RESEARCH ARTICLE Power quality improvement in grid integrated solar water pumping system using Vienna converter Shadab Murshid | Bhim Singh Department of Electrical Engineering, Indian Institute of Technology Delhi, New Delhi, India Correspondence Shadab Murshid, Department of Electrical Engineering, Indian Institute of Technology Delhi, New Delhi, India. Email: mail2smurshid@gmail.com; shadab.murshid@ee.iitd.ac.in Funding information UKICERI, Grant/Award Number: RP03391; JC Bose fellowship, Grant/ Award Number: RP03128 Summary A new topology for solar water pumping (SWP) using a permanent magnet synchronous motor drive is proposed in this work. With the aim of overcoming the intermittency issues of solar photovoltaic (PV) generation, the utility grid is introduced in order to provide a reliable water pumping operation. The grid interface is facilitated using a Vienna rectifier, which enables the rated opera- tion of the pump. The Vienna rectifier maintains the direct current (DC) link voltage, removes the grid current harmonics, and ensures unity power factor at the grid. A novel multi‐resonant second‐order generalized integrator frequency‐locked loop (FLL)–based approach is proposed for extraction of fun- damental positive sequence components from the grid voltages. The novelty of the proposed control approach lies in the elimination of dominant lower order harmonics from the sensed grid voltages through selective harmonic elimina- tion. The FLL structure makes the control structure flexible to grid frequency change within small range. The optimum power point of solar PV array is extracted using an incremental conductance scheme. A sensorless field‐ oriented control is used for regulating the pump speed. The system ) performance is observed under different operating conditions on a laboratory developed prototype. Test results confirm the satisfactory performance and improved power quality indices fulfilling the IEEE‐519 standard. KEYWORDS frequency‐locked loop, permanent magnet synchronous motor, power quality, solar water pumping, utility grid 1 | INTRODUCTION The escalating energy needs and exhausting reserves of conventional energy sources have emerged as one of the greatest challenge for the mankind. Therefore, alternate energy sources, which are everlasting, need to be explored to cope up with the prevailing energy crisis. Numerous renewable energy sources have established themselves as a reliable source to support the increasing demand. However, for areas receiving healthy solar insolation for most of the part of a year, solar photovoltaic (PV) generation remains invincible. 1 With greater effort being laid on increasing the solar cell effi- ciency, Kaneka Cooperation has developed a practical solar cell with highest efficiency 2 of 26%. A considerable reduc- tion in size of solar PV array is expected with the use of increased efficiency solar cells. The widespread use of solar PV array is resulting in falling price of the PV modules such that a sharp decline in cost of solar PV array of about 60% has been realized over a decade. The prices are further expected to fall in the coming years. 3 Among the number of Received: 17 December 2018 Revised: 7 May 2019 Accepted: 16 May 2019 DOI: 10.1002/2050-7038.12129 Int Trans Electr Energ Syst. 2019;e12129. https://doi.org/10.1002/2050-7038.12129 © 2019 John Wiley & Sons, Ltd. wileyonlinelibrary.com/journal/etep 1 of 20