SIMULATION OF THE INTERELECTRODE GAP IN ELECTRICAL DISCHARGE GRINDING WITH CHANGING ELECTRODE POLARITY

Abstract

In this paper, an experimental study and simulation in the Simulink graphical environment of the interelectrode gap during electroerosive grinding with changing polarity of electrodes of difficult-to-machine materials was carried out. Based on the experimentally obtained oscillograms of currents and voltages in the cutting zone, a simulation model of the interelectrode gap has been developed. The model implements a nonlinear dependence of the active resistance of the interelectrode gap on its value, which makes it possible to take into account the influence of the interelectrode medium on the parameters of electric discharge pulses. As a result of the analysis of the experimental oscillograms of the currents of the working pulses, it was found that the electrical processes occurring in the interelectrode gap during electroerosive grinding are oscillatory. The environment in which these processes take place can be represented with sufficient accuracy in the form of a T-shaped equivalent circuit, which includes active resistances, inductances and capacitance. It has been established that the active resistance of the interelectrode gap depends nonlinearly on its value. The root-mean-square deviation between the calculated and experimental current and voltage pulses, referred to its steady-state value, does not exceed 12-15%. The found values ​​of the equivalent circuit parameters made it possible to obtain a Simulink model of the interelectrode gap in electroerosive grinding. A good agreement between the calculated oscillograms obtained in the Simulink model and the experimental ones showed that the developed model of the interelectrode gap during electroerosive grinding quite adequately reflects the real electrical processes occurring in the interelectrode gap.