Comprehensive power supply system for the car repair plant
Students Name: Lakotskyi Pavlo Romanovych
Qualification Level: magister
Speciality: Electrotechnical Systems of Electricity Consumption
Institute: Institute of Power Engineering and Control Systems
Mode of Study: full
Academic Year: 2021-2022 н.р.
Language of Defence: ukrainian
Abstract: The car repair plant is a powerful modern enterprise with a deep history, when a small town organized a car repair shop for the overhaul of GAZ-MM engines. A few years later, the workshop was equipped with equipment for the production of springs. The company was tasked to produce 150 tons of spring products per year. In 1960, the workshop was renamed the car repair shop. The number of employees increased to 400 people. The plant’s products include a wide range of spare parts for car trailers, springs and spring sheets for Bogdan buses and GAZELLE minibuses. In 2008, the plant launched a thermal line and is mastering the production of spring sheets for KRAZ, KAMAZ, ZIL and MAZ trucks. At the same time, the production of auto parts is being established: spring fingers and pins. In 2009 the company began to produce springs and spring sheets for minibuses "Mersedes", "IVECO", "HYNDAY". At the same time, the production of spring products for HTZ tractors and trolleybuses of domestic and foreign production was established. For production of springs the enterprise uses high-quality spring steel of the 60S2A, 50HGA, 55C2 brands. The dynamic development of the plant is ensured through constant modernization and improvement of technologies. In the section electrical loads, the calculated electrical load of the repair-mechanical modified statistical method (MSM) for the second (To = 10 min.) And third levels (To = 150 min.) Power supply is determined by the exact value of the consolidated number of receivers [2]. Estimated electrical loads of other shops and the plant as a whole were determined by the demand factor method. Also in this section, a mapping of electrical loads was calculated to determine the center of electrical loads. The section "Choice of external power supply scheme" defines the number and capacity of GZP transformers. The choice of the optimal cross section and line voltage by the method of unconditional optimization is carried out. The selected wire was also tested under the conditions of allowable heat load and voltage losses. In the section "Internal power supply scheme of the enterprise" the places of installation of shop switchgears and LV are determined, the number and power of transformers of shop transformer substations (STS) and reactive power compensating charters are selected, the configuration of internal power supply circuit is selected and the cable is selected. The technical and economic comparison of variants of the scheme of internal power supply by the method of discounted costs is carried out. The reactive power balance is also summarized in this section. To select and test switching devices, short-circuit currents were calculated. The calculation was performed in accordance with DSTU [3, 4]. In the section "Determining the efficiency of SES" the calculation of the installation of solar panels on the roof of one of the shops and the efficiency of investment in the construction of SES In the section "Steady-state modes of the power supply system" the calculation of steady-state normal and emergency modes of the power supply system is performed. The main purpose of these calculations is to determine the provisions of the on-load tap-changer and PBZ transformers GZP and shop TP and determine the calculated values of voltages on the busbars of substations. In some cases, such calculations may be the basis for special measures to normalize one of the most important indicators of voltage quality - voltage deviation. Selected positions of branches of on-load tap-changers and PBZ of transformers provide indicators of quality of the electric power according to GOST 13109-97 [5]. To protect the transformers of the main step-down substation, the relay protection was calculated. As a result, a comprehensive power supply system of the car repair plant was developed, which is reliable and economically justified and provides consumers with high quality electricity in full in accordance with current legislation [6]. Object of research - a complex power supply system of a car repair plant; The subject of the research is the choice of the optimal technical and economic variant of the power supply system, the design of the external and internal power supply system of the facility with the introduction of advanced technologies and the use of a solar power plant. As a result of the study of the object: the calculation of the load according to DBN B.2.5-23: 2010 [7]; the calculation of reactive power compensation devices was performed; the scheme of external power supply of the object is selected; short-circuit currents are calculated; the equipment of the switchgear of the object is selected; switching devices and cable lines are selected, solar power plant equipment is selected. Keywords: transformers, lines, cable lines, protection, automation. References. ДСТУ ISO 9001:2015 Системи управління якістю. Вимоги (ISO 9001:2015, IDT). Проектування електропостачальних систем загального призначення/П.Ф. Гоголюк, Т.М. Гречин, А.А. Маліновський, О.М. Сівакова, Є.І. Федів, Б.К. Хохулін. – Львів: Видавництво Львівської політехніки, 2018. – 436 с. ДСТУ IEC/TR 60909-0:2007. Струми короткого замикання у трифазних системах змінного струму. Частина 0. Обчислення сили струму короткого замикання в трифазних системах змінного струму. – К: Держспоживстандарт України, 2008. ДСТУ IEC/TR 60909-4:2008. Струми короткого замикання у трифазних системах змінного струму. Частина 4. Приклади обчислення сили струму короткого замикання. – К: Держспоживстандарт України, 2009. ГОСТ 13109-97. Электрическая энергия. Нормы качества электрической энергии в системах электроснабжения общего назначения. – К.: Изд-во. Стандартов, 1999. – 31 с. Правила улаштування електроустановок. – К.: Міненерговугілля, 2017.– 760 с. Проектування електрообладнання об’єктів цивільного призначення, Державні будівельні норми України ДБН В.2.5-23:207.