The development of future smart electricity grids is driven by efficiency and climate targets and economic benefit for producers, retailers and customers on the deregulated electricity market. Since most investments will be made by grid owners acting as regulated monopolies, it is unclear how they will get return on their investments. Can demand response programs create cost reductions for the grid owner that help motivate the investment in smart grids? Two cases of cost reduction opportunities are evaluated assuming that peak loads are reduced by a demand response program: optimization of cable dimensions for lower peak loads when building new grids, and avoided investments in reinforced capacity in the existing grid. Potential cost reductions are estimated for the two example cases, using financial and technical data for Fortum's local distribution grid in Stockholm. The result shows that reducing the capacity in the cables by 70-80 % only brings down investment costs by 3-4 %, since the common expense for excavation outweighs the incremental cost of cables. Over-capacity means increased redundancy and flexibility to increase load in the future, which are valuable features for a grid owner.Regarding investments in the existing grid, a substation that needs replacement because of overload is analyzed. Assuming a continued trend of steadily increasing load, a 34 % peak load reduction would delay the investment 20 years, which is in turn worth 900,000 SEK in 2010 prices.

This master thesis was provided by ABB Cooperate Research in Västerås. This study has two major purposes: (1) to identify the characteristics of a flywheel energy storage system (FESS), (2) take the first steps in the development of a simulation model of a FESS. For the first part of this master thesis a literature reviews was conducted with focus on energy storage technologies in general and FESS in particular. The model was developed in the simulation environment PSCAD/EMTDC; with the main purpose to provide working model for future studies of the electrical dynamics of a flywheel energy storage system. The main conclusion of the literature review was that FESS is a promising energy storage solution; up to multiple megawatt scale. However, few large scale installations have so far been built and it is not a mature technology. Therefore further research and development is needed in multiple areas, including high strength composite materials, magnetic bearings and electrical machines. The model was implemented with the necessary control system and tested in a simulation case showing the operational characteristics.

With the world suffering from energy crisis, Smart Grid is the expanding research topic that deals vigorously with the current problems. It promotes decentralized renewable energy generation system, participate many local energy producers to energy market, adds vehicle to grid (V2G), minimize the energy loss in the electrical system, and participate many active consumers to the real market. It is an emerging project that needs an expert from many fields, thus it opens door of opportunities for many people around the globe. The present thesis deals with the communication scenario in smart grid. Communication is the backbone of Smart Grid and the thesis tries to highlight the available communication technologies for smart grid application. The thesis discuss most profitable communication technologies used for this purpose which are power line communication and wireless communication, in which power line communication aspects and characteristics are covered more than wireless communication for its use are seen more in upcoming days. In all the thesis will outline the opportunities and challenges of power line communication and wireless communication for smart grid application.

Recently, there have been many initiatives to incorporate advanced controls, two way communications, digital technologies and advanced power system components in the operation and control of power distribution systems. These initiatives are aiming to realize what becomes known as the “Smart grid”. It is expected that a Smart Grid will lead to enhancement in the reliability and efficiency of the power system. The movement towards the Smart Grid is motivated by many factors; the need to integrate more renewable power to mitigate the global warming, the increasing interest in connecting more distributed generation (DG) as a way to postpone large investment in transmission and bulk generation, and the need to increase the reliability of the power system overall to minimize disturbance costs. It is the overall goal of this research to introduce novel distribution system operation techniques to assist in the effort of realizing the “Smart Distribution System” in both normal and system restoration modes. In particular, three main operation functions are dealt with in this research work; Voltage Control, Reactive Power Control and Distribution System Restoration. First for Voltage Control, a reliable and efficient method is proposed to control voltage regulators in order to enable the regulation of multiple feeders with diversified loads using only one regulator provided that no DG is connected to the feeders. Regulator’s tap is selected based on the solution of an integer linear optimization problem. The method has a closed form solution for the optimal tap; that is valuable for real time operation. In addition, necessary condition for feasible solutions is examined. Next, a novel coordinated voltage control scheme is proposed to enable the voltage regulator to efficiently regulate the voltage of multiple feeders in the presence of DGs. The proposed technique is based on placing a Remote Terminal Unit (RTUs) at each DG and each line capacitor. These RTUs coordinate together, through communication, and form a multi-agent system. An important contribution of this research is that the proposed scheme provides the minimum hardware requirement to efficiently estimate the voltage profile of a feeder with DGs. The proposed scheme enables the integration of more DGs into the system by, efficiently, coordinating the operation of voltage regulators and DGs to mitigate voltage rise problem caused by the connection of DGs to the system. Second, for Reactive Power Control, a decentralized reactive power control scheme is proposed to optimally control switched shunt capacitors of the system in order to minimize system losses and maintain acceptable voltage profile. The proposed algorithm provides capacitors with “Advanced Voltage Sensing” capability to enable capacitors to switch in and out according to the global minimum and maximum voltage of the feeder. The proposed technique utilizes the same RTU used for voltage control and relies on the voltage profile estimation technique proposed in this research for the coordinated voltage control. In addition, novel decentralized algorithm is proposed to estimate the feeder voltage profile change as a result of injecting reactive power at the capacitor bus. The proposed reactive power control scheme can be used to coordinate the operation of any number of capacitors connected to the distribution system. Combining voltage control and reactive power control schemes, generalized coordinated voltage control is proposed to coordinate between DGs, shunt capacitors and voltage regulators in order to achieve optimal voltage control for the distribution system and solve the steady state voltage rise problem caused by the connection of DGs, hence, allowing more DGs to be connected to the system. Over and above, the proposed generalized coordinated voltage control enables the realization of a new operation-time DG connection impact assessment concept. Based on this concept, the system will carry out a real-time assessment and decide, based on the available control actions, the maximum DG power that can be allowed to connect to the system at particular operating conditions. This new concept will allow great flexibility to the connection of DGs, most notably, when, due to a change in system configuration, the DG is needed to be connected to a feeder other than the one it was planned for during the planning stage. The last operation function dealt with in this research work is the distribution system restoration. Novel decentralized distribution system restoration scheme is proposed. The proposed scheme is based on dividing the distribution system into zones based on the availability of disconnecting switches. Each zone is controlled by an Agent. The restoration is done based on the coordination between these Agents. Proposed communication protocols between Agents are discussed in details. The goal of the proposed restoration scheme is to maximize the restored power while preserving the radial structure of the distribution system and without exceeding the thermal limit of any equipment in the system. As the proposed technique does not assume any supervision from any central point, this technique will enable the realization of a self-healing distribution system restoration.

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Organizations nowadays want employees who are flexible, adaptable, autonomous, creative, willing to learn, self-motivated, and able to fit productively into teams to satisfy instable and varied consumer demands. Consequently, job performance no more relies on repetitive and routine tasks which traditionally could be completed and improved by working-hard only. Nevertheless, the economy in the world is becoming dynamic, rapid and unpredictable for sure. Transparently workers will need to unceasingly increