Study Of Intelligent Phase Control Technology And Device Base On AC Contactor

The AC contactors which was used to switching capacitor were applied massively in the Var Compensation domain, it has the advantages that simple control and no voltage drop during the time of switch-on which the SCR do not have. But the overvoltage and inrush current always happen under the traditional control methods, that would be terrible effect on the life of capacitors and contactors. The synchronic phase control technology may solve that problem effectively, it request that zero current break and zero voltage close, no bounce in the process of closing, no arc in the process of opening and saving-energy when the contactor was closed. Synthesized the above demands, the paper chose CJX1-12AC contactor as research object, and AC contactor intelligent synchronic phase control technology in three aspects-theoretical modeling, simulation analysis and experimental investigation-was researched.First, the excellence of DC voltage excitation was analyzed, static and dynamic model of AC contactor which was under DC voltage excitation were built with magnetic circuit method, on that base, the whole process of closing was simulated using the MATLAB language. Variation trend of the core was analyzed through the Simulation curves, and introduced a method of sectional excitation which could reduce terminal velocity of the core effectively and enhance performance index in the process of closing.Secondly, the intelligent synchronic phase control device experiment platform was built, the feasibility of the sectional excitation were validated through the test of close, further more the test showed that sectional excitation reduced the core strike and cleared up contactor bounce effectively. Base on discussed the properties of arc break, arc duration and arc current in the different condition of breaking phase were measured. Arcing energy was calculated in different breaking phase, and optimal breaking phase was chose base on the curve of arcing energy.Last but not the least, develop the AC contactor based on a brand-new controlling method, intelligent synchronic phase control device experiment was made. The experiment results indicated that intelligent synchronic phase control technology has realized dynamic control in the process of closing and zero current break, the overvoltage and inrush current were solved effectively, no voltage drop during the time of switch-on, conduction loss reduced, the contactor erosion was decreased, the paper provide a theoretical and experimental foundation for improve electrical life of AC contactor.