ECS-9703449 Maksimovic The objective of this project is to develop numerical techniques for computer aided analysis, modeling, syntheses and design of power electronic systems, and to integrate the developed tools in the power-area curriculum. In the first phase of the project, numerical techniques and a simulation tool are developed for piecewise-smooth systems. Piecewise-smooth (PWS) system modeling is proposed as the general approach that includes full range of modeling options: from idealized piecewise-linear (PWL) models suitable for fast transient simulation over many switching cycles, to detailed nonlinear models for accurate predictions of waveforms within a switching cycle. As a result, the developed PWS simulator is able to perform a complete range of simulation tasks and to aid analysis and design of a wide range of power electronic applications including power system and utility interfaces, motor drives, renewable energy systems and switching power supplies. The PWS simulator is based on new numerical techniques including: unified representation of PWL, PWS and smooth nonlinear elements to obtain a constant system matrix, efficient iteration over nonlinearity using numerical continuation methods, and a PWS state determination algorithm to eliminate convergence problems around fast switching transitions. The second phase of the project concentrates on applications and extensions of the PWS .simulator: (1) comprehensive computer-aided steady-state analysis of switching power converters, including general, efficient and robust algorithms for finding periodic steady-state solution, tracing steady-state characteristics over a range of parameters, and tracing operating-mode boundaries in the parameter space; (2) automated small-signal and large-signal dynamic modeling of power electronic systems; (3) a framework for higher-level CAD tools such as synthesis, tolerance analysis and design optimization tools. The developed techniques are implemented in software suitable for use in power electronics and power systems research, development and education. The tools are integrated into two undergraduate power-area courses - an Energy Conversion lecture course and a new, hands-on Power Electronics laboratory. A set of interactive WEB pages is developed to combine on-line simulation tools with supporting laboratory and course materials.
