International Journal of Electrical and Computer Engineering (IJECE) Vol. 10, No. 5, October 2020, pp. 5123~5130 ISSN: 2088-8708, DOI: 10.11591/ijece.v10i5.pp5123-5130  5123 Journal homepage: http://ijece.iaescore.com/index.php/IJECE Optimal power generation for wind-hydro-thermal system using meta-heuristic algorithms Thuan Thanh Nguyen 1 , Van-Duc Phan 2 , Bach Hoang Dinh 3 , Tan Minh Phan 4 , Thang Trung Nguyen 5 1 Faculty of Electrical Engineering Technology, Industrial University of Ho Chi Minh City, Vietnam 2 Faculty of Automobile Technology, Van Lang University, Vietnam 3,5 Power System Optimization Research Group, Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Vietnam 4 Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Vietnam Article Info ABSTRACT Article history: Received Mar 25, 2019 Revised Apr 27, 2020 Accepted May 8, 2020 In this paper, cuckoo search algorithm (CSA) is suggested for determining optimal operation parameters of the combined wind turbine and hydrothermal system (CWHTS) in order to minimize total fuel cost of all operating thermal power plants while all constraints of plants and system are exactly satisfied. In addition to CSA, Particle swarm optimization (PSO), PSO with constriction factor and inertia weight factor (FCIW-PSO) and social ski-driver (SSD) are also implemented for comparisons. The CWHTS is optimally scheduled over twenty-four one-hour interval and total cost of producing power energy is employed for comparison. Via numerical results and graphical results, it indicates CSA can reach much better results than other ones in terms of lower total cost, higher success rate and faster search process. Consequently, the conclusion is confirmed that CSA is a very efficient method for the problem of determining optimal operation parameters of CWHTS. Keywords: Cuckoo search algorithm Fitness function Hydrothermal system Total fuel cost Wind turbine Copyright © 2020 Institute of Advanced Engineering and Science. All rights reserved. Corresponding Author: Thang Trung Nguyen, Power System Optimization Research Group, Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, 19 Nguyen Huu Tho street, Tan Phong ward, District 7, Ho Chi Minh City, Viet Nam. Email: nguyentrungthang@tdtu.edu.vn NOMENCLATURE Ntp Number of thermal units Nin Number of scheduled intervals ki, mi, ni Coefficient of fuel cost function  , , PHk,j, PWw,j Generation of the ith thermal unit, the kth hydro unit and the wth wind turbine at the jth interval Ntp, Nhp, Nwt, Nin Number of thermal units, hydro units, wind turbines and intervals. Pload,j, Ploss,j Power of load and loss at the jth interval PWw, PWw,rate Generation and rated generation of the wth wind turbine WV, WVrate, WVcut-in, WVcut-out Wind speed, rated wind speed, cut-in speed and cut-out speed PWw,min, PWw,max Minimum and maximum generation of the wth wind turbine Xk ,Yk, Zk coefficients of the kth hydro unit’s generation Qk,min, Qk,max Minimum and maximum discharge of the kth hydro unit Qk,j Discharge of the kth hydro unit at the jth interval Wavai,k available water for power generation over the scheduled intervals