New energy vehicles drive motor for bearing the challenge!

New energy vehicles drive motor for bearing the challenge! 2020 - 05 - 08 01 type and characteristics of new energy vehicles drive motor dc motor advantages: mature technology, easy control, good speed regulation cons: mechanical complexity limited, instantaneous overload capacity and motor speed increase, high frequency electromagnetic interference three-phase ac asynchronous motor advantages: simple structure, good reliability, the cost of a manageable disadvantages: low efficiency, poor speed permanent magnet synchronous motor advantages: high power density, quick response speed disadvantages: high temperature and overload current demagnetization occur switched reluctance motor advantages: simple structure, wide speed, fast response disadvantages: large noise, power density, low usage efficiency, permanent magnet synchronous motor (80%), including: Beijing auto, byd, saic, jianghuai passenger car; Xiamen golden dragon bus three-phase ac asynchronous motor (18%), including: tesla ModelS and other ModelS; Yutong, zhongtong coach switched reluctance motor (2%) of dongfeng hybrid buses, etc. High power density permanent magnet synchronous motor, large range of speed regulation, and is suitable for frequent start-stop condition; Three-phase ac asynchronous motor unit power of low cost, no demagnetization, apply to the operation condition of the highway system developed. 02 technical requirements of the driven motor with high torque low speed high torque runtime, to meet the requirements of quick start, acceleration, climbing and so on should be high speed running at a high speed high speed, wide speed range and features, to meet the requirements of high-speed, overtaking and high efficiency and energy saving electric cars frequent start-stop, work area wide, therefore, request as wide as possible efficient workspace, in mileage for battery after a charge as long as possible vibration resistance, resistance to vibration motor has certain overload ability, under different conditions can work stably and reliably 03 drive motor to motor bearing the challenge the general industrial use of motor bearing, the domestic bearing industry through constant development, with the improvement of bearing design theory, the bearing steel material technology advances, ring to raise the level of processing equipment, process of steel ball manufacturing level up the steps, has replace imported occupied the domestic major markets, but the car drive motor, wide speed range and large starting torque, high power density, high efficiency characteristics, make it to the bearing of high speed, high and low temperature, durability, stability, reliability, put forward the higher request, the current domestic new energy automobile motor bearing is still mainly rely on imports. Speed drive motor speed 20000 r/min, bearing the dm. The n value above 800000, motor speed is much higher than the general industry. The temperature - 40 ~ 150 ℃ bearing stable running, without the noise; The long-term working temperature of 110 ~ 120 ℃; Start the temperature - cold area 30 - - 20 ℃, small starting torque, low noise. For low temperature grease lubrication performance, high temperature resistant, resistant to vibration and energy saving efficiency and long life. Vibration and noise in order to ensure the ride comfort, the vibration of the motor is lower noise level, ensure that the car's quiet. Electric erosion caused by winding unbalanced, there is a potential difference between the rotor and a current; Inverter high-frequency voltage caused by the leakage current may result in bearing produce electric erosion, lead to the failure of the bearing. Lifetime guarantee with the vehicle warranty 5 - long life 8 or 10 - 160000 kilometers. 04 bearing enterprises to make measures to face new challenges, new application field for bearing need to do a lot of effort for the industrialization of the independent research and development to: improve purity of steel and heat treatment quality; Using precision grinding technology, improve machining precision and reduce the product batch discrete degree; Study on the lubrication, and lubrication enterprise cooperation development to adapt to the high temperature and high speed of lubrication products; Choose appropriate engineering plastic cage; Using experiment and simulation technology, speed up the development, to guarantee the credibility of bearing, and so on. International famous bearing enterprises put forward countermeasures for our reference. EDrive ball bearing series, SKF developed through optimizing design of raceway, the design structure of new type polymer cage, the grease of wide temperature range and design of the hybrid ceramic bearing, able to adapt to the performance of high-speed motor bearing helps to prolong the service life of the transmission system and expand the range of the battery. NSK USES excellent heat resistance of resin material, by keeping frame strength analysis of shape optimization design, so as to reduce the centrifugal force, reduce the friction between cage and steel ball, lower calorific value; Using high-speed grease, choose the most suitable thickening agent, can be in a wide range of temperatures lower calorific value; The use of special treatment, in the steel ball surface precipitation high hardness nitrides, improve sintering resistance, thus improve the performance of high speed; Using non-contact rubber seal, inhibit leakage of grease from a work, guarantee the reliability of the bearing running; Set the o-ring on the surface of the outer diameter, reduce the gap with a hole, improve the creep resistance. （ Source: the journal bearing)