258 Int. J. Computer Aided Engineering and Technology, Vol. 13, Nos. 1/2, 2020 Copyright © 2020 Inderscience Enterprises Ltd. PID controller tuning using hybrid optimisation technique based on Box’s evolutionary optimisation and teacher-learner-based-optimisation V.P. Singh* and N. Patnana Department of Electrical Engineering, National Institute of Technology, Raipur, 492010, India Email: vinaymnnit@gmail.com Email: naresh283@gmail.com *Corresponding author S.P. Singh Department of Electrical Engineering, Indian Institute of Technology, Kanpur, 208016, India Email: sugandhgcet@gmail.com Abstract: In this paper, a hybrid optimisation technique based on Box’s evolutionary optimisation and teacher-learner-based-optimisation (BEO-TLBO) is proposed for proportional-integral-derivative (PID) controller tuning of level control of three-tank system. The integral-square-error (ISE) of unit step response is minimised for obtaining optimal controller parameters. The ISE is designed in terms of alpha and beta parameters. In BEO-TLBO, a global search is first carried out over the entire search space to determine the set of desired controller parameters using teacher-learner-based-optimisation (TLBO). The search is then refined in the second stage using Box’s evolutionary optimisation (BEO). The results obtained using BEO-TLBO are compared with other existing techniques. Computer simulations reveal that the hybrid optimisation based approach meets the desired specifications with greater accuracy as compared to the other existing methods. Keywords: Box’s evolutionary optimisation; BEO; ISE; optimisation; PID controller; teacher-learner-based-optimisation; TLBO. Reference to this paper should be made as follows: Singh, V.P., Patnana, N. and Singh, S.P. (2020) ‘PID controller tuning using hybrid optimisation technique based on Box’s evolutionary optimisation and teacher-learner-based-optimisation’, Int. J. Computer Aided Engineering and Technology, Vol. 13, Nos. 1/2, pp.258–270. Biographical notes: V.P. Singh graduated from Uttar Pradesh Technical University, Lucknow, India in 2007 with BTech. degree in Electrical Engineering. He received his MTech degree in Control and Instrumentation and PhD degree in Electrical Engineering in 2009 and 2013, respectively, from Motilal Nehru National Institute of Technology, Allahabad, India. Currently, he is working as an Assistant Professor in National Institute of Technology, Raipur, India. His research interests include interval systems, model order reduction and applications of optimisation.