Electric car motor electronic control technology, how much do you know
The so-called motor, as its name suggests, is a kind of power component that converts electrical energy and mechanical energy into each other. When electrical energy is converted into mechanical energy, the electric motor exhibits the operating characteristics of the electric motor; when electrical energy is converted into mechanical energy, the electric motor exhibits the operating characteristics of the electric generator. Most electric vehicles in the state of brake braking, mechanical energy will be converted into electrical energy, through the generator to feed back the battery.
The motor is mainly composed of rotor, stator winding, speed sensor, housing, cooling and other components. In the field of new energy vehicles, permanent magnet synchronous motors are widely used. The so-called permanent magnet refers to the addition of permanent magnets when manufacturing the rotor of the motor, so that the performance of the motor is further improved. The so-called synchronization means that the rotational speed of the rotor is always consistent with the current frequency of the stator winding. Therefore, by controlling the input current frequency of the stator winding of the motor, the vehicle speed of the electric vehicle will eventually be controlled. How to adjust the current frequency is the problem to be solved in the electronic control part.
Compared with other types of motors, the biggest advantage of permanent magnet synchronous motors is that they have higher power density and torque density. To put it bluntly, compared with other types of motors, permanent magnet synchronous motors are of the same mass and volume. It can provide maximum power output and acceleration for new energy vehicles. This is also the reason why the permanent magnet synchronous motor is the first choice for the majority of auto manufacturers in the new energy auto industry, which has extremely high requirements on space and self-weight.
In addition to permanent magnet synchronous motors, asynchronous motors have also received extensive attention due to the use of Tesla. Compared to synchronous motors, the rotational speed of the rotor of the motor is always less than the rotational speed of the rotating magnetic field (generated by the stator winding current). Therefore, the rotor appears to be "inconsistent" with the current frequency of the stator winding, which is why it is called an asynchronous motor.
Compared with permanent magnet synchronous motors, asynchronous motors have the advantages of low cost and simple process; of course, the disadvantage is that their power density and torque density are lower than those of permanent magnet synchronous motors.
In addition to synchronous and asynchronous motors, hub motors are also a hot spot for new energy automotive applications. The biggest feature of the hub motor is that the vehicle's power unit, transmission and brakes are integrated into the hub. Compared with the traditional power unit, the advantages of the hub motor are obvious. Due to the large number of transmission components, the vehicle structure is relatively simple. Of course, in the synchronous control of the motor, the wading seal, etc., there are still many problems in the hub motor. solve.
