FLYWHEEL ENERGY STORAGE SYSTEM

A COMPLETE PROFESSIONAL PROJECT PRESENTATION ON FLYWHEEL ENERGY STORAGE SYSTEM.

1. FLYWHEEL ENERGY STORAGE SYSTEM

2. CONTENTS INTRODUCTION MAIN COMPONENTS WORKING APPLICATIONS ADVANTAGES AND DISADVANTAGES CONCLUSION REFERENCE

3. INTRODUCTION A Flywheel is simply amass rotating about an axis Flywheels store energy in the form of kinetic energy

4. One of the promising technologies for replacing conventional lead acid batteries and energy storage systems The built in motor provides the electrical input to accelerate the rotor Returns the electrical energy by using this same motor as a generator

5. MAIN COMPONENTS There are 5 main components: Flywheel Motor/ generator Power electronics Magnetic bearings External inductor

6. FLYWHEEL flywheels store energy in a rotating mass of steel of composite material Mechanical inertia is the basis of storage method Use of motor/generator , energy can be cycled(absorbed and then discharged) MOTOR/GENERATOR Permanent magnet(PM) machines have the most advantages, including higher efficiency and smaller size when compared with other types of motors/generators of same power rating PM exhibit lower rotor losses and lower winding inductance The motor/generator is designed to be operated at high speed for minimum system size

7. POWER ELECTRONICS F E S S is the three-phase IGBT-based PWM inverter/rectifier The IGBT is a solid-states device with ability to handle voltages up to 6.7 kv, currents upto 1.2 kA MAGNETIC BEARINGS Magnetic bearings consist of permanent magnets, Which support the weight of the flywheel by repelling force and electromagnets are used to stabilize The best performing bearing is the high-temperature super-conducting(HTS) magnetic bearing, which can situate the flywheel automatically without need of electricity HTS magnets require cryogenic cooling by liquid nitrogen

8. EXTERNAL INDUCTOR The high speed PM offers low inductance The low inductances result in high total harmonic distortion(THD) which increases the machine power losses and temperature Using an external inductor in series with the machine in charging mode is necessary to reduce the THD and bring and bring it within an accepted range

9. WORKING The FESS is made up of a heavy rotating part, the flywheel, with an electric motor/generator. The inbuilt motor uses electrical power to turn at high speeds to set the flywheel turning at its operating speed. This results in the storage of kinetic energy.  When energy is required, the motor functions as a generator, because the flywheel transfers rotational energy to it. This is converted back into electrical energy, thus completing the cycle. As the flywheel spins faster, it experiences greater force and thus stores more energy.

10. APPLICATIONS Hybrid and electric vehicles Light rail power Power quality/ UPS Industrial pulsed power

11. ADVANTAGES High power density High energy density The lifetime of the flywheel is almost independent of the depth of the charge and discharge cycle No periodic maintenance is required Short recharge time

12. DISADVANTAGES Material limits at around 700M/s tip speed Potentially hazardous failure modes Short discharge time

13. CONCLUSION The state of charge can be easily be measured, since it is given by the rotational velocity Environmental friendly materials Low environmental impact

14. REFERENCE T. Aanstoos , J. P. Kajs , W. Brinkman, H. P. Liu, A. Ouroua , and R. J. Hayes, “High voltage stator for a flywheel energy storage system,” IEEE Trans. Magazine, vol. 37, no. 1, pp. 242-247, 2001. I. Vajed , Z. Kohari , L. Benko , V. Meerovich , and W. Gawalek , “Investigation of joint operation of a superconducting kinetic energy storage (Flywheel) and solar cells,” IEEE Transactions on Applied Superconductivity, vol. 13, no. 2, Jun. 2003. B. Bolund , H. Bernhoff , and M. Leijon , “Flywheel energy and power storage System,” Renewable and Sustainable Energy Reviews, vol. 11, no. 2, pp. 235-258, 2007. J. C. Zhang, L. P. Huang, Z. Y. Chen, and S. Wu, “Research on flywheel energy storage system for power quality,” in Proc. International Conference on Power System Technology, 2002, pp. 496-499. [ J. C. Zhang, Z. Y. Chen, L. J. Cai , and Y. H. Zhao, “Flywheel energy storage system design for distribution network,” in Proc. IEEE Power Engineering Society Winter Meeting, 2000, pp. 2619-2623 .