Abstract—High Speed PM Generators driven by micro-turbines are widely used in Smart Grid System. So, this paper proposes comparative study among six classical, optimized and genetic analytical design cases for 400 kW output power at tip speed 200 m/s. These six design trials of High Speed Permanent Magnet Synchronous Generators (HSPMSGs) are: Classical Sizing; Unconstrained optimization for total losses and its minimization; Constrained optimized total mass with bounded constraints are introduced in the problem formulation. Then a genetic algorithm is formulated for obtaining maximum efficiency and minimizing machine size. In the second genetic problem formulation, we attempt to obtain minimum mass, the machine sizing that is constrained by the non-linear constraint function of machine losses. Finally, an optimum torque per ampere genetic sizing is predicted. All results are simulated with MATLAB, Optimization Toolbox and its Genetic Algorithm. Finally, six analytical design examples comparisons are introduced with study of machines waveforms, THD and rotor losses. Keywords—High Speed, Micro - Turbines, Optimization, PM Generators, Smart Grid, MATLAB. I. INTRODUCTION HE Smart Grid Energy Systems (SGES) is recently increasing, particularly onsite generation [1]. This interest is because larger power plants are economically unfeasible in many regions due to increasing system and fuel costs, and more strict environmental regulations. In addition, recent technological advances in small generators, Power Electronics, and energy storage devices have provided a new opportunity for distributed energy resources at the distribution level [1-3]. So, more attention has been paid to the development of high speed PM generators driven by micro-turbines, as prime movers with local conversion at load points [4]. High speed permanent magnet (PM) generators provide a substantial reduction in size and weight over other types of generators, and they are also higher in power density, since, as the speed of a machine increases, its size decreases for a given output power. Size, weight, and cost are the major factors for successful design. For high-speed applications, the rotor aspect ratio, defined as length-to-diameter, is a critical parameter. A. El Shahat is with Department of Electrical and Computer Engineering, Mechatronics-Green Energy Lab., Dreese Labs, The Ohio State University, 43210, USA (Corresponding author, fax : +1 (614) 292 - 7596, tel: +1 (614) 599 – 3864, e-mail: adel.elshahat@ieee.org, ahmed.210@osu.edu). A. Keyhani is with Department of Electrical and Computer Engineering, Mechatronics-Green Energy Lab., Dreese Labs, The Ohio State University, 43210, USA . H. El Shewy is with Department of Electrical Power and Machines Engineering, Faculty of Engineering, Zagazig University, Zagazig, Egypt. Stator core losses may be minimized by using laminated steel in stator construction and by not generating frequencies that are too high. The main applications of PMSG are for power generation as part of renewable energy resources and main generators for aircraft, etc. [5-12]. The sizing of HSPMSG design must address system topology for good power/volume, low cost, and superior efficiency. The influence of the choice of stator lamination material on iron loss in a high speed, high power, and permanent magnet generator is investigated. We study the optimum design of high speed PM alternators for applications in distributed power generation systems [4-17]. The high speed PM machine has been widely used in distributed power generation. The high speed generator distributed generation system, in comparison with the PM doubly-fed reluctance generator, for the same application, has better electromagnetic properties, and (the PM doubly-fed reluctance machine exhibits better mechanical behavior [25]. Aspects of PM motor technology and the design of brushless PM machines, as introduced in Hanselmann [15] and Hendershot [16], are used in this paper. Fig. 1 Smart Grid System with Micro Turbine Power Station [1]. 400 kW Six Analytical High Speed Generator Designs for Smart Grid Systems A. El Shahat, A. Keyhani and H. El Shewy T World Academy of Science, Engineering and Technology International Journal of Electrical and Computer Engineering Vol:4, No:3, 2010 676 International Scholarly and Scientific Research & Innovation 4(3) 2010 scholar.waset.org/1307-6892/5063 International Science Index, Electrical and Computer Engineering Vol:4, No:3, 2010 waset.org/Publication/5063