Most motors are designed to operate at a constant speed and provide a constant output; however, modern technology requires different speeds in many applications where electric motors are used. A variable speed drive (VSD) is a device that regulates the speed and rotational force, or output torque of mechanical equipment. Effects of applying VSDs are in both productivity improvements and energy savings in pumps, fans, compressors and other equipment. Variable speed drive technology and the importance of controlling the speed of existing motors have fascinated many attentions in the last years with the advent of new power devices and magnetic materials. This paper is a comprehensive review on applications of VSD in electrical motors energy savings

1. Under the Esteemed Guidance of
Mr. J Suresh
Associate Professor
Presented by:
G. Swetha
19ME1D4305
1
Dept.of EEE, RCE
DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING
RAMACHANDHRA COLLEGE OF ENGINEERING
ELURU-534007.

2.  Objective of Project
 Introduction
 Main components of block diagram
 Proposed Converter Topology
 Operating Modes
 Dynamic Modeling And Control
 Simulink model
 Results
 Conclusions
 References

3. OBJECTIVE OF THE PROJECT:
 Variable nature of wind and fluctuating load profiles make the operation of
wind based power systems challenging, particularly when they operate in
standalone mode.
 The random variation of wind speed leads to fluctuating torque of the wind
turbine generator resulting in voltage and frequency excursions in the Remote
Area Power Supply (RAPS) system
 Integration of an Energy Storage System (ESS) into a wind based power
system provides an opportunity for better voltage and frequency response,
specially during wind and load demand variations.
 A Proposed RAPS system consisting of Permanent Magnet Synchronous
Generator (PMSG), Fuzzy controlled Rectifier-Inverter arrangement, Hybrid
Energy Storage (HES) system, Main load and Utility grid is considered in this
work.
Dept.of EEE, RCE 3

4. OBJECTIVE OF THE PROJECT:
 A coordinated control approach is developed to manage both Active and
Reactive power flows, and individual controllers for each RAPS component
are also developed for better performance.
 This Proposed system is capable of achieving the following objectives: 1)
Robust voltage and frequency regulation, 2) Effective management of HES
system, 3) Reactive power support.
 This entire system is implemented in MATLAB/Simulink software.
Dept. of EEE, RCE 4

5. Problems addressed in this work :
 To design and develop a Z-source inverter based grid-interface for a variable-speed
wind turbine connected to a permanent magnet synchronous generator.
 To design and develop a control system to harvest maximum wind energy under
varied wind conditions with the use of a permanent magnet synchronous generator, a
diode-rectifier and a Z-source inverter.
 To include hybrid energy storage system with battery and super capacitor to harvest
maximum wind energy.
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6. BLOCK DIAGRAM OF ISLANDED MODE OF WIND POWER
GEENRATING SYSTEM (CONVENTIONAL SYSTEM):
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7. BLOCK DIAGRAM OF GRID CONNECTED MODE OF WIND
POWER GEENRATING SYSTEM (PROPOSED SYSTEM):
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8. Z Source Inverter topology
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 A Z-source inverter is a type of power inverter, a circuit that
converts direct current to alternating current (DC-AC).
 It functions as a buck-boost inverter without making use of DC-DC
converter bridge due to its unique circuit topology.
 Impedance (Z) Source networks provide an efficient means of power
conversion between source and load in a wide range of electric power
conversion applications (DC–DC, DC–AC, AC–DC, AC– AC)

9. Z Source Inverter topology Vs Traditional topology
Dept.of EEE, RCE 9
Traditional two-stage power conversion
Proposed Z Source based power conversion

10. Z Source Inverter topology used in this work
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11. Control scheme of the Z-source inverter based wind
power generation system
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12. Energy Storage System (ESS):
The hybrid energy storage system consists of
A battery storage
A super capacitor
An energy management algorithm (EMA) is proposed for the
hybrid energy storage with a view to improve the performance of the
battery storage.
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13. Hybrid energy storage system in a PMSG based RAPS system.
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14. Energy management algorithm for hybrid energy storage system
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15. Control Coordination Methodology
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16. Dept.of EEE, RCE
Load Side Converter control scheme
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17. Dump load controller
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18. Dept.of EEE, RCE 18
Simulink model of Stand alone Wind Power Generating
System with Energy storage

19. Simulink model of Grid Interfaced Wind Power Generating
System
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20. Dept.of EEE, RCE
Wind Speed & Voltage at load side
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21. Dept.of EEE, RCE
Frequency at load side & DC link Voltage
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22. Dept.of EEE, RCE
Wind Power, Battery power, Super capacitor power, Dump load
power and Load demand
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23. Dept.of EEE, RCE 23
Reactive power sharing
Currents of battery storage and supercapacitor

