Power-saving Technology of the Oil Pumping Unit

The working principle of the oil pumping unit is actually the same as the principle of pumping water from our own wells at home, that is, the oil is pumped up by a piston rod (sucker rod) and then sent away through the underground pipeline. The only difference is that the action of the pulling rod is driven by a motor.

There are many forms of oil pumping units. The most common one that can be seen on TV is the oil pumping unit with a large fan-shaped iron block. It moves back and forth, so it is also called the "kowtow machine." The shape design of the oil pumping unit is not for energy saving, but for reducing the impact on the power grid. This is because when the sucker rod falls, the motor does not work. On the contrary, there is electric energy feedback to the power grid. There are many oil pumping units in oil fields. These feedback electric energy cause serious distortion of the power grid. Therefore, some oil pumping units have multiple treatment methods such as feedback braking or feedback inversion.

The power-saving technology of the oil pumping unit adopts variable frequency speed control, which can change the long-term low-efficiency work status of the oil pumping unit, making its working mode match the actual load of the oil well, and ensure that pumping is conducted every time, reducing inefficient or even invalid pumping, thereby reducing electricity expenses, reducing maintenance costs, and improving operating efficiency. Its effects are as follows:

1) The inverter has a soft starter function. The current is weak when starting, so it has a small impact on the power grid and the energy consumption during starting is greatly reduced. It avoids the equivalent of 3 to 7 times the rated current when starting, and avoids unnecessary power loss. At the same time, the impact on the oil pumping unit is reduced and the service life of the equipment is prolonged. During work, the power factor of the motor can be increased from 0.2 ~ 0.5 to 0.9, which reduces the burden on the power grid and transformers, reduces line losses, and greatly reduces reactive power losses.

2) The introduction of frequency converter control can realize the automatic identification of the up and down strokes of the equipment, so that the operating frequency of the up and down strokes of the oil pumping unit can be adjusted respectively, in order to change the operating speed of the up and down strokes of the oil pumping unit. It solves the production stoppage caused by changing the pulley speed, thereby improving the efficiency in production. At the same time, it meets the requirements of consuming the least power under the condition of achieving the pump efficiency.

3) Since the load is geopotential when the oil pumping unit is going down, the inverter can adapt to its working conditions after installing the dynamic braking function. It is very convenient for changing the speed of the oil pumping unit to adjust the best working state. It can also reduce leakage and improve pump efficiency.