A composite
energy storage system based on a stepless speed
change type flywheel and a
power battery is characterized in that the composite
energy storage system can be controlled to operate in different working
modes according to different automobile operation working conditions, and the requirements of an automobile for
high power density,
high energy density,
high energy conversion efficiency and long service life of the
energy storage system can be met at the same time. Under the starting condition of the vehicle, the
discharge current of the
power battery can be reduced and the service life of the
power battery system can be prolonged by virtue of the high-
power density advantage of the stepless speed
change type flywheel; under medium-high driving demand power, the composite energy storage system works in a dual-
energy supply mode, and by means of the
advantage of
high power density based on the stepless speed
change type flywheel, the
power demand of the whole vehicle can be met, large-current
discharge of a power battery can be prevented, the service life of the power battery is prolonged, and the working efficiency of the system is improved; under low driving demand power,based on the fact that the stepless speed change type flywheel does not participate in whole
vehicle driving, the whole vehicle controller controls the
electric energy output by the power battery tobe converted into
mechanical energy through the motor at the same time, and then part of the remaining
mechanical energy obtained after whole
vehicle driving is met is transmitted to the flywheel so as to control the stepless speed change type flywheel to operate in an efficient state; and under the emergency braking working condition, by means of the
advantage of instantaneous high-power feedbackbased on the stepless speed change type flywheel, more braking energy can be fed back compared with a conventional single-power-
battery energy storage system, the energy utilization efficiency of thewhole vehicle is improved, large-current charging of a power battery can be prevented, and the service life of the power battery is prolonged.