The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Through this project, successful applicants from Korea and China will be accepted into the Graduate School of Engineering Master's Course, that was established in April 2011, at Nagasaki University. They will be trained to become highly skilled professionals with practical knowledge who can contribute to solving water environment conservation issues, including sustainable water use, in East Asia.
In this study, parallel connection of separate voltage sources has been realized using cuk converters. For this aim, output voltages of converters are measured continuously and then fixed to a reference value. The PWM signals which are required to control the converters and to sense the current and voltage signals are generated by an FPGA. Since the FPGA has parallel processing feature, voltage and...
This paper presents a single phase inverter for the use of transformer-linked interleaved flyback converter. Compared with the core size of conventional type and proposed type flyback converter, the compact and light weight performance of the core are realizable. The power conversion system to propose comprises a flyback converter and a single phase inverter. Since the smoothing capacitor between...
An islanding situation should be detected accurately soon after the island is formed. Because failure to trip the islanded distributed resource can lead to a number of problems for the resource and the connected load. Therefore, it is important to distinguish islanding and non-islanding situations and block the nuisance tripping effectively. This paper compares two islanding detection methods, during...
Utility companies have been seeking methods to operate electricity distribution infrastructures efficiently. Smart grid applications provide opportunities to network operators to collect data from consumers. Therefore operators could track power consumption based on historical and immediate data. Thanks to remotely collecting data, operators take necessary action to manage changes in consumption rate...
With regard to spatial-planning aspects, the following can be said: analysis of the legal regulation and contacts established with government's institutions brought to the conclusion that spatial-planning requirements represent the most restrictive limitations for small hydropower plants construction. It should be particularly stressed that these requirements differ from one location to another, so...
The aim of this paper is to analyze dynamics of isolated electrical grid during short term interruptions. The effect of short term interruptions of the power supply on the characteristic values of synchronous generator in autonomous operation is analyzed. Dynamical loads (two induction motors), are connecting to the grid. Short-term interruptions that occur in different moments allow analyze of this...
This paper deals with the power efficiency improvement of the composite resonant DC-DC converter, which is developed to be applied to the power conditioner of the photovoltaic generation system. To improve the power efficiency, following three approaches are taken: 1) optimum design of the transformer 2) use of the voltage doubler rectifier. 3) reduction of the winding loss of the transformer. The...
Decarbonisation policies adopted worldwide are leading to an increasing deployment of renewable energy sources. In Europe, the growing number of offshore wind farm projects calls for scrutinising merits and opportunities of their interconnection via multi-terminal links rather than conventional point-to-point connections. The semiconductor components used in the converters and the resistance of power...
By applying new technologies of energy and DC distribution technology, the smart-grid based digital load device is increased. Due to the power conversion technology, the power consumption is minimized, maximize the utilization of self-development self-energy power consumption. Derive optimum efficiency power structure, and at the same time, the existing AC system with high quality bi-directional AC-DC...
Wind power has received much attention as the most widely used type of renewable energy because of its higher energy conversion efficiency than solar power. In addition to the large wind power turbines already in operation, small wind power turbines are also being developed to meet their increased demand in urban or rural areas. However, the efficiency of current operating small wind power turbines...
Al loaded CaO catalysts for biodiesel synthesis were prepared with alkali co-precipitation method and investigated. The catalytic activities were examined with transesterification of triolein to oleic methyl ester (OME) as model reaction of biodiesel formation. The catalytic activity of these catalysts strongly depends on the amount of Al loading and formation of composite oxide phase on catalyst...
In this study, using concentrated solar energy more efficiently by spectral decomposition approach is introduced. The theoretical analysis is presented for decomposed as spectral concentrated solar radiation and then the potential utility of the system is discussed.
This paper introduced a fault localization method in DC Marine power system using multiple injection at two different locations. The experimental test results which were derived from the DC Marine system demonstrator show that the fault can be detected and located quickly and accurately. Accompany with the circuit breaker and the Bus Interface Unit (BIU), the load supply can be uninterrupted during...
This paper presents a novel magnetic circuit model incorporating micromagnetic simulation. The proposed magnetic circuit model consists of two elements; one is a dc hysteresis element given by the micromagnetic simulation, the other is an inductance element which denotes eddy current loss in silicon steels. In addition, the proposed model can be coupled with an external electric circuit model. The...
This paper presents a novel flux barrier type outer rotor interior permanent magnet (IPM) motor which has both rare-earth and ferrite magnets. The proposed IPM motor has two air layers in the outer rotor. The rare-earth magnets are inserted into the first layer, while the ferrite magnets are placed into the second one. The torque performance of the proposed IPM motor is larger than that of the conventional...
Nowadays, there are several difficulties are met in the selection of appropriate conditions, place of use, and purpose of photovoltaic (PV) systems. The reason is that electrical power output of PV system shows a non-linear variation, unlike other applications, depending on the internal resistance of electrical devices (loads) as well as radiation intensity and environmental temperature. Therefore,...
Solar radiation prediction has a great importance in electricity generation from solar energy and helps to size photovoltaic power systems. Therefore, the solar radiation parameter was predicted at 10-min intervals in this study. Outside temperature, outside humidity and barometric pressure parameters were used as meteorological input variables by the developed k-nearest neighbor (k-NN) classifier...
A solar cell or photovoltaic cell is a device which generates electricity directly from visible light. However, the Gratzel solar cells' efficiency is fairly low. So, it costs expensive according to other energy resources products. There is several factors affect gratzel solar cell efficiency which formed from chlorophyll. This research work is a comparative study between Grätzel chlorophyll solar...
In this study, an experimental application has been improved for three phase synchronous motor including observation and control the motor speed by adjusting the frequency. A DAQ (Data Acquisition Card) has been used in the system as controller. Interface program has been prepared in Visual C#.NET platform which has more visual components and provides data exchange safely. Thanks to this interface...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.