Design Optimization of Doubly Fed Induction Generator Performance by Differential Evolution
Doubly-fed induction generators (DFIG) due to their advantages like speed variation and four-quadrant operation, find its application in wind turbines. DFIG besides supplying power to the grid has to support reactive power (kvar) under grid voltage variations, should contribute minimum fault current during faults, have high efficiency, minimum weight, adequate rotor protection during crow-bar-operation from +20% to -20% of rated speed. To achieve the optimum performance, a good electromagnetic design of DFIG is required. In this paper, a simple and heuristic global optimization – Differential Evolution has been used. Variables considered are lamination details such as slot dimensions, stack diameters, air gap length, and generator stator and rotor stack length. Two operating conditions have been considered - voltage and speed variations. Constraints included were reactive power supplied to the grid and limiting fault current and torque. The optimization has been executed separately for three objective functions - maximum efficiency, weight reduction, and grid fault stator currents. Subsequent calculations led to the conclusion that designs determined through differential evolution help in determining an optimum electrical design for each objective function.
 R Storn and K Price, “ Differential Evolution - A Simple and Efficient Heuristic for Global Optimization over Continuous Spaces” Journal of Global Optimization 11(4):341-359, Jan. 1997
 R Storn and K Price, “Differential Evolution-A Simple and Adaptive scheme for Global Optimization over Continuous Spaces”: Journal of Global Optimization, 23(1), January 1995
 Stjepan Stipetic and Werner Miebach, Biviers, France and Damir Zarko, Croatia, “Optimization in Design of Electric Machines: Methodology and Workflow” 2015, ACEMP-OPTIM-ELECTROMOTION joint conference.
 M. G. Say, “Performance and Design of A.C Machines”
 Philip Langdon Alger, “ Nature of Polyphase Induction Machines”
 Johan Morren and Sjoerd W H de Haan, “Short Circuit of Wind Turbines with Doubly Fed Induction Generator.” IEEE Transactions on Energy Conversion, 22(1):174-180, March 2007
 J. Mc, C.A. Calley. “Double-fed electric machines-steady state analysis” A ppt presentation
 Mamidi Ramakrishna Rao, “Optimization of DFIG Equivalent Circuit Parameters by Direct Search Method”, World Academy of Science, Engineering and Technology. International Journal of Electrical and Computer Engineering, 11(6), 2017
 Likin Simon and K Shanti Swarup, “ Impact of DFIG based Wind Energy Conversion System on Fault studies and Power Swings”, 2016 19th National Power Systems Conference (NPSC), India
 Jouni Lampinen and Ivan Zelinka, “Mixed Integer-Discrete-Continuous Optimization By Differential Evolution” Part 1 and Part 2.