Power supply
The power supply provides electrical energy for the driving motor of the electric motorcycle, and the motor converts the electrical energy of the power supply into mechanical energy, and drives the wheels and working devices through the transmission device or directly. Today, the most widely used power source for electric vehicles is lead-acid batteries, but with the development of electric vehicle technology, lead-acid batteries are gradually replaced by other batteries due to their low specific energy, slow charging speed, and short lifespan. The application of new power sources is being developed, opening up broad prospects for the development of electric vehicles.
Drive motor
The function of the drive motor is to convert the electrical energy of the power source into mechanical energy, and drive the wheels and working devices through the transmission or directly. DC series motors are widely used in today's electric vehicles, which have "soft" mechanical characteristics, which are very consistent with the driving characteristics of automobiles. However, due to the existence of commutation sparks, DC motors have low specific power, low efficiency, and heavy maintenance workload. With the development of motor technology and motor control technology, it is bound to be gradually replaced by brushless DC motors (BCDMs) and switched reluctance motors. (SRM) and AC asynchronous motors replaced.
Motor speed control device
The motor speed control device is set for the speed change and direction change of the electric vehicle, and its function is to control the voltage or current of the motor, and complete the control of the driving torque and rotation direction of the motor.
In the previous electric vehicles, the speed regulation of the DC motor was realized by connecting a resistor in series or changing the number of turns of the motor's magnetic field coil. Because the speed regulation is step-by-step, it will generate additional energy consumption or the structure of the motor is complicated, and it is rarely used today. Thyristor chopper speed regulation is widely used in electric vehicles today, and the stepless speed regulation of the motor is realized by uniformly changing the terminal voltage of the motor and controlling the current of the motor. In the continuous development of electronic power technology, it is also gradually replaced by other power transistors (GTO, MOSFET, BTR and IGBT, etc.) chopper speed control devices. From the perspective of technological development, with the application of new drive motors, it will become an inevitable trend to transform the speed control of electric vehicles into the application of DC inverter technology.
In the rotation conversion control of the driving motor, the DC motor relies on the contactor to change the current direction of the armature or the magnetic field to realize the rotation conversion of the motor, which makes the Confucius circuit complex and reduces the reliability. When the AC asynchronous motor is used for driving, the change of the motor direction only needs to transform the phase sequence of the three-phase current of the magnetic field, which can simplify the control circuit. In addition, the use of an AC motor and its variable frequency speed control technology makes the braking energy recovery control of the electric vehicle more convenient and the control circuit simpler.
Travel device
The function of the traveling device is to turn the driving torque of the motor into a force on the ground through the wheels, and drive the wheels to walk. It has the same composition as other cars, consisting of wheels, tires and suspension.
Braking device
The braking device of an electric vehicle, like other vehicles, is set up for the vehicle to decelerate or stop, and usually consists of a brake and its control device. In electric vehicles, there is generally an electromagnetic braking device, which can use the control circuit of the driving motor to realize the power generation operation of the motor, so that the energy during deceleration and braking can be converted into the current that charges the battery, so as to obtain regeneration.
Working equipment
The working device is specially set up by the industrial electric vehicle to complete the operation requirements, such as the lifting device, the gantry, and the fork of the electric forklift. The lifting of the fork and the tilting of the mast are usually done by a hydraulic system driven by an electric motor.
