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Through this document, it is intended to provide a guide for the acquisition of a 10kW electric power generator with biogas, using a series of steps that are proposed in this article for the adequate obtaining of the generator that comply the specific demand of this case and will be installed in the Market Square of Fusagasugá (Colombia), the main collection center of the municipality and that constitutes this case of study. The methodology consists in the compilation of the options for their acquisition according to market availability, electrical and mechanics specifications, accessories, nationalization and internal transport procedures.

In this article, a method of winding optimization of the linear generator is proposed to increase the electrical power generation from the oceanic wave. A linear generator is designed in the ANSYS/Maxwell environment to analyze the proposed winding optimization method. The electrical and magnetic properties of the generator are extensively analyzed. The cross-sectional area and the number of turns of the copper conductor are optimized to maximize the output power. Load characteristics are also considered for different conductor sizes and turn numbers to determine a suitable operating point. A cooling system is also incorporated in the optimized linear generator to extract the thermal energy produced during the operation, which eventually enhances the electrical power generation. It is found that the optimized linear generator finally generates around 42% more electrical power compared to that of the conventional one. Therefore, the volumetric power density of the linear generator is noticeably increased with the proposed optimization method that also results in the minimization of material cost of the generator. A downscale prototype of the linear generator is constructed in the laboratory. It is expected that the proposed winding optimization method can be used in designing other linear generators.

In the present study, we investigated the design and performance of a small hybrid magnetic generator. With small solar electrical generators, the permanent magnetics are replaced with an assisted rotating field. The rotor and stator were fabricated with a magnetic and coil windings unit, in which the rotor set includes 48 NeFeB magnets and eight salient poles with coil windings for the stator. The DC from solar energy assists the induced magnetic field of the copper winding, making the rotor rotational. The copper windings and permanent magnet bars significantly affected the rotor rotational speed and obtained energy output capacity. We investigated two different systems for the solar electric generator. For Case I, input and output energy capacities were 4.98Ah and 3.53Ah, whereas for Case II, the input and output energy capacities were 3.79Ah and 2.95Ah. To obtain higher performance, three different operating conditions were performed. We found that the condition with four copper windings running in on-off mode every 12 min and four copper windings running continuously produced the highest performance (133.33%). This means that the output energy is higher than the input energy. The results are expected to provide guidelines for designing small solar electric generators for rural environments.

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Most of the conventional linear generator is constructed with either Alnico (specially AlNiCo‐9) or Neodymium iron boron (NdFeB) permanent magnets (PMs) for harvesting oceanic wave energy. Alnico is a composition of aluminium (Al), nickel (Ni), and cobalt (Co) added to iron, which is its major volumetric component. Alnico has a poor magnetic energy product, and NdFeB contains a rare earth element. To overcome this issue, a recently developed rare‐earth free iron nitride (Fe16N2) compound‐based PM linear generator (PMLG) is proposed in this study as an alternative solution for avoiding rare earth material while obtaining high output power. To the best of authors' knowledge, newly invented Fe16N2 is not proposed, analysed, and investigated in any electrical generator. In this context, Fe16N2 is proposed in a linear generator as PM for producing adequate magnetic flux. For analysis and testing the performance of the proposed material, a PMLG is designed. The performances are compared for using Fe16N2 and AlNiCo PMs in the same PMLG design for a fair comparison. It is considered that the proposed PMLG is connected to a direct drive power take‐off system. Simulation results show that the proposed PMLG having Fe16N2 generates 55% more electrical power than that of using AlNiCo. The voltage, current, magnetic flux linkage, power, and magnetic flux density of the proposed PMLG are investigated extensively and compared with those of AlNiCo. The finite element method is applied in the ANSYS/Maxwell software environment for testing the PMLG with the conventional and the proposed PMs as well as results are presented. The proposed design is also validated with a small laboratory prototype. [ABSTRACT FROM AUTHOR]

A key drawback of multirotor unmanned aerial vehicles (UAVs) with energy sources based solely on electrochemical batteries is related to the available on-board energy. Flight autonomy is typically limited to 15–30 min, with a flight duration upper limit of 90 min currently being achieved by high-performance battery-powered multirotor UAVs. Therefore, propulsion systems that utilize two or more different energy sources (hybrid power systems) may be considered as an alternative in order to increase the flight duration while retaining key performance benefits of battery energy storage use. The research presented in this work considers a multirotor UAV power unit, based on the internal combustion engine (ICE) powering an electricity generator (EG) connected to the common direct current (DC) bus in parallel with the lithium-polymer (LiPo) battery, and the respective modeling and identification of individual power unit subsystem, along with the dedicated control system design. Experimental verification of the proposed hybrid power unit control system has been carried out on the custom-build power unit prototype. The results show that the proposed control system combines the two power sources in a straightforward and effective way, with subsequent analysis showing that a two-fold energy density increase can be achieved with a hybrid energy source, consequently making it possible to achieve higher flight autonomy of the prospective multirotor (hover load around 1000–1400 W) equipped with such a hybrid system.

