the operating system and computer programs in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external server over a network connection. The computer program, when executed by a processor, implements client-side functions or steps of a method for estimating a motor stator temperature.

In one embodiment of the present invention, a computer equipment is provided, comprising a memory, a processor and a computer program stored in the memory and running on the processor, the processor implements the following steps when executing the computer program:

Obtain the working data of the motor, including rotational speed data, three-phase current data, cooling water inlet temperature data, cooling water outlet temperature data, and cooling water flow data.

The three-phase current data is processed to obtain the copper loss heating power data of the stator winding.

The speed data and three-phase current data are processed to obtain the iron loss heating power data of the stator core, wherein the iron loss heating power data includes hysteresis loss data, eddy current loss data and abnormal loss data

The cooling water inlet temperature data, cooling water outlet temperature data and cooling water flow data are processed to obtain the cooling power data of the cooling water flow under forced convection, wherein the cooling power data includes the cooling water to take away the heat cooling power data The heating power data with the cooling water being heated.

Process the copper loss heating power data, iron loss heating power data, and heat dissipation power data to obtain motor stator temperature data, where the motor stator temperature data includes the temperature data of the motor stator winding, the motor stator iron core temperature data, and the motor cooling water jacket temperature data.

In one embodiment of the present invention, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented:

Obtain the working data of the motor, including rotational speed data, three-phase current data, cooling water inlet temperature data, cooling water outlet temperature data, and cooling water flow data.

The three-phase current data is processed to obtain the copper loss heating power data of the stator winding.

The speed data and three-phase current data are processed to obtain the iron loss heating power data of the stator core, wherein the iron loss heating power data includes hysteresis loss data, eddy current loss data and abnormal loss data

The cooling water inlet temperature data, cooling water outlet temperature data and cooling water flow data are processed to obtain the cooling power data of the cooling water flow under forced convection, wherein the cooling power data includes the cooling water to take away the heat cooling power data The heating power data with the cooling water being heated.

Process the copper loss heating power data, iron loss heating power data, and heat dissipation power data to obtain motor stator temperature data, where the motor stator temperature data includes the temperature data of the motor stator winding, the motor stator iron core temperature data, and the motor cooling water jacket temperature data.

It should be noted that, with regard to the functions or steps that can be implemented by the computer-readable storage medium or computer equipment, reference may be made to the relevant descriptions on the server side and the client side in the foregoing method embodiments. Describe them one by one.

Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be implemented by instructing relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage In the medium, when the computer program is executed, it may include the processes of the above-mentioned method embodiments. Wherein, any reference to memory, storage, database or other medium used in the various embodiments provided in this application may include non-volatile and/or volatile memory. Nonvolatile memory may include read only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ES DRAM), synchronous Link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM) and so on.

In the description of this specification, a description with reference to the terms "this embodiment", "example", "specific example", etc. means that a specific feature, structure, material or characteristic described in connection with this embodiment or example is included in at least one aspect of the present invention in one embodiment or example. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The embodiments of the present invention disclosed above are only used to help illustrate the present invention. The examples do not exhaustively describe all the details, nor do they limit the invention to only the specific embodiments described. Obviously, many modifications and variations are possible in light of the contents of this specification. The present specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is to be limited only by the claims and their full scope and equivalents.

Claims (10)

1. A method for estimating the temperature of a motor stator, comprising: Acquiring working data of the motor, the working data includes rotational speed data, three-phase current data, cooling water inlet temperature data, cooling water outlet temperature data, and cooling water flow data; processing the three-phase current data to obtain the copper loss heating power data of the stator winding; processing the rotational speed data and the three-phase current data to obtain iron loss heating power data of the stator core; processing the cooling water inlet temperature data, the cooling water outlet temperature data and the cooling water flow data to obtain the cooling power data of the cooling water flow under forced convection; The copper loss heating power data, the iron loss heating power data and the heat dissipation power data are processed to obtain motor stator temperature data. 2 . The method for estimating the temperature of the motor stator according to claim 1 , wherein the copper loss heating power data q _cu is expressed as: 2 .

in, I _peak represents the peak current data in the three-phase current data, R _w (T) represents the resistance value when the temperature of the stator winding of a certain phase is T. 3. The method for estimating motor stator temperature according to claim 2, wherein the R _w (T) is expressed as R _w (T)=R(T ₀ )*(1+α*(TT ₀ ) ),in, R(T ₀ ) represents the resistance value of the stator winding of a certain phase when the temperature is T ₀ , T ₀ represents the preset temperature, α represents a correction coefficient. 4 . The method for estimating the temperature of the motor stator according to claim 1 , wherein the iron loss heating power data q _fe of the stator core is expressed as: 5 .

in, k ₁ , k ₂ represent undetermined coefficients, w represents the rotational speed data. 5 . The method for estimating motor stator temperature according to claim 1 , wherein the motor stator temperature data includes motor stator winding temperature data, motor stator iron core temperature data, and motor cooling water jacket temperature data. 6 . 6 . The method for estimating the temperature of the motor stator according to claim 5 , wherein the motor stator winding temperature data _Tw , the motor stator iron core temperature data T _m and the motor cooling water jacket temperature data T The relationship between _s is expressed as

in, k represents the kth sampling period. T represents the sampling period. C ₁ represents the equivalent heat capacity of the stator winding. C ₂ Equivalent heat capacity of the stator core. C3 represents the equivalent heat capacity _of the cooling water jacket. R _wm represents the equivalent thermal resistance of the stator winding to the slots of the stator core. R _ms represents the equivalent thermal resistance of the stator core to the cooling water jacket. q _cs represents the cooling power data of the cooling system. 7 . The method for estimating the temperature of the motor stator according to claim 5 , wherein the motor stator winding temperature data T _w , the motor stator iron core temperature data T _m and the motor cooling water jacket temperature data T The relationship between _s is expressed as

in,

L ^-1 represents the inverse Laplace transform symbol, s is the Laplace variable, I represents the identity matrix. 8. A device for estimating the temperature of a motor stator, comprising: a data acquisition module for acquiring working data of the motor, the working data including rotational speed data, three-phase current data, cooling water inlet temperature data, cooling water outlet temperature data and cooling water flow data; The copper loss heating processing module is used to process the three-phase current data to obtain the copper loss heating power data of the stator winding; an iron loss heating processing module, configured to process the rotational speed data and the three-phase current data to obtain iron loss heating power data of the stator core; a cooling power processing module, configured to process the cooling water inlet temperature data, the cooling water outlet temperature data and the cooling water flow data to obtain cooling water flow cooling power data under forced convection; and The stator temperature estimation module is configured to process the copper loss heating power data, the iron loss heating power data and the heat dissipation power data to obtain motor stator temperature data. 9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the computer program as claimed in the claims Steps of the method for estimating the stator temperature of a motor according to any one of 1 to 7. 10. A computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the temperature of the motor stator according to any one of claims 1 to 7 is realized steps of the estimation method.

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