As a very common means of transportation, electric two-wheeled vehicles are widely used in every corner of the city. Electric two-wheeled vehicle, also called electric bicycle, is a kind of vehicle with battery as auxiliary energy source, which is more environmentally friendly and energy-saving than traditional motorcycle. Electric two-wheeled vehicles have been widely used in urban travel, express delivery, take-away and other fields, with the advantages of convenience, economy and environmental protection.

Composition and working principle of electric two-wheeled vehicle

The main components of electric two-wheeled vehicle include frame, motor, battery, controller, transmission system, sensor and so on. The motor is the power source of the electric two-wheeled vehicle, which drives the motor to run through the electric energy provided by the battery, thus pushing the vehicle forward. The controller is responsible for controlling the speed and direction of the motor to ensure the stable operation of the vehicle.

The working principle of the main electric two-wheeled vehicle in the market is as follows: its drive and control system is mainly composed of battery pack, motor, controller and speed control handle. The current in the battery pack is modulated and demodulated by the speed control handle and controller to supply power to the motor, so as to control the motor speed to drive the vehicle to run. The current of the battery pack is supplied to the controller, and the step-down device in the controller supplies power to the speed-regulating handle. Rotating the speed-regulating handle can make the controller detect different voltage values, and the controller can simulate and adjust the voltage delivered to the motor according to the voltage values, thus controlling the speed of the motor and the running speed of the electric vehicle.

Usually, there are several kinds of BMS architectures for electric two-wheeled vehicles, some of which are different in that the charging and discharging MOS is placed on the high side or the low side, and some are different in that the charging and discharging are connected in series or in parallel. At present, many BMSs of two-wheeled vehicles on the market use bottom-side series architecture, and the driving circuit is relatively simple.

At present, the mainstream BMS architecture of electric two-wheeled vehicles in the market consists of main control, battery, secondary protection and analog front end. This is double protection by using AFE to control the ON/OFF of MOS tube and secondary protection chip to control the three-terminal FUSE. Here is the BMS structure diagram.

The electric drive system is a highly integrated and intelligent system, which converts the electric energy in the battery into mechanical energy to drive the vehicle forward, and optimizes the performance and safety of the vehicle through various sensors and control systems. Usually, the traditional H6 bridge is used in the electric drive of most electric two-wheeled vehicles in the market, and the FOC control mode is the mainstream, which has the characteristics of small torque fluctuation, high efficiency, low noise and fast dynamic response.

The single rotation of the motor is larger than 2000A, which requires higher EAS of MOS. For 48/60V batteries, 85V withstand voltage MOS is usually selected, and for 60/72V batteries, 100V withstand voltage MOS is usually selected.

NMOS products of Hottech

As a manufacturer specializing in discrete devices, Hottech has many products applied to electric two-wheeled vehicles. The following products are arranged by Hottech's product manager. Welcome to buy them.

As a convenient, economical and environmentally friendly means of transportation, the quality of electric two-wheeled vehicle is very important. As an indispensable main discrete device product in the vehicle, the quality of MOS product is directly related to the use experience and safety of the vehicle, so it is very important to choose a good supplier. When purchasing MOS products, everyone should pay attention to the car application scene, product performance and company brand, choose the product that suits them best, and avoid stepping on the pit to make themselves suffer losses.