2-DIMENSIONAL POWER DEVICE SIMULATOR CONSIDERING AN INTEGRAL EXTERNALCIRCUIT EQUATION

A two-dimensional power device simulator that takes into account an in tegral external circuit equation and Dirichlet (voltage) boundary cond ition is developed. This simulator has the features of achieving a fas t and stable calculation even when the physical variables (p, n, phi) vary radically, just as does a turnoff performance with an inductive l oad of power devices. We applied this to investigate the IGBT's induct ive turnoff phenomenon and got the calculated waveforms which agreed q ualitatively well with the experimental results. This method can be ex panded for a more-complicated branch circuit, such as a snubber one. T he principle of this method is that we set up the integral equations f or each constituent circuit and solve them with Newton's iteration met hod by satisfying Kirchhoff's law at the point with which each circuit is connected.