PN Diode model Based on Divided Charge Distribution For EMTP-Type Simulators

Abstract

A physical-based model of a pn diode is extremely important for a successful design and development of not only electronic circuits but also power electronics systems such as a HVDC (high voltage direct current) system or FACTS (flexible ac transmission system), because the pn diode is a basic semiconductor device. This paper has proposed a pn diode model based on divided charge distribution for EMTP-type simulators such as EMTP and EMTDC. The proposed model physically represents drift and diffusion phenomena of a pn diode in model equations accurately to realize steady and transient characteristics including the forward and reverse recovery characteristics in the EMTP-type simulators. It has been also explained how the model parameters influence the diode voltage and current of the proposed pn model. With the diode voltage and current, the transient characteristic of the model variables have been also presented to understand a relation between the physical meanings of a diode and the model variables in the proposed model. Results calculated with a combined iterative method show a satisfactory coincidence with measured results.