Journal on Advanced Research in Electrical Engineering, Vol. 7, No. 1, Jan. 2023 52 © 2023 by the authors. This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. How to cite: Vesali, M. (2023). A method to calculate and measure losses and efficiency in DC-DC converters. JAREE (Journal on Advanced Research in Electrical Engineering), 7(1). Abstract— In this paper, training on how to calculate and measure losses in power converters is presented. In the power converters all elements have losses due to circuit conditions, therefore in order to calculate the losses in the elements, all conditions are considered, so the accuracy of the calculations are high. All relationships and formulas to calculate losses are presented, so the different ways of calculating losses are clear in this paper. All basic converters in this paper are studied in term of losses, so this paper is a good reference for calculating losses in DC-DC converters. In converters with soft switching, elements are added that also have losses in the converter, which the method for obtaining losses of these elements is also taught. Finally, methods for obtaining losses in simulation and experimental prototypes are given that prove the methods and theoretical formulas. Keywords— DC-DC converter, losses, efficiency. I. INTRODUCTION Today, DC-DC converters have become very important in the industry [1], so that they are available in almost all sectors in the industry. These converters are used as power supply circuits [2]. Some of the important applications of these converters are in microprocessor computers [3],[4], electric vehicle system [5-8], photovoltaic systems [9-12], led drive [13-15], wind energy systems [16]-[18], office equipment [19- 21] and etc. In general, these converters are either linear or switching. Linear converters or regulators are less used due to high losses and are used only in special cases [22-25]. Therefore, switching converters have received more attention, which reduces losses and increases efficiency with this technique [26]. Switching converters are divided into two general categories, isolated [27] and non-isolated [28]. The structure of non-isolated converters is simpler and has higher efficiency [29]. Transformers are used to isolate the converters [30]. The use of transformers causes losses in the converters and the efficiency of these models is lower than non-isolated. Non- isolated converters are divided into buck [31], boost [32], buck- boost [33], CUK [34], SEPIC [35] and ZETA [36]. isolated converters are divided into fly-back [37], forward [38], half- bridge [39] and full-bridge [40]. Of course, new types of converters have also been introduced [41], which all of these topologies are derived from the basic topologies mentioned. In all switching converters the elements such as diode, switch, inductor and capacitor are used, which these elements have losses and should be considered in design. Losses in these converters are divided into conduction and switching losses. Conduction loss is related to the current and voltage on the element, but switching loss is related to switching the elements on and off with the desired frequency. To reduce conduction losses, the type of element and power of the converter is important, the use of elements with small on-state resistance reduces these losses. In the switching mode, due to the high speed of turning off and on the element, there is an overlap between the voltage and current, which creates the sum of these overlaps in the switching loss converter. In hard switching converter losses are high than soft switching converter, because in soft switching, ideally, the overlap of voltage and current is eliminated and the switching losses are zero. Today, these converters are offered completely in the form of soft switching to have high efficiency and reduce losses. However, there are losses in these elements and cause a decrease in efficiency. Therefore, calculation and measurement methods should be provided. Also, in most references, the comparison of efficiency and losses between the proposed converter with the hard switching converter has been done, which should be provided the calculation method in all converters, including basic converters. So far, no complete references have been presented on the loss and efficiency calculations, and the papers that have mentioned the losses are given briefly and only for a part of the paper structure. In this paper, calculated of losses in the switching converters is presented. These calculations are presented completely in full detail. Section 2 describes all the elements and their specifications in switching converters. Section 3 shows how to calculate the losses of each element in full, also mentioned all the relationships. Section 4 describes how to obtain converter efficiency in an experimental prototype. In Section 5, a comparison is presented between the paper and previous papers based on loss calculations. Finally, section 6 presented the conclusion of the paper. Mahmood Vesali Department of Electrical Engineering, Isfahan (khorasgan) Branch, Islamic Azad University, Isfahan, Iran mahmoodvesali645@gmail.com A Method to Calculate and Measure Losses and Efficiency in DC-DC Converters