Research Article Modified Fast Terminal Sliding Mode Control for DC-DC Buck Power Converter with Switching Frequency Regulation G¨ uven Balta , 1 NakiG¨ uler , 2 andNecmiAltin 2 1 Department of Electrical and Electronics Engineering, Faculty of Engineering and Architecture, Erzurum Technical University, Erzurum, Turkey 2 Department of Electrical and Electronics Engineering, Faculty of Technology, Gazi University, Ankara, Turkey Correspondence should be addressed to Necmi Altin; naltin@gazi.edu.tr Received 19 March 2022; Revised 22 September 2022; Accepted 14 October 2022; Published 31 October 2022 Academic Editor: Shaofeng Lu Copyright © 2022 G¨ uven Balta et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In this paper, a modifed fast terminal sliding mode control (FTSMC) with a fxed switching frequency is proposed for regulating the output voltage of the DC•DC buck converters. Te design steps of the proposed FTSMC such as the selection of sliding surface, switching control strategy, existence, robustness, and stability analysis are presented in detail. To overcome the variable switching frequency in FTSMC, a frequency control loop is designed. Moreover, the proposed FTSMC with fxed switching frequency can be implemented by using only one voltage sensor. Hence, the proposed control method not only ofers a fast dynamic response and fxed switching frequency but also simplifes the controller design in practical implementation. Te efectiveness of the proposed control methods has been investigated by experimental studies. Te results reveal that the proposed methods exhibit a good performance under both steady•state and dynamic transients caused by the variations in load resistance, input voltage, and reference voltage. Moreover, the proposed method is compared with four existing methods. 1.Introduction Te improvements in technology have caused massive de• velopments in many felds such as industry, manufacturing, medical, communication, mechanics, energy, and military, over the past decade. Power converters are widely used almost in all of these felds. Terefore, the interest in power converters is increasing, day by day. On the other hand, power components have undergone a fast evolution. As a result of this evolution, some improvements are achieved in terms of cost, energy consumption, size, efciency, and lifetime [1, 2]. Tese improvements are also refected in electronic circuits which use power components. Hence, the size, cost, and weight of the power electronic systems are reduced while the efciency is increased [3]. DC•DC converters are an example of powerful and sophisticated electronic circuits which is structured with the improved power components. Generally, DC•DC converters are utilized as a power supply in a similar fashion to the traditional linear power supplies. In comparison to linear alternatives, DC•DC converters have a lot of outstanding advantages such as stepping up/down, reversing the polarity of the output voltage, a higher efciency, operating in a much larger DC input voltage range, the ability to operate in a wide input voltage range, [4, 5] lower power loss, smaller• size, and cost•efective structure [6]. All of these qualities are paving the way for DC•DC converters to become more widespread. Hence, they are used as replacements for the linear counterparts in many areas where higher efciency and smaller size or lighter weight are required [7] such as personal computers, computer peripherals, communication, medical electronics, and adapters of consumer electronic devices [8]. Tere are various types of DC•DC converters that are derived from modifying the location of the advanced power components. Te main types of DC•DC converters can be described as buck, boost, and buck•boost converters. Tese converters are used to convert DC input voltage at a certain level to obtain a regulated DC output voltage at a diferent level with very high conversion efciency [6] for static and Hindawi International Transactions on Electrical Energy Systems Volume 2022, Article ID 5076611, 17 pages https://doi.org/10.1155/2022/5076611