High-Gain Single-Stage Boosting Inverter for Photovoltaic Applications  

ABSTRACT:

This paper introduces a high-gain single-stage boosting inverter (SSBI) for alternative energy generation. As compared to the traditional two-stage approach, the SSBI has a simpler topology and a lower component count. One cycle control was employed to generate ac voltage output. This paper presents theoretical analysis, simulation and experimental results obtained from a 200 W prototype. The experimental results reveal that the proposed SSBI can achieve high dc input voltage boosting, good dc–ac power decoupling, good quality of ac output waveform, and good conversion efficiency

 KEYWORDS:

  1. Microinverter
  2. One cycle control (OCC)
  3. Tapped inductor (TI)

 SOFTWARE: MATLAB/SIMULINK

CIRCUIT DIAGRAM:

 Fig.1. Topology of the proposed SSBI

 EXPECTED SIMULATION RESULTS:

 Fig. 2. Simulated waveforms of the proposed SSBI on the line frequency scale.

Fig. 3. Simulated waveforms of the SSBI’s output voltage Vac , dc-link voltage Vdc , and dc input source current Ig with the TI operating at the CCM–DCM boundary (Po = Pob ).

Fig. 4. Simulated waveforms of the SSBI’s output voltage Vac , dc-link voltage Vdc , and dc input source current Ig : (a) illustrating the undistorted output voltage Vac , when SSBI is operated in deep DCM just above the minimum power level Po > Pomin and (b) illustrating the peak-shaving distortion of the output voltage Vac for Po < Pomin

 CONCLUSION:

A high-gain SSBI for alternative energy generation applications is presented in this paper. The proposed topology employs a TI to attain high-input voltage stepup and, consequently, allows operation from low dc input voltage. This paper presented principles of operation, theoretical analysis of continuous and discontinuous modes including gain and voltage and current stresses. To facilitate this report, two stand-alone prototypes one for 48 V input and another for 35 V input were built and experimentally tested. Theoretical findings stand in good agreement with simulation and experimental results. Acceptable efficiency was attained with low-voltage input source. The proposed SSBI topology has the advantage of high voltage stepup which can be further increased adjusting the TI turns ratio. The SSBI allows decoupled control functions. By adjusting the boost duty cycle Dbst, the SSBI can control the dc-link voltage, whereas the output waveform can be shaped by varying the buck duty cycleDbk. The ac–dc power decoupling is attained on the high-voltage dc link and therefore requires a relatively low capacitance value. The OCC control method was applied to shape the output voltage. OCC’s fast response and low sensitivity to dc-bus voltage ripple allowed applying yet smaller decoupling capacitor value, and has demonstrated low THD output for different types of highly nonlinear loads.

REFERENCES:

[1] S. B. Kjaer, J. K. Pedersen, and F. Blaabjerg, “A review of singlephase grid-connected inverters for photovoltaic modules,” IEEE Trans. Ind. Appl., vol. 41, no. 5, pp. 1292–1306, Sep. 2005.

[2] D. C. Martins and R. Demonti, “Interconnection of a photovoltaic panels array to a single-phase utility line from a static conversion system,” in Proc. IEEE Power Electron. Spec. Conf., 2000, pp. 1207–1211.

[3] Q. Li and P.Wolfs, “A current fed two-inductor boost converter with an integrated magnetic structure and passive lossless snubbers for photovoltaic module integrated converter applications,” IEEE Trans. Power Electron., vol. 22, no. 1, pp. 309–321, Jan. 2007.

[4] S. B. Kjaer, J. K. Pedersen, and F. Blaabjerg, “Power inverter topologies for photovoltaic modules—A review,” in Proc. Ind. Appl. Conf., 2002, vol. 2, pp. 782–788.

[5] C. Vartak, A. Abramovitz, and K. M. Smedley, “Analysis and design of energy regenerative snubber for transformer isolated converters,” IEEE Trans. Power Electron., vol. 29, no. 11, pp. 6030–6040, Nov. 2014.

High-Gain Single-Stage Boosting Inverter for Photovoltaic Applications

 

ABSTRACT

This paper introduces a high-gain single-stage boosting inverter (SSBI) for alternative energy generation. As compared to the traditional two-stage approach, the SSBI has a simpler topology and a lower component count. One cycle control was employed to generate ac voltage output. This paper presents theoretical analysis, simulation and experimental results obtained from a 200 W prototype. The experimental results reveal that the proposed SSBI can achieve high dc input voltage boosting, good dc–ac power decoupling, good quality of ac output waveform, and good conversion efficiency.

 

KEYWORDS

  1. Microinverter
  2. one cycle control (OCC)
  3. tapped inductor (TI)

 

SOFTWARE: MATLAB/SIMULINK

CIRCUIT DIAGRAM:

Fig.1. Topology of the proposed SSBI.

