Novel tri-power, efficient, energy-saving three-phase asynchronous motor used for oil extractor

Abstract

The invention discloses a novel tri-power, efficient, energy-saving three-phase asynchronous motor used for an oil extractor, which comprises a rotor and a stator winding; the stator winding adopts the unique 3Y composite series connection method and the novel technology of turn removal; the stator winding corresponds to a low power grade, a medium power grade and a high power grade, and the number of turns of serial coils in each phase reduces with the power grade, with the low grade power corresponding to a maximum number of turns and the high grade power corresponding to a minimum number of turns; and the switch among the three power grades is achieved by three contactors. As the invention has the high, the medium and the low power grades which are all available for option, and the high power grade has a high start-up torque and is applied to starting the oil extractor, the motor can automatically operate at the low or medium power grade on the completion of the start-up process, and can realize two-way automatic switch of operating power according to the change in the working condition of an oil well. As the motor has the advantages of great start-up torque, high operating efficiency and power factor, convenient control, good reliability and remarkably reduced no load current, the motor can achieve better energy-saving effect.

Description

technical field [0001] The invention belongs to the technical field of motors, in particular to a novel three-power, high-efficiency and energy-saving three-phase asynchronous motor for a pumping unit. Background technique [0002] The beam pumping unit is the most widely used mechanical device in oil exploitation in my country. The load characteristic of its dragging motor requires a large starting torque, but the actual operating load torque is not large. In order to adapt to such a load, the starting torque is generally required to be more than 3 to 4 times the actual load torque when selecting a motor. In addition, the load of the motor of the pumping unit fluctuates periodically. When it is lifted, the motor is loaded and absorbs power from the grid. When it is down, the motor is lightly loaded, and may even work in the state of power generation, sending electric energy to the grid. This has caused two problems in practice: one is that the actual load rate of the moto...

AI Technical Summary

Problems solved by technology

This has caused two problems in practice: one is that the actual load rate of the motor is small, the efficiency and power factor decrease, and a serious waste of electric energy is caused; the other is that the operating load fluctuation causes the system loss to increase

The Y-Δ connection conversion winding is relatively advanced, but it only has two power levels, and the switching is complicated. The power ratio of these two levels is limited to a fixed value. , cannot be adjusted, of course, there is no guarantee that the motor will run in the best working condition

Generally speaking, these technical solutions have little improvement in performance, high cost, complex control conversion, and poor reliability, which cannot really meet the needs of my country's oilfields, and are actually difficult to popularize and apply.

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