CN-122017552-A - Electric control method and system for real-time monitoring of dangerous point position of motor rotor

CN122017552ACN 122017552 ACN122017552 ACN 122017552ACN-122017552-A

Abstract

The invention provides an electric control method and system for monitoring dangerous point positions of a motor rotor in real time, wherein the method comprises the steps of collecting simulation data of the motor rotor service of a new energy automobile under different working conditions, constructing a simulation data base, and obtaining simulation results of the rotor service under a multi-damage and multi-load coupling state; the method comprises the steps of identifying dangerous point positions of a rotor according to simulation results, building a dangerous point position prediction model based on a deep neural network by utilizing simulation data accumulation of the dangerous point positions, collecting rotor service data in a target new energy automobile motor in real time through an electric control system, preprocessing working condition data, inputting the working condition data into the dangerous point position prediction model to obtain single-cycle damage data, carrying out real-time damage normalization state monitoring according to the Shan Zhouci damage data, and automatically triggering early warning in response to the fact that damage exists or is about to exist in the dangerous point positions.

Inventors

ZHANG XINHAO
ZHANG DI
LIU YUCHENG
LEI ZHENGYU
XU HUA
ZHONG CHENG

Assignees

合肥轾驱新能源有限公司

Dates

Publication Date: 20260512
Application Date: 20251212

Claims (10)

1. An electric control method for real-time monitoring of dangerous point positions of a motor rotor is characterized by comprising the following steps: collecting simulation data of the service of the motor rotor of the new energy automobile under different working conditions, constructing a simulation data base, and obtaining simulation results of the service of the rotor in a multi-damage and multi-load coupling state; Identifying dangerous point positions of the rotor according to the simulation result, and building a dangerous point position prediction model based on a deep neural network by utilizing simulation data accumulation of the dangerous point positions; acquiring service data of a rotor in a target new energy automobile motor in real time through an electric control system, preprocessing the working condition data, and inputting the preprocessed working condition data into the dangerous point part prediction model to obtain single-cycle damage data; and carrying out real-time damage normalization state monitoring according to the Shan Zhouci damage data, and automatically triggering early warning in response to the detection that the damage exists or is about to exist at the dangerous point.
2. The electric control method for real-time monitoring of dangerous point positions of a motor rotor according to claim 1, wherein the simulation data are different physical information parameter combinations obtained by physical sensing of the rotor in the service process of the motor of the new energy automobile, and the physical information parameter combinations comprise, but are not limited to, centrifugal force fatigue damage data and single-cycle vibration damage data obtained by elastic finite element analysis, and plastic/creep damage data of interference effect obtained by temperature field finite element analysis.
3. The electric control method for real-time monitoring of dangerous point positions of a motor rotor according to claim 1, wherein the step of identifying dangerous point positions of the rotor according to the simulation result comprises the following steps: and according to the simulation result, screening the part or the node with the maximum damage value of multi-damage and multi-load coupling in Shan Zhouci as a dangerous point part through quantitative analysis of the damage value.
4. The electric control method for real-time monitoring of dangerous point positions of a motor rotor according to claim 1, wherein the method for real-time collecting rotor service data in a target new energy automobile motor through an electric control system comprises the following steps: The electronic control system adopts dynamic sampling frequency logic to collect working condition data, namely rotor service data including but not limited to working condition data, respectively adopts different sampling frequencies in a motor starting stage, a steady-state stage and a closing stage, and utilizes the electronic control system to collect the rotor service data in real time through a CAN/LIN bus or a special sensor interface; The working condition data comprise, but are not limited to, working condition parameters of initial temperature, rising rotation rate, rising load rate, rotating speed, torque, shaft power and axial tension of the rotor under each cycle, wherein one cycle is a service process from a starting stage to a steady-state stage and from a steady-state stage to a closing stage when the rotor in the target new energy automobile motor is completed once.
5. The method for electronically controlling real-time monitoring of dangerous spot positions of a motor rotor according to claim 4, wherein the steps of sampling at different frequencies during a motor start-up phase, a steady-state phase and a shut-down phase respectively comprise: The starting stage is set to be 0-30s for rotor starting, the sampling frequency is set to be 100Hz, the rotating speed fluctuation is set to be less than or equal to 5% in the steady-state stage, the sampling frequency is reduced to be 20Hz, the rotating speed is reduced to be 0 in the closing stage, and the sampling frequency is 80Hz.
6. The electric control method for real-time monitoring of dangerous point positions of a motor rotor according to claim 1, wherein the preprocessing of the working condition data comprises, but is not limited to, data cleaning processing, data filtering processing and standardization processing, wherein the data cleaning processing comprises, but is not limited to, outlier elimination and deficiency complement, and the data filtering processing comprises, but is not limited to, filtering processing by using a limiting filtering method, a first-order lag filtering method, median filtering and Kalman filtering.
7. The method for controlling the electric control of the real-time monitoring of dangerous spot positions of a motor rotor according to claim 1, wherein the real-time damage normalization state monitoring is performed according to the Shan Zhouci damage data, and the early warning is automatically triggered in response to the detection of the existence or imminent existence of damage of the dangerous spot positions, comprising the following steps: Acquiring a real-time accumulated damage value of a weak point part under the current cycle by using a multi-element linear damage accumulation method; Setting a one-level or multi-level damage threshold, and triggering the whole vehicle alarm by the electric control system through a hardware signal or a bus message when the real-time accumulated damage value reaches the damage threshold.
8. The electric control method for real-time monitoring of dangerous point positions of a motor rotor according to claim 7, wherein the setting of the multi-stage damage threshold comprises setting a two-stage damage threshold, the two-stage damage threshold comprises an early-warning stage damage threshold and a fault stage damage threshold, the early-warning stage damage threshold is 0.8-0.95 times of rotor design life, and the fault stage damage threshold is greater than or equal to 0.95 times of rotor design life.
9. The electric control method for real-time monitoring of dangerous point positions of a motor rotor according to claim 7, wherein the multi-element linear damage accumulation method specifically comprises the following steps: according to the Shan Zhouci damage data di, the accumulated damage value D at the current moment of the current cycle N is accumulated and calculated through the following formula; wherein D is the accumulated damage value at the current moment, Is a single-cycle vibration fatigue damage, Is vibration fatigue damage, For plastic or creep damage, N is the cycle number of the high-temperature rotor at the current moment, i is the cycle number, di is single-cycle damage data, and Xi is the pretreated working condition data under the service working condition corresponding to the cycle number.
10. An electronic control system for real-time monitoring of dangerous point positions of a motor rotor, which is characterized by comprising: the simulation data acquisition module is used for acquiring simulation data of the service of the motor rotor of the new energy automobile under different working conditions, constructing a pure simulation data base and obtaining simulation results of the service of the rotor in a multi-damage and multi-load coupling state; The model construction module is used for identifying dangerous point positions of the rotor according to the simulation result and constructing a dangerous point position prediction model based on the deep neural network by utilizing simulation data accumulation of the dangerous point positions; The damage data acquisition module is used for acquiring service data of a rotor in a target new energy automobile motor in real time through an electric control system, preprocessing the working condition data, and inputting the preprocessed working condition data into the dangerous point part prediction model to obtain single-cycle damage data; And the real-time monitoring and early warning module is used for carrying out real-time damage normalization state monitoring according to the Shan Zhouci damage data, and automatically triggering early warning in response to the detection that the damage exists or is about to exist at the dangerous point.

