What is the ac, dc motors:
Communicate electrical energy and mechanical energy transformation of motor, called ac motor; Can realize dc and mechanical energy of motor, convert each called dc motor.
Ac motor representative: the three-phase level 4 ac motor (asynchronous motor/induction motor) :
Three-phase asynchronous motor as 4 ac motor, of three phase four very refers to the motor of the three phase are 120 degrees of positive and a negative. This kind of motor stator three-phase winding through the three-phase ac into a rotating magnetic field generated, cutting rotor winding, electromagnetic torque. With rotation speed difference is asynchronous motor rotation of the necessary conditions for the name of the asynchronous also from this and come.
The working principle of details I in this temporary not, in the final analysis, we compared to delve into or pay attention to its performance, simple said, asynchronous motors have the following features:
1 simple structure, high reliability, motor itself.
2, easy fabrication, low price.
3, easily into high speed, high voltage, large current capacity, the motor.
4, kinetic energy recovery effect is obvious.
But ac motor technology, while development is rapid, oneself also is a difficult to overcome defects. Asynchronous motor used in electric car to face the biggest problem is starting small torque, the starting current. Asynchronous motor need through the increase starting current to produce large torque, the output power of the battery has certain requirements. Asynchronous motor efficiency is lower, energy feedback performance and high performance is poor. In order to make up for these weaknesses, the use of ac motor electric cars will typically equipped with the gearbox.
Ac or dc?
Although dc motor to start torque advantage by most of the major manufacturers favour, but electric sports car factory tesla business choose the ac motor also shows that ac motor use proper function also don't lose dc motor. What is the future of dc motor take over the world, or ac motor with mature manufacturing process and low prices, now it's hard to say, or take any car companies need according to their own product positioning the choice of appropriate motor.
For consumers actually dc ac motor will not have the too big, important difference between the overall performance of the vehicle and finally, after all, not just a electric motor parts. |