The Research On Double Pumps EHPS For In The Electric Bus

Energy-saving, environment protection and safety are the development trend of automotive technology nowadays. Electric bus has become the hot pot of the Government and community because of its energy-saving and environmental advantages. In order to be more energy-efficient and safe in EHPS system on electric bus, we developed a new type of double motors drive steering pump EHPS system. The EHPS system which is driven by double motors and double pumps was reached in the paper, and a lot of work was done as follows.1) By studying the electric bus steering system structure, the electric bus steering resistance and the maximum power were calculated. We selected the type of steering pump, double motors and driving connection to meet the main capacity of the steering pump and driving motors. Besides, the structure of the double-pumps EHPS had been designed.2) Based on analyzing the operating principle of the double-pumps EHPS, the mathematic model was created. With the designate parameters such as the rotate speed and the torque, we finished the simulation model and got the conception that compared with the traditional EHPS, the new system have better response speed and power.3) The current controller and the rotate speed controller were used for the double PI control. Besides, the control strategy of the word condition for the two motors had been designed.4) Analyzing the consumption of the double-pumps EHPS, we gave the solution to deal with the energy loss on the machinery component, circuit and hydraulic sector.5) The assist power test and the durable ability test had been done to proof the correctness of the conception above.