Calculation of the transformers and electric machines characteristics

Abstract

This edition is dedicated to the implementation of calculation task "Calculation of the transformers and electric machines characteristics" on the discipline "Electric machines". The purpose of this discipline is to consolidate theoretical knowledge and develop practical skills for calculating the characteristics of transformers, alternation current (AC) electric machines and direct current (DC) electric machines. The objects of study are transformers and electric machines, which are the basis of electric power in various industries. The subject of this discipline are the electric machines, which are used in practice to convert one form of energy into another: mechanical energy to electrical (the generators), electrical energy to mechanical (the engines), and power transformers, which are used to convert the meanings of alternating current and voltage. After training, the student must know the structure, basic elements of the transformers and electric machines, there operation principle and characteristics, peculiarities of motors starting, the ways of rotation frequency control and braking. The student should be able to evaluate new electrical equipment, take into account technical and economic requirements. This assignment consists of five tasks. For each part, control questions and tasks are formulated, recommendations for their solution are given. Calculation tasks are the student’s final document to complete the discipline. The report on the done work must be finished in written form and defended by the examination date. The tasks and the volume of the work must be agreed by the lecturer of this discipline. The report should begin with a cover page, the sample of which is given in Appendix A. When drawing up a report, it is necessary to formulate the task, show the procedure for performing calculations: write down a formula, and then put numbers in this formula and show the result of the calculation. The report should contain the necessary diagrams and graphs. At the end of the report student has to give the list of information sources used in the work. Graphs and diagrams should be built on graph paper, indicating the scale and dimension of the physical quantity on the axes. If the graph was built on a regular sheet of paper, then a uniform "grid" should be drawn on the graph field. Students choose the number of a variant for the work according to the number in the academic group list. New modern notation symbol system of electrical, magnetic, mechanical and energy values, which correspond to the state standards, are used in this study course.