ABSTRACT:
Presently Multilevel inverters are extensively used
for high-voltage applications and their execution is exceptionally better to
that of regular two-level inverters due to minimized harmonic distortion, lower
electromagnetic interference and larger DC link voltages. Nevertheless certain
shortcomings are faced such as adding in number of components and voltage balancing
problem. In order to overcome these, a seven-level hybrid inverter has been
proposed. This topology requires a lesser number of power switches which
results in the decrease of multifaceted nature, add up to cost and weight of
the inverter. Finally this can be able to generate near sinusoidal voltages and
approximately fundamental frequency switching. The simulation and the
experimental results of a modified cascaded seven level H bridge inverter with
and without LC filter are presented for validation.
KEYWORDS:
1.
Cascaded H-bridge inverter (CHBI)
2.
Seven level hybrid inverter
3.
Asymmetrical DC sources
4.
Total harmonic distortion (THD)
5.
Pulse Width modulation (PWM)
6.
Multi-level Inverter
SOFTWARE:
MATLAB/SIMULINK
CONCLUSION:
A
modified cascaded seven level H-bridge inverter was fabricated which has the
benefit of reduced THD, portability, and cost has compared to normal cascaded
H-bridge inverter. Since the topology requires minimum switches, and low-cost real
time interfacing device (Arduino) compared DSP, DSPACE, FPGA, etc., the overall
expenditure for fabrication reduces. This paper envisages the working of
proposed structure. An LC filter is introduced which helps in getting nearer to
sinusoidal waveform. The concepts which are projected are verified through
simulation and experimental results.
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