Technisch-wirtschaftliche Aspekte für dezentrale Energieversorgung im Niederspannungsnetz

The development of regenerative technologies, e. g. wind-, biomasses-, solar-energy and fuel cells will change the energy-consumption-structure in the next few years. Especially photovoltaic and small fuel cell systems will be connected to the low-voltage-network. In addition to economic aspects, the technical supply conditions are being researched, e. g. the grid-capacity and the needed protective units. At the end, an energy management system, which handles all special requests caused by decentralized energy conversion systems, will be presented.     

Ad Hoc与蜂窝网络融合技术的讨论

蜂窝网络和AdHoc网络是两种不同结构的网络,前者是有中心的集中式网络结构,而后者是无中心的网络结构。为了有效地提高蜂窝网络的数据传输容量并改善网络覆盖,国外学者提出在蜂窝网络中引入AdHoc中继节点。分析了蜂窝网络和AdHoc网络各自的优缺点,二者融合带来的优势;并介绍了两种蜂窝网中引入AdHoc中继节点的实现方案,最后提出了融合网络中的重点和难点问题,对今后的研究具有一定的启示作用。     

Einfluss von dezentralen Energieversorgungssystemen auf elektrische Verteilnetze

The development of decentralized energy conversion systems and new conditions in the energy economy will cause consequences for the electrical distribution networks. The energy supply system will change from a horizontal one to a mixed structure with many distributed energy supply systems. In this paper the technical supply conditions and a procedure to determine economic aspects for planning and operating electrical distribution networks will be described.     

Der Einfluss dezentraler Erzeugung auf die Verteilnetze

In the course of liberalization, decentralized power producers will increase their infeed into the distribution networks more and more. The impact of the new system components has to be analyzed to achieve the most advantageous application regarding economy and power quality. New simulation models of the dynamic and static behaviour of renewable energy sources, storage units, network couplers and cogeneration of heat and power are used for the analysis of two pilot networks with decentralized power generation.     

Dynamic model of decentralized systems with informationalconnection

This paper presents a design method of decentralized systems with informational connection. The informational connection in this paper denotes an event link which establishes a signal links among physical controlled plants via a communication network. A dynamic transition of an informational connection among decentralized systems is considered and the mathematical structures are discussed using a concept of eigenvalues and eigen-connections over the Galois field GF(2). The global system has variable-structure characteristics due to the transition of informational connection. Examples of decentralized variable-structure systems are shown. In industry, there are many engineering systems that have a dynamic transition of an informational connection. The mathematical model would be useful for analysis and synthesis of various informationally connected systems     

Hybrid Solid Oxide Fuel Cell and Thermoelectric Generator for Maximum Power Output in Micro-CHP Systems

One of the most obvious early market applications for thermoelectric generators (TEG) is decentralized micro combined heat and power (CHP) installations of 0.5 kWe to 5 kWe based on fuel cell technology. Through the use of TEG technology for waste heat recovery it is possible to increase the electricity production in micro-CHP systems by more than 15%, corresponding to system electrical efficiency increases of some 4 to 5 percentage points. This will make fuel cell-based micro-CHP systems very competitive and profitable and will also open opportunities in a number of other potential business and market segments which are not yet quantified. This paper quantifies a micro-CHP system based on a solid oxide fuel cell (SOFC) and a high-performance TE generator. Based on a 3 kW fuel input, the hybrid SOFC implementation boosts electrical output from 945 W to 1085 W, with 1794 W available for heating purposes.     

Planung von dezentralen Querverbundsystemen

Decentralized power supply stations have been developed further in the last 10 years. There is a trend to smaller units and they must be able to compete with large-scaled power plants, which typically have high efficiency and small energy production costs. Especially fuel cells, which can be used as combined heat and power production systems, are expected to be a reasonable decentralized energy supply possibility for small units. Therefore an appropriate gas supply system must be planned and there will be a cross-connection to the electric power supply. In this paper the analogies of planning of these two energy supply systems will be described.     

Stabilization of Interconnected Discrete Systems with Quantization and Overflow Nonlinearities

In this paper, we address the problem of decentralized feedback control design for a class of linear interconnected discrete-time systems subject to quantization and overflow nonlinearities and unknown-but-bounded couplings. A decentralized quantized state feedback controller is designed at the subsystem level to render the closed-loop system asymptotically stable. When the local output measurements are available, a decentralized output-feedback quantized controller is developed attain similar asymptotic stability and guaranteed performance of the closed-loop quantized system. Several special cases of interest are derived and simulation results are provided.     