The paper presents a detailed analysis of the dynamics and control of air turbines and electrical generators in oscillating-water-columns (OWCs). The aim is to explain the performance of an OWC device based on the physical behaviour of each system component. The Mutriku wave power plant was chosen as the test case. The power plant is a breakwater located in the Bay of Biscay, in Basque Country, Spain. The contributions of the work are: i) development of a hydrodynamic model of the power plant in the frequency domain; ii) implementation of a non-linear time-domain wave-to-wire model; iii) real-valued implementation of the Prony method for the computation of the wave-radiation force; iv) a detailed generator model based on experimental data to assess the influence of the generator efficiency on the power take-off performance; v) a critical performance comparison of the Wells and biradial turbines; vi) a sensitivity analysis of the control parameters of the turbine/generator set; and vii) an explanation of the comparative performance of both turbines based on statistical data. The turbine performance curves were taken from developers' published experimental data. The results were obtained with a simplified model of the wave climate off the Mutriku test site comprising 14 sea states. • Non-linear time-domain wave-to-wire model of the Mutriku OWC-breakwater was developed. • Experimental electrical generator efficiency was mapped versus rotational speed and shaft torque. • The performances of Wells and biradial turbines were compared based on statistical data. • A sensitivity analysis of the control parameters of the turbine/generator sets was performed. • The biradial turbine was found to be more efficient and less sensitive to the control parameters. [ABSTRACT FROM AUTHOR]

Wave and tidal energies are some of the most prominent potential sources of renewable energy. Presently, these energy sources are not being utilized to their maximum extent. In this paper, we present a new conversion mechanism with an innovative electrical energy converter design that enables the use of wave energy to its maximum potential. The conventional wave energy converter comprises two stages of conversion (kinetic to mechanical and mechanical to electrical), imposing transformation loss that reduces the overall system efficiency. Additionally, the architecture and operational norms are dependent on the availability of shoreline areas, and the convertor is not suitable for all ocean weather conditions. To solve these problems, we have developed a wave energy conversion system that integrates the two stages of power with the minimum number of moving parts. This results in significant reduction of transformation losses that otherwise occur in the process. This paper presents an innovative idea of designing a DC generator that reduces the hierarchy of power conversion levels involved to improve the efficiency. The back and forth motion of the machine means it operates in a two-quadrant generation mode. The machine was constructed as a square box model with windings placed on both the top and bottom stator plates, and the rotor consisted of a field winding placed between these plates with two axes of operation. The electromagnetic field (EMF) induced in the stator plates is due to the resulting flux cutting, which is generated by a rolling object (rotor) in between them. A finite element analysis (FEA) of the machine is also listed to validate the flux linkage and operational efficiency. Additionally, a generator is fabricated to the predetermined design criteria as a proof of concept and the corresponding results are posted in the paper. Additionally, we present the material and cost limitations of this invention and outline some possible future directions.

The commercial electrification of marine vessels started in the 1880s with a direct current (dc) system onboard SS Columbia. However, the popularity of the ac electrical distribution system resulted in the move towards an alternating current (ac) system onboard marine vessels. At present, there are marine vessels that operate based on a diesel-electric system. The on-board diesel engines generate ac power to a common ac bus, from which the electrical propulsion drives source their electrical power. Recently, there is an interest in a shift back to a dc-based diesel-electric system for marine vessels, due to the potential improvement in electrical performance and fuel savings. This paper evaluates the improvement obtained by moving to a dc system for marine vessels in terms of electrical performance and generator scheduling. An overview of a typical ac electrical system currently in use is provided, and modification of the system to a dc-based system is presented. The issue of multiple generator synchronization and harmonic elimination are also discussed. A discussion on the potential benefits of a shift to a dc system is provided, as well as the potential challenges that may arise. Both symmetrical and asymmetrical generator scheduling are examined and the potential fuel savings for an example vessel is calculated. [ABSTRACT FROM AUTHOR]

