5 1. The electrical exhibition organized in St. Petersburg consisted of eight sections: telegraphy and telephony, electric lighting and electro-mechanics, electricity in the army and navy, galvanoplastics, electricity in education, electrical measuring instruments, electrophony, and literature and pictorial material on electricity. The exhibition showcased the works of notable Russian inventors such as Yablochkov, Lodygin, Rikhter, Ragozin, and Teplov in these various sections. 2. At the end of the XIXth century, the financial state of Technical Societies in Russia was challenging. There were only a few specialized scientific research institutions, particularly of the applied type. The funds allocated for scientific purposes were insignificant, which led the Russian scientific societies to rely on their own money to address scientific problems and advance their programs. They had to coordinate the efforts of individual investigators and undertake a broad program of disseminating scientific knowledge. 3. The Russian Technical Society, particularly its Sixth Department, played a significant role in providing educational activities. They organized public lectures and events to spread scientific knowledge and attract the interest of individuals, especially the youth, in the new technical field. For example, they invited O. Khvolson, an honored professor at St. Petersburg University, to deliver a series of public lectures on “Electricity and Magnetism.” These lectures drew large crowds of students from various schools in the capital, as well as individuals already working in the field of electricity. 4. Well-known Russian scientists made advancements in various areas of science, technology, and education. Specifically, in the field of electrical engineering, notable Russian inventors and scientists such as Yablochkov, Lodygin, Rikhter, Ragozin, and Teplov contributed to the development of telegraphy, telephony, electric lighting, electro-mechanics, galvanoplastics, and electrical measuring instruments. 5. The Sixth Department of the Russian Technical Society played a prominent role in the history of electrical engineering in Russia. In prerevolutionary Russia, with only a few specialized scientific research institutions, the Sixth Department took on the task of coordinating efforts, addressing scientific problems, and disseminating scientific knowledge. They organized an electrical exhibition in St. Petersburg during their first year, which not only paid for itself but also generated a considerable profit, becoming the main source of financing for the first electrical journal. This exhibition showcased the works of renowned Russian inventors and scientists. 6. The Russian Society of Physics and Chemistry and the Russian Technical Society held different positions at the end of the XIXth century. The Russian Society of Physics and Chemistry was associated with St. Petersburg University, while the Russian Technical Society was an independent scientific corporation. The Russian Technical Society had its own Sixth Department, which focused on electrotechnical matters and had its journal called Electricity. 7. The Sixth Department of the Russian Technical Society played a crucial role in the development of electrical engineering in prerevolutionary Russia. Given the limited number of specialized scientific research institutions, the department used its own funds to address scientific problems and coordinate the efforts of individual investigators. They also conducted a broad program of spreading scientific knowledge, organizing events like the electrical exhibition. The financial success of the exhibition allowed them to establish the first electrical journal, further contributing to the advancement of electrical engineering in Russia. Overall, the Sixth Department’s activities were instrumental in promoting and supporting the field of electrical engineering during that time. 1 1. Electric Power Systems perform the following functions: Generation: Producing electricity from various sources such as thermal power plants, hydroelectric power plants, nuclear power plants, wind farms, and solar power plants. Transmission: Transmitting electrical energy at high voltages over long distances through power lines. Distribution: Distributing electricity from transmission lines to endusers, such as residential, commercial, and industrial consumers. Control and Protection: Monitoring and controlling the flow of electricity, ensuring the stability and reliability of the power system, and protecting it from faults and overloads. Load Management: Balancing the supply and demand of electricity to ensure a stable and efficient operation of the power system. Power Quality Management: Maintaining the quality of electrical power within acceptable limits to meet the requirements of different types of electrical equipment and systems. 2. The important economic advantages of the production and transmission of energy in the form of electricity are: Efficiency: Electricity production can achieve high efficiency levels compared to other energy forms. Centralization: Power generation in central power plants allows for economies of scale, reducing overall costs. Long-Distance Transmission: Electricity can be transmitted over long distances with minimal losses, allowing power plants to be located far from population centers and energy sources to be utilized efficiently. Flexibility: Electricity can be easily converted into different forms of energy, such as mechanical, heat, or light, providing versatility in its applications. Reliability: Electrical power systems can be designed and operated to provide a reliable and continuous supply of electricity, minimizing disruptions and downtime. 