ANALYSIS OF INDEX OF SPECIFIC POWER CONSUMPTION OF THE ELECTRIC VEHICLES
Abstract
The specific consumption rate, which will allow comparing the energy characteristics of the electric vehicles of different masses and different purposes, are analyzed in this paper. the amount of mileage electric vehicles determined Not only by capacity of the independent power supply – battery – but also by driving mode which is determined by driving style. The influence of external factors and driving mode on specific consumption rate are analyzed in this work. Also provides the ways to improve it.
Testing of ecobus on Ducato’s chassis and the need to separate the losses were the starting point of theoretical research
Theoretical substantiation of the main factors of inefficient energy consumption allows to estimate the the contribution of each component of the weight, and the resulting graphs allow to consider the mutual influence of external factors. Physical characteristics of the vehicle, as well as empirical coefficients are taken for electric bus on "Fiat Ducato" chassis.
Since little additional losses while making a turn, the movement has been considered in detail by a straight horizontal section of the road at a constant speed, as well as uniformly accelerated motion during acceleration and braking. The analysis of the curves for these cases at various speeds and accelerations indicates that the growth of the specific consumption rate is associated with increasing rate of acceleration and with an increase in aerodynamic drag (starting from a speed of 20 km / h). In the area of low velocities (up to 10 km / h) decrease in the efficiency of the electric is the determining factor.
Obviously, the most economical mode of motion is motion with constant velocity with the using runs until stop mode. To reduce energy consumption in dynamic modes associated with the change of speed, we can recommend a variety of optimal control laws: minimum heating losses, minimum power consumption or parametric acceleration limiting depending on the speed of electric vehicles.
Further development of the question is seen in the development of recommendations to the driving style and adherence to driving style in order to ensure the efficient use of energy.