International Journal of Electrical and Computer Engineering (IJECE) Vol. 14, No. 5, October 2024, pp. 4888~4896 ISSN: 2088-8708, DOI: 10.11591/ijece.v14i5.pp4888-4896  4888 Journal homepage: http://ijece.iaescore.com Assessing power quality in individual circuits of industrial electrical system Eliana Noriega Angarita 1 , Vladimir Sousa Santos 1 , Pablo Daniel Donolo 2 , Enrique Ciro Quispe 3 1 Energy Department, Faculty of Engineering, Universidad de la Costa, Barranquilla, Colombia 2 Departament of Electricity and Electronics, Faculty of Engineering, Universidad Nacional de Rio Cuarto, Rio Cuarto, Argentina 3 GIEN Research Group, Faculty of Engineering, Universidad Autonoma de Occidente, Cali, Colombia Article Info ABSTRACT Article history: Received Mar 8, 2024 Revised Jul 4, 2024 Accepted Jul 9, 2024 This article evaluates energy quality in individual circuits within an industrial electrical system and its impact on common connection point parameters. The research is crucial due to rising challenges in power quality arising from increased nonlinear electrical loads in industrial processes. The study involves sequential steps, covering the industrial electrical system´s description, power quality parameters analysis, and issue identification. A comprehensive assessment was conducted on a 3,000 kVA, 13.8 kV/460 V point of common coupling (PCC) transformer, and 10 transformers (10 to 250 kVA) supplying individual circuits. Findings indicated load factors below 70% in all transformers and a power factor below 0.9 in eight. Issues like voltage variation, current imbalance, and harmonic distortion were identified in nine transformers supplying individual circuits, while the PCC exhibited no power quality problems. The research emphasizes the importance of including individual circuits in power quality assessments, as compliance with regulatory limits at the PCC may not guarantee the absence of power quality issues in individual circuits, affecting equipment lifespan and increasing energy losses. Keywords: Harmonic analysis Individual circuits Industrial system diagnosis Power quality measurements Standard application This is an open access article under the CC BY-SA license. Corresponding Author: Eliana Noriega Angarita Energy Department, Faculty of Engineering, Universidad de la Costa Calle 58 No. 55-66, Barranquilla, Colombia Email: enoriega2@cuc.edu.co 1. INTRODUCTION Maintaining electrical power quality is crucial for equipment, preventing disruptions in voltage and current waveforms [1], [2]. Deviations in electromagnetic parameters can lead to faults or improper operation, causing energy and economic losses in both the power electrical system (SEP) and industrial electrical system (IES) [3], [4]. The industrial sector, a significant energy consumer, increasingly relies on electronic equipment, causing non-linear behavior and power quality issues within the IES [5]–[8]. Literature highlights studies characterizing power quality in the industrial sector, revealing prevalent issues such as voltage variations, unbalances, and distortions [9]–[14]. In study [9], harmonic disturbances in the cement industry are assessed through measurements of electromagnetic parameters, revealing voltage and current harmonics caused by non-linear loads. In study [10], it focuses on power quality in the granite slab manufacturing industry, comparing electromagnetic data with international standards and highlighting voltage harmonic issues due to non-linear loads. In study [11], MATLAB ® simulation results on an IES in a steel plant show that nonlinear load characteristics generate harmonic currents and flickers. In study [12], it explores power quality in an oil processing plant, emphasizing voltage harmonics' impact on the supply network. The results demonstrate that the nonlinear