Some contributions to Lagrangian modelling of Power Converters

Abstract

Lagrangian modelling can be used to derive mathematical models for complex power electronic converters. This approach uses scalar quantities (kinetic and potential energy) to derive models, which is simpler than using (vector-based) force balance equations. It employs generalized coordinates, making it easier to deal with complex systems with constraints. This systematic approach results in equations that can be expressed in state-space form, which allows for the simplification of the simulation and design process and the use of many standard software packages for system analysis and simulation. In this work, contributions are made regarding the procedure to be followed for the Lagrangian modelling of power converters and the incorporation of constraints within the Lagrangian framework. Furthermore, for the first time, Lagrangian modelling is extended to non-ideal, high-fidelity descriptions of standard power electronic circuits.

Figures (11)

• Figure 1: Procedure for obtaining state space representation of switched electrical circuits using EL formulation
• Figure 2: Simple diode circuit
• Figure 3: Example Circuit
• Figure 4: LC circuit
• Figure 5: H-F inductor and capacitor model