EXPECTED SIMULATION RESULTS

Fig. 2. Simulated waveforms of the proposed SSBI on the line frequency

scale.

Fig. 3. Simulated waveforms of the SSBI’s output voltage Vac , dc-link voltage Vdc , and dc input source current Ig with the TI operating at the CCM–DCM boundary (Po = Pob ).

Fig. 4. Simulated waveforms of the SSBI’s output voltage Vac , dc-link voltage Vdc , and dc input source current Ig : (a) illustrating the undistorted output voltage Vac , when SSBI is operated in deep DCM just above the minimum power level Po > Pomin and (b) illustrating the peak-shaving distortion of the output voltage Vac for Po < Pomin .

CONCLUSION

A high-gain SSBI for alternative energy generation applications is presented in this paper. The proposed topology employs a TI to attain high-input voltage stepup and, consequently, allows   operation from low dc input voltage. This paper presented principles of operation, theoretical analysis of continuous and discontinuous modes including gain and voltage and current stresses. To facilitate this report, two stand-alone prototypes one for 48 V input and another for 35 V input were built and experimentally tested. Theoretical findings stand in good agreement with simulation and experimental results. Acceptable efficiency was attained with low-voltage input source. The proposed SSBI topology has the advantage of high voltage stepup which can be further increased adjusting the TI turns ratio. The SSBI allows decoupled control functions. By adjusting the boost duty cycle Dbst, the SSBI can control the dc-link voltage, whereas the output waveform can be shaped by varying the buck duty cycleDbk. The ac–dc power decoupling is attained on the high-voltage dc link and therefore requires a relatively low capacitance value. The OCC control method was applied to shape the output voltage. OCC’s fast response and low sensitivity to dc-bus voltage ripple allowed applying yet smaller decoupling capacitor value, and has demonstrated low THD output for different types of highly nonlinear loads.

 

REFERENCES

[1] S. B. Kjaer, J. K. Pedersen, and F. Blaabjerg, “A review of singlephase grid-connected inverters for photovoltaic modules,” IEEE Trans. Ind. Appl., vol. 41, no. 5, pp. 1292–1306, Sep. 2005.

[2] D. C. Martins and R. Demonti, “Interconnection of a photovoltaic panels array to a single-phase utility line from a static conversion system,” in Proc. IEEE Power Electron. Spec. Conf., 2000, pp. 1207–1211.

[3] Q. Li and P.Wolfs, “A current fed two-inductor boost converter with an integrated magnetic structure and passive lossless snubbers for photovoltaic module integrated converter applications,” IEEE Trans. Power Electron., vol. 22, no. 1, pp. 309–321, Jan. 2007.

[4] S. B. Kjaer, J. K. Pedersen, and F. Blaabjerg, “Power inverter topologies for photovoltaic modules—A review,” in Proc. Ind. Appl. Conf., 2002, vol. 2, pp. 782–788.

[5] C. Vartak, A. Abramovitz, and K. M. Smedley, “Analysis and design of energy regenerative snubber for transformer isolated converters,” IEEE Trans. Power Electron., vol. 29, no. 11, pp. 6030–6040, Nov. 2014.

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 capability by using latest super convergence MOSFETs. In any case, these MOSFET-based inverter topologies encounter the evil impacts of no less than one of these drawbacks: MOSFET disillusionment danger from body diode pivot recovery, extended conduction incidents as a result of more devices, or low magnetics use. By part the conventional MOSFET based stage leg with a streamlined inductor, this paper proposes a novel MOSFET-based stage leg plan to restrict these burdens. In light of the proposed stage leg structure, a high viability single-arrange

MOSFET

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

 BLOCK DIAGRAM:

image001

Fig. 1. Two-stage nonisolated PV microinverter.

CIRCUIT DIAGRAM:

image002

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

 EXPERIMENTAL RESULTS:

image003

Fig. 3. Output voltage and current waveforms.

image004

Fig. 4. PWM gate signals waveforms.

image005

Fig. 5. Inverter splitting inductor current waveform.

image006

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 accomplishes:

1) high proficiency by utilizing super intersection MOSFETs and SiC diodes;

2) limited dangers from the MOSFET stage leg by part the MOSFET stage leg with streamlined inductor and limiting the di/dt from MOSFET body diode switch recuperation;

3) high magnetics use contrasted and past high proficiency 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 CMissue. A 250W hardware model has been planned, created, and tried in two-arrange nonisolated microinverter application. Exploratory outcomes exhibit that the proposed MOSFET transformerless inverter accomplishes 99.01% pinnacle effectiveness at full load condition and 98.8% CEC productivity and furthermore accomplishes around 98% attractive use. Because of the benefits of high effectiveness, low CM voltage, and enhanced attractive use, the proposed topology is alluring for two-organize nonisolated PV microinverter applications and transformerless string inverter applications.