The "Ferro and Regulator Replacement" (FARR) power supply is characterized by its ability to maintain a constant d-c output voltage with variations in the power line input, such as during a "brownout" condition. Two modeling techniques were used to evaluate design features and performance. The primary method of analysis is a computer simulation model of the representative circuits. This simulation adequately represents the FARR power supply for both steady state and transient power supply operations. Auxiliary analytical models were also programmed to determine ideal signal waveforms and circuit values required to compensate for dynamic behavior under various power line conditions. Results obtained from the analytical models were tested in the more realistic simulation model. This paper emphasizes the methodology used to analyze and evaluate the FARR power supply.