Locomotive traction motor shaft temperature control method, medium and equipment

Abstract

The invention relates to the technical field of traction motor shaft temperature control, and discloses a locomotive traction motor shaft temperature control method, medium and equipment, and the method comprises the steps: obtaining bearing parameters, judging whether a bearing is abnormal or not, if yes, giving an alarm prompt, and if not, entering the next step; calculating whether an axle temperature alarm is generated in the nearest climbing process in the current operation state or not through an axle temperature prediction method, if not, continuing to operate according to the current state, and if so, entering the next step; and variable conditions under which axle temperature alarm does not occur are calculated, and a fan operation strategy is adjusted to enable the follow-up traction motor not to generate axle temperature alarm. According to the method, the operation strategy of the fan can be optimized according to parameters such as environment and lines, the temperature of the bearing and the temperature of the motor are reduced under various harsh conditions, meanwhile, whether a shutter filter screen is blocked or not and whether the bearing breaks down or not are intelligently judged, and the shaft temperature alarm problem caused by various reasons is early warned and solved through various means and modes; the temperature of a traction motor during locomotive operation is reduced; and the service life of the motor is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of traction motor shaft temperature control, and in particular to a locomotive traction motor shaft temperature control method, medium and equipment. Background Art

[0002] Freight locomotives such as the HXD1 and HXD2 often experience traction motor bearing overtemperature alarms due to a combination of factors, including heavy loads, long slopes, multiple tunnels, high temperatures, and bearing wear. This seriously impacts the safe and stable operation of the locomotive. Bearing overtemperature alarms also indicate high core temperatures in the traction motor. Prolonged operation at elevated temperatures can easily degrade the insulation material, leading to motor burnout and failure, severely impacting the motor's service life and the locomotive's safe operation.

[0003] At present, the main methods to solve the above problems are as follows:

[0004] 1) Raise the alarm temperature limit, for example, by adjusting the maximum temperature threshold for the non-drive-end bearing of the traction motor from 90°C to 100°C, while maintaining the 55K temperature rise. This approach only superficially eliminates the alarm problem and does not improve the actual bearing temperature or motor core temperature, thus failing to fundamentally resolve the issue.

[0005] 2) Adjust the temperature rise ambient reference temperature specified in the standard. For example, by compensating for the ambient temperature of the non-drive-end bearing of the traction motor, the ambient temperature value can be increased by 15°C as the cooling medium temperature. Again, this approach is only effective for temperature rise alarms, not for overtemperature alarms, and only superficially addresses some of the alarm issues.

[0006] 3) Improve the temperature measurement location of the composite sensor. For example, add a cover to the non-drive-end bearing temperature sensor to block or reduce the impact of hot air from the traction motor's air outlet on the sensor. This solution changes the temperature sensor's measured temperature, but the effect is very limited and does not help reduce the actual shaft temperature or the motor core's operating temperature.

[0007] 4) The traction motor control logic is modified based on axle temperature. For example, when the temperature at the motor drive end of a certain axle exceeds 105°C, the traction command is linearly reduced. At 115°C, the command value drops to 0. After the temperature drops below the limit, the motor torque command is re-applied to restore traction. This solution can easily cause locomotive safety issues. For example, alarms often occur on long slopes, and reduced power operation can easily cause the locomotive to stop, leading to safety accidents.

[0008] In summary, the current methods for solving the shaft temperature alarm problem have the following shortcomings: (1) The solution is single and can only improve or solve some alarm problems. (2) It cannot actually improve the bearing temperature and motor core temperature and is only useful for troubleshooting the alarm. (3) There is still the risk of the actual operating temperature being too high, which will deteriorate the working environment of the motor and bearings and reduce their service life.

