1. 17-1 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications Chapter 17 Electric Utility Applications These applications are growing rapidly

2. 17-2 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications HVDC Transmission There are many such systems all over the world

3. 17-3 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications HVDC Poles Each pole consists of 12-pulse converters

4. 17-4 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications HVDC Transmission: 12-Pulse Waveforms Idealized waveforms

5. 17-5 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications HVDC Transmission: Converters Inverter mode of operation

6. 17-6 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications Control of HVDC Transmission System Inverter is operated at the minimum extinction angle and the rectifier in the current-control mode

7. 17-7 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications HVDC Transmission: DC-Side Filters Tuned for the lowest (12 th harmonic) frequency

8. 17-8 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications HVDC Transmission: AC-Side Filters Tuned for the lowest (11 th and the 13 th harmonic) frequencies

9. 17-9 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications Effect of Reactive Power on Voltage Magnitude Illustration of the basic principle

10. 17-10 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications Thyristor-Controlled Inductor (TCI) Increasing the delay angle reduces the reactive power drawn by the TCI

11. 17-11 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications Thyristor-Switched Capacitors (TSCs) Transient current at switching must be minimized

12. 17-12 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications Instantaneous VAR Controller (SATCOM) Can be considered as a reactive current source

13. 17-13 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications Characteristics of Solar Cells The maximum power point is at the knee of the characteristics

14. 17-14 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications Photovoltaic Interface This scheme uses a thyristor inverter

15. 17-15 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications Harnessing of Wing Energy A switch-mode inverter may be needed on the wind generator side also

16. 17-16 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications Interface with 3-Phase Utility Grid Uses a thyristor inverter

17. 17-17 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications Interface of SMES Can be used for utility load leveling

18. 17-18 Copyright © 2003 by John Wiley & Sons, Inc. Chapter 17 Electric Utility Applications Active Filters for Harmonic Elimination Active filters inject a nullifying current so that the current drawn from the utility is nearly sinusoidal