Download Precision DC-to-AC power conversion by optimization

SINGLE INDUCTOR DUAL BUCK FULL-BRIDGE INVERTER
ABSTRACT:
A new single inductor dual buck full-bridge inverter is proposed in this
paper. The inverter is improved on the basis of a dual buck inverter, and it retains
the advantage of a no reverse recovery of body diode. The dc voltage utilization
rate can be increased by adopting the voltage commutation bridge instead of the
voltage-dividing capacitors in the inverter. In addition, comparing with other dual
buck inverters, the inverter has just one filter inductor, which can make the volume
and weight of the system decreased observably and improve the integration. The
controlling method, combining the high- and low-frequency modulation, is adopted
to weaken the complexity of control and improve the reliability and stability of the
system. The operating principle, characteristic analysis, simulation and experiment
are provided in this paper. A 1-kW prototype is established and tested, and the
results of simulation and experiment verify the correctness of the theoretical
analysis.
INTRODUCTION:
The shoot-through problem is a major killer of the reliability. It needs to set dead
time to avoid the problem, but the dead-time effect will cause the distortion of
output. During the dead time, the inductor current flows through the body diode,
which has long reverse recovery time and great loss.
Therefore, except for the bridge-type inverter, the dual-buck type inverter is
proposed along with lots of research and development in recent years. The basic
unit of dual-buck-type inverter is unidirectional buck circuit;
thus, there is no shoot-through problem in the inverter and the freewheeling
current flows through the independent diodes instead of body diodes of the
switches, which is conducive to reducing the reverse recovery loss, increasing the
switching frequency and using the super-junction power metal–oxide–v-semiconductor field-effect transistor with low on-resistance. In addition, it is easy to
have the series and parallel combinations for the inverter and construct a threephase system.
Therefore, except for the bridge-type inverter, the dual-buck type inverter is
proposed along with lots of research and development in recent years. The basic
unit of dual-buck-type inverter is unidirectional buck circuit; thus, there is no shoot
through problem in the inverter and the freewheeling current flows through the
independent diodes instead of body diodes of the switches, which is conducive to
reducing the reverse recovery loss, increasing the switching frequency and using
the super-junction power metal–oxide–semiconductor field effect transistor with
low on-resistance.
In addition, it is easy to have the series and parallel combinations for the inverter
and construct a three-phase system. The rudiment of a dual buck inverter was
proposed used it for the high-frequency power amplifier treated this circuit as the
CII inverter, which was used to the three phase system to get the interleaved ripple
current of two buck bridge legs.
EXISTING SYSTEM:
The DBHBI without circulation current was introduced, which contributed
to realizing high reliability, high frequency, and high efficiency. The half-bridge
input mode, which leads to a low input-voltage utilization rate and high voltage
stress
PROPOSED SYSTEM:
This paper proposed a new single inductor dual buck full-bridge inverter,
which works without circulation current and adopts sinusoidal pulse width
modulation (SPWM) control method. The schematic of SIDBFBI proposed, which
consists of voltage commutation bridge and bidirectional current-mode highfrequency chopper circuit. The voltage commutation bridge works at low
frequency, just changing the polarity of the input voltage Ui, and the output voltage
uA is power-frequency square wave. Then, the bidirectional current mode highfrequency chopper circuit with no shoot-through problem carries out the highfrequency chopping for uA, outputting single polar high-frequency modulation
wave uC, which is changed into the output voltage uo by filtering
ADVANTAGES:
 It retains the advantages of a dual buck inverter as follows: high conversion
efficiency, no reverse recovery of body diode. In addition, the switches of
the commutation bridge work at power frequency; thus, the effect of shootthrough problem can be ignored.
 Compared with other dual buck inverters, the inverter has only one filter
inductor; thus, the volume and weight of the system are observably
decreased, and the integration is more improved.
 Compared with the half-bridge style inverter, the voltage dividing capacitor
is not needed at the dc side, and the voltage stress of power devices can be
reduced at the same output voltage, which is suitable for the high-voltage
and high-power occasions
BLOCK DIAGRAM:
TOOLS AND SOFTWARE USED:
 MPLAB – microcontroller programming.
 ORCAD – circuit layout.
 MATLAB/Simulink – Simulation
APPLICATIONS:
 Aerospace.
 New energy power generation.
 Smart power grids.
 High voltage and high- power converting fields.
CONCLUSION:
This paper has proposed a new single inductor dual buck full-bridge
inverter, analyzing the particular working process of the inverter and verifying the
process by simulation and experiment. From the theoretical analysis and
experimental result of the prototype, it is obtained that the proposed inverter has
the following advantages. 1) It retains the advantages of a dual buck inverter as
follows: high conversion efficiency, no reverse recovery of body diode. In
addition, the switches of the commutation bridge work at power frequency; thus,
the effect of shoot through problem can be ignored. 2) Compared with other dual
buck inverters, the inverter hasnonly one filter inductor; thus, the volume and
weight of the system are observably decreased, and the integrationnis more
improved. 3) Compared with the half-bridge style inverter, the voltage dividing
capacitor is not needed at the dc side, and the voltage stress of power devices can
be reduced at the same output voltage, which is suitable for the high-voltage and
high-power occasions. 4) The proposed can be used as a grid-connected inverter,
and the leakage current is restrained and meets the safety standard. 5) The structure
and control of the inverter are simple, and easy to be realized. The inverter is
suitable for the occasion requiring high reliability, high conversion efficiency,
small volume and weight.
REFERENCES:
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current regulated DC/AC converter module,” in Conf. Rec. IEEE IAS Annu.
Meet., 1995, pp. 929–934.
[3] G. R. Stanley and K. M. Bradshaw, “Precision DC-to-AC power conversion by
optimization of the output current waveform-the half bridge revisited,” IEEE
Trans. Power Electron., vol. 14, no. 2, pp. 372–380, Mar. 1999.
[4] A. M. Knight, J. Ewanchuk, and J. C. Salmon, “Coupled three-phase inductors
for interleaved inverter switching,” IEEE Trans. Magn., vol. 44, no. 11, pp. 4119–
4122, Nov. 2008.