Beam pumping unit is the conventional pumping equipment that used widely in oil field, it is  dragged directly by common AC asynchronous motor. Its crank with balance weight bring along sucker rod of oil wells to drive subsurface pump in the well to move up and down periodically, so it carry the oil in the well to the ground. In one frequency-stroke, with the rise/fall of sucker rod of oil wells, the motor is in the state of electric motion/ electricity generation. During rise, motor absorb energy from elec. net to electric run; during descending, the load character of motor is potential load, the motor is in the state of electricity generation.

 However, the oil circs down the well is very complex, it has rich and poor oil well difference, rare and dense oil well difference.  The invariable-speed application problem is obvious. for the pumping unit, the piston after abrasion and the interval leakage of bush are the difficult problem, besides, the variable stratum factor such as there are sand, wax, water, gas etc. in the oil also have influence for the oil quantity that every time pumping. So it can arrive the best control by speed regulation drive. 

After introducing into speed regulation drive, to modulate stroke frequency time of pumping unit according to the state of well and modulate the speed of up, down operation, at the same time of improving full of modulus of pump, reduce the leakage of pump, for getting maximum oil quantity.  especially the color frequency variation and speed regulation has no start stroke, it can also solve the problem of pumping unit power surplus 、 loading rate is too low 、 power factor is too low, so this can increase efficiency and improve the lifetime of whole machine.

Among the many projects of speed regulation drive, the common is the product of interval work power saving, voltage regulation and speed regulation power saving  and inverter speed regulation power saving.

The product of interval work power saving is aim at the detailed situation of small output and even empty pumping for poor oil well and old oil well etc., for the oil well that less than economic volume, adopt simple Y/△ transform auto start and stop by micro-process technology with transducer, this can ensure the maximum efficiency when pumping unit start the machine, and this can save energy.

The product of voltage regulation power saving modulate motor voltage according to pumping unit charge variation, it makes the work power of pumping unit match with actual charge, so this arrive to save energy aim.

Energy saving effect of above product is less than frequency control machine, so adopting  frequency variation and speed regulation to rebuild oil extraction is imperative under the situation.