The Research Of Submersible Motor Reactive Power Compensation Control System Based On LabVIEW

Electrical equipments are common in the petroleum enterprises, submersible motor is widely used as special oil production equipment in this field. Submersible motor consumes a large amount of reactive power, large amount of reactive power not only has serious influence on the quality of electric energy, but also has adverse effects on the quality of the grid, the security of equipment and economic benefits. Virtual instrument technology is developing rapidly in the engineering test in recent years, therefore, utilizing virtual instrument technology to control automatic reactive power compensation of submersible motor has a good practicality. Traditional reactive power compensation equipment cannot dynamically and quickly meet requirements of variable load reactive power compensation. SVG is a new kind of reactive power compensation equipment, which is superior in compensation of variable load reactive power. This technology has become the research hotspot, domestic and foreign scholars focus on it, so we conduct a research on developing and optimizing a reactive power compensation control system suitable for compensating submersible motor,which has a profound significance on improving efficiency of electricity and energy savings.This article describes the development of reactive power compensation device, analyses the principle of reactive power generator considering the basic structure and operation characteristics of submersible motor. On the basis of mastering instantaneous reactive current detection method based on d-q coordinate transformation, we research a new instantaneous reactive current extraction method named PLL replace. Compared to the reactive current detection method in the three-phase voltage asymmetry system, the detection principle structure of the new method is simple and flexible, the new method has a small amount of computation, can effectively reduce error, and it can also be directly applied in symmetrical or asymmetrical three-phase voltage systems. After analyzing the control strategy of reactive power generator, this paper presents a current direct control method of positive and negative sequence reactive current synchronous compensator based on d-q coordinate transformation for asymmetric system. The two controllers work at the same time to accomplish positive and negative sequence reactive component compensation. Furthermore, we design a hardware circuit for automatic reactive power compensation control system of submersible motor based on LabVIEW. Combining LabVIEW software programming, soft start of submersible motor,acquisition and display of related operating parameters of motor, development of control algorithm of SVG automatic reactive power compensation, query and storage of historicaldata, generation of report and fault tips can all be implemented through this system. The results show that automatic reactive power compensation control system of submersible motor we designed in this article can achieve dynamic reactive power compensation, can effectively suppress current imbalance of system. The reliability of optimized control algorithm and rationality of system operation is evidenced by experimental analysis.Automatic reactive power compensation control system of submersible motor has good theoretical and practical value.