[0009] To sum up, there is an urgent need for a locomotive traction motor shaft temperature control method, medium and equipment to fundamentally improve the traction motor core temperature, completely solve the bearing temperature alarm problem, improve the bearing operating conditions, extend the service life of the bearing and motor, and effectively ensure the safe operation of the locomotive. Summary of the Invention

[0010] The purpose of the present invention is to provide a method, medium and equipment for controlling the shaft temperature of a locomotive traction motor. The specific technical solution is as follows:

[0011] A method for controlling the shaft temperature of a locomotive traction motor, comprising:

[0012] Step 1: Obtain the bearing parameters of the locomotive traction motor and determine whether the bearing is abnormal. If abnormal, an alarm will be issued; if normal, proceed to the next step;

[0013] Step 2: Obtain the current locomotive information, cooling fan operation information, environmental information, and line information. Use the axle temperature prediction method to calculate whether an axle temperature alarm will occur during the nearest climbing process under the current operating state. If no alarm occurs, continue operation according to the current state. If an alarm occurs, proceed to the next step.

[0014] Step 3: Calculate the variable conditions for preventing the occurrence of shaft temperature alarms, and adjust the fan operation strategy so that subsequent traction motors do not have shaft temperature alarms.

[0015] Preferably, the method for determining whether the bearing is abnormal in step 1 includes:

[0016] Obtain vibration acceleration and temperature data of the bearings of the locomotive traction motor;

[0017] Through data preprocessing and feature extraction algorithms, a bearing vibration characteristic state index is constructed to preliminarily judge the bearing vibration condition. If the characteristic state index H < 0.5, the bearing is judged to be normal.

[0018] If the characteristic state index H ≥ 0.5, the vibration acceleration data is subjected to Fourier transform to calculate the characteristic frequency and obtain a spectrum diagram based on the vibration acceleration;

[0019] Compare the spectrum diagram with the bearing fault frequency to determine the bearing fault type;

[0020] The process of constructing the characteristic state index is as follows: first, based on the acceleration sensor data, characteristic values ​​including effective value, peak-to-peak value, high-to-low frequency energy ratio, kurtosis, impact decibel, and margin factor are calculated, one or more key features that best reflect the bearing state are selected from the characteristic values, and then the characteristic state index is constructed. The construction formula is:

[0021]

[0022] Where H is the constructed feature state index, x is the selected key eigenvalue, n is the number of eigenvalues, which is up to 13, w is the weight of each eigenvalue, and the subscript i = 123…n.

[0023] Preferably, the step 2 specifically includes:

[0024] Obtain the current locomotive gross weight m, vehicle speed v, ambient temperature t, cooling fan operating frequency f, traction motor temperature t1, slope length L1, slope a, and distance to the ramp L2;

[0025] A shaft temperature prediction method is used to calculate whether a shaft temperature alarm will occur during climbing under the current situation. The shaft temperature prediction method includes:

[0026] The climbing power P of the locomotive is calculated based on the locomotive gross weight m, vehicle speed v and slope a. The expression is as follows:

[0027] P = m*g*v*sina;

[0028] The required output power P1 of the traction motor is calculated based on the required locomotive climbing power P and the motor efficiency η. The expression is as follows:

[0029] P1=P / η;

[0030] Combined with the traction motor air volume-power-shaft temperature relationship curve under tunnel and non-tunnel conditions, the expected bearing temperature T under the current air volume and the required locomotive climbing power P is calculated. q , the specific calculation is as follows:

[0031] The temperature rise at the top of the slope is calculated based on the following formula:

[0032] T=k1*P1*L1 / v-k2*Q d +k3*t;

[0033] Among them, T is the temperature rise value at the top of the slope, k1, k2, k3 are empirical coefficients related to the vehicle model, Q d is the current wind volume;

[0034] Expected bearing temperature T under current air volume and required locomotive climbing power P q Calculated using the following formula:

[0035] T q =T0+T;

[0036] Where T0 is the temperature at the bottom of the slope;

[0037] Determine the T q Whether the preset alarm temperature is reached, that is, whether T q <120℃ and T q -t<80℃, no shaft temperature alarm will occur;

[0038] If T q ≥120℃ or T q -t≥80℃, an axle temperature alarm will occur.