An airborne vertical axis wind turbine (VAWT) is a new approach in wind turbine development. In this paper, a new design of the airborne VAWT which can produce electricity for a light-emitting diode (LED) system is exhibited. A gas balloon is used as the turbine and features a special blade design to convert wind energy into rotation of the electrical generator. The turbine was designed to meet the characteristics of wind in limited terrestrial wind speed areas. The generator was designed to be lightweight whilst retaining favorable performance for electricity generation. Performance test results showed that the developed generator could provide the required power supply for a LED system. Moreover, the generator can also recharge the batteries used as a voltage regulator for the LED system. [ABSTRACT FROM AUTHOR]

This paper presents the evaluation of the effectiveness of the power supply system of perspective aircrafts, in which all the electrical generators are integrated into the shafts of the main aircraft engine and into the gearless auxiliary power unit. In addition, this paper presents the development of the requirements of integrated electrical generators. The results of the calculation and analysis of the electrical generators for integration on the gearless auxiliary power unit, the high-pressure compressor shaft and the low-pressure compressor shaft of the main aircraft engine are presented. After analyzing the weight and size of the aircraft with integrated electrical generators, the obtained results and the data for Boeing 787have been compared. In the proposed concept, the total mass of electrical machines is less than the total mass of electrical machines of Boeing 787. [ABSTRACT FROM AUTHOR]

This paper presents the development of a portable thermogenerator designed to work on uncontrolled heat sources. Its thermal behavior regarding both steady-state and transient regimens was analytically described and numerically solved by using a lumped capacity model. The ranges of heating power and power increasing rates have been determined to ensure safe operation, or give users advance warning in case of failure. In addition, this model is a useful tool for designing a controller system based on which a feasible thermogenerator can be developed. Experimental tests performed on a prototype based on a commercial BiTe module have demonstrated this goal. [ABSTRACT FROM AUTHOR]

With an increasing number of wind turbines being erected offshore, there is a need for cost-effective, predictive, and proactive maintenance. A large fraction of wind turbine downtime is due to bearing failures, particularly in the generator and gearbox. One way of assessing impending problems is to install vibration sensors in key positions on these subassemblies. Such equipment can be costly and requires sophisticated software for analysis of the data. An alternative approach, which does not require extra sensors, is investigated in this paper. This involves monitoring the power output of a variable-speed wind turbine generator and processing the data using a wavelet in order to extract the strength of particular frequency components, characteristic of faults. This has been done for doubly fed induction generators (DFIGs), commonly used in modern variable-speed wind turbines. The technique is first validated on a test rig under controlled fault conditions and then is applied to two operational wind turbine DFIGs where generator shaft misalignment was detected. For one of these turbines, the technique detected a problem 3 months before a bearing failure was recorded. [ABSTRACT FROM AUTHOR]

A key drawback of multirotor unmanned aerial vehicles (UAVs) with energy sources based solely on electrochemical batteries is related to the available on-board energy. Flight autonomy is typically limited to 15–30 min, with a flight duration upper limit of 90 min currently being achieved by high-performance battery-powered multirotor UAVs. Therefore, propulsion systems that utilize two or more different energy sources (hybrid power systems) may be considered as an alternative in order to increase the flight duration while retaining key performance benefits of battery energy storage use. The research presented in this work considers a multirotor UAV power unit, based on the internal combustion engine (ICE) powering an electricity generator (EG) connected to the common direct current (DC) bus in parallel with the lithium-polymer (LiPo) battery, and the respective modeling and identification of individual power unit subsystem, along with the dedicated control system design. Experimental verification of the proposed hybrid power unit control system has been carried out on the custom-build power unit prototype. The results show that the proposed control system combines the two power sources in a straightforward and effective way, with subsequent analysis showing that a two-fold energy density increase can be achieved with a hybrid energy source, consequently making it possible to achieve higher flight autonomy of the prospective multirotor (hover load around 1000–1400 W) equipped with such a hybrid system. [ABSTRACT FROM AUTHOR]

A complete inductively coupled radio-frequency plasma installation is modeled. This installation includes an electrical generator coupled with a cylindrical inductor containing the plasma. The mathematical modeling of the generator with its triode uses a state space approach. A Runge-Kutta method is used to solve these differential equations. The electromagnetic equation of the inductor is solved by the moment method, whereas the electromagnetic equation of the plasma is solved by the finite difference method. The thermal equation of the argon plasma is solved by the control volume method. The simulations allow us to study the influence of the installation components on voltages, currents, dissipated powers and generator performances. [ABSTRACT FROM PUBLISHER]