Design Of Energy Saving Controller For Beam-pumping Units

Beam-Pumping Units is the main equipment and energy consumer in oil-field system. Under the normal operation condition, the average load ratio is small compared to the rated value. So it is of lower efficiency and higher electricity consumption rate. In order to solve such a problem, developing energy conservation equipment of the Beam-Pumping Units is necessary.The thesis puts forward a scheme of reactive-power compensation and the Y-Δvoltage-regulator through introducing the present using the Beam-Pumping Units and external situation of particular working condition.Then the thesis develops a new kind of Y-Δvoltage-regulator and reactive-power compensation controller for energy saving. The ATT7022A is used to detect the power grid operation information to reduce the calculation volume of CPU and enhance the precision of power grid parameter identification. And it also simplifies the design work of software. Atmega128 is utilized as the main process unit and the method of combining power factor control and voltage limitation is used as the system working mode. Specific voltage phase is determined to switching shunt capacitor by thyristors controlled by MOC3083. Thus the surge produced during the traditional capacitor switching method is greatly diminished. Switching strategy is applied to alleviate the resonance via multi-measurement average and specifying switching interval during consecutive capacitor switching. The device can record significant data, such as system operation condition and power grid information, for 150 days at most. It provides diverse protect measures to ensure the stability and reliability. It bears friendly human machine interface and communication interface which is convenient for use. In the part of software, the controller adopts hierarchical structure and decreases the interfere of each parts. It increases the broadening function of program.The parts of hardware and software are completely finished. And the equipment can control the capacitors accurately through the test and fully meets the demand of energy saving and reactive power compensation.