A　transverse　rotating　magnetic　field　generator　is　designed,　in　which　the　rotating　speed　and　the　maximum　amplitude　of　magnetic　flux　density　are　separately　controlled　by　frequency　of　carrier　wave　and　duty　cycle　of　modulated　wave.　Based　on　theoretical　analysis　and　test,　the　moving　mechanism　of　TIG　arc　is　found　when　applying　the　generator　to　TIG.　The　experiment　results　show　not　only　the　TIG　arc　is　regularly　rotating　and　offsetting,　but　also　both　the　rotating　speed　and　the　rotating　radius　are　variable.