[0039] Preferably, the step three specifically includes:

[0040] When the calculation result is T q ≥120℃ or T q -t≥80℃, the maximum air volume Q of the cooling fan max Recalculate T q , and judge the climbing process T q Check whether the alarm threshold is exceeded. If not, adjust the operating frequency of the cooling fan to the maximum frequency according to the current position and the climbing distance. When the distance L2 = 0, adjust the operating frequency of the cooling fan to the maximum frequency.

[0041] If the cooling fan is running at maximum air volume or full frequency and still reaches the alarm condition, the maximum air volume Q max =1.45m 3 / s and preset alarm temperature T q =120℃ are the two parameters as the boundary, and the highest slope bottom temperature T0 without alarm is calculated by reverse calculation through the traction motor air volume-power-axis temperature relationship curve;

[0042] Combined with the current traction motor temperature T d , fan air volume or frequency and the distance from the climbing position L2, according to the balance between heating and heat dissipation of the traction motor on flat or downhill roads, the expression is as follows:

[0043] δT=k5*P1*L2 / v-k6*Q d ;

[0044] Among them, k5 and k6 are empirical coefficients related to vehicle models;

[0045] Let T d -T0=δT, calculate the shortest distance L from the bottom of the slope under maximum wind volume 2min ;

[0046] According to the current position and the distance of climbing, when the distance L2=L 2minWhen the fan is running, adjust the fan frequency to the maximum frequency so that the shaft temperature alarm will not occur later;

[0047] When calculating L 2min >When the distance from the locomotive to the bottom of the slope is L2, let L2 = L 2min , according to δT=k5*P1*L2 / v-k6*Q d Calculate the speed v of the locomotive. If v>v min , v min is the minimum speed of the locomotive on this section, then immediately reduce the locomotive speed to v min , and adjust the fan frequency to 60Hz to ensure that no shaft temperature alarm occurs later;

[0048] When v <v min Even if the locomotive reduces its speed in time and is under the condition of maximum ventilation, an alarm will occur during the subsequent climbing. At this time, it is necessary to stop the vehicle and restart it when the traction motor temperature drops to the lowest temperature where no alarm will occur, so as to ensure that the locomotive will not have an axle temperature alarm.

[0049] Preferably, the step three further comprises:

[0050] Obtain normal air volume data at the same frequency to determine the blockage status of the low-resistance louver filter;

[0051] Based on the blockage status and the variable condition that no axle temperature alarm occurs, determine whether an axle temperature alarm will occur when the fan at the bottom of the slope runs at the maximum wind speed. If an axle temperature alarm occurs, it is recommended to clean the low-resistance louver filter after the locomotive returns to the depot and set the current blockage status to a critical state.

[0052] Preferably, the method further comprises step 4, wherein the step 4 comprises:

[0053] The parameters in steps 1 to 3 are recorded to automatically form a database.

[0054] The present invention also provides a readable storage medium having computer program instructions stored thereon, which implements the above-mentioned locomotive traction motor shaft temperature control method when the computer program instructions are executed by a processor.

[0055] The present invention also provides an electronic device comprising: at least one processor, at least one memory and computer program instructions stored in the memory, when the computer program instructions are executed by the processor, the locomotive traction motor shaft temperature control method as described above is performed.

[0056] The application of the technical solution of the present invention has the following beneficial effects:

