Universidad Tecnol´ ogica de Pereira, Power Systems Laboratory B.S. Quintero & Y. S. Jimenez & G. Gonzalez 1 Report #8 Harmonics Analysis Brayan Steven Quintero Sierra, Yeison Stiven Jim´ enez Mej´ ıa & Gabriela Gonz´ alez Le´ on Electrical Power Systems Laboratory, Electrical Engineering Programme Universidad Tecnol´ ogica de Pereira Pereira, Colombia Group 3, Sub-group 4 brayanquintero6@utp.edu.co yeison.jimenez@utp.edu.co g.gonzalez@utp.edu.co Resumen—Debido a la presencia de cargas no lineales y la generaci´ on de arm´ onicos en los sistemas de transmisi´ on de energ´ ıa, se requiere realizar un exhaustivo an´ alisis de flujo de potencia arm´ onico. Este estudio tiene como objetivo principal determinar la ubicaci´ on ´ optima de filtros con el fin de mejorar la calidad de las se˜ nales de voltaje y corriente dentro del sistema de potencia. En este art´ ıculo, se lleva a cabo un estudio sobre los arm´ onicos presentes en los sistemas de transmisi´ on. Se comienza planteando un caso base que sirve como referencia, y a medida que se avanza en el estudio de flujo de potencia arm´ onico, se realizan modificaciones en el sistema. Adem´ as, se implementa la aplicaci´ on de filtros para mitigar los efectos indeseables de los arm´ onicos y mejorar la calidad de las se ˜ nales de voltaje y corriente. Todo el an´ alisis y las simulaciones se llevan a cabo utilizando el software PowerFactory, reconocido por su precisi´ on y capacidad para modelar sistemas de potencia complejos. Palabras clave—arm´ onicos, distorsi´ on arm´ onica, flujo de po- tencia, PowerFactory, sistema de potencia. Abstract—Due to the presence of nonlinear loads and the generation of harmonics in power transmission systems, a com- prehensive analysis of harmonic power flow is required. The primary objective of this study is to determine the optimal placement of filters in order to enhance the quality of voltage and current signals within the power system. In this article, a study of the harmonics present in transmission systems is conducted. It begins by establishing a baseline case as a reference, and as the study of harmonic power flow progresses, modifications are made to the system. Additionally, the implementation of filters is carried out to mitigate the undesirable effects of harmonics and improve the quality of voltage and current signals. All analyses and simulations are performed using the PowerFactory software, renowned for its accuracy and capability to model complex power systems. Keywords—harmonic distortion, harmonics, power flow, power system, PowerFactory. I. I NTRODUCTION T HE Power transmission systems play a vital role in ensuring the reliable and efficient supply of electricity to a wide range of industrial, commercial and residential applications. However, the presence of harmonics in voltage and current signals can significantly affect the performance and stability of these systems. Controlling harmonics and improving the quality of voltage and current signals have become critical objectives in the design and operation of power transmission networks [1]. This paper presents a study of power transmission systems with harmonics, starting with the implementation of a base case and subsequent modifications of the system to accom- modate additional elements, including an AC/DC converter to connect a DC motor. It also examines the use of filters as an effective solution for improving the quality of voltage and current signals. Through a technical analysis, this study aims to provide information on the challenges posed by harmonics and the benefits of filter-based approaches in power transmission systems. Firstly, the base case is used as a reference to analyse the impact of harmonics in power transmission. An analysis of the harmonic power flow is carried out, taking into account the effects of non-linear loads on the system. Non-linear loads such as rectifiers, electronic devices and converters introduce harmonics that distort voltage and current wave- forms. By quantifying the magnitude and frequency content of harmonics, electrical engineers can better understand the harmonic profile of the system and its potential consequences. Starting from the base case, the study introduces additional elements into the power transmission system, in particular an AC/DC converter connected to a DC motor. The inclusion of this converter represents a real scenario where power electronic devices are used for various applications, such as motor drives and renewable energy systems. This modification introduces new sources of harmonics and changes the system characteristics, requiring a thorough analysis of the resulting harmonic profiles, power losses and potential problems. To cope with the detrimental effects of harmonics, filters are used as a viable solution. Filters act as impedance devices that selectively attenuate specific frequency components, effec- tively reducing the harmonic content in the power system [2]. The use of filters allows the restoration of sinusoidal wave- forms, thus improving the quality and reliability of voltage and current signals. A thorough evaluation of system characteristics, such as the magnitude and frequency content of harmonics, guides the selection and placement of filters to ensure optimum harmonic suppression [3].