Electric vehicle motor principle
A small partner who is not particularly familiar with the motor, the first level of contact with the motor is fainted by the complex and cross-class of the motor. This article deals with the basic working principle of each type of motor for the types of motors commonly used in electric vehicles. You will find that although there are many classifications, there are not many basic structures. Finally, in the form of a table, the key features of the motor can be seen at a glance.
Try to erase the complex features of the surface, starting with the basic structure and understanding the working principle of electric motor motors.
DC
The choice of electric car is generally DC brushless motor, but the principle is from the brush DC, the brush DC is clear, no brush will understand.
Brushed DC motor working principle
Brushed DC motor
As shown in the figure, a brushed DC motor consists of a main magnetic pole, a winding coil, a photo changer and a brush.
The rotor coil is DC-connected and placed in a magnetic field in a fixed direction. According to the left-hand rule, the electromagnetic forces received by the upper and lower edges of the coil are opposite in direction, forming a torque that causes the coil to rotate.
When the coil is rotated through 90 degrees, if the current is still in the original direction, the coil will be subjected to the torque opposite to the original motion direction, and the motion stops and starts the reverse motion. The coil will plung into a continuous swing state.
At this time, add brushes and commutators between the coil and the power supply. When the coil turns 90 degrees, the direction of motion is parallel to the direction of the magnetic field line, and the vicinity of the point where the positive and negative moments are balanced, the brush is separated from the original commutator piece and is in contact with another commutator piece, that is, the direction of the current flowing through the coil is reversed.
Due to the inertia, the coil rushes past the moment balance position. At this moment, the current direction in the coil also changes. The coil is forced at this time, just in the same direction as the motion, and then the state continues to move.
