Topic: permanent magnet synchronous motor for electric vehicle and its control system
First, the purpose of this project design:
1. Understand the development status and future development trend of electric vehicles.
2. Learn the related knowledge of electric vehicle drive system, master the mathematical model of permanent magnet synchronous motor and the mainstream control strategy of permanent magnet synchronous motor control system.
3. The control principle and method of permanent magnet synchronous motor for electric vehicle are deeply studied, and the control process is simulated by simulation software.
4. Using matlab/simulink software, the primary control system of permanent magnet synchronous motor is established, including hardware and software, and the simulation experiment is carried out.
Second, the project status and development trend:
At present, the development status of automobile permanent magnet motor: (1) The permanent magnet synchronous motor drive system has formed a certain R&D and production capacity, and developed different series of products, which can be applied to various electric vehicles; Some technical indicators of the products are close to the international advanced level, but there is still a certain gap between the overall level and foreign countries; Basic comprehensive design ability of permanent magnet synchronous motor; Most companies are still in the stage of small-scale trial production, and a few companies have invested in the establishment of special production lines for vehicle drive motor systems. (2) The position/speed sensor used in the motor controller, the key components of the motor controller, are mostly rotary transformers, which are basically imported at present. Some domestic companies already have the R&D and production capacity of resolver, but there is still a gap with foreign countries in product accuracy and reliability. IGBT basically depends on imports and is expensive. IGBT for domestic vehicles is still in the research stage.
The main problems of drive motors and their controllers in China are: (1) The research and development ability of motor raw materials and core components of controllers is weak, and they rely on imports, such as silicon steel sheets, motor high-speed bearings, position/speed sensors, IGBT modules, etc. The high cost of imported products affects the industrialization of motor system. (2) There is a big gap between the electromechanical integration level of automobile motors in China and foreign countries. The controller is more integrated.
Low, relatively large in volume and weight. (3) At present, there are few and imperfect national standards for electric vehicle drive motor system. For example, different types of motor systems adopt the same test standards, lacking reliability and durability evaluation methods.
The development trend of vehicle motor and control system is as follows: (1) Permanent magnet of motor body: Permanent magnet motor has the advantages of high torque density, high power density, high efficiency and high reliability. China has the richest rare earth resources in the world, so high-performance permanent magnet motor is an important development direction of vehicle drive motor in China. (2) Digitization of motor control: The appearance of special chip and digital signal processor promotes the digitalization of motor controller, improves the control accuracy of motor system and effectively reduces the system volume.
(3) Motor system integration: Through electromechanical integration (motor and engine integration or motor and gearbox integration) and controller integration, the weight and volume of the drive system can be reduced, and the manufacturing cost of the system can be effectively reduced.
Three. Key points, difficulties and methods of design;
(1) The key and difficult points of the project design are: 1, learning and analyzing the advantages of automobile permanent magnet synchronous motor; 2. Learn the mathematical model of permanent magnet synchronous motor; 3. Analyze the optimal control strategy according to the mathematical model of permanent magnet synchronous motor; 4. The control system is established by matlab/simulink and simulated.
(2) The way to break through the difficulties: 1. Consult the relevant literature, and study and understand the permanent magnet synchronous motor systematically and deeply; 2. Learn the use of matlab/simulink software and master it thoroughly through computer practice.
Fourth, the design progress:
The project design is mainly divided into three stages:
The first stage: 1, review the relevant knowledge of permanent magnet synchronous motor, and consult the materials to learn the advantages of permanent magnet synchronous motor; 2. Learn the mathematical model of permanent magnet synchronous motor, summarize its characteristics and feasible control methods; 3. According to its mathematical model, the differences between different control strategies are studied, and the optimal control strategy is found.
The second stage: learning the use of matlab/simulink software.
The third stage: Combined with the previous research, the software and hardware of the simple permanent magnet synchronous motor control system are designed.