Aluminum Alloy CNC Machining Services Motor Housing For Electric Drive

Different Types of Electric Drive Motor Housing

1.DC motor
*The main advantage of brush DC motor is simple control and mature technology. They have excellent control characteristics that are incomparable to AC motors.It can be manufactured by CNC engraving, Sand Casting, transparent acrylic(PMMA/PC) 3D Printing.
* Due to the existence of brushes and mechanical commutator, not only limit the motor overload capacity not speed further increase, and if long time operation, it is inevitable to often maintain and replace the brushes and commutator.
* Due to the presence of losses on the rotor, making it difficult to dissipate heat, limiting the further improvement of the motor torque to mass ratio. In view of the above defects of DC motor, DC motor is not used in new electric vehicles.

2.AC three-phase induction motor
*AC three-phase induction motor is the most widely used motor. Its stator and rotor are laminated with silicon steel sheet and there is no mutual contact between stator and slip ring, commutator and other parts. It is simple in structure, reliable in operation and durable.
*The power of AC induction motor covers a wide range of speed from 12,000 to 15,000 r/min. It can be cooled by air or liquid one way or the other, and the cooling freedom is high.
*The AC induction motor has good adaptability to the environment and is capable of regenerative feedback braking. Compared with DC motor of the same power, it has higher efficiency, about half of the mass, cheaper and easier maintenance.

3. Permanent magnet brushless DC motor
*The permanent magnet brushless DC motor is a kind of high performance motor. The brushless DC motor with DC motor characteristics has a rectangular waveform of counter-electromotive force and supply current, so it is also called a rectangular waveform synchronous motor.
*It uses permanent magnet rotor, no excitation loss: the heat generating armature winding is mounted on the stator outside again, so heat dissipation is easy, therefore, the permanent magnet brushless DC motor has no commutation spark, no radio interference, long life, reliable operation and easy maintenance. *Its speed is not limited by mechanical commutation, and it can run at up to several hundred thousand revolutions per minute if air bearings or magnetic levitation bearings are used. Compared with permanent magnet brushless DC motor system, it has higher energy density and higher efficiency, and has good application prospect in electric vehicles.
* The working principle of permanent magnet brushless DC motor is to use the motor rotor position sensor output signal to control the electronic commutation line to drive the power switching device of the inverter, which energizes the armature windings in turn, thus generating a jumping rotating magnetic field on the stator and dragging the motor rotor to rotate. At the same time, as the motor rotor rotates, the rotor position sensor continuously sends position signals to change the energized state of the armature winding, so that the current in the conductor at a certain pole remains unchanged one way or the other, and the motor rotates.

4. Permanent magnet synchronous motor is actually a kind of convex pole motor, which generally adopts the three-phase symmetrical winding similar to that of three-phase AC motor in the stator structure, and the AC power supply is modulated into three-phase sinusoidal voltage with variable voltage through AC-DC voltage inverter or DC-DC voltage inverter. The AC power supply is modulated into three-phase sine wave voltage with variable voltage through AC-DC voltage inverter or DC-DC voltage inverter, which is fed into the three-phase symmetrical winding of the permanent magnet synchronous motor to produce three-phase symmetrical currents.

5. Switching reluctance motor
*The switched reluctance motor is a new type of motor, the system has many obvious features: its structure is simpler than any other motor, there is no slip ring, winding and permanent magnet on the rotor of the motor, but only a simple centralized winding on the stator, the end of the winding is short, there is no inter-phase jumper, easy to maintain and repair.
*Switching reluctance motor has highly nonlinear characteristics, therefore, its drive system is more complicated. Its control system includes a power converter. However, the research in recent years shows that the noise of switched reluctance motor can be completely well suppressed by adopting reasonable design, manufacturing and control technology.

6. The performance of various drive motors used in electric vehicles is compared.

At present, the cost of AC motor, permanent magnet motor and switched reluctance motor, as well as their control devices, is still relatively high. After forming mass production, the price of these motors and unit control devices will be rapidly reduced, which will be able to meet the requirements of economic efficiency and make the price of the whole electric vehicle lower.