A method for predicting the transient and steady-state characteristics of electrical power systems on Spice is presented. The analysis method presented significantly reduces computer memory requirements and run-time. The results correlate with more detailed models that require extensive computer resources and significant run-time. This paper extends the original work presented in a 1992 IECEC paper written by the authors [6]. Specifically, the negative impedance characteristic of constant power loads has been added to the technique. This provides a more realistic simulation for electrical power systems that are dominated by load power converters.