A Study of the Dynamic Processes of a Starter-Generator by the Electrical Analogy Method

Abstract

The dynamics of a single-machine starter-generator unit, where the oscillatory regime occurs with the moment variation, is studied. The dynamic process calculation is performed with the use of differential equations. The mathematics analysis is presented. The basic relationships, used in the calculations of the static moments, forces and inertia moments, are considered. The present system motion equation is derived with the use of d`Alembert`s principle. The system of the equilibrium equation and the angular coordinate dependent differential equation is composed for the «starter-generator – crank shaft» calculation system. The electrical analogy method is used for deriving the equation of the torques applied to the same shaft. The angular frequency of revolution is determined by the equivalent circuit of the single-mass mechanical unit and the mechanical chain equivalent circuit in terms of the moment of rotation and the complex mechanical resistance, specified for the four-mass system. Then the process of the system transformation to the two-mass system is considered. The analytical expression for the resonance frequency is determined. The time variation of the parameters in the starter regime is considered in the Simulink program of the MATLAB software package.