INVERTER DC RESISTANCE SPOT WELDING SYSTEM, CONTROL METHOD FOR WELDING PROCESS THEREOF AND DESIGN METHOD FOR FUZZY CONTROLLER THEREOF

摘要

PURPOSE: An inverter DC resistance spot welding system, a control method for welding processes thereof, and a design method for a fuzzy controller thereof are provided to allow a user to implement stable welding by controlling the welding processes using embedded software. CONSTITUTION: An inverter DC resistance spot welding system comprises a power converting unit(130), a welding transformer unit(170), a welding unit(190), and a welding unit controller(110). The power converting unit creates welding current and controls the amount or application time of the welding current. The welding transformer unit creates large current delivered to a welded object. The welding unit comprises a welding gun that transfers an electrode pressing force to the welded part of the welded object and a pneumatic device that exerts the electrode pressing force. The welding unit controller controls the operation of the welding unit. The power converting unit comprises a rectifier diode that rectifies three-phase AC power, a condenser that smoothes the rectified power to form DC current, and an inverter that changes the DC current into AC current with a specified pulse width.