Citation: Ali, M.B.; Kazmi, S.A.A.; Khan, Z.A.; Altamimi, A.; Alghassab, M.A.; Alojaiman, B. Voltage Profile Improvement by Integrating Renewable Resources with Utility Grid. Energies 2022, 15, 8561. https://doi.org/10.3390/en15228561 Academic Editor: Abu-Siada Ahmed Received: 6 October 2022 Accepted: 10 November 2022 Published: 16 November 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). energies Article Voltage Profile Improvement by Integrating Renewable Resources with Utility Grid Muhammad Bilal Ali 1 , Syed Ali Abbas Kazmi 1 , Zafar A. Khan 2, * , Abdullah Altamimi 3,4 , Mohammed A. Alghassab 5 and Bader Alojaiman 6, * 1 U.S.-Pakistan Center for Advanced Studies in Energy (USPCAS-E), National University of Sciences and Technology (NUST), Islamabad 44000, Pakistan 2 Department of Electrical Engineering, Mirpur University of Science and Technology, Mirpur A.K.10250, Pakistan 3 Department of Electrical Engineering, College of Engineering, Majmaah University, Al-Majmaah 11952, Saudi Arabia 4 Engineering and Applied Science Research Center, Majmaah University, Al-Majmaah 11952, Saudi Arabia 5 Department of Electrical and Computer Engineering, Shaqra University, Riyadh 11911, Saudi Arabia 6 Department of Computer Science, Community College, Shaqra University, Shaqra 11961, Saudi Arabia * Correspondence: zafarakhan@ieee.org (Z.A.K.); alojaiman@su.edu.sa (B.A.) Abstract: There are three main parts of an electric power system—power generation, transmission, and distribution. For electric companies, it is a tough challenge to reduce losses of the power system and deliver lossless and reliable power from the generating station to the consumer end. Nowadays, modern power systems are more complex due to gradually increasing loads. In the electrical power system, especially in transmission and distribution networks, there are power losses due to many reasons such as overloading of the line, long distribution lines, low power factors, corona losses, and unsuitable conductor size. The main performance factor of the power system is reliability. Reliability means continuity of the power supply without any interruptions from the generating station to the demand side. Thus, due to these power losses, there are voltage stability problems and economic losses in the electrical system. The voltage stability of the power system can be increased by improving the voltage profile. In this paper, different techniques are analyzed that include the integration of wind power, the integration of photovoltaic power, and reactive power injection by integrating FACTS devices. These techniques are applied to the IEEE 57 bus system with standard data using simulation models developed in MATLAB. Thus, the results of the analysis of these techniques have been compared with each other. Keywords: voltage stability; wind energy; photovoltaic energy; STATCOM; PSAT 1. Introduction Power generation, distribution, and transmission are the three main parts of the electric power system. It is quite challenging for electric companies to reduce losses in the electrical power system and deliver lossless and reliable power from the generating side to the consumer side [1]. Nowadays, the modern power system is more complex due to the everyday increase in load. The main factor of the power system is reliability. Reliability means continuity of the supply (power supply) without any interruption from the generating station to the demand side. Thus, power is delivered with the help of the transmission and distribution system, and losses of transmission and distribution systems are reduced to increase system reliability. In the transmission system, there is a major loss called corona loss due to the flow of power on the conductor’s surface. Thus, corona loss is reduced by using a bundle of conductors. The transmission system starts after the generating station and ends at the feeder. However, the distribution system begins from the feeder to the consumer end. The primary distribution system initiates from the feeder and Energies 2022, 15, 8561. https://doi.org/10.3390/en15228561 https://www.mdpi.com/journal/energies