An anticipatory approach to quantify energetics of recycling CdTe photovoltaic systems

Rapid growth in worldwide photovoltaic (PV) systems will soon result in a massive installed base of modules, electrical systems (ES), and balance of systems (BOS) that are expected to reach their end of life after two or three decades of operation. While existing recycling technologies will likely be available for steel, copper, aluminum, and other commodity materials found in the ES and BOS, these have yet to be accounted for in studies that assess the environmental impacts of PV recycling. More problematic is the lack of research identifying strategies to improve recovery of semiconductor and other module materials and develop recycling infrastructure to minimize energy required to transport these materials. The current leader in photovoltaics recycling is First Solar, which operates facilities for processing prompt scrap, breakage, and any end‐of‐life CdTe PV modules. This paper presents a comprehensive energy assessment of recycling the entire CdTe PV system based on First Solar's processes and identifies hotspots that present opportunities to improve the energy balance of future recycling operations. The energy savings derived from recycling a CdTe PV system reduces the lifecycle energy footprint by approximately 24% of the energy required to manufacture the PV system. By contrast, recycling just the CdTe PV module without the BOS has an approximately neutral net energy impact, recovering 13.2 kg of glass, 0.007 kg of Cd, and 0.008 kg of Te per m². Hotspot analysis shows that reducing the energy required to recover unrefined semiconductor material from the module and ensuring high recovery of steel and glass from the end‐of‐life CdTe PV system will have the greatest impact on the energy benefits of recycling. Also, transportation energy depends on the energy tradeoff between (i) material recovery and recycling operations at the decentralized location, and (ii) transporting, recovering, and recycling the PV system components at a centralized location. An optimal strategy (centralized versus decentralized) is presented to minimize the net energy footprint when distance to the centralized recycling facility and the recycling energy requirements at the decentralized recycling facility are varied. Copyright © 2015 John Wiley & Sons, Ltd.     

Design of a decentralized modular architecture for flexible and extensible production systems

In the European manufacturing industry, production batches are decreasing, resulting in an increase in required changeovers. Companies are pushed to respond quickly and cost-efficient to changing markets. One way for Small and Medium sized Enterprises (SMEs) to become more agile, is to incorporate industrial robots in their production processes; larger enterprises already use this versatile piece of equipment for large batch sizes. To do so, a new perspective and approach is required, tailored to dynamic manufacturing systems in which production systems and components can be easily reconfigured, altered, swapped or replaced. A modular system architecture was developed within project SInBot upon which challenges in dynamic cooperation between robots and humans were projected. The developed system uses decentralized control and distributed intelligence, linked through an extensible, flexible, and fault-tolerant communication architecture. The rapidly growing complexity of traditional systems is compared to its decentralized counterpart to illustrate some of the many advantages of this new system architecture. A manufacturing scenario analogue is discussed and the approach to verify the performance of inner-system components, as well as the benefits of this approach. Key challenges that are encountered in implementing the cooperation into the current industrial environments are identified and projected upon the verification system.     

一类非线性互联系统的H∞模型参考跟踪分散输出反馈模糊控制

本文对一类不确定状态不可测非线性互联系统,给出了一种基于观测器的H_∞模型参考跟踪分散输出反馈模糊控制方法.设计中,首先采用模糊不确定T-S模型对非线性互联系统进行模糊建模,在此基础上,给出模糊分散观测器的H_∞设计和基于观测器的模型参考跟踪分散模糊控制的设计.应用李亚普诺夫和线性矩阵不等式方法给出了模糊分散系统稳定的充分条件.仿真结果进一步验证了所提出的模糊分散控制方法的有效性.     

Cooperative Decision-Making in Decentralized Multiple-Robot Systems: The Best-of-N Problem

Multiple-robot systems (MRS) that are decentrally organized have many benefits over centralized systems. Decentralized systems are less affected by computational and communicative bottlenecks, and they are more robust to the loss of individual member robots. System-level cognitive operations, though, are much more difficult to implement in decentralized systems. One example is the best-of-N decision-making problem, in which a team attempts to unanimously select a single alternative from a list that maximizes a given metric. This is a valuable operation, since many system-level operations can be expressed in this form. Optimal best-of-N decision-making, however, is intractable in large decentralized systems. The contribution of this paper is a biologically inspired algorithm that enables a decentralized MRS composed of very simple robots to make good, unanimous decisions. In a series of physical experiments using real robots, the best decision was made at least 80% of the time. In all, 100% of the decisions achieved perfect consensus, which prevented the MRS from becoming fragmented. The decisions are made using anonymous, local communication, with no direct comparisons of the available alternatives by the individual robots.     

A Decentralized Model Reference Adaptive Controller for Large-Scale Systems

A decentralized model reference adaptive controller (MRAC) for a class of large-scale systems with unmatched interconnections is developed in this paper. A novel reference model is proposed for the class of large-scale systems considered and a decentralized, full-state feedback adaptive controller is developed for each subsystem of the large-scale system. It is shown that with the proposed decentralized adaptive controller, the states of the subsystems can asymptotically track the desired reference trajectories. To substantiate the performance of the proposed controller, a large web processing line, which mimics most of the features of an industrial web process line, is considered for experimental study. Extensive experiments were conducted with the proposed decentralized adaptive controller and an often used decentralized industrial proportional-integral (PI) controller. A representative sample of the comparative experimental results is shown and discussed     

OOONEIDA: an open, object-oriented knowledge economy for intelligent industrial automation

Open knowledge economy in intelligent industrial automation (OOONEIDA) is a new initiative for enabling decentralized, reconfigurable industrial control and automation in discrete manufacturing and continuous process systems. The goal of the OOONEIDA project is the creation of the technological infrastructure for a new, open knowledge economy for automation components and automated industrial products. This will be done by further development of the concept of reusable portable software modules (function blocks) and by their application in the time- and cost-effective specification, design, validation, realization, and deployment of intelligent mechatronic components in distributed industrial automation and control systems.     

