Modelling of a car starter with permanent magnet commutator motor
Purpose - The purpose of this paper is to present a developed modelling method of a car starter with permanent magnet commutator motor. Design/methodology/approach - Mathematical model, algorithm and computational program of electrical and mechanical quantities transients in the system: battery - car starter with permanent magnet commutator motor and planetary gear - combustion engine were developed. Circuit-field method was applied. Magnetic quantities determined using time-stepped finite-element method (with the help of Maxwell software) were used as the parameters of mathematical model equations in circuital part. Program was developed in the Matlab environment. Findings - The developed mathematical model, the algorithm and the program enable the computations of transients of electrical and mechanical quantities at different ambient temperature, by different swept capacity of the combustion engine as well as by different battery capacity and different charge ratio. Research limitations/implications - The analysis was carried out on an example of four-cylinder combustion engine. However, the developed modelling method can be used for analysis of different combustion engines start-up. Practical implications - The proposed modelling method is useful for analysis of car starters at the stage of design. Originality/value - The originality of the work consist in the fact that in the developed model variation of the car starter load torque as well as the variations of the entire mechanical system moment of inertia were taken into account.
modelling cars electrical machines reciprocating engines