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Basic Electronics
Published in Julio Sanchez, Maria P. Canton, Microcontroller Programming, 2018
Julio Sanchez, Maria P. Canton
When current flows through a coil it produces a magnetic field in the space outside the wire. This makes the coil behave just like a natural, permanent magnet. Moving a wire through a magnetic field generates a current in the wire, and this current will flow through the associated circuit. Since it takes mechanical energy to move the wire through the field, then it is the mechanical energy that is transformed into electrical energy. A generator is a device that converts mechanical to electrical energy by means of induction. An electric motor is the opposite of a generator. In the motor electrical energy is converted to mechanical energy by means of induction.
Environmental Health Emergencies, Disasters, and Terrorism
Published in Herman Koren, Best Practices for Environmental Health, 2017
Power outages are not only inconvenient but also create many potential environmental problems. Food may spoil and become inedible or potentially cause disease. Water may become contaminated because of loss of function of water purification systems. Extreme heat or cold may cause discomfort and severe conditions leading to illness and death. Portable generators if used within structures may cause carbon monoxide poisoning. Dangerous situations may occur when working in the vicinity of downed wires and lead to electrocutions, which are a common cause of occupational deaths.
Hydropower and Marine Energy
Published in Radian Belu, Fundamentals and Source Characteristics of Renewable Energy Systems, 2019
The power generation industry almost exclusively uses large synchronous generators, as they have the advantage of a variable reactive power production, i.e., voltage control. There are two most common used types of generators: synchronous and asynchronous electric machines. However, DC (direct current) electric generators are sometimes used, especially for pico-hydroelectric applications. An electric generator is a device that converts mechanical energy to electrical energy. A generator forces electric current to flow through an external circuit. The source of mechanical energy may be a reciprocating or turbine steam engine, water falling through a turbine or waterwheel, an internal combustion engine, a wind turbine, a hand crank, compressed air, or any other source of mechanical energy. Generators provide nearly all of the power for electric power grids. An electric generator uses the rotor shaft speed and torque to convert mechanical energy to electrical energy with the use of electromagnetic fields. The main concern with generators in hydroelectric turbines is that they must produce electricity compatible with that in the electrical grid, if the system is grid connected for the given site. In America, the grid is at 60 Hz, while in most parts of Europe the grid runs at 50 Hz. The electricity must have the same characteristics, be of sufficient quality, and be connected in such a way as to not interrupt the existing current flow. The function of an electrical generator is providing a means for energy conversion between the mechanical torque from the hydro rotor turbine, as the prime mover, and the local load or the electric grid. Different types of generators are being used with hydroelectric system, induction (asynchronous), synchronous, or occasionally DC electric generators.
Pump Insole with Mini AC Generator for Emergency Energy
Published in Electric Power Components and Systems, 2023
Musaddak Maher Abdul Zahra, Bashar Mahmood Ali, Hailer Sharif, Ahmed Read Al-Tameemi, Ali Al Mansor, Abdul Razzaq T. Zaboun, Saja Hameed Kareem, Ahmed A. Ali, Ilhan Garip, Karthikeyan Sathasivam
Figure 3 shows a generator and gearbox designed to convert mechanical energy generated from human footsteps into electrical energy by the generator. This energy will then be converted into electricity by the gearbox. The gearbox will be driven by the human footstep and convert the mechanical energy of the footstep into rotational mechanical energy. The generator will then convert this rotational energy into electrical energy, which can power a device or appliance [9]. The mechanical energy from the generator is converted into electrical energy by generating a rotating electromagnetic field that induces a current in the generator’s winding. The diodes act as rectifiers and convert the alternating current produced by the generator into direct current. The capacitors help to smooth out spikes in the voltage. The IC 7805 then regulates the voltage output to a maximum of 5 V to provide stable output. The DC step-up is necessary to increase the voltage to the required level for the load. Without the step-up, the energy would not be able to be stored in the battery, and the load would not be able to be powered. The current can vary in every test due to several factors and variables that influence the flow of electric charge through a circuit. Resistance, Voltage Source, Component Variations, Temperature, Load Variations, Measurement Errors. It’s important to note that in some cases, intentionally changing certain factors, such as resistance or voltage, during tests is necessary to observe the behavior of circuits under different conditions. These variations help in analyzing and understanding the characteristics and limitations of the circuit components.
Research on power quality control of grid-connected microgrid based on distributed generation
Published in International Journal of Ambient Energy, 2022
Jian Wu, Xue Jin, Tao Yin, Qun Liu, Shaochun Yan
In addition, the mechanical energy transmitted by the wind turbine to the transmission system is converted to electrical energy according to the electromagnetic induction principle. There are two types of generators: synchronous generators and asynchronous generators. Winded doubly fed induction fan set has been widely used because of its high utilisation rate of wind energy and high stability of the system. At present, W wound doubly fed induction generator set is mainly used in newly built multi-W wind farms at home and abroad, whose power generation system is shown in Figure 2.
Review on automatic generation control strategies for stabilising the frequency deviations in multi-area power system
Published in International Journal of Ambient Energy, 2022
K. Peddakapu, M. R. Mohamed, P. Srinivasarao, A. S. Veerendra, D. J. K. Kishore, P. K. Leung
The electrical generator converts mechanical energy into electrical energy. The outcome of the generator is regulated by the driving torque of the turbine. The turbine output is depending on the amount of steam/water flowing through the inlet. When the loads on the generator either increase or decrease then automatically fluctuations occurring in generator speed then immediately frequency altered thus, the system becomes unstable. Therefore, the speed governor system senses by the deviations in generator speed on the account of a mismatch between generation and demand associated with the losses.