ABSTRACT:
This paper proposes a new type of converter called a
single-phase Z-source buck–boost matrix converter. The converter can buck and
boost with step-changed frequency, and both the frequency and the voltage can
be stepped up or stepped down. In addition, the converter employs a
safe-commutation strategy to conduct along a continuous current path, which
results in the elimination of voltage spikes on switches without the need for a
snubber circuit. The operating principles of the proposed single-phase Z-source
buck–boost matrix converter are described, and a circuit analysis is provided.
To verify the performance of the proposed converter, a laboratory prototype was
constructed with a voltage of 40 Vrms /60 Hz and a passive RL load. The
simulation and the experimental results verified that the converter can produce
an output voltage with three different frequencies 120, 60, and 30 Hz, and that
the amplitude of the output voltage can be bucked and boosted.
KEYWORDS:
1.
Buck–boost
voltage
2.
single-phase matrix converter
3.
step-up and
step-down frequency
4.
Z-source converter
SOFTWARE: MATLAB/SIMULINK
BLOCK
DIAGRAM:
Fig.1. General block diagram of the proposed topology
CONCLUSION:
In this paper, we have proposed a new single-phase
Z-source buck–boost matrix converter that can buck and boost to the desired
output voltage with step-changed frequency. The output of this single-phase
Z-source buck–boost matrix converter produces the voltage in buck–boost mode
with a step-changed frequency, in which the output frequency is either an
integer multiple or an integer fraction of the input frequency. It also provides
a continuous current path by using a commutation strategy. The use of this
safe-commutation strategy is a significant improvement as it makes it possible
to avoid voltage spikes on the switches without the use of a snubber circuit. We
presented a steady-state circuit analysis and described the operational stages.
To verify the performance of the proposed converter, we constructed a
laboratory prototype with an input voltage of 40 Vrms (57 Vpeak)/60 Hz based on
TMS320F2812 DSP, and we performed a PSIM simulation.
The simulation and the experimental results with a
passive RL load showed that the output voltage can be produced at three
different frequencies, 120, 60, and 30 Hz, and in the buck–boost amplitude mode.
Because of limitations in the power laboratory setup, the prototype was
intended only to verify the operational concept. We expect that this proposed
strategy can be used in various industrial applications that require
step-changed frequencies and variable voltage amplitudes. The proposed
converter is particularly suitable for controlling the speed of a fan or a pump
without the use of an inverter because for these applications, the input voltage
frequency must be changed to control their speed by stages.
REFERENCES:
[1] P. C. Loh, R. Rong, F. Blaabjerg, and
P.Wang, “Digital carrier modulation and sampling issues of matrix converters,” IEEE
Trans. Power Electron., vol. 24, no. 7, pp. 1690–1700, Jul. 2009.
[2]
Y. D. Yoon and S. K. Sul, “Carrier-based modulation technique for matrix converter,”
IEEE Trans. Power Electron., vol. 21, no. 6, pp. 1691–1703, Nov. 2006.
[3]
M. Jussila and H. Tuusa, “Comparison of simple control strategies of space-vector
modulated indirect matrix converter under distorted supply voltage,” IEEE
Trans. Power Electron., vol. 22, no. 1, pp. 139–148, Jan. 2007.
[4]
I. Sato, J. Itoh, H. Ohguchi, A. Odaka, and H. Mine, “An improvement method of
matrix converter drives under input voltage disturbances,” IEEE Trans.
Power Electron., vol. 22, no. 1, pp. 132–138, Jan. 2007.
[5]
C. Liu, B. Wu, N. R. Zargari, D. Xu, and J. Wang, “A novel threephase three-leg
ac/ac converter using nine IGBTs,” IEEE Trans. Power Electron.,
vol. 24, no. 5, pp. 1151–1160, May 2009.
