COMPARATIVE ANALYSIS OF THE ENERGY INDICATORS OF SINGLE-MOTOR AND MULTIPLE-MOTOR ASYNCHRONOUS ELECTRIC DRIVE
The aim of the work is to conduct a comparative analysis of single-engine and multi-engine asynchronous traction electric drive based on energy based on the assessment of energy losses in traction asynchronous electric motors of different power using the proportional law of frequency control to control the speed of traction asynchronous electric motors in the first zone. The energy loss analysis in traction asynchronous electric motors was carried out for three values of the voltage frequency on the stator winding 50 Hz, 25 Hz and 12.5 Hz and for three values of the total load moment corresponding to the full, half full and empty bus on the asphalt road. In determining the total load moment, the rolling resistance of the bus and the air resistance were taken into account. As a result of the analysis, a formula was obtained that allows, based on the power of constant and variable losses in compared electric motors corresponding to the nominal load moment, to determine the number of low-power engines that make up the multi-motor drive, which will provide the energy effect from the use of multi-motor electric - the drive instead of the singlemotor electric drive. In addition, energy losses in the traction asynchronous electric motors included in the single-engine and multi-motor electric drive during acceleration of a full and empty bus to a maximum speed of 12.5 seconds were evaluated. To estimate the losses in the compared electric motors at voltage different from the nominal value, mathematical modeling was used in the MatLab package. It is shown that the use of a multi-motor asynchronous electric drive allows to reduce energy losses in traction asynchronous electric motors when the vehicle is moving at a constant speed and during acceleration with a different number of passengers. Moreover, to obtain the energy effect, the number of engines used in a multi-motor electric
drive should vary depending on the speed and acceleration of the bus, as well as on the total load moment of the multi-motor drive.