[0057] A locomotive traction motor shaft temperature control method includes: obtaining bearing parameters of the locomotive traction motor, determining whether the bearing is abnormal, issuing an alarm if abnormal, and proceeding to the next step if normal; obtaining current locomotive information, cooling fan operation information, environmental information, and line information, and calculating whether a shaft temperature alarm will occur during the nearest hill climb under the current operating state using a shaft temperature prediction method; if no alarm will occur, continuing operation according to the current state; if an alarm will occur, proceeding to the next step; calculating variable conditions for preventing a shaft temperature alarm, and adjusting the fan operation strategy to prevent subsequent traction motor shaft temperature alarms. The method of the present invention can optimize the fan operation strategy based on parameters such as the environment, actual line conditions, shaft temperature data, and current fan state, significantly increasing the air volume or the holding time of high air volume, and increasing heat dissipation, thereby reducing bearing and motor temperatures under various harsh conditions. This method can provide early warning and resolve shaft temperature alarm issues caused by various reasons, and can also intelligently determine whether a low-resistance louver filter is clogged or whether a bearing is faulty. Bearing temperature alarm issues caused by various reasons can be resolved through various means and methods, and the method has the characteristics of automation, intelligence, and universal applicability.

[0058] In addition to the above-described objects, features and advantages, the present invention has other objects, features and advantages. The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] The accompanying drawings, which constitute part of the present invention, are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0060] Figure 1 The present invention is a flowchart of a method for controlling the shaft temperature of a locomotive traction motor according to an embodiment of the present invention. DETAILED DESCRIPTION

[0061] The embodiments of the present invention are described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered by the claims.

[0062] The locomotive in this embodiment is a freight locomotive and comprises at least three components: low-resistance louvers, a high-performance fan, and a fan energy efficiency monitoring system. The low-resistance louvers include an air deflector, dust screen, sealing strip, frame, filter, and mounting holes. The high-performance fan is an axial-flow centrifugal fan, consisting of an air inlet duct, impeller, fan cylinder, and motor. The fan energy efficiency monitoring system primarily comprises sensors located in the duct and fan, a data acquisition box, a data processing host, an online bearing monitoring system, a positioning system, and a control system.

[0063] The present embodiment provides a method for controlling the shaft temperature of a locomotive traction motor. This method also significantly increases the ventilation volume of the traction motor while maintaining essentially the same power, noise, and other indicators by adjusting the structural parameters of the existing traction fan. The method increases the fan impeller diameter by 5 mm, reduces the blade inlet angle by 4°, and adjusts the wind tube guide vanes by 3°. This reduces the motor core temperature, thereby reducing the heat transferred from the core position to the traction motor bearings and lowering the bearing temperature. By optimizing the spacing of the louvers, the louver resistance is reduced. This in turn reduces the resistance of the ventilation and heat dissipation system composed of the louvers, air inlet duct, fan, and motor. The reduction in system resistance causes the actual operation of the fan to shift toward the high-flow operating point, effectively further increasing the ventilation volume.

[0064] Compared with the existing air inlet louvers on the side top of the locomotive, the low-resistance louvers can reduce the flow resistance by about 5%; compared with the traction fans on existing locomotives, the high-performance fans designed through parametric optimization can increase the air volume by 8% to 15%.

[0065] refer to Figure 1 , a locomotive traction motor shaft temperature control method, comprising:

[0066] Step 1: Obtain the bearing parameters of the locomotive traction motor through the fan energy efficiency monitoring system to determine whether the bearing is abnormal. If abnormal, an alarm will be issued; if normal, proceed to the next step;

[0067] Methods for determining whether a bearing is abnormal include:

[0068] Obtain vibration acceleration and temperature data of the bearings of the locomotive traction motor;

[0069] Through data preprocessing, feature extraction algorithms, or bearing vibration characteristic indicators, the bearing vibration acceleration data undergoes data cleaning, calculation, and Fourier transformation to obtain vibration characteristic values. The main characteristic values ​​in this embodiment are effective value, peak-to-peak value, high-to-low frequency energy ratio, and kurtosis. The effective value and peak-to-peak value are used to preliminarily determine the bearing vibration condition. If the characteristic value is small, the bearing is considered normal.

