The Design And Research Of The Intelligent Hybrid AC Contactor

AC contactor is a kind of Electrical Apparatus which is widely used. The capability of the AC contactor not only affects the benefit of the industry producer, but also affects electricity quality and electric power resource. Benefited from the application of the new material, the mechanical life of AC contactor is up to 15 000 000 operations. However, its electrical life is only 10% of its mechanical life. Specially, while AC contactor is used at utilization category AC-4, the contacts erosion mostly occurs in the process of pick up. Thus, it demands that AC contactor can be controlled optimally in order to decrease contacts bumping, pick up and reset without arc and reduce arc erosion. While the electric power resource is declining, it needs AC contactor running in energy-saving way. Combined with the above demands, intelligence and zero arc technique for AC contactor was researched here.This paper researched the principle of the rebound of contacts, contrasted the AC excitation way and the DC excitation way, then brought forward the scarcity of AC excitation mode and the advantage of the other way. Under a great deal of test, the optimal excitation voltage for DC excitation was determined. Combined with the shortage of the control mode for DC excitation in existence, the excitation control mode that is multi-segment pulse excitation with steady voltage was proposed. In order to improve the control precision, MOSFET was applied in the switch-on-off operation circuit. The DC power designed here ensured that the excitation power could keep steadily when the voltage of electrical network fluctuated 20%. All the designation realized CJ20-25 AC contactor less-first and non-second rebound that would improve the electrical life. By contrasting the AC holding and DC holding way, the operating mode with lower DC holding voltage was proposed. It realized saving energy, zero noise and switch-off controlled. By analyzing the characteristics of triphase voltage and current as the load was disconnected, the function parameters of TRIAC were calculated. Based on the analysis of various trigger modes, the suitable current phase trigger method was put forward. Adopting TRIAC and driven circuit built the electronic extinguishing arc module. Combined with the intelligence...