3. The process of hydroelectric power utilization at a distance from the source involves harnessing the power of flowing or falling water at a hydroelectric power plant located near a water source such as a river or dam. The mechanical energy of the water is converted into electrical energy using turbines and generators. The generated electricity is then transmitted through high-voltage transmission lines to distant areas where it is needed for various purposes, such as residential, commercial, or industrial consumption. 4. Alternating current (AC) is generally used in modern power systems for several reasons: AC can be easily transformed to different voltage levels using transformers, allowing for efficient transmission and distribution of electrical energy. AC enables power transfer over long distances with reduced losses compared to direct current (DC). AC allows for easy implementation of synchronized grid systems, enabling the interconnection of multiple power sources and facilitating power sharing and system stability. AC is more suitable for most common electrical appliances and devices used in homes, offices, and industries, as they typically operate on AC power. 5. The main elements of a modern electric power system include: Power Generation Plants: These include thermal power plants, hydroelectric power plants, nuclear power plants, wind farms, solar power plants, and other renewable energy installations. Transformers: Used to step up or step down the voltage levels for efficient transmission and distribution of electricity. Transmission Lines: High-voltage power lines that transport electricity over long distances from power plants to substations or directly to large industrial consumers. Substations: Facilities where voltage levels are adjusted, and electricity is distributed to different areas through distribution lines. Distribution Lines: Lower voltage power lines that deliver electricity to residential, commercial, and small industrial consumers. Consumers: The end-users who utilize electricity for various purposes. 6. Transformers are used for voltage transformation in an electric power system. They can step up or step down the voltage levels as required for efficient transmission and distribution of electricity. Step-up transformers increase the voltage for long-distance transmission to minimize losses, while step-down transformers decrease the voltage for safe and appropriate use by consumers. 7. Substations are facilities where the voltage levels in an electric power system are adjusted, and electricity is distributed to different areas. At substations, transformers are used to step down the transmission voltage to distribution levels, and switching equipment is installed to control the flow of electricity. Substations also provide points for monitoring and protection of the power system. 8. A typical central electric station operates generators at high voltages, usually in the range of thousands of volts. These generators produce electrical energy through various means such as steam turbines, gas turbines, hydro turbines, or wind turbines. 9. The main element of the central station of a power system is the power generation plant. This can include multiple generators operating on different energy sources, such as thermal, hydro, nuclear, or renewable sources. The central station is responsible for producing the bulk of the electrical energy supplied to the power system. 10.In the early 1990s, most of the world's electric power was generated using various installations, including thermal power plants (fueled by coal, oil, or gas), hydroelectric power plants, nuclear power plants, and some early renewable energy installations such as wind farms. 11.The lines of high-voltage transmission systems are usually composed of conductors made of aluminum or copper, supported by towers or pylons made of steel or concrete. These lines may also include insulators and lightning protection equipment to ensure safe and reliable transmission of electricity. 12.The distance between towers in high-voltage transmission lines can be increased by using taller towers, longer spans between towers, or by using specialized techniques such as bundle conductors or corona rings to control electrical losses and maintain system integrity. 13.Insulated underground cables are used for distribution in cases where it is not feasible or desirable to have overhead power lines. They are commonly used in urban areas, densely populated areas, or environmentally sensitive areas where aesthetics, safety, or space constraints make underground installation preferable. 14.Pipe-type cables, filled with oil at high pressure, are used in applications where a high level of insulation is required, such as in high-voltage direct current (HVDC) transmission systems. These cables are designed to withstand high voltages and provide efficient power transmission over long distances. 15.Yes, an electric-distribution system involves a large amount of supplementary equipment. This includes circuit breakers, transformers, voltage regulators, protective relays, capacitors, meters, switches, and various monitoring and control devices. These equipment and devices are essential for ensuring the safe, reliable, and efficient operation of the distribution system. 16.Circuit breakers are used in an electric power system to protect the system from faults, overloads, and short circuits. They are designed to interrupt or break the flow of electrical current in the event of abnormal conditions. Circuit breakers help prevent damage to equipment, ensure the safety of personnel, and maintain the overall stability and reliability of the power system. 