The dynamic behavior of electromagnetic plunger drivers for electrical apparatusses with contacts

The paper presents a numerical model for electromagnetic plunger drivers commonly used for electrical commutation apparatuses (EAC) described as electromechanical systems (a mechanism driven by an electromagnet). Starting from energy conservation equations applied to the electromechanical assembly on can define the differential equations system, which mathematical describe the EAC dynamic regime. Due to the fact that the non-linear differential equations system has not analytical solutions, the system must be integrated using a numerical method. The mathematical system is formally the same for the connecting/disconecting regime of EAC, and permits to emphasize the influence of diverse parameters on the transient process of the electromechanical system. Finally, is possible to control and optimize the factors of interest for the circuit commutation (connecting and disconnecting time, contact speed and electromagnetic plunger parameters especially for the ultrafast switchers). In order to sustain the mathematical model, the differential equations have been written for a DC switcher and the data obtained from the numerical calculus had been compared with the experimental data.