ABSTRACT:
This
paper develops an interesting converter for three phase grid interface for photovoltaic
panels. Here a new topology having least number of power semiconductor switches
in the five level category is used. The converter consists of three basic
sections viz. the photovoltaic source, a two phase inverter and a Scott-T
transformer that converts the two-phase inverter output to three phases and
connects to the grid. The control system is in the d-q reference frame which
provides fast dynamic control response. A maximum power point tracking
mechanism (MPPT) is used to generate the direct axis current reference in order
to inject the maximum available power into the grid for any insolation. The
converter has been designed and developed for 1kW. This is also experimentally
validated.
KEYWORDS:
1. Current
referenced control
2. Maximum
Power Point
3. Sine
pulse width modulation
4. Scott-T
Transformer
5. Isolated
Grid Tied Inverter
SOFTWARE:
MATLAB/SIMULINK
CONCLUSION:
The
paper presents a reduced switched method for generating a five level voltage
output from a PV system. The whole converter system consists of three stages,
the PV system with MPPT control, the 16 switch two-phase converter and finally
isolation stage using Scott-T transformer. The converter pumping the current
towards the grid is controlled by taking the PV MPP output current and
providing it as Id reference for the inverter. This Id reference current
controls the Id value of the inverter current control loop. Two-phase 16 switch
inverter topology consist of high frequency and low frequency stages. High
frequency stage will have a maximum switching stress voltage of Vdd=2 and
similarly low frequency unfolding stage will have a maximum stress voltage of
Vdd. The inverter has a self-balanced dc link capacitor pairs without any
complex control schemes. Proper simulation analysis for the five level inverter
sourced from a PV which in turn fed to grid has done which conforms its
application on grid tied applications. Hardware implementation for two-phase
level is also made and waveforms were verified comparing with the simulation. Further
section of hardware is to be done in future in order to detail verification and
making a complete prototype model for analysis.
REFERENCES:
[1]
B. Satish Naik , L. Umanand, K. Gopakumar and B. Subba Reddy, ”A New Two-Phase
Five-Level Converter for Three-Phase Isolated Grid-Tied Systems With Inherent
Capacitor Balancing and Reduced Component Count” IEEE Journal of Emerging and
Selected Topics in Power Electronics., VOL. 6, NO. 3,pp 1325-1335 Sep. 2018
[2]
Gautam A. Raiker, L. Umanand and B. Subba Reddy, ”Perturb and Observe with
Momentum Term applied to Current Referenced Boost Converter for PV Interface”
2018 IEEE International Conference on Power Electronics, Drives and Energy
Systems (PEDES)
[3]
Gautam A. Raiker , Subba Reddy B., Praveen C. Ramamurthy, L. Umanand, Abines S.
G. and Shama G. Vasisht ”Solar PV interface to Grid-Tie Inverter with Current
Referenced Boost Converter” 2018 IEEE 13th International Conference on
Industrial and Information Systems(ICIIS)
[4]
J. Rodrguez, J.-S. Lai, and F. Z. Peng, Multilevel inverters: A survey of topologies,
controls, and applications, IEEE Trans. Ind. Electron., vol. 49, no. 4, pp.
724738, Aug. 2002
[5]
A. Nabae, I. Takahashi, and H. Akagi, A new neutral-point-clamped PWM inverter,
IEEE Trans. Ind. Appl., vol. IA-17, no. 5, pp. 518523, Sep. 1981
