High-Efficiency MOSFET Transformerless Inverter for Non-isolated Microinverter Applications

ABSTRACT

Best in class low-control level metal– oxide– semiconductor field-affect transistor (MOSFET)- based transformerless photovoltaic (PV) inverters can achieve high capacity by using latest super union MOSFETs. In any case, these MOSFET-based inverter topologies encounter the suffering forcce of no less than one of these drawbacks:

MOSFET

MOSFET letdown danger from body diode pivot recovery, extended conduction event as a result of more devices, or low magnetics use. By part the conventional MOSFET based stage leg with a up to date inductor, this paper proposes a novel MOSFET-based stage leg plan to reduce these strain. In light of the proposed stage leg structure, a high viability single-arrange

PV

MOSFET transformerless inverter is shown for the PV microinverter applications. The pulsewidth change (PWM) direction and circuit undertaking rule are then describe. The ordinary mode and differential-mode voltage show is then displayed and consider for circuit structure. basic outcomes of a 250Whardware model are look to show the advantages of the proposed transformerless inverter on non-isolated two-sort out PV microinverter application.

 BLOCK DIAGRAM:

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Fig. 1. Two-stage nonisolated PV microinverter.

CIRCUIT DIAGRAM:

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Fig. 2. Proposed transformerless inverter topology with (a) separated magnetic and (b) integrated magnetics.

 EXPERIMENTAL RESULTS:

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Fig. 3. Output voltage and current waveforms.

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Fig. 4. PWM gate signals waveforms.

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Fig. 5. Inverter splitting inductor current waveform.

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Fig. 6. Waveforms of voltage between grid ground and DC ground (VEG ).

CONCLUSION

This paper proposes a MOSFET transformerless inverter with a novel MOSFET-based stage leg, which achieve:

1) high ability by apply super interchange MOSFETs and SiC diodes;

2) limited dangers from the MOSFET stage leg by part the MOSFET stage leg with up to date inductor and limiting the di/dt from MOSFET body diode switch recovery;

3) high magnetics use compare and past high ability MOSFET transformerless inverters in [21], [22], [25], which just have half magnetics use.

PWM

The proposed transformerless inverter has no dead-time necessity, basic PWM regulation for usage, and limited high-recurrence CM issue. A 250W hardware model has been planned, created, and tried in two-arrange non isolated micro inverter application. basic outcomes display that the proposed MOSFET transformerless inverter produce 99.01% height effectiveness at full load condition and 98.8% CEC capacity and furthermore produce around 98% attractive use. Because of the benefits of high strength, low CM voltage, and enhanced attractive use, the proposed topology is attractive for two-organize nonisolated PV microinverter applications and transformerless string inverter applications.