ABSTRACT
This paper deals with the performance analysis of a
two-level, 24-pulse Voltage Source Converters (VSCs) for High Voltage DC (HVDC)
system for power quality improvement. A two level VSC is used to realize a
24-pulse converter with minimum switching loss by operating it at
fundamental frequency switching (FFS). The
performance of this converter is studied on various issues such as steady state
operation, dynamic behavior, reactive power compensation, power factor
correction, and harmonics distortion. Simulation results are presented for a
two level 24-pulse converter to demonstrate its capability.
KEYWORDS
1.
Two-Level
Voltage Source Converter
2.
HVDC
3.
Multipulse
4.
Fundamental
Frequency Switching
5.
Harmonics
SOFTWARE:
MATLAB/SIMULINK
BLOCK DIAGRAM:
Fig.
1 A 24-Pulse voltage source converter based HVDC system
Configuration
EXPECTED SIMULATION RESULTS
Fig.
2 Synthesis of Stepped AC voltage waveform of 24-pulse VSC.
Fig.
3 Steady state performance of proposed 24-pulse voltage source
Converter
Fig.
4 Dynamic performance of proposed 24-pulse voltage source converter
Fig.
5 Waveforms and harmonic spectra of 24-pulse covnerter i) supply
voltage
ii) supply current (iii) converter voltage
CONCLUSION
A
two level, 24-pulse voltage source converter has been designed and its
performance has been validated for HVDC system to improve the power quality
with fundamental frequency switching. Four identical transformers have been used
for phase shift and to realize a 24-pulse converter along with control scheme
using a two level voltage source converter topology. The steady state and
dynamic performance of the designed converter configuration has been
demonstrated the quite satisfactory operation and found suitable for HVDC
system. The characteristic harmonics of the converter system has also improved
by the proposed converter configuration with minimum switching losses without
using extra filtering requirements compared to the conventional 12-pulse
thyristor converter.
REFERENCES
[1]
J. Arrillaga, “High Voltage Direct Current Transmission,” 2nd Edition, IEE
Power and Energy Series29, London, UK-1998.
[2]
J. Arrilaga and M. Villablanca, “24-pulse HVDC conversion,” IEE Proceedings
Part-C, vol. 138, no. 1, pp. 57–64, Jan. 1991..
[3]
Lars Weimers, “HVDC Light: a New Technology for a better Environment,” IEEE
Power Engineering Review, vol.18, no. 8, pp. 1920-1926, 1989.
[4]
Vijay K. Sood, “HVDC and FACTS Controller, Applications of Static Converters in
Power Systems”, Kluwar Academic Publishers, The Netherlands, 2004.
[5]
Gunnar Asplund Kjell Eriksson and kjell Svensson, “DC Transmission based on
Voltage Source Converters, in Proc. of CIGRE SC14 Colloquium in
South Africa 1997.
