Shanghai Tongjie Technology Co., Ltd. is the largest and most powerful independent automobile design and engineering company in China and the earliest automobile design and engineering company in China. The company was established in 1999. After more than ten years of development, Tongjie has now achieved one-stop turnkey service from product creative design, engineering research and development, prototype trial production, experimental research to mold design and manufacturing, and supporting key parts. capabilities. The company has more than 80 domestic and foreign vehicle companies, including mainstream domestic and foreign automobile companies such as FAW Group, Dongfeng Motor Group, and SAIC Motor Group.
This project is the research and application of some key technologies for small electric vehicles. It is a key research project established by Shanghai Tongjie Technology Co., Ltd. It aims to solve outstanding problems encountered in the process of developing electric vehicles with independent intellectual property rights for domestic and foreign companies. Problems and difficulties. Small electric vehicles refer to vehicles that are powered by on-board power supply and use motors to drive the wheels, and meet the requirements of road traffic and safety regulations.
Its drive motor adopts a DC brushed or AC asynchronous motor, which has low cost and high cost performance. At the same time, there are forward gears and reverse gears for easy operation and driving. Small electric vehicles, like ordinary drivers, can carry 4-5 people and can drive on national B-class roads. Battery packs generally come standard with low-cost lead-acid batteries, and high-performance and high-capacity lithium batteries are available as optional. In the chassis system, the front suspension is a McPherson independent suspension, and the rear suspension is a trailing arm type non-independent suspension with tie rods. The ride comfort and stability of the whole vehicle are considered in the design.
Because electric vehicles use electric motors as driving components, their driving system, operating system, body structure and energy storage system are quite different from traditional vehicles. If traditional design ideas are still adopted for electric vehicle design, it will bring greater difficulties to the design work. During the research and development of this project, we combined the practical work experience of various electric vehicle designs, systematically summarized the technical problems of electric vehicle design, conducted research and key research, and proposed practical solutions. The main contents are summarized as follows:
1. Lightweight body design. In terms of structural design, the structural topology is optimized and the number of parts is reduced. In terms of material selection, the selection proportion of high-strength steel plates is controlled through failure optimization methods. On the premise of meeting the body performance indicators, the body has the lightest weight and the lowest cost. In terms of process control, the stamping rebound characteristics are used to reduce the stamping process of parts.
2. Modular design of battery system. The battery pack is divided into two parts: the main battery pack and the auxiliary battery pack. The main battery pack adopts the same packaging structure and matches the quick-assembly structure design. The electrical interface adopts a universal design. It can realize universal use of main battery pack modules for different models and quick installation and quick replacement of main battery packs. It can match the front and rear axle loads to 50%: 50%, achieving the theoretical optimal driving characteristics;
3. Safety optimization design of electric vehicle electrical systems. Consider the actual characteristics of the electronic control system, high and low voltage electrical system, the electrical system under normal use conditions, accident conditions, and maintenance conditions in the design, and achieve and realize the safe design of the electrical system through designing safety warning signs, testing critical safety conditions, isolating specific electrical appliances, etc. Technical means;
During the project development process, we overcame the technical difficulties that occurred in the project and successfully completed the project expectations. This project has a total of 11 utility model technology patents, has applied for 1 invention patent, and has passed 4 technical novelties and 1 scientific and technological consultation report. The above technological innovations are industry-leading. After adopting the above technological innovations in this project, the overall performance of electric vehicles has been improved, the development range of electric vehicles has been increased, the electrical failure rate of electric vehicles has been reduced, and the after-sales maintenance time of electric vehicles has been reduced.
This innovative technology has been used in eight electric vehicle research and development projects in five electric vehicle main engine factories, of which two electric vehicles have completed mass production and are on the market.