2 1. Electric Power Systems are the systems used for the conversion of other types of energy into electrical energy. 2. Electric Power Systems are the systems used for the transmission of energy to the point of consumption. 3. In modern power systems, alternating current is generally used. 4. Electric Power Systems consist of several main elements. 5. Transformers are used to regulate generated power. 6. In Electric Power Systems, voltage is stepped up and down by means of transformers. 7. A prime mover at the central station of a power system operates an electrical generator. 8. Most of the world's electric power in the early 1990s was generated in various installations. 9. Wooden poles are generally used for medium voltage subtransmission and distribution lines. 10.Any electric-distribution system involves a large amount of equipment for the protection of generators, transformers, and the transmission lines themselves. 11.Circuit breakers are employed to protect all elements of a power system from short circuits and overloads. 12.In large air-type circuit breakers, magnetic fields are used to break up the arc. 4 1. The Electric Power System involves the transformation of energy into electrical energy and its transmission to the point of consumption. 2. The utilization of power in the form of electricity offers significant economic advantages due to its cost-effectiveness. 3. A power station typically consists of a generator, which is the prime mover responsible for producing electrical energy. 4. Transformers play a crucial role in the Electric Power System by stepping up or stepping down voltage levels at different stages of the system. 5. Transmission lines are used to transmit electrical energy over long distances from the power station to substations. 6. Substations are essential components of the power system as they step down the voltage to a level suitable for distribution on subtransmission lines. 7. Consumer's equipment refers to the devices or machinery used by end-users to utilize the electrical power delivered to them. 8. Insulation is necessary in power systems to prevent electrical breakdown and ensure safe and efficient transmission. 9. Power loss in a system is directly proportional to the square of the current flowing through it. 10.The voltage is stepped down again at the point of use through distribution transformers, which deliver power to consumers at lower voltages. 11.High-voltage AC can be converted to high-voltage DC using modern solidstate rectifiers, minimizing capacitive and inductive losses during transmission. 12.Nuclear energy is one of the sources used to generate electric power in steam plants. 13.Circuit breakers are employed in power systems to protect against short circuits, overloads, and for normal switching operations. 14.Liquid dielectric, such as oil, is used in some circuit breakers to extinguish the arc formed when the current is interrupted. 15.Supplementary equipment, such as voltage regulators, is used to maintain the desired voltage levels and improve the power factor in the system. 5 The five main ideas of the text are: 1. Electric power systems involve the transformation of various forms of energy into electrical energy and its transmission to the point of consumption. 2. The use of alternating current (AC) and transformers allows for efficient operation at different voltage levels throughout the system. 3. The electric power system consists of interconnected elements such as power stations, transformers, transmission lines, substations, and consumer equipment. 4. High-voltage transmission lines, made of materials like copper or aluminum, are used to transmit electricity over long distances, while subtransmission and distribution lines use wooden poles or underground cables. 5. Safety measures, such as circuit breakers and supplementary equipment, are employed to protect the system from short circuits, overloads, and voltage fluctuations. 7 1. The conversion of mechanical energy into electrical energy is carried out at modern power stations. 2. Electric power systems are an important component in the economy of any developed country. 3. Generation and transmission of electrical energy to the point of consumption is the main function of modern electric power systems. 4. Transmission of electricity through high-voltage power lines is a costeffective method of transferring energy over long distances from the generation site. 5. Alternating current can be easily transformed in both voltage up and down directions using transformers. 6. A modern power system consists of six main elements, each of which performs a specific function. 7. High voltages are undesirable due to the risk of insulation damage. 8. The higher the voltage on the line, the lower the current magnitude, and consequently, lower energy losses during transmission. 9. This power station uses fuel oil as its primary fuel. 10.Copper, aluminum, and steel wires are used in high-voltage power transmission lines. 11.The distance between supports of high-voltage power transmission lines depends on the material used for the wires. 12.Wooden poles are used instead of steel towers for local and distribution power lines. 13.Circuit breakers are used to protect all components of the power system from short circuits and overloads. 14.In the event of a sudden increase in current magnitude, circuit breakers automatically disconnect the power supply.