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.
A modular UPS system is generally presented as having a much higher level of availability than a monolithic, double conversion, on-line UPS system. However, there are different types of modular UPS systems available on the market, with varying degrees of reliability and availability. To represent the strengths and weaknesses of each architecture and accurately compare them to one another, a detailed...
This paper proposes an adaptive power management strategy with reduced sensor requirement for grid connected hybrid microgrid system under faulty conditions which occur in grid tied converters. Generally parallel combination of grid tied converters (GTCs) are used as an interface between microgrid and grid, which are responsible for power transfer among renewable energy sources (RES), hybrid energy...
Electrical energy obtained from state-owned electricity company is often can not fulfill the electrical energy required by the industry during peak load. Another problem that industry faced is the availability of electrical energy supply is not continuous. Solution to this problem, the industry needs another source of electrical energy so the availability of electrical energy can be achieved. This...
In this paper, an autonomous communication-based centralized control for DC microgrids (MG) has been developed and implemented. The proposed controller enables smooth transition between various operating modes. Finite state machine (FSM) has been used to mathematically describe the various operating modes (states), and events that may lead to mode changes (transitions). Therefore, the developed centralized...
The integration of Battery Energy Storage Systems (BESS) into the power grids has been proposed as an effective solution for mitigating voltage and frequency instability problems arising from the integration of renewable resources with intermittent patterns. One of the most important applications of BESS is to restore an electric power system to operation without counting on the external transmission...
This paper presents the results of a system analysis of different options for electric inverters for the traction drive of an electrical helicopter. The article explains the optimal choice, in terms of the design requirements and future operation conditions, and the type and topology of electric inverter, to supply the traction permanent magnet synchronous motor from the batteries. The main focus...
Fuel cells in aircraft applications are gaining more and more interest because of higher possible efficiency and increasing air pollution standards. A necessary supplement is an efficient, lightweight and reliable DC/DC-converter to adjust the weak fuel cell characteristic to the voltage level of buffer batteries and drive inverters. Cosmic radiation, condensation, strict EMIlimits and significantly...
This paper describes the structure, control and performance analysis of an alternative configuration of a low cost three-phase transformerless online UPS. The proposed UPS avoids the use of galvanic isolation and consists of a half-bridge rectifier, a battery bank, a half-bridge inverter, a split DC bus and an auxiliary circuit. The auxiliary circuit is composed of an inductor and a small rating switching...
Reliability is an essential role in electricity business as the demand is rising rapidly. Recently, Microgrid technologies have been implemented in the traditional centralized grid in order to mitigate the power disturbance. Many researchers have proposed different configurations of the Microgrid with a constitution of renewable energy sources such as Photovoltaic Plant, Wind Plant and back up supply...
In this paper a simple methodology for solar photovoltaic system design based on annual mean Global Solar Radiation (GSR) is presented. The approach involves sizing of the array and the battery for average GSR of the year. The battery bank is sized to operate the load with variable sequence of below average GSR days. This will mean that on the average the battery will be probably charged during rest...
A coordinated secondary control based on a novel autonomous currents sharing control strategy for balanced discharge rate of energy storage systems in islanded microgrid (MG) is proposed in this paper. The coordinated secondary controller is able to regulate the output power of distributed generating (DG) systems according to their state-of-charge by adjusting the virtual resistances of their voltage...
Electrical power supply to serve critical facilities are of high importance in today's world. Instead of building a large electric power system, an intelligent Micro Grid (MG) can be considered as a promising power supply alternative for those critical facilities. This study presents the development and controlling of a laboratory scale MG which consists of several Distributed Energy Resources (DERs)...
Stand-alone PV systems are increasingly being used in rural areas to drive basic loads typically less than 300 VA. Such systems are beneficial where grid electricity is unreliable or not present at all. A 250 VA battery integrated stand-alone PV system is proposed here. This PV system is based on simple hardware structure. It is possible to design this system at lower cost with higher reliability...
For a residential PV installed application complete utilization of battery banks is key to reduce grid dependency and improved reliability. To achieve this objective it's important to keep battery banks at nearly equal state of charges. This paper proposes a technique to keep battery banks within limit by switching isolated panels. Selection of isolated panels is done by considering irregularity of...
In many low-income settings and geographies it's not immediately feasible to deploy central power generation with electric grids. In this context, off-grid approaches like solar home systems (SHS) are gaining wide acceptance. Since battery storage costs are the dominant costs, the value proposition of using a novel mini-grid with shared generation/ storage as opposed to SHS is examined. The relative...
A four switch, low power, battery integrated, photovoltaic stand-alone inverter system is proposed in this paper. The proposed topology is derived by combining a DC-DC bidirectional converter with a Ćuk based inverter. The derived topology has a simple structure consisting of four switching devices and an isolation transformer. A simple integrated control strategy for maximum power point tracking...
System efficiency together with the reliability are the most critical factors in the design, characterization and operation of Electric and Hybrid Vehicles. This paper summarizes those aspects from the system level down to the component details and shows practical methods for evaluation and improvement. This paper concentrates on a small to medium size personal vehicles in electric vehicle (EV) and...
At PUES Corporation we have developed an electric drive system suitable for small vehicles and motorcycles that transports heavy loads. The replacement of the energy sources from fossil fuels reduces the greenhouse gases. The key point in this development is the expandability to be used for a wide range of applications, in order to make effective cost reductions through mass production. The developed...
The reliability prediction of hybrid vehicles is of paramount importance for planning, design, control and operation management of vehicles, since it can provide an objective criterion for comparative evaluation of various structures and topologies and can be used as an effective tool to improve the design and control of vehicles. This paper presents a load-dependent simulation model based on MATALAB...
Electricity is the driving force in a country's economy and the developing world needs reliable low cost electricity for its rapid growth. In light of the challenges faced by these countries, we have proposed a low cost PV based back-up system for critical loads in low grid reliability regions. In addition, the system can also be used in remote places where no access to grid is available. The proposed...
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.