How　to　improve　the　electrical　energy　utilization　of　traditional　mechanical　and　electrical　equipment　is　a　problem　that　deserves　to　be　discussed,　especially　now　when　energy　usage　and　sustainability　is　becoming　more　and　more　important.　From　the　view　point　of　energy,　the　closing　process　of　AC　contactor　is　an　energy　exchange　process　with　the　input　electric　energy　changing　into　kinetic　energy,　thermal　energy　and　magnetic　field　energy.　If　the　input　energy　is　more　than　the　expended　energy,　then　the　excess　energy　will　be　exhibited　as　bounce　of　contacts　and　cores.　Therefore,　controlling　the　input　energy　and　the　distribution　of　each　kind　of　energy　in　the　closing　process　will　result　in　significant　reduction　in　contact　bounce.　In　addition,　the　electrical　endurance　and　the　overall　performance　will　be　improved.　Selecting　one　kind　of　AC　contactor　which　applied　in-air　condition　as　prototype　in　this　paper.　The　energy　distribution　of　contactor　is　analyzed　based　on　the　3D　dynamic　simulation　system.　Then,　the　energy　calculation　model　is　developed　and　verified　through　the　experiment.