[0070] Depending on the specific situation, some or a combination of these characteristic values ​​are selected as diagnostic indicators. In this embodiment, the peak value and impact DB are selected as characteristic indicators for determining whether the bearing is normal. If the characteristic state indicator H ≥ 0.5, the vibration acceleration data is Fourier transformed to calculate the characteristic frequency and obtain a spectrum diagram based on the vibration acceleration;

[0071] The process of constructing the characteristic state index is as follows: first, based on the acceleration sensor data, characteristic values ​​including effective value, peak-to-peak value, high-to-low frequency energy ratio, kurtosis, impact decibel, and margin factor are calculated, one or more key features that best reflect the bearing state are selected from the characteristic values, and then the characteristic state index is constructed. The construction formula is:

[0072]

[0073] Where H is the constructed feature state index, x is the selected key eigenvalue, n is the number of eigenvalues, which is up to 13, w is the weight of each eigenvalue, and the subscript i = 123…n.

[0074] The spectrum is compared with the bearing fault frequency information provided by the bearing manufacturer to determine the type of bearing fault. For bearings that may be faulty, the characteristic frequency is further compared with the characteristic frequencies of the bearing's inner and outer rings, as well as the rolling element faults, to determine the final bearing condition. This process is performed and updated daily to help ensure the normal condition of the bearings before locomotive operation. If the characteristic frequency matches the fault frequency of the bearing's inner and outer rings, or the rolling element, and the temperature rise is high, the bearing is considered faulty. If the bearing is damaged, an axle temperature alarm will also be triggered.

[0075] Step 2: Obtain current locomotive information, cooling fan operation information, environmental information, and line information through on-board sensors, load them into the system in advance, and transmit the collected data to each data acquisition box and a data processing host via a 485 communication line. The calculation and control in this embodiment are all performed in the data processing host.

[0076] The shaft temperature prediction method is used to calculate whether a shaft temperature alarm will occur during the nearest climbing process in the current operating state. If no alarm occurs, the operation continues according to the current state. If an alarm occurs, the next step is entered. Step 2 specifically includes:

[0077] Obtain the current locomotive gross weight m, vehicle speed v, ambient temperature t, cooling fan operating frequency f, traction motor temperature t1, slope length L1, slope a, and distance to the ramp L2;

[0078] The shaft temperature prediction method is used to calculate whether a shaft temperature alarm will occur during the current climbing situation. The shaft temperature prediction method is a comprehensive judgment method that combines theoretical methods with historical data. The theoretical part includes:

[0079] The climbing power P of the locomotive is calculated based on the locomotive gross weight m, vehicle speed v and slope a. The expression is as follows:

[0080] P = m*g*v*sina;

[0081] The required output power P1 of the traction motor is calculated based on the required locomotive climbing power P and the motor efficiency η. The expression is as follows:

[0082] P1=P / η;

[0083] Combined with the traction motor air volume-power-shaft temperature relationship curve under tunnel and non-tunnel conditions, the expected bearing temperature T under the current air volume and the required locomotive climbing power P is calculated.q , the specific calculation is as follows:

[0084] The temperature rise at the top of the slope is calculated based on the following formula:

[0085] T=k1*P1*L1 / v-k2*Q d +k3*t;

[0086] Among them, T is the temperature rise value at the top of the slope, k1, k2, k3 are empirical coefficients related to the vehicle model, Q d is the current air volume, and only t differs between tunnel and non-tunnel conditions;

[0087] Expected bearing temperature T under current air volume and required locomotive climbing power P q Calculated using the following formula:

[0088] T q =T0+T;

[0089] Where T0 is the temperature at the bottom of the slope;

[0090] Determine the T q Whether the preset alarm temperature is reached, that is, whether T q <120℃ and T q -t<80℃, no shaft temperature alarm will occur;

[0091] If T q ≥120℃ or T q -t≥80℃, an axle temperature alarm will occur.

