An Incremental Charge Method for the Analysis of Nonlinear Circuits

摘要

Conventional numerical methods for nonlinear transient circuit analysis apply standard numerical procedures to the equations obtained from Kirchhoff's laws. In this thesis is developed a method of analysis in which only one of Kirchhoff's laws is forced to hold and the other is used to make numerical corrections. The method developed assumes that the current law holds and the voltage law may be violated. To obtain sufficiently simple numerical formulas, a circuit with a tree-type topology is assumed. Relying on this the basic charge distribution and node voltage calculation formulas are derived for the general branch which may consist of a resistance, a capacitance, an inductance, a voltage source or any series combination of these. Since this method favors current controlled nonlinear elements, an analogous but more restricted method for conveniently including votage-controlled devices is developed. A brief discussion of errors and their compensation and of stability is included. Because of the importance of diodes and transistors, the technique by which they can be efficiently analyzed by the method is developed. The advantages are that the method provides for the models the means for making numerical corrections. A technique by which transmission lines can be handled is also described. A program based on this method is presented through a brief description.