Design of Cascaded Modular Multilevel Converter for Grid Connected PV System

International Journal of Electrical and Electronics Engineering |

© 2019 by SSRG - IJEEE Journal |

Volume 6 Issue 4 |

Year of Publication : 2019 |

Authors : Tetali Swathi, V S N Narasimha Raju, K Sainadh Singh, G.Srinivas Reddy |

: 10.14445/23488379/IJEEE-V6I4P103 |

##### Citation:

Tetali Swathi, V S N Narasimha Raju, K Sainadh Singh, G.Srinivas Reddy, *"Design of Cascaded Modular Multilevel Converter for Grid Connected PV System"* SSRG International Journal of Electrical and Electronics Engineering 6.4 (2019): 13-21.

Tetali Swathi, V S N Narasimha Raju, K Sainadh Singh, G.Srinivas Reddy,(2019). Design of Cascaded Modular Multilevel Converter for Grid Connected PV System. *SSRG International Journal of Electrical and Electronics Engineering* 6(4), 13-21.

##### Abstract:

Today renewable energy sources are becoming more popular with ever increasing energy demand and environmental pollution due to non-renewable energy sources. Among the renewable energy sources, major portion of energy is generated using Photovoltaic system. Grid connected photovoltaic systems are gaining more importance. Large-scale grid connected PV systems can be easily and effectively interfaced with the modular multilevel converters when compared with conventional DC-DC converters. As modular multilevel converters have unique advantages like enhanced energy harvesting capability, scalability etc. they can be used for many applications such as STATCOM, harmonic compensator and so on. PV systems face tough challenges such as output voltage over modulation and power flow control due to irregular output voltages from PV arrays. This paper proposes a decoupled active and reactive power control method to improve the system performance. A 3-MW, 12kV PV system with the proposed control strategy is modelled and the results are verified using MATLAB simulation.

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##### Key Words:

Multilevel converters, decoupled active and reactive power control, photovoltaic systems.