Electric Vehicle System Structure
Electric drive
Electric vehicle refers to a vehicle that is powered by on-board power supply and driven by motor to drive wheels, and meets the requirements of road traffic and safety regulations. It uses electricity stored in the battery to start. Sometimes 12 or 24 batteries are used to drive the car, and sometimes more are needed.
The composition of electric vehicle [4] includes: electric drive and control system, mechanical system such as driving force transmission, working device to complete the given task, etc. Electric drive and control system is the core of electric vehicles, and also the biggest difference from internal combustion engine vehicles. The electric drive and control system is composed of drive motor, power supply and speed control device of motor. Other devices of electric vehicles are basically the same as those of internal combustion engines.
Power Supply
It provides electric energy for the drive motor of electric vehicles, and the motor converts the electric energy of the power supply into mechanical energy. The most widely used power source is lead-acid battery, but with the development of electric vehicle technology, lead-acid battery is gradually replaced by other batteries due to its low energy, slow charging speed and short life. The developing power sources mainly include sodium sulfur battery, nickel cadmium battery, lithium battery, fuel cell, etc. The application of these new power sources has opened up a broad front for the development of electric vehicles
Drive motor
The function of the drive motor is to convert the electrical energy of the power supply into mechanical energy, and drive the wheel and working device directly through the transmission device or. However, due to the commutation spark, the DC motor has low power, low efficiency and heavy maintenance workload; With the development of motor control technology, it is bound to be gradually replaced by brushless DC motor (BLDCM), switched reluctance motor (SRM) and AC asynchronous motor, such as shellless disk axial magnetic field DC series motor.