source of technology
Introduced, digested and absorbed the advanced and mature design and manufacturing technology of electric wheel drive motors and traction generators from abroad. The motors for the 130-ton, 170-ton and 220-ton series dump trucks of Belas, and the motors of the GE 150-ton and 240-ton drive systems, which were originally completely dependent on imports, have been domestically modified, all of which have been successful. On this basis, this technology is applied to the design and manufacture of independent motor products to produce motor products that meet the requirements of domestic OEMS.
The electric wheel dump truck is driven by an electric drive, which is driven by a diesel engine to drive a synchronous traction generator, which generates alternating current. The alternating current passes through the control cabinet to drive the traction motors installed on the left and right sides of the rear axle. The motor outputs mechanical torque, which is transmitted to the wheel hub through the wheel-side reducer to drive the vehicle.
At present, the mainstream AC synchronous generators for mining vehicles have two technical solutions: harmonic excitation and brushless excitation.
Harmonic excitation is to add a set of independent third-harmonic auxiliary windings to the generator stator slots, and the harmonic AC voltage is drawn from the stator, rectified by the static converter, and then sent to the generator rotor excitation winding through slip rings and brushes , The program of excitation. This scheme has the characteristics of simple structure, fast response speed and high reliability.
Brushless excitation is to add AC excitation generator and rectifier device inside the original generator. The stator poles of the excitation generator introduce controllable DC excitation electricity from the excitation control cabinet to make the armature of the excitation generator generate three-phase alternating current. After being rectified by the rectifying module that rotates with the shaft, it is sent to the excitation coil of the main generator rotor. Such a scheme can greatly extend the maintenance cycle of the motor.
The driving motor is the power source of the vehicle. The driving speed of the vehicle is directly proportional to the speed of the motor. The highest parameter of the vehicle depends on the highest speed of the motor, and the climbing ability of the vehicle directly depends on the maximum torque of the motor.
The drive motor adopting AC asynchronous frequency conversion speed regulation transmission has the following characteristics:
1).The motor can realize stepless speed regulation;
2).The starting current is small, reducing the capacity of the power supply equipment;
3).Smooth start, can eliminate mechanical impact;
4).With protection function. It can reduce the maintenance cost of the motor;
5).Has a significant power saving effect;