Research On Controller Of Power Steering System For All Terrain Vehicle

Electric power steering (EPS) system with energy saving and environmental protection and excellent steering performance in a variety of models of the assembly rate continues to improve. All terrain vehicle is widely used in forestry, agriculture, exploration and military fields, because of its multi driving to the beach, potholes and mountain complex terrain, there are heavy steering and easy to produce fatigue driving. Research on the key parts controller of the electric power steering system of all terrain vehicle, which is helpful to improve the steering feel and brand competitiveness of all terrain vehicle.In order to study the feasibility of the electric power steering system on the all terrain vehicle. According to the parameters of the vehicle, the speed and the output torque of the motor are calculated. According to the all terrain vehicle emergency avoidance condition and steering portability requirements calculation speed reducer gear ratio. The force analysis of the rocker type steering system and the assistant motor of the whole terrain vehicle, and the Simulink simulation model is established. The improved power characteristic curve for all terrain vehicle is analyzed and designed. The curve fitting method is used to explain the curve establishment process. A compound fuzzy PID control algorithm is designed. The vehicle and subsystem model established by Carsim and the Simulink model are combined to simulate the effectiveness of the control strategy.Around the needs of all terrain vehicle power steering. Based on Designer Altium, the DSP main control unit, LIN communication, power supply processing conversion and signal acquisition and processing circuit are designed. The drive and H bridge circuit is used to realize the bidirectional rotation of the power assisted motor. Based on Multisim, taking the power supply circuit of the sensor as an example, the simulation calculation process is illustrated. Based on the modular design idea, the AD and ICx modules are configured based on the MPLAB platform. The arithmetic mean filter method and recursive average filter method are used to filter the signal. The algorithm and the compound fuzzy PID algorithm are designed. The P WM output signal is configured according to the bipolar control mode. Use of power on self test and real-time monitoring of fault program to protect the safe operation of the system.In order to carry out the software and hardware connection, the all terrain vehicle steering system simulation platform is built. The limit power consumption, the bipolar control effect, the controller power assist tracking and response speed of the EPS controller are tested. In order to obtain the actual output data, the input torque/motor current characteristics and input /output torque characteristics were tested by using the comprehensive performance test rig. The parameters such as the maximum power current, the curve symmetry, the characteristic of the speed, the maximum output torque and the torque fluctuation are obtained. Combined with the real vehicle test, this paper shows that the design of all terrain vehicle EPS controller to control the power output size to meet the requirements,and steering process feel smooth. Provides a foundation for the assembly of EPS in all terrain vehicles,and it is helpful to improve the performance of the all terrain vehicle steering system.