Decentralized Consensus Based Target Localization in Wireless Sensor Networks

Target localization is an attractive subject for modern systems that utilize different types of distributed sensors for location based services such as navigation, public transport, retail services and so on. Target localization could be performed in both centralized and decentralized manner. Due to drawbacks of centralized systems such as security and reliability issues, decentralized systems are become more desirable. In this paper, we introduce a new decentralized and cooperative target localization algorithm for wireless sensor networks. In cooperative consensus based localization, each sensor knows its own location and estimates the targets position using the ranging techniques such as received signal strength. Then, all nodes cooperate with their neighbours and share their information to reach a consensus on targets location. In our proposed algorithm, we weight the received information of neighbour nodes according to their estimated distance toward the target node. Simulation results confirm that our proposed algorithm is faster, less sensitive to targets location and improves the localization accuracy by 85% in comparison with distributed Gauss–Newton algorithm.     

Optimization of decentralized hybrid electrical energy systems (with photovoltaics) for typical villages in the North Indian plains

This paper presents an analysis of an optimal decentralized mix of photovoltaics, biogas generation and biomass gasifier generation, to meet the electrical energy demand of typical villages in the North Indian plains. the optimal mix preserves existing patterns of fertilizer application and cooking and also corresponds to minimum cost. Survey data for four villages have been used for a numerical appreciation of the results. It is seen that the optimal energy strategy consists of meeting as much demand as possible by biogas generators using dung and meeting the rest of the demand by an optimal combination of biomius gasifier generation and photovoltaics. the cost of electrical energy with such decentralized systems lies between Rs. 2.2 per k Wh and Rs. 8.9 per k Wh for different villages (US $1 = Rs. 30). It is seen that locally availble fuel (dung and agricultural waste) is insufficient for electrical generation and the balance has to be met by photovoltaics. Rising electrical demand in coming years means that pliotovoltaics will be an increasingly important component of such optimal systems.     

FPGA-Based Decentralized Control of Arrayed MEMS for Microrobotic Application

In this paper, the authors have developed and implemented a decentralized decision-making strategy using field-programmable gate array (FPGA) technology as a prototype for an integrated controller of a microelectromechanical systems (MEMS) array for air-flow planar micromanipulation. The MEMS array was proposed to be integrated in a hybrid multichip module containing the FPGA-based controller. Algorithms and architectures, used for the decentralized control implementation and the hardware resource optimization, are described. A charge-coupled device camera was used to make each MEMS like an autonomous system when the distributed MEMS chip was tested. Finally, under air-flow condition, the FPGA-based decentralized control system successfully performed an object manipulation.     

A methodology for the design of distributed search in P2P middleware

Important research efforts are being conducted in the area of search, lookup, and routing, and are even increasing in the quest for P2P middleware that is both scalable and decentralized. To structure and classify current as well as facilitate and give direction to future research, this methodology proposes a top-down two-dimensional design space. This design space has been developed for exhaustiveness so as to cover all possible design options, existing or yet to be conceived. A comprehensive survey of P2P search systems serves as a reference for the reader while at the same time validating the framework. An identification of areas in the design space not covered by current systems leads to the design of a novel peer-to-peer-based keyword routing scheme. Finally, an evaluation of possible design options along the most important requirement will help guide system designers.     

Dezentrale Erzeugungsanlagen und deren Netzintegration

The demand of electricity will further increase with growing rates of at minimum 2%. In Austria the additional demand will in future mainly be generated by thermal power stations with district heating and by regenerative energy resources. The strong fluctuations in generation from wind need to be limited by special measures for balancing energy. Demand Side Management on the consumer side by use of communication technology forms an interesting possibility. Apart from that the remote control of decentralized generation units by forming a virtual power station is of importance.     

Provisioning multimedia wireless networks for better QoS: RRM strategies for 3G W-CDMA

Third-generation mobile communication systems will bring a wide range of new services with different quality of service requirements and will open the ability to exploit radio resource management functions to guarantee a certain target QoS, to maintain the planned coverage area and to offer a high-capacity while using the radio resources in an efficient way. RRM functions impact the overall system efficiency and the operator infrastructure cost, so they will definitively play an important role in a mature 3G scenario. In order to provide some insight into radio resource management (RRM) strategies implementation, a range of representative case-studies with several innovative algorithms are presented and supported by simulation results in a realistic UMTS Terrestrial Radio Access Network scenario as devised in the 3GGP standardization forum. In particular, a decentralized uplink transmission rate selection algorithm in the short term, a congestion control mechanism to cope with overload situations, and downlink scheduling for layered streaming video packets are proposed.