[0092] Step 3: Calculate the variable conditions for preventing the occurrence of shaft temperature alarms, and adjust the fan operation strategy so that the subsequent traction motors do not have shaft temperature alarms. Step 3 specifically includes:

[0093] First, assume that the wind volume is the largest when climbing a slope. When the calculated result is T q ≥120℃ or T q -t≥80℃, the maximum air volume Q of the cooling fan max (This embodiment is 1.45m 3 / s, the maximum value varies for different fans) Recalculate T q , and judge the climbing process T q Check whether the alarm threshold is exceeded. If not, adjust the cooling fan frequency to the maximum frequency according to the current position and the climbing distance. When the distance L2 = 0, the cooling fan frequency is adjusted to the maximum frequency. When the alarm condition is not met, the air volume Q is appropriately reduced. d Repeat the above process until the alarm condition is just reached, that is, Tq = 120 or Tq-T0 = 80℃, then the air volume at this time is the minimum air volume Q without alarm. minThe data processing host is based on the relationship between fan frequency and air volume (measured in advance in the laboratory or operating circuit, built into the system, air volume Q = k7*f, and the maximum air volume Q max and minimum air volume Q min The frequency corresponding to a suitable air volume is sent to the control system, and the fan is controlled to run at a suitable frequency, so no alarm problem occurs.

[0094] Or increase the running speed appropriately until the calculated T q , just reaching the axle temperature alarm condition, then the speed at this time is the maximum allowable operating speed V max The data processing host outputs information to control the traction fan to run at a maximum frequency of 60Hz, and at the same time sends data to the driver's console display, suggesting that the driver should not exceed the maximum speed V max run.

[0095] If the cooling fan is running at maximum air volume or full frequency and still reaches the alarm condition, the maximum air volume Q max =1.45m 3 / s and preset alarm temperature T q =120℃ are the two parameters as the boundary, and the highest slope bottom temperature T0 without alarm is calculated by reverse calculation through the traction motor air volume-power-axis temperature relationship curve;

[0096] Combined with the current traction motor temperature T d , fan air volume or frequency, distance to the climbing position L2, based on the balance between heating and heat dissipation of the traction motor on flat or downhill roads, the expression is as follows:

[0097] δT=k5*P1*L2 / v-k6*Q d ;

[0098] Among them, k5 and k6 are empirical coefficients related to vehicle models;

[0099] Let T d -T0=δT, calculate the shortest distance L from the bottom of the slope under maximum wind volume 2min ;

[0100] According to the current position and the distance of climbing, when the distance L2=L 2min When the fan is running, adjust the fan frequency to the maximum frequency so that the shaft temperature alarm will not occur later;

[0101] When calculating L 2min >When the distance from the locomotive to the bottom of the slope is L2, let L2 = L 2min , according to δT=k5*P1*L2 / v-k6*Q d Calculate the speed v of the locomotive. If v>v min , v minis the minimum speed of the locomotive on this section, then immediately reduce the locomotive speed to v min , and adjust the fan frequency to 60Hz to ensure that no shaft temperature alarm occurs later;

[0102] When v <v min Even if the locomotive reduces its speed in time and is under the condition of maximum ventilation, an alarm will occur during the subsequent climbing. At this time, it is necessary to stop the vehicle and restart it when the traction motor temperature drops to the lowest temperature where no alarm will occur, so as to ensure that the locomotive will not have an axle temperature alarm.

[0103] In addition, after a locomotive has been running for a period of time, the blockage of the low-resistance louver filters often causes a decrease in air volume, affecting the heat dissipation of the motor bearings. In this embodiment, when the louvers are clogged, the system resistance increases. The monitoring system analyzes the air volume data at the same frequency to determine the blockage status. When the current fan air volume is only 90% of the original under the same tunnel or non-tunnel conditions and at the same frequency, that is, the louvers are approximately 10% clogged, the shaft temperature is predicted based on the air volume of the blockage. If the system predicts that the alarm will still occur even when the fan is running at maximum wind speed at the bottom of the ramp, the louvers must be cleaned and the current blockage status is set to critical. The system will then dynamically adjust the blockage status to enable maintenance and cleaning of the louvers.

[0104] Step 4: When the same route and operating conditions are common, the parameters in steps 1 to 3 are automatically recorded to form a database. When the same route and operating conditions are used, the axle temperature alarm is automatically controlled according to the database without recalculation, which improves the system decision time, ensures the correctness of the decision and reduces the time consumption of the decision.

