The system for electric vehicle slippage prevention based on a fuzzy logic controller

Abstract

Purpose. Development of a functional diagram of a slip prevention system, build a mathematical model, synthesize a fuzzy regulator, simulate and confirm the system's performance. Methodology. Mathematical analysis and modeling. Findings. The structure is substantiated and the linguistic variables of the fuzzy regulator are determined. The choice of the number of terms of the input and output variables of the fuzzy controller is made, proceeding from the minimization of the number of logical processing rules. The terms of the linguistic variables of the fuzzy controller are selected in the form of the simplest triangular for the mean values of the range of their definition and trapezoidal for the limit values. Logical processing rules were developed. The choice of the fuzzy inference algorithm was made and the defuzzification parameters were determined. A computer model of the slip prevention system was built using the Fuzzy logic toolbox of the MATLAB package and was framed using 9 logic processing rules. Computer simulation of the acceleration of an electric vehicle with subsequent slipping by one and two wheels has been carried out. The system maintains the inconsistency of wheel speeds with the electric vehicle speed at a constant set level of 1.5s-1 - in accordance with the formulated identification algorithm and completely prevents excessive slipping. Originality. The built-in phase regulator ensures minimization of the discrepancy between the speed of the wheel rotation and the linear speed of the electric vehicle, which in turn minimizes slippage and provides the maximum possible torque relative to the moment of installation. Practical value. Computer simulation was carried out for two modes: acceleration with a collision with a surface with a reduced coefficient of adhesion (0.1) with one wheel and acceleration with a collision with a surface with a reduced coefficient of adhesion (0.1) with two wheels. The system completely prevents excessive slipping.