The enhanced productivity and the upgrading of downstream machinery require the adjustable delivery rate of upstream machinery that is the apron feeder. The adjustable delivery rate means increased production capacity. In order to meet the requirements of users， we adopted the methods of speed regulation of the asynchronous motor  according to the specific circumstances of the market at that time.
Methods of speed regulation of the asynchronous motor :from the motor control panel, we can learn that the formula of speed of AC asynchronous motor is N=60*f1/p*(1-s). According to the formula above, the asynchronous motor has the following speed regulation methods.
1 Speed regulating pole change
Pole-changing speed regulation is generally divided into 4/6/8 poles. the number of poles of the motor is in consistent with the speed of the motor, therefore its scope of use is small and it has certain limitations. 2 Slip ratio
This speed regulation method is low efficiency for the slip is too large as well as the large loss of slip at low speed. When we chooses this method, in order to ensure its reliability, the motor with larger motor power is generally selected in light of the calculation of the motor power： for example, if the calculation of the motor power is 45KW, we should use 55KW motor so as to ensures that the apron feeder does not occur insufficient power at low speed. In addition, when this motor is used in metal mines, iron powder is more likely to be absorbed on the carbon brush of the slip ring, which will cause short circuit of the motor working for a long time , resulting in accidents.
3 The frequency control of the asynchronous motor
In order to keep the power factor of the excitation motor basically unchanged, we also expected the track to remain unchanged when regulating the speed frequency of the asynchronous motor .
If the 3 parameters above have changed, there will be a power drop, torque drop, while the motor power can not be fully utilized resulting in waste therefore the track can generally remain the same when frequency control, in order to keep the track constant when frequency changes, the voltage/frequency core diameter is required to be a setting value. The voltage must vary in proportion to the frequency. Apron feeder as a semi-continuous feeding machinery, its working characteristics are low speed and large torque, while its speed regulation form is a typical constant torque speed regulation, which requires a frequency conversion device to ensure that VI varies proportionally with FL. In this way, the motor can be guaranteed to have the same overload capacity in the process of frequency change. When the voltage reaches 10, the output torque is the maximum and constant.
Above we introduced How to Adjust the Speed of Apron Feeder. The HENAN EXCELLENT MACHINERY CO.,LTD is a professional bulk material conveying equipment manufacturer. We have professional production capacity and rich production experience as well as strict product quality inspection . We can guarantee that every equipment we produced is qualified equipment, and we ensure the qualified rate of the products. To know more about our products, Please visit our official website: https://www.exctmach.com/.