24. Fuzzy controlled converter:
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25. Dept.of EEE, RCE
Fuzzy Rules:
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26. Dept.of EEE, RCE
Wind Speed & Voltage at load side
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27. Dept.of EEE, RCE
Frequency at load side & DC link Voltage
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28. Dept.of EEE, RCE
Reactive power sharing
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29. Dept.of EEE, RCE
A wind power integration topology based on Z-source inverter
system is proposed in this project.
With the employment of the proposed Z-source inverter, the
AC-side voltage is maintained constant though the DC-link voltage of
the front end rectifier tends to fluctuate due to the stochastic nature of
the wind.
The DC- and AC-side controllers for the Z-source inverter are
designed. The proposed fuzzy control algorithm is able to manage
power balance in the RAPS system while extracting the maximum
power output from the wind throughout its entire operation.
CONCLUSION :
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30. References:
[1] S. Bhattacharyya (ed.), Rural Electrification Through Decentralised Off-grid
Systems in Developing Countries, Green Energy and Technology, DOI:
10.1007/978-1-4471-4673-5_2, Springer- Verlag London 2013.
[2] M. E. Haque, M. Negnevitsky, and K. M. Muttaqi, “A novel control strategy for
a variable-speed wind turbine with a permanent-magnet synchronous generator,”
IEEE Trans. Ind. Appl., vol. 46, pp. 331–339,Nov. 2009.
[3] M. Singh and A. Chandra, “Control of PMSG based variable-speed wind-battery
hybrid system in an isolated network,” in Proc. Power Energy Soc. Gen. Meet.
(PESGM), Calgary, AB, Canada, Jul. 26–30,2009, pp. 1–6.
[4] N. Mendis, K. Muttaqi, S. Perera, and M. N. Uddin, “A novel control strategy
for stand-alone operation of a wind dominated RAPS system, ”in Proc. IEEE Ind.
Appl. Soc. (IAS) Annu. Meet., Orlando, FL, USA,Oct. 9–13, 2011.
[5] A.Ter- Gazarian, Energy Storage for Power Systems. London, U.K.:Peter
Peregrinus, 1994, pp. 36–36.
[6] B. S. Borowy and Z. M. Salameh, “Dynamic response of stand-alone wind
energy conversion system with battery energy storage to a wind gust,” IEEE Trans.
Energy Convers., vol. 12, pp. 73–78, Mar. 1997.
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[7] C. Abbey and G. Joos, “Supercapacitor energy storage for wind energy applications,”
IEEE Trans. Ind. Appl., vol. 43, no. 3, pp. 769–776,May-Jun. 2007.
[8] H. Jia, Y. Fu, Y. Zhang, and W. He, “A design of hybrid energy storage control system
for wind farms based on flow battery and electric double-layer capacitor,” in Proc. Asia-
Pacific Power Energy Eng. Conf. (APPEEC), Chengdu, China, Mar. 28–31, 2010, pp. 1–6.
[9] A. M. v. Voorden, L. M. R. Elizondo, G. C. Paap, J. Verboomen, and L. v. d. Sluis, “The
application of super capacitors to relieve battery storage systems in autonomous renewable
energy systems,” in Proc. Power Tec, Lausanne, Switzerland, Jul. 1–5, 2007, pp. 479–484.
[10] L. Wei, G. Joos, and J. Bélanger, “Real-time simulation of a wind turbine generator
coupled with a battery supercapacitor energy storage system,” IEEE Trans. Ind. Electron.,
vol. 75, no. 4, pp. 1137–1145,Apr. 2010.
[11] Y. Zhang, Z. Jiang, and X. Yu, “Control strategies for battery/super capacitor hybrid
energy source systems,” in Proc. IEEE on Global Sustain. Energy Infrastructure, Atlanta,
GA, USA, Nov. 17–18, 2008, pp.1–6.
[12] S. Sayeef, N. Mendis, and K. Muttaqi, “Enhanced reactive power support of a PMSG
based wind turbine for a remote area power system,” in Proc. 20th Australian Power Eng.
Conf. (AUPEC2010), Christchurch, New Zealand, Dec. 5–8, 2010, pp. 15.
[13] Nishad Mendis, Kashem M. Muttaqi, and Sarath Perera’s “Management of Battery-
Supercapacitor Hybrid Energy Storage and Synchronous Condenser for Isolated Operation
of PMSG Based Variable-Speed Wind Turbine Generating Systems” IEEE transactions on
smart grid, vol. 5, no. 2, march 2014.
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32. Dept.of EEE, RCE 32