State Space Modeling, Analysis, and Simulation of Switched RLCM Networks

Open Access
Author:
Albeaik, Saleh
Graduate Program:
Electrical Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
April 01, 2014
Committee Members:
  • Jeffrey Scott Mayer, Thesis Advisor
Keywords:
  • state space
  • modeling
  • analysis
  • simulation
  • switched RLCM
  • ideal switches
  • software design
Abstract:
The design process for power converters and electromechanical drives would be enhanced by the availability of modeling software that represents the fundamental nature of these systems, namely, switch-mode operation of the semiconductor devices. Established network simulation programs, such as SPICE and its many descendants, utilize a combination of companion models and modified nodal analysis (CM + MNA) that permits very simple implementations of algorithms for simulating the dc, ac, and transient response of most electrical networks. In the early days of computer modeling, the simplicity of these algorithms was critically important while the attention being given to networks with switch-mode operation was modest and focused on digital logic. Thus, SPICE (CM + MNA) became the de facto standard for network simulation. It can be used for transient simulation of power converters, but it is inherently slow and can provide little insight beyond the raw time-domain response of the converter. These limitations can be addressed by replacing CM + MNA with state space modeling (SSM). Ideal switches, the main subject of this thesis, impose computational difficulty to simulation software. The ideal behavior is extremely non-linear, potentially causing impulses to exist in the network. Moreover, to employ piecewise linear analysis techniques, switch conduction state dependencies must be resolved. The thesis offers a computationally efficient method to handle the presence of impulses as an alternative to more complex approaches presented in literature. Analyzing the presence and the effect of impulses efficiently makes resolving switch state dependencies using the common iterative search algorithm feasible. Simulation software based on this thesis was designed and implemented. An overview of the software design is presented towards the end.