International Journal of Power Electronics and Drive System (IJPEDS) Vol. 11, No. 3, September 2020, pp. 1491~1498 ISSN: 2088-8694, DOI: 10.11591/ijpeds.v11.i3.pp1491-1498  1491 Journal homepage: http://ijpeds.iaescore.com Potency of PR controller for multiple harmonic compensation for a single-phase grid connected system D. Sattianadan 1 , Soumen Gorai 2 , G. R. Prudhvi Kumar 3 , S. Vidyasagar 4 , V. Shanmugasundaram 5 1,2,3,4 SRM Institute of Science and Technology, Kattankulathur, Chennai, Tamilnadu, India 5 Sona College of Technology, Salem, Tamilnadu, India Article Info ABSTRACT Article history: Received Oct 9, 2019 Revised Feb 29, 2020 Accepted Mar 18, 2020 Harmonics and grid synchronization are one of the major problems faced when dealing with a single-phase system. The development of technology in the PV system makes the consumer to use it in a wide range. The power transferred from PV to grid needs DC to AC conversion process which is done by static devices operating with the higher frequencies that causes the harmonics in the grid connected system. The main aim of the paper is to implement grid synchronization and reduce total harmonic distortion in a single-phase grid connected system. The design of LCL filter is addressed in this paper which depends on current ripple, filter size and switching ripple attenuation. In order to account the harmonic content, the FFT analysis is made both in analysis and Matlab Simulink. The Proportional Resonant (PR) controller is developed and work along with LCL filter for reducing the harmonic content. The stability of the system with PR is analyzed using root locus and bode plots and results are compared with PI controls. The result shows that PR controller performs better compared to the PI controller for reducing the harmonic content present in the single-phase system and for improving the system stability. Keywords: Fast fourier transform (FFT) Grid synchronisation Phase locked loop (PLL) Proportional resonant (PR) controller Total harmonics distortion (THD) This is an open access article under the CC BY-SA license. Corresponding Author: D. Sattianadan, Departement of Electrical and Electronics Engineering, SRM Institute of Science and Technology, Chennai. Email: sattia.nadan@gmail.com 1. INTRODUCTION In the recent energy trends, there is a tremendous increase in the demand for renewable energy. Solar being the most abundant source, Photovoltaic systems can be used as a replacement for conventional energy sources. To Study the characteristics and to adjust the parameters of PV system, it must be modelled properly before connecting to the network. The author presents a method to model a solar cell using equivalent circuit of solar cell. This model for PV system has been developed based on a mathematical equation that shows the variation of output of the solar cell with varying temperature, irradiation, series resistance and shunt resistance [1-3]. The major disadvantage of solar energy is the low usable energy as the output, which can be overcome by using a Maximum Power Point Tracking (MPPT) technique. Many MPPT techniques has been developed in the recent years among which the most commonly used MPPT technique is Perturb and Observe method because of its ease for implementation [4-6]. The ANN based controllers with HILL climbing algorithm reaches the maximum power point in a fast manner and increase the output of the PV. Based on the values of solar insolation and temperature, the output of reference voltage has been determined by ANN and the output of the controller is further optimized by HILL climbing algorithm [7]. The development of modern controllers increases the output of PV system effectively