Design and Implementation of a Robust Current Controller for Single-Phase Inverters Connected Electrical Network via a damped LCL filter for Renewable Energy Systems

J. A. Borges, M. V. B. Mendonça, F. A. M. Moura, M. R. M. C. Albertini



A renewable energy source plays an important role in electricity generation. Various renewable energy sources like wind, solar, geothermal, ocean thermal, and biomass can be used for generation of electricity and for meeting our daily energy needs. Energy from the sun is the best option for electricity generation as it is available everywhere and is free to harness. This paper deals with the design and implementation of a current controller for a single-phase voltage-fed inverter connected via an LCL filter. In this proposal, a single-phase micro-inverter connected to the power grid based on a complete bridge topology and the effects presented by the inclusion of a notch filter in the external voltage control mesh were analyzed. The proposed control improves the harmonic rejection capacity of the single phase inverters connected to the electric grid for application in photovoltaic panels, which is based on an alternative control structure and the proper selection of the LCL filter feedback current. The inclusion of a high order filter such as LCL in place of the traditional inductive filter provided greater capacity and attenuation of the unwanted components. However, the resonance from this filter impairs the stability of the system, requiring the inclusion of passive or active damping techniques. With the notch filter acting on the system, the current injected into the network had a substantially better total harmonic distortion index (THD), mainly due to the elimination of the 120 Hz ripple, meeting the requirements of international standards such as IEEE 1547.
In addition, the control of the system proved to be robust and efficient, keeping the steady state error close to zero even in the event of voltage sinking and variations in the frequency of the network.

Published in: Renewable Energy & Power Quality Journal (RE&PQJ, Nº. 16)
Pages: 209-214 Date of Publication: 2018/04/20
ISSN: 2172-038X Date of Current Version:2018/03/23
REF: 263-18 Issue Date: April 2018
DOI:10.24084/repqj16.263 Publisher: EA4EPQ

Authors and affiliations

J. A. Borges(1), M. V. B. Mendonça(2) , F. A. M. Moura(2), M. R. M. C. Albertini(2)
1. Universidade Federal de Uberlandia, Electrical Engineering Department Uberlandia- Minas Gerais, Brazil,
2. Universidade Federal do Triângulo Mineiro, Electrical Engineering Department, Uberaba- Minas Gerais, Brazil

Key words

Electric power. Harmonic distortion. Imbalance. Quality electricity. Renewable energies. photovoltaic system.


[1] AL-MASRI, Hussein M.; EHSANI, Mehrdad. Feasibility investigation of a hybrid on-grid wind photovoltaic retrofitting system. IEEE Transactions on Industry Applications, v. 52, n. 3, p. 1979-1988, 2016.
[2] TEODORESCU, Remus et al. Grid converters for photovoltaic and wind power systems. John Wiley & Sons, 2011.
[3] MAGHAMI, Mohammadreza; HIZAM, Hashim; GOMES, Chandima. Impact of dust on solar energy generation based on actual performance. In: Power and Energy (PECon), 2014 IEEE International Conference on. IEEE, 2014. p. 388- 393.
[4] GARRAOUI, Radhia; HAMED, Mouna Ben; SBITA, Lassaad. Comparison of MPPT algorithms for DC-DC Boost converters based PV systems using robust control technique and artificial intelligence algorithm. In: Systems, Signals & Devices (SSD), 2015 12th International Multi-Conference on. IEEE, 2015. p. 1-6.
[5] MOHAMMED, S. Sheik; DEVARAJ, D. Simulation of incremental conductance MPPT based two phase interleaved Boost converter using MATLAB/simulink. In: Electrical, Computer and Communication Technologies (ICECCT), 2015 IEEE International Conference on. IEEE, 2015. p. 1-6.
[6] HU, Boyang; SATHIAKUMAR, Swamidoss. Current ripple cancellation of multiple paralleled Boost converters for pv/battery charging system with mppt. In: Innovative Smart Grid Technologies Asia (ISGT), 2011 IEEE PES. IEEE, 2011. p. 1-6.
[7] BARBI, Ivo. Modelagem de conversores CC-CC. Florianópolis: Edição do autor, 2015.
[8] Yepes, A.G., Digital Resonant Current Controllers for Voltage Source Converters, Doctoral Dissertation, University of Vigo, 2011.
[9] Aleksandr Reznik, Marcelo Godoy Simoes, Ahmed Al-Durra, LCL Filter Design and Performance Analysis for Grid-Interconnected Systems,IEEE Transactions on Industry Applications,Vol.50, N.2,March-April,2014, pp1225-1232.
[10] Daniel Nahum Zmood and Donald Grahame Holmes,Stationary Frame Current Regulation of PWM InvertersWith Zero Steady-State Error, IEEE Transations On Power Electronics, Vol. 18, No. 3, May 2003, pp814-822.
[11] R. Teodorescu, F. Blaabjerg, M. Liserre and P.C. Loh, Proportional-resonant controllers and filters for grid-connected voltage-source converters, IEE Proc.-Electr. Power Appl., Vol. 153, No. 5, September , 2006
[12] Alon Kuperman, Proportional-Resonant Current Controllers Design Based on DesiredTransient Performance, IEEE Transations On Power Electronics, Vol. 30, No. 10, October 2015, pp5341-5345.
[13] S. J. M. Machado. “Uma proposta de controle com alta capacidade de rejeição harmônica para inversores monofásicos conectados à rede elétrica através de filtro LCL amortecido para sistemas de energia renovável”. Dissertação de mestrado apresentado na UEL, Londrina/PR, 2016.