Order diminution and its application in controller design using salp swarm optimization technique

Order diminution (OD) or model order reduction (MOR), a very important field of System Engineering, has been explored by many researchers. Different methods are available for reducing the complexity of a control system, which are subsequently utilized to get a cost-effective controller. Model order reduction is done by either using classical methods or by using optimization techniques. In optimization algorithms, accuracy, complexity, and convergent rate are the main criteria for comparison in OD. This paper contributes a novel fast and more accurate OD (MOR) technique based on Salp Swarm Optimization. Further, the proposed method is applied to a time-delay system in four different manners. The effectiveness of the proposed technique is shown by reducing four benchmark systems, including a system with time delay and an 84th order system. Finally, the application of OD is shown by designing a reduced-based H-infinity controller for the 84th order system which results in a great saving of time ( $$\approx 96\%$$ ). The obtained results are comparable or better than those from the existing well-known order reduction techniques available in the literature.