An electromagnetic pulse welding (EMPW) system is a complex multifield coupling system. Using finite element software to simulate its processes can better guide the design of the electromagnetic pulse welding system and the analysis of the welding mechanism. However, the existing finite element software has a complex model, involves a large amount of calculation, and is time consuming, which is not conducive to the optimization of the welding device. In this paper, an equivalent circuit model based on an improved current wire method is proposed, and the welding process is modeled and analyzed, and then compared with the simulation results of the finite element software COMSOL. The results show that the analytical model is accurate and effective, and it can reduce the calculation time and improve the processing efficiency. Second, based on the equivalent circuit model and taking the maximum impulse of the electromagnetic force as the optimization objective, the shape parameters of the field shaper and the number of turns of the coil in the electromagnetic welding device for plates based on the field shaper are optimized, and the optimal parameters are obtained. Finally, the welding equipment is designed with the optimal parameters, and the electromagnetic welding platform is built. An SS304 stainless steel plate and A1060 aluminum plate with a thickness of 1 mm are welded, and the dissimilar metal plates are well connected. INDEX TERMS Electromagnetic pulse welding; Improved current wire method; Equivalent circuit model; Optimize; Field shaper; Maximum impulse; Welding platform.