Modeling and analysis of switched networks as mixed linear complementarity systems

In this paper, a recently proposed approach for modeling switched networks (SNs) and power electronic converters is presented. Actually, typical modelings of SNs such as switched models (SMs) and the modified nodal analysis (MNA) exhibit certain drawbacks for simulating switching. For example, the SMs, which consider the switches to be ideal, require to obtain a set of dynamical models that describes all circuit topologies and need to calculate the switching instants of electronic devices (EDs) (diodes, thyristors, transistors). Thus, SMs do not consider a complete switched model that calculates by itself the natural switching instants of EDs and that considers their continuous and discontinuous conduction. For models based on the MNA, the analysis adds nonlinear functions of the voltage-current characteristics of EDs. However, this consideration involves iterative processes, which implies a high computational cost. In this paper, mixed and classical linear complementarity systems (LCSs) are validated to form complete switched models that include continuous and dicontinuous conduction of EDs without requiring iterative processes. It is shown that LCSs are useful to compute dynamical and steady-state responses of SNs. In particular, it is seen that the steady-state solution can be obtained in a direct way without requiring iterations and a consistent initial condition, which is a goal in power systems analysis. As example, a controlled buck-boost dc/dc converter is simulated to show the potential of the complementarity framework.