If the components of the electric scooter are separated and evaluated one by one, the cost of the motor and control system is the highest. At the same time, they are also the “brain” of the electric scooter. The start, operation, advance and retreat, speed and stop of the electric scooter depend on the motor control system in the scooter.
The electric scooter can run quickly and safely. It has high requirements for the performance of the motor control system and the efficiency of the motor. At the same time, as a practical vehicle, the motor control system is required to withstand vibration, harsh environment and high reliability.
The hardware design scheme of conventional scooter control system is shown in the figure below, mainly including driveMCU, gate drive circuit, MOS drive circuit, motor, Hall sensor, current sensor, speed sensor and other modules.
MCU works through power supply and communicates with the power supply and power module through communication interface and charging module. The door drive module is electrically connected with the main control MCU and drives the BLDC motor through the optimostm drive circuit. Hall position sensor can sense the current position of the motor, and current sensor and speed sensor can form a double closed-loop control system to control the motor.
After the motor is started and operated, the hall sensor senses the current position of the motor, converts the position signal of the rotor magnetic pole into an electrical signal, provides correct commutation information for the electronic commutation circuit, controls the switching state of the power switch tube in the electronic commutation circuit, and feeds back the data to MCUsinglechip。
The current sensor and speed sensor form a double closed-loop system. When the speed difference is input, the speed controller will output the corresponding current. Then the difference between the current and the actual current is used as the input of the current controller, and then the corresponding PWM is output to drive the permanent magnet rotor to rotate continuously for commutation control and speed regulation control. The use of double closed-loop system can enhance the anti-interference of the system. The double closed-loop system increases the feedback control of current, which can reduce the overshoot and supersaturation of current and obtain better control effect. It is the key to the smooth movement of electric scooter.
Some scooters are also equipped with an electronic anti lock system. The system detects the wheel speed by sensing the wheel speed sensor. If the wheel is locked, the braking force of the locked wheel is automatically controlled to make it in the state of rolling and sliding (the side slip rate is about 20%), so as to ensure the safety of the owner of the electric scooter. Device chip is committed to providing customers with competitive products. It is a professional provider of storage solutions.