Title | Nonlinear order reduction in dynamic magnetic equivalent circuits of electromechanic actuators: Incorporating relative motion and back EMF |
Publication Type | Conference Paper |
Year of Publication | 2008 |
Authors | Davoudi, A., P. L. Chapman, and J. Jatskevich |
Conference Name | Power Electronics Specialists Conference, 2008. PESC 2008. IEEE |
Pagination | 3992 -3995 |
Date Published | jun. |
Keywords | back EMF, converter-driven actuators, dynamic magnetic equivalent circuits, eddy currents, electric actuators, electromagnetic forces, electromechanic actuators, equivalent circuits, frequency-domain characteristics, magnetic circuits, nonlinear order reduction, nonlinear systems, piecewise linear reduced- order models, power convertors, power electronics converters, reduced order systems, relative motion, time-domain transients |
Abstract | Physics-based modeling of electromechanical actuators driven by power electronics converters is highly desired for precise dynamics representations of magnetic components. In this paper, a very detailed dynamic magnetic-equivalent circuit of an actuator is set forth that is based on geometrical and material characteristics, and avoids conventional geometrical simplifications and uniform flux-density assumptions. In general, the presence of eddy currents in dynamic physics-based models significantly increases the model order. The computational intensity is further pronounced when considering the nonlinearity associated with relative motion. Automated linear and nonlinear order-reduction techniques are introduced to numerically extract the essential system dynamics in the desired bandwidth, thus preserving both dynamic accuracy and computational efficiency. In particular, the original high-order model is replaced with piecewise linear reduced- order models that are expressed as numerical functions of the mechanical position and speed. The model order is successfully reduced from 300 to only 5 state variables, thus significantly cutting the execution time. The resulting reduced-order model is verified with the original full-order model in predicting time-domain transients as well as frequency-domain characteristics, which is important for converter-driven actuators. |
URL | http://dx.doi.org/10.1109/PESC.2008.4592578 |
DOI | 10.1109/PESC.2008.4592578 |