Simulation study on the membership functions of the basic fuzzy logic controller for electric vehicle propulsion systems

Using the classical mathematical analysis methods, this paper presents a principle to select its membership functions for the basic fuzzy logic controller. The results of the analysis illustrate that the basic fuzzy logic controller actually is an equivalent nonlinear classical proportional regulator with variable parameters. For a zero steady-state step error system, a pure integrator should be added to the output of the basic fuzzy logic controller. The computer simulation results using the proposed principle on an electric van propulsion control system are presented in this paper.