Incorporation of non-linear dynamics to the observability formulation of shipboard power systems

Perturbations in shipboard power systems can make controllers useless if improper control strategies are used. Incorporating the nonlinear dynamics of the shipboard power system in the control methodology is the solution to this problem. Before this solution is designed, the concept of nonlinear observability should be first investigated. The proposed observability formulation accounts for non-linearities and provides a more comprehensive observability determination. A simplified model of a shipboard power system that incorporates machines and power electronics converter dynamics is developed and the observability formulation as applied to this system model investigated. A measure of observability is presented through different case studies were loading condition effects are analyzed. This ultimately will lead to the development of system observers for dynamic state estimation and nonlinear control techniques, giving the power system designer/operator the ability to acquire knowledge related to the state of the system during transitions from the desired operating points.