Numerical Simulation Method on Resistance Projection Welding Control Process

A coupled electrical field-circuit method was introduced to simulate the control process of electrical resistance welding. The circuit method was used to analyze the response of the control system and the field method was adopted to describe the behavior of the welding joint. By using a coupled electrical-thermal-mechanical FEM technology, the relationship of electrical, thermal and mechanical field was established. The coupled FEM analysis is adopted to analyze the behaviors of the welding joint. An equivalent circuit was introduced to combine the dynamic electrical resistance of workpieces, the welding power source and the control characteristics of the system. An updated method was selected to describe the dynamic response of the control system. In every increment, the variables were updated as initial conditions and boundary conditions in the field analysis, or resistance, voltage, current in the circuit analysis. An example was selected as projection welding process.