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A Modified Particle Swarm Optimization Based Approach for Lower Order Model Formulation of Linear Time Invariant Systems

S.N. Deepa, G. Sugumaran

Abstract


This paper proposes a computationally simple approach for model formulation of linear time invariant systems. New version of the particle swarm optimization (PSO), namely, MPSO is used for the lower order model formulation of linear time invariant systems. In the modified PSO, the movement of a particle is governed by three behaviors, namely, inertia, cognitive, and social. The cognitive behavior helps the particle to remember its previous visited best position. This paper proposes to split the cognitive behavior into two sections .This modification helps the particle to search the target very effectively. In order to minimize the integral squared error of the lower order model, MPSO is proposed and results are shown in the form of unit impulse response curves and are compared with the response of the original higher order model and with the other model formulation methods. The proposed method is illustrated through numerical examples from literature.

Keywords


Higher Order Model, Integral Squared Error, Lower Order Model, Modified Particle Swarm Optimization, Single Input Single Output

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