[0105] This embodiment also includes a readable storage medium having computer program instructions stored thereon. When the computer program instructions are executed by a processor, the above-mentioned locomotive traction motor shaft temperature control method is implemented.

[0106] Exemplarily, the computer program may be divided into one or more modules / units, which are stored in the memory and executed by the processor to implement the present invention. The one or more modules / units may be a series of computer program instruction segments capable of implementing specific functions, and the instruction segments are used to describe the execution process of the computer program in the electronic device.

[0107] This embodiment also includes an electronic device, including: at least one processor, at least one memory, and computer program instructions stored in the memory. When the computer program instructions are executed by the processor, the locomotive traction motor shaft temperature control method as described above is performed.

[0108] The electronic device may be a computing device such as a mobile phone, desktop computer, laptop, PDA, or cloud server. The electronic device may include, but is not limited to, a processor and memory. For example, the electronic device may also include input / output devices, network access devices, buses, etc.

[0109] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A method for controlling the shaft temperature of a locomotive traction motor, characterized in that: include: Step 1: Obtain the bearing parameters of the locomotive traction motor and determine whether the bearing is abnormal. If abnormal, an alarm will be issued; if normal, proceed to the next step; Step 2: Obtain the current locomotive information, cooling fan operation information, environmental information, and line information. Use the axle temperature prediction method to calculate whether an axle temperature alarm will occur during the nearest climbing process under the current operating state. If no alarm occurs, continue operation according to the current state. If an alarm occurs, proceed to the next step. Step 3: Calculate the variable conditions for preventing the occurrence of shaft temperature alarms, and adjust the fan operation strategy so that subsequent traction motors do not have shaft temperature alarms.

2. The locomotive traction motor shaft temperature control method according to claim 1, characterized in that: The method for determining whether the bearing is abnormal in step 1 includes: Obtain vibration acceleration and temperature data of the bearings of the locomotive traction motor; Through data preprocessing and feature extraction algorithms, a bearing vibration characteristic state index is constructed to preliminarily judge the bearing vibration condition. If the characteristic state index H < 0.5, the bearing is judged to be normal. If the characteristic state index H ≥ 0.5, the vibration acceleration data is subjected to Fourier transform to calculate the characteristic frequency and obtain a spectrum diagram based on the vibration acceleration; Compare the spectrum diagram with the bearing fault frequency to determine the bearing fault type; The process of constructing the characteristic state index is as follows: first, based on the acceleration sensor data, characteristic values ​​including effective value, peak-to-peak value, high-to-low frequency energy ratio, kurtosis, impact decibel, and margin factor are calculated, one or more key features that best reflect the bearing state are selected from the characteristic values, and then the characteristic state index is constructed. The construction formula is: Where H is the constructed feature state index, x is the selected key eigenvalue, n is the number of eigenvalues, which is up to 13, w is the weight of each eigenvalue, and the subscript i = 123…n.

3. The locomotive traction motor shaft temperature control method according to claim 2, characterized in that: The second step specifically includes: Obtain the current locomotive gross weight m, vehicle speed v, ambient temperature t, cooling fan operating frequency f, traction motor temperature t1, slope length L1, slope a, and distance to the ramp L2; A shaft temperature prediction method is used to calculate whether a shaft temperature alarm will occur during climbing under the current situation. The shaft temperature prediction method includes: The climbing power P of the locomotive is calculated based on the locomotive gross weight m, speed v, and slope a. The expression is as follows: P = m*g*v*sina; The required output power P1 of the traction motor is calculated based on the required locomotive climbing power P and the motor efficiency η. The expression is as follows: P1=P / η; Combined with the traction motor air volume-power-shaft temperature relationship curve under tunnel and non-tunnel conditions, the expected bearing temperature T under the current air volume and the required locomotive climbing power P is calculated. q , the specific calculation is as follows: The temperature rise at the top of the slope is calculated based on the following formula: T=k1*P1*L1 / v-k2*Q d +k3*t; Among them, T is the temperature rise value at the top of the slope, k1, k2, k3 are empirical coefficients related to the vehicle model, Q d is the current wind volume; Expected bearing temperature T under current air volume and required locomotive climbing power P q Calculated using the following formula: T q =T0+T; Where T0 is the temperature at the bottom of the slope; Determine the T q Whether the preset alarm temperature is reached, that is, whether T q <120℃ and T q -t<80℃, no shaft temperature alarm will occur; If T q ≥120℃ or T q -t≥80℃, an axle temperature alarm will occur.

4. The locomotive traction motor shaft temperature control method according to claim 3, characterized in that: The step three specifically includes: When the calculation result is T q ≥120℃ or T q -t≥80℃, the maximum air volume Q of the cooling fan max Recalculate T q , and judge the climbing process T q Check whether the alarm threshold is exceeded. If not, adjust the operating frequency of the cooling fan to the maximum frequency according to the current position and the climbing distance. When the distance L2 = 0, adjust the operating frequency of the cooling fan to the maximum frequency. If the cooling fan is running at maximum air volume or full frequency and still reaches the alarm condition, the maximum air volume Q max =1.45m 3 / s and preset alarm temperature T q =120℃ are the two parameters as the boundary, and the highest slope bottom temperature T0 without alarm is calculated by reverse calculation through the traction motor air volume-power-axis temperature relationship curve; Combined with the current traction motor temperature T d , fan air volume or frequency and the distance from the climbing position L2, according to the balance between heating and heat dissipation of the traction motor on flat or downhill roads, the expression is as follows: δT=k5*P1*L2 / v-k6*Q d ; Among them, k5 and k6 are empirical coefficients related to vehicle models; Let T d -T0=δT, calculate the shortest distance L from the bottom of the slope under maximum wind volume 2min ; According to the current position and the distance of climbing, when the distance L2=L 2min When the fan is running, adjust the fan frequency to the maximum frequency so that the shaft temperature alarm will not occur later; When calculating L 2min >When the distance from the locomotive to the bottom of the slope is L2, let L2 = L 2min , according to δT=k5*P1*L2 / v-k6*Q d Calculate the speed v of the locomotive. If v>v min , v min is the minimum speed of the locomotive on this section, then immediately reduce the locomotive speed to v min , and adjust the fan frequency to 60Hz to ensure that no shaft temperature alarm occurs later; When v <v min Even if the locomotive reduces its speed in time and is under the condition of maximum ventilation, an alarm will occur during the subsequent climbing. At this time, it is necessary to stop the vehicle and restart it when the traction motor temperature drops to the lowest temperature where no alarm will occur, so as to ensure that the locomotive will not have an axle temperature alarm.

5. The locomotive traction motor shaft temperature control method according to claim 4, characterized in that: The step three also includes: Obtain normal air volume data at the same frequency to determine the blockage status of the low-resistance louver filter; Based on the blockage status and the variable condition that no axle temperature alarm occurs, determine whether an axle temperature alarm will occur when the fan at the bottom of the slope runs at the maximum wind speed. If an axle temperature alarm occurs, it is recommended to clean the low-resistance louver filter after the locomotive returns to the depot and set the current blockage status to a critical state.

6. The locomotive traction motor shaft temperature control method according to claim 5, characterized in that: The invention also includes step 4, wherein the step 4 includes: The parameters in steps 1 to 3 are recorded to automatically form a database.

7. A readable storage medium, characterized in that: Computer program instructions are stored thereon, and when the computer program instructions are executed by a processor, the locomotive traction motor shaft temperature control method according to any one of claims 1 to 6 is implemented.

8. An electronic device, characterized in that: include: At least one processor, at least one memory and computer program instructions stored in the memory, when the computer program instructions are executed by the processor, the locomotive traction motor shaft temperature control method according to any one of claims 1 to 6.

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