Power supply
The power supply provides electric energy for the driving motor of the electric motorcycle, and the electric motor converts the electric 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. However, 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 life. 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 supply 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. This kind of motor has “soft” mechanical characteristics, which is very consistent with the driving characteristics of automobiles. However, due to the existence of commutation sparks in DC motors, the specific power is small, the efficiency is low, and the maintenance workload is large. With the development of motor technology and motor control technology, it is bound to be gradually replaced by brushless DC motors (BCDM) and switched reluctance motors. (SRM) and AC asynchronous motors.
Motor speed control device
The motor speed control device is set up for the speed change and direction change of the electric vehicle. 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 resistors in series or changing the number of turns of the motor magnetic field coil. Because its speed regulation is step-level, and it will generate additional energy consumption or use a complex structure of the motor, it is rarely used today. Thyristor chopper speed regulation is widely used in today’s electric vehicles. By uniformly changing the terminal voltage of the motor and controlling the current of the motor, the stepless speed regulation of the motor is realized. In the continuous development of electronic power technology, it is gradually replaced by other power transistors (into GTO, MOSFET, BTR and IGBT, etc.) chopper speed control device. From the perspective of technological development, with the application of new drive motors, it will become an inevitable trend that the speed control of electric vehicles will be transformed into the application of DC inverter technology.
In the rotation direction conversion control of the drive motor, the DC motor relies on the contactor to change the current direction of the armature or the magnetic field to realize the rotation direction conversion of the motor, which makes the Confucius Ha circuit complex and reduces reliability. When the AC asynchronous motor is used to drive, the change of the motor steering only needs to change the phase sequence of the three-phase current of the magnetic field, which can simplify the control circuit. In addition, the AC motor and its frequency conversion speed regulation control technology make the braking energy recovery control of the electric vehicle more convenient and the control circuit simpler.
Traveling 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 to drive the wheels to walk. It has the same composition as other cars, consisting of wheels, tires and suspensions.
Braking device
The braking device of an electric vehicle is the same as other vehicles, it is set for the vehicle to decelerate or stop, and usually consists of a brake and its operating device. On electric vehicles, there is generally an electromagnetic brake device, which can use the control circuit of the drive motor to realize the power generation operation of the motor, so that the energy during deceleration and braking can be converted into the current for charging the battery, so as to be recycled.
Working equipment
The working device is specially set up for industrial electric vehicles to complete the operation requirements, such as the lifting device, mast, and 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.
National standard
“Safety Requirements for Electric Motorcycles and Electric Mopeds” mainly specifies the electrical appliances, mechanical safety, signs and warnings, and test methods of electric motorcycles and electric mopeds. These include: the heat generated by electrical appliances should not cause combustion, material deterioration or burns; power batteries and power circuit systems should be equipped with protection devices; electric motorcycles should be started by a key switch, etc.
Electric two-wheeled motorcycles: driven by electricity; two-wheeled motorcycles with a maximum design speed greater than 50km/h.
Electric three-wheeled motorcycle: a three-wheeled motorcycle driven by electricity, with a maximum design speed of more than 50km/h and a curb weight of not more than 400kg.
Electric two-wheeled mopeds: two-wheeled motorcycles driven by electricity and meeting one of the following conditions: the maximum design speed is greater than 20km/h and not greater than 50km/h; the curb weight of the vehicle is greater than 40kg and the maximum design speed is not greater than 50km /h.
Electric three-wheeled mopeds: driven by electricity, the maximum design speed is not more than 50km/h and the curb weight of the whole vehicle is not more than
400kg three-wheeled moped.
Post time: Jan-03-2023