The modern automobile steering system has developed from the initial mechanical steering, hydraulic power steering (power steering hydraulic, HPS) to the electric power steering (power steering electrical, EPS) technology. With the wide use of micro electronic control technology in the automotive field, as well as the promotion of the world's two major topics of energy saving and environmental protection, the superiority of EPS is becoming more and more prominent, and become the focus of the research of turning technology.
In recent years, in order to conform to the trend of the development of automotive energy-saving environmental protection, electric power steering system of more rapid development and application is more and more widely: from the original mini car to larger cars and commercial vehicles of the direction of development. EPS's power type also from the low speed range of power to full speed range of power development, and its control form and function is further strengthened. Japan's early EPS only in the low speed and parking to provide power, high speed EPS will stop working. The new generation of EPS is not only in low speed and parking to provide power, but also at high speed to improve the control of the vehicle stability. Such as the SUZUKI company is equipped in the r+ wargon car on the EPS is a load - Road - speed induction type power steering system.
Due to the power limitation, the present EPS is suitable for passenger car, which is not suitable for commercial vehicle. EPS system in the Chinese market is very large, compared to HPS, more fuel economy. EPS is being favored by Chinese consumers and auto makers, and EPS is also an important configuration for those who want to export to Europe and Japan. At present, EPS has been applied in more and more vehicles, these cars not only from to the Japanese and European brands, but also from the Chinese local brands, including A3 and Chery QQ, Geely steels and vision, Changan Benben, Xiali N3.
China electric power steering system market, foreign or joint ventures accounted for a monopoly position. Currently the Japanese Jtekt (Jtekt) Germany ZF ZF), Japan Seiko (NSK), TRW (TRW) and other global steering system vendors have launched electric power steering system and attracted by the huge market demand in China, have been in China design production base. Jtekt is the world's largest supplier automotive steering system, by the end of February 2012, the company in China has a total of seven steering system production base, which has four production bases in the production of the electric power steering system.
The local Chinese appeared in a number of EPS production enterprises, for example, in northern Xinxiang, easy force of energy-saving and other enterprises. Which is easy to be reached in 2001 developed China's first with independent intellectual property rights of electric steering system, at present the company has a total of two electric power steering system assembly production lines, and China FAW, Changan, China China Dongfeng several car factory established matching relationship.
The senior auxiliary steering system main characteristic is the function of automatic collision avoidance. The suddenly broke into a person or vehicle, only by the driver brakes and steering, probably cannot be completely avoided, and sensor will first time aware of the danger, the system will quickly correct self driving cars to avoid the collision. And, after the completion of the emergency avoidance risk, in order to ensure the normal running of the automobile and steering, the system will automatically reversing the steering wheel, the car quickly restored to a safe driving condition.
EPS important function is an electric vehicle deceleration maximum energy recovery to the battery "regenerative braking system", and it is used by many car can avoid collision "auto brake system. In order to achieve these functions, compared with the previous braking system, the internal structure of the system is more sensitive, smaller, lighter in weight. NSK in the world for the first time successfully developed a lightweight, low energy consumption of the car EHB ball screw, to improve system efficiency, reduce power consumption can play an important role.