Simulation And Experimental Research On Dynamic Characteristics Of Intelligent AC Contactor

AC contactors are a type of low-voltage apparatus operating frequently.Abrasion and arcs, which are caused by contacts’ bouncing and iron cores’collision when a contactor is charged, reduce the property and life span of thecontactor greatly. Therefore，the research on contactors’ dynamic characteristicsis of important significance. The paper takes a CJ40-500series AC contactorwith an intelligent module as the main research object. Simulation and analysisof its dynamic characteristics are executed in closing processes. The majorcontents are as follows:First of all, a3D model of the intelligent AC contactor is established bySolidWorks. The model can be imported into COMSOL, ADAMS or MTLABby special interfaces module to simulate the contactor’s dynamic characteristics.Thus, it can decrease a large amount of extra workload caused by repetitivemodeling.Secondly, a mathematical model for the electromagnetic operatingmechanism of the AC contactor is analyzed from magnetic field, circuit andmechanical equations. In the analysis of magnetic field equations,3D staticcharacteristics of the electromagnetic operating mechanism is computationallyanalyzed by COMSOL based on a finite element method, thus flux linkage andelectromagnetic force in different air gaps and different currents can becalculated. Hence the table of the relationship between electromagnetic force,flux linkage, current and air gaps in a static condition can be obtained. Thirdly, the3D model of contactor established by SolidWorks is importedinto ADAMS. Then, we install the mechanical model by adding motions to theprevious model, and configure the input variables and output variables.Fourthly, the mechanical model is imported into MATLAB, and a controlsystem is set up in MATLAB. Then, an ADAMS-MATLAB co-simulation forthe intelligent AC contactor in closing processes is realized. Dynamiccharacteristics of the contacts and the armature in different experimentalconditions can be calculated by the simulation system.Fifthly, a dynamic characteristics test-system is built for the intelligent ACcontactor based on LabVIEW. The test-system which can acquire signalsaccurately and synchronously, describes the real-time dynamic characteristics ofthe intelligent AC contactor. Thus the simulation system can be improved bycomparing the results acquired by the test-system and simulated by thesimulation system.Finally, the dynamic characteristics of the intelligent AC contactor aresimulated by the simulation platform. The platform simulates and analyzes thecollisions, bounces and velocities of the contacts and the armature, in differentparameters of the main springs; the differences of the dynamic characteristicsbetween a collision contactor and a non-collision contactor in closing processesare compared; the influences of different armature masses in closing processesare calculated and analyzed.In this paper, simulation results coincide well with experimental results bycomparing simulation data and test data. It proves the simulation system canpredict the dynamic characteristics of contactors precisely. Thus the research inthis paper has a guiding value in the study of the dynamic characteristics andthe optimal design of contactors.