Abstract: Electric Power Steering (EPS) is a new type of power steering system developed with the continuous development of electronic technology and computer technology. The main advantages of the electric power steering system are small footprint, high operating efficiency, no pollution and easy control, so the electric power steering system is increasingly applied to various types of motor vehicles. The main content of this paper is the design and development of the electric power steering system of electric forklift based on single chip microcomputer. The completed work and research results are briefly summarized as follows:1. The basic structural composition and dynamic model of the electric forklift EPS system are given. On this basis, the basic principle of EPS system of electric forklift is expounded. The difference between EPS system of electric forklift and EPS of ordinary car is analyzed. The main work of EPS system of electric forklift is determined by combining the actual working environment and working characteristics of electric forklift. Mode; at the same time, some key factors affecting the performance of EPS system of electric forklift are also discussed briefly. 2. Since the permanent magnet brushless DC motor is simple in structure, reliable in operation, and has good mechanical and dynamic characteristics, it is determined that the permanent magnet brushless DC motor is used as the assist motor in the development of the EPS system of the electric forklift; the control of the assisted motor In terms of strategy, the double-closed loop control mode of the outer speed loop and the inner current loop is used to apply the fuzzy loop and the current loop of the outer loop of the current hysteresis loop control system respectively; the MATLAB/Simulink environment is completed forever. The simulation model of magnetic brushless DC motor is built, and the simulation results are compared and analyzed. The causes of torque ripple of permanent magnet brushless DC motor are briefly introduced. The reasonable pulsation is proposed to suppress the torque ripple and improve the performance of the whole EPS system. In order to improve the response sensitivity and response of the EPS system of electric forklift Speed, using the control strategy of assist compensation; in order to obtain better power-assisted effect, the parabolic power assist characteristic curve was determined; the whole electric forklift EPS system was modeled and simulated by MATLAB/Simulink, and the simulation results were in good agreement with the expected results. , thus verifying the effectiveness of the control strategy. The C8051F340 single-chip microcomputer is used as the microcontroller of the electric forklift EPS system. The design of related hardware circuits and software programs is completed, and the related hardware logic circuit principle and software program flow are briefly introduced. 5. The steering process experiment, the assisting characteristic verification experiment and the assist compensation control experiment of the electric forklift EPS system were completed on the relevant experimental platform. The analysis of the experimental results shows that the electric forklift EPS system established in this paper has a good steering. Performance, which further validates the effectiveness of the entire control system. In summary, this paper is a detailed introduction to the development and design of the EPS control system for electric forklifts. From the initial theoretical analysis to the later modeling and simulation to the final field test, the idea is clear and the whole process is basically The requirements for the scheduled design task are completed, which has certain reference value for the actual engineering application.
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