Study of the impact of SPP on the electricity supply system of the enterprise and the network of the distribution system operator
Students Name: Dudii Rostyslav Vitaliiovych
Qualification Level: magister
Speciality: Renewable Energy Systems and E-mobility
Institute: Institute of Power Engineering and Control Systems
Mode of Study: full
Academic Year: 2024-2025 н.р.
Language of Defence: ukrainian
Abstract: An electricity supply system is a set of facilities and technologies that provide electricity to consumers. It includes power plants, power transmission networks, and distribution systems. Generating stations can use different energy sources, such as coal, gas, nuclear fuel, solar and wind energy. Electricity generated at the plants is transmitted through high-voltage power lines to substations, where its voltage is reduced for further distribution to end users. Basic principles of power supply system design: 1. The system must be designed to take into account geographical conditions, consumer location, projected load, and potential emergencies. Reliability is ensured by redundancy of the main elements of the system, the use of automated monitoring and control tools. 2. The design should focus on maximum energy efficiency. This includes optimizing the operation of power sources, minimizing losses in networks, analyzing the condition of transformers, and planning optimal power transmission routes based on load and distance to consumers. 3. The system should be able to adapt to changes in consumption patterns, the connection of new facilities and the use of innovative energy sources. It is important to consider the prospect of load growth and technological changes, such as the integration of renewable energy sources or distributed generation. 4. The design should take into account the optimal ratio of the cost of construction, operation and maintenance of the system. It is important to ensure the rational use of resources, reduction of capital and operating costs. 5. The system should guarantee stable voltage, frequency and quality of electricity. This includes the use of equipment to compensate for reactive power, eliminate harmonics, stabilize voltage, and implement protection against short-term interruptions. 6. The design of power supply systems should be aimed at minimizing the environmental impact. This is achieved by introducing environmentally friendly technologies, using renewable energy sources, reducing emissions and energy losses. 7. The introduction of modern automated monitoring and control systems allows to increase the efficiency and reliability of the system, to ensure a quick response to changes in load or emergencies. The object of study is the power supply system of the operator of the distribution and power supply system of a confectionery enterprise in Kremenchuk. The subject of the study is the feasibility of using a solar power plant at an industrial facility and its impact on the power supply system. Purpose: to study the operation of the power supply system of a confectionery enterprise with joint power supply from the grid and solar panels and its impact on the distribution system operator’s network. The first step was to calculate the active, reactive and total load for each building and the facility as a whole. Next, we selected the optimal cross-sections of the external power supply lines. Based on this data, we assessed the economic feasibility of installing a main step-down substation or switchgear. Taking into account the estimated load, we determined the number of transformers required for the system and calculated the compensated reactive power for each building separately. After that, we formed groups of buildings and selected transformers to power each of them, calculated the short-circuit current to select the minimum permissible cable line cross-sections and compare the main and radial internal connection schemes, calculated line lengths, optimal cable cross-sections, and discounted costs for laying them. After that, we re-calculated the short-circuit parameters, taking into account the specifics of the chosen scheme. We also determined the characteristics of renewable energy sources and how to connect them to the grid. The next step was to determine the list of switching equipment and develop a basic electrical circuit of the grid. In the process, we studied the generation of reactive energy at maximum active power under the condition of clean and complex generation. It turned out that in the case of clean generation, the operation of the internal network in this form was impractical, so a capacitor unit was added to the 0.4 kV substation busbars. However, the integrated generation showed us a significant margin of reactive energy consumption. In conclusion, we created a detailed diagram of the power grid using the Dakar software environment and analyzed the system’s operation in normal post-emergency and repair-emergency modes for our facility. All considered variants of operating modes, including normal, emergency and repair modes, successfully passed the reliability test. This indicates a high level of stability and reliability of the power grid, which guarantees uninterrupted power supply to consumers even in the event of unforeseen situations. The voltage drop on the facility’s buses does not exceed 8%, which indicates the high efficiency of the system and competent network design. This ensures a stable quality of electricity for consumers.