Description

Electric control method and system for real-time monitoring of dangerous point position of motor rotor Technical Field The invention relates to the field of new energy automobile motors, in particular to an electric control method and system for monitoring dangerous point positions of a motor rotor in real time. Background In the field of new energy automobiles, a motor is used as a core power component, and the performance of the motor directly relates to the power performance, economy and reliability of the whole automobile. The connection quality of the motor rotor and the shaft plays a decisive role in the stable operation of the motor. At present, an interference fit mode is widely adopted in the industry to realize connection of a motor rotor and a shaft. The connecting mode has the advantages of simple structure, good centering, strong bearing capacity and the like, and can effectively ensure the NVH (noise, vibration and harshness) performance of the motor in the running process. However, in actual operating conditions, the interference fit of the motor rotor to the shaft presents a number of complex challenges. When the new energy automobile runs, the motor rotor rotates at a high speed, and a strong centrifugal force can be generated. Taking a high-speed permanent magnet synchronous motor with the peak rotation speed of 20000r/min as an example, the influence of centrifugal force on the interference fit between a shaft and an iron core is very remarkable. Under the action of the centrifugal force for a long time, the interference fit is easy to loosen, so that the dynamic balance of the rotor is further caused to deteriorate, abnormal vibration and noise are generated when the motor operates, and even the motor is caused to fail when the motor is serious. Meanwhile, in the running process of the new energy automobile, the motor can bear continuous vibration load due to factors such as road surface jolting and the like. This vibration causes a small relative displacement between the interference fit surfaces, which causes fretting wear. Over time, fretting wear can be gradually increased, so that the material of the matching surface is damaged, the matching precision is reduced, and the connection reliability is greatly reduced. And, heat is generated when the motor is operated, resulting in an increase in the temperature of the rotor and the shaft. Under the high-temperature environment, the mechanical property of the material can change, and a creep phenomenon is generated. This may cause a gradual decrease in the interference of the interference fit, further impairing the stability of the rotor to shaft connection. Numerous attempts have been made in the industry to solve the above problems. Part of enterprises expect to improve the performance of the motor shaft and rotor core under complex working conditions by optimizing the materials of the motor shaft and the rotor core. For example, a specific composite material is coated on the outer surface of the motor shaft, and the gap between the rotor core and the motor shaft is changed along with the temperature by utilizing the difference of the thermal expansion amounts of different materials so as to maintain the stability of interference fit. However, the method has extremely high requirements on material selection and coating process, high cost, and limited effects by various factors, and is difficult to widely popularize and apply. There have also been attempts by the industry to improve the assembly process, such as the use of a shrink fit process to enhance the strength of the rotor core to shaft connection. However, when the large-sized motor lacks large-sized pressure equipment due to the oversized rotating shaft, the problems of 'climbing shaft' of an iron core and the like easily occur when the hot sleeve shaft process is implemented, and the operation failure of the motor is caused. At present, although research and improvement measures aiming at interference fit of a motor rotor and a shaft exist partly, obvious defects still exist when the damage problem under complex working conditions is solved. The prior art can not accurately identify damage dangerous points at interference fit positions in real time, and is difficult to realize real-time monitoring and early warning of the running state of the motor. Once the motor fails, the motor can be maintained only after the accident, which not only causes the shutdown of the vehicle and brings great inconvenience to users, but also can cause high maintenance cost, thereby severely restricting the development of the new energy automobile industry. Therefore, a high-efficiency and convenient technical scheme is urgently needed, the accurate identification and real-time monitoring of the damage dangerous point position are realized, and the safe and stable operation of the motor is ensured. Disclosure of Invention In order to overcome the technical defects, the invention aims to provide the