International Journal of Power Electronics and Drive Systems (IJPEDS) Vol. 13, No. 3, September 2022, pp. 1625~1634 ISSN: 2088-8694, DOI: 10.11591/ijpeds.v13.i3.pp1625-1634  1625 Journal homepage: http://ijpeds.iaescore.com Developing a hybrid filter structure and a control algorithm for hybrid power supply Yuriy Anatolievich Sychev, Maxim Evgenievich Aladin, Serikov Vladimir Aleksandrovich Department of Power Engineering and Electromechanics, Saint-Petersburg Mining University, Saint Petersburg, Russian Federation Article Info ABSTRACT Article history: Received Dec 9, 2021 Revised May 27, 2022 Accepted Jun 11, 2022 The paper presents the results of a study on hybrid filter operation and performance under hybrid power supply. In the study, a hybrid filter structure was developed and proved to perform a set of power quality improving functions. The paper demonstrates that it is necessary for the hybrid filter structure to be variable in order to adapt to changes in power supply. A case is made for using an additional passive filter at the active part output of the hybrid filter under distributed generation. The optimal structure and parameters of such an additional passive filter are identified and proved. Based on the experimental research results, the mathematical and computer simulation models of the proposed hybrid filter for hybrid power supply were developed. The modeling and simulation results showed the efficiency level to be satisfactory and power quality to improve due to applying the proposed hybrid filter. Using the modeling and simulation results, an adaptive algorithm to control the operation factors of the proposed hybrid filter under hybrid power supply was developed, tested, and evaluated. Practical recommendations for industrial application of the proposed hybrid filter are given. Keywords: Distributed generation Harmonics Hybrid filter Hybrid power supply Power quality This is an open access article under the CC BY-SA license. Corresponding Author: Yuriy Sychev Department of Power Engineering and Electromechanics, Faculty of Energy Saint-Petersburg Mining University 21 Line, 2 (Vasilievskiy Island), Saint Petersburg 199106, Russian Federation Email: ya_sychev@mail.ru 1. INTRODUCTION Nowadays distributed generation technologies have a wide range of application in different industrial and public power supply systems [1]. Such technologies are based mainly on wind farms, solar power stations [2], and microturbine installations, which work on associated petroleum gas [3], [4]. They help to improve the reliability of power supply from public centralized networks. This is especially important for business and industrial users as voltage dips or interruptions can disrupt production [2]. In different countries, the role of distributed generation technologies depends on the structure of the existing power supply systems, electricity prices, and the features of power supply markets [5]. There are two ways in which distributed generation can be performed: it can work separately or in parallel with any existing centralized power supply system. The latter method for ensuring uninterruptible power supply is more widespread and can be called a hybrid power supply system or a grid-connected renewable energy system [3], [6]. In addition, in many countries, conventional centralized or public power supply systems are very old and unreliable but they cannot be replaced immediately by distributed generation [7]. Therefore, hybrid power supply systems may be considered as a real alternative to the existing public networks when the rated power of distributed generation systems is not enough to ensure that all industrial consumers are provided with