An Improved Seven-Level PUC InverterTopology with Voltage Boosting

 ABSTRACT:

 In this brief, a seven-level (7L) improved packed U cell (IPUC) inverter with reduced power electronic components is proposed. The presented IPUC inverter has low voltage stress on switches and is capable of voltage boosting. A new voltage balancing method based on logic form equations is developed for regulating the inherent floating capacitor voltage to half the input DC voltage. The proposed 7L IPUC is compared with other state-of-the-art 7L inverters in terms of number of IGBTs, blocking voltage and driver circuits for attesting its superior merits. The performance of the proposed voltage balancing is verified through a laboratory prototyped 7L IPUC inverter considering varying load conditions and the corresponding results are elucidated.

KEYWORDS:

1.      Logic form equations

2.       Multilevel inverters,

3.      Voltage balancing

4.      Voltage boosting

SOFTWARE: MATLAB/SIMULINK

CONCLUSION:

A 7L IPUC inverter topology with reduced power electronics components like switching devices, driver circuits and passive components was presented. The inherent floating capacitor voltage was balanced by using the logic form equations which is independent to the load power factor and its suitable dynamic load variation. The boosting ability of the proposed topology was verified through several experimental tests and the results were presented. Finally, the proposed inverter was benchmarked in terms of number of components against its counterpart topologies. Also, the detailed cost analysis revealed the cost effectiveness of the developed topology. With these attributes, it qualifies as a challenging candidate for medium voltage grid connected photovoltaic system and electric vehicle applications.

REFERENCES:

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