Self-starting 50KW three-phase diesel generator price

Most are driven by lower speed turbines or diesel engines. The number of motor poles ranges from 4 poles to 60 poles, and even more. The corresponding rotational speed is 1500 to 100 rpm and below. Due to the low rotational speed, salient-pole rotors that require less material and manufacturing processes are generally used.

Each pole of salient-pole rotor is usually overlapped by 1-2 mm thick steel plate, which is integrated by rivets. Excitation windings are arranged on the pole. The excitation winding is usually made of flat copper wire. The pole shoe of the pole is often equipped with a damping winding. It is a short circuit formed by the bare copper strip in the damping groove of the pole shoe and the copper ring welded at both ends. The pole is fixed on the rotor yoke, which is made of cast steel. Salient pole rotors can be divided into horizontal and vertical types. Most synchronous motors, synchronous cameras and generators driven by internal combustion engines or impulse turbines are of horizontal structure, while low-speed and large capacity hydro generators are of vertical structure.

The rotor of the horizontal synchronous motor is mainly composed of a main magnetic pole, a yoke, a field winding, a collector ring and a rotating shaft. Its stator structure is similar to that of asynchronous motor. The vertical structure must bear the gravity of the rotating part of the unit and the downward pressure of water with the thrust bearing.In the large capacity hydrogenerator, the force can be as high as four or fifty meganewtons (about equal to the gravity of four or five thousand tons of objects), so the structure of the thrust bearing is complex, and the processing technology and installation requirements are very high. According to the location of the thrust bearing, the vertical Hydrogenerator can be divided into two types: suspension type and umbrella type.

The suspension type thrust bearing is placed on the upper or middle part of the upper frame, and it runs stably on the machine when the rotating speed is high and the ratio of rotor diameter to core length is small. The umbrella type thrust bearing is placed on the lower frame under the rotor or on the top cover of the water turbine. The load-bearing frame is a smaller lower frame, which can save a lot of steel and reduce the height of generator and workshop from the base.