ABSTRACT:
This paper presents a
comparison of half bridge and full bridge isolated, soft-switched, DC-DC
converters for Electrolysis application. An electrolyser is a part of renewable
energy system which generates hydrogen from water electrolysis that used in
fuel cells. A DC-DC converter is required to couple electrolyser to system DC bus.
The proposed DC-DC converter is realized in both full-bridge and half-bridge
topology in order to achieve zero voltage switching for the power switches and
to regulate the output voltage. Switching losses are reduced by zero voltage
switching. Switching stresses are reduced by using resonant inductor and
capacitor. The proposed DC-DC converter has advantages like high power density,
low EMI, reduced switching stresses, high circuit efficiency and stable output voltage.
The MATLAB simulation results show that the output of converter is free from
the ripples and regulated output voltage and this type of converter can be used
for electrolyser application. Experimental results are obtained from a MOSFET
based DC-DC Converter with LC filter. The simulation results are verified with the
experimental results.
KEYWORDS:
1.
DC-DC
converter
2.
Electrolyser
3.
Renewable
energy sources
4.
Resonant
converter
5.
TDR
SOFTWARE: MATLAB/SIMULINK
CIRCUIT DIAGRAM:
Fig 1. Half Bridge DC-DC Converter.
Fig 2. Full Bridge DC-DC
Converter.
EXPECTED SIMULATION RESULTS:
Fig 3 (b) Driving Pulses
Fig 4 (c) Inverter output voltage with LC
filter
Fig 5 (d) Transformer secondary voltages
Fig 6 (e) Output voltage and current
Fig 7 (b) Driving Pulses
Fig 8 (c) Inverter output voltage with LC
filter
Fig 9 (d) Transformer secondary voltage
Fig 10 (e) Output voltage and current
CONCLUSION:
A
comparison of half bridge and full bridge isolated DC-DC converters for
Electrolysis application are presented. DC-DC converters for electrolyser
system is simulated and tested with LC filter at the output. The electrical
performances of the converter have been analyzed. The simulation and experimental
results indicate that the output of the inverter is nearly sinusoidal. The
output of rectifier is pure DC due to the presence of LC filter at the output.
Switching losses are reduced by zero voltage switching. Switching stresses are reduced
by using resonant inductor and capacitor The advantages of resonant converter
are reduced (di/dt), low switching losses and high efficiency. Switching losses
are reduced by zero voltage switching. Switching stresses are reduced by using
resonant inductor and capacitor The converter maximizes the efficiency through
the zero voltage switching and the use of super-junction MOSFET as switching
devices with high dynamic characteristics and low direct voltage drop. Half
bridge converter is found to be better than that of full bridge converter.
REFERENCES:
[1]
E.J.Miller, “Resonant switching power conversion,”in Power Electronics
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[2]
V. Volperian and S. Cuk , “A complete DC analysis of the series resonant
converter”, in IEEE power electronics specialists conf. Rec. 1982, pp. 85-100.
[3]
R.L. Steigerwald, “High-Frequency Resonant Transistor DC-DC Converters”, IEEE
Trans. On Industrial Electronics, vol.31, no.2, May1984, pp. 181-191.
[4]
D.J. Shortt, W.T. Michael, R.L. Avert, and R.E. Palma, “A 600 W four stage
phase-shifted parallel DC-DC converter,”, IEEE Power Electronics Specialists
Conf., 1985, pp. 136-143.
[5]
V. Nguyen, J. Dhayanchand, and P. Thollot, “A multiphase topology series-resonant
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