ABSTRACT
A multilevel boost PFC (Power Factor Correction) rectifier is presented
in this paper controlled by cascaded controller and multicarrier pulse width modulation
technique. The presented topology has less active semiconductor switches
compared to similar ones reducing switching losses as well as the number of required
gate drives that would shrink manufactured box significantly. A simple
controller has been implemented on the studied converter to generate a constant
voltage at the output while generating a five-level voltage waveform at the
input without connecting the load to the neutral point of the DC bus
capacitors. Multicarrier PWM technique has been used to produce switching
pulses from control signal. Multi-level voltage waveform harmonics has been analyzed
comprehensively which affects the size of input current and required filters
directly. Full simulation and experimental results confirm the good dynamic performance
of the proposed five-level PFC boost rectifier in delivering power from AC grid
to the DC loads while correcting the power factor at the AC side as well as reducing
the current harmonics remarkably.
KEYWORDS
1.
Multilevel
Converter
2.
Active Rectifier
3.
Multicarrier PWM
4.
Cascaded Control
5.
Power Quality
SOFTWARE: MATLAB/SIMULINK
CONCLUSION
In this paper a reduced switch count
5-level boost PFC rectifier has been presented. A cascaded PI controller has
been designed to regulate the output DC voltage and to ensure the unity power
factor mode of the input AC voltage and current. Moreover, low harmonic AC
current waveform has been achieved by the implemented controller and employing
a small inductive filter at the input line. One of the main issues of switching
rectifiers is the high switching frequency that has been reduced in this work
using PWM technique through adopting multicarrier modulation scheme. Moreover,
DC capacitors middle point has not been connected to the load that had required
splitting the load to provide a neutral point. Using a single load with no
neutral point makes this topology practical in realistic applications.
Comprehensive simulations cases including change in the load, AC voltage
fluctuation and generating different DC voltage values have been analysed and
performed to ensure the good dynamic performance of the rectifier, adopted
controller and switching technique.
REFERENCES
[1] B. Singh, B. N. Singh, A. Chandra, K.
Al-Haddad, A. Pandey, and D. P. Kothari, "A review of single-phase improved
power quality ACDC converters," Industrial Electronics, IEEE
Transactions on, vol. 50, pp. 962-981, 2003.
[2] B. Singh, B. N. Singh, A. Chandra, K.
Al-Haddad, A. Pandey, and D. P. Kothari, "A review of three-phase improved
power quality AC-DC converters," Industrial Electronics, IEEE
Transactions on, vol. 51, pp. 641-660, 2004.
[3] H. Abu-Rub, J. Holtz, J. Rodriguez,
and G. Baoming, "Mediumvoltage multilevel converters—State of the art,
challenges, and requirements in industrial applications," IEEE Trans.
Ind. Electron., vol. 57, pp. 2581-2596, 2010.
[4] H. Abu-Rub, M. Malinowski, and K.
Al-Haddad, Power electronics for renewable energy systems, transportation
and industrial applications: John Wiley & Sons, 2014.
[5] L. Yacoubi, K. Al-Haddad, L.-A. Dessaint,
and F. Fnaiech, "A DSPbased implementation of a nonlinear model reference
adaptive control for a three-phase three-level NPC boost rectifier
prototype," Power Electronics, IEEE Transactions on, vol. 20, pp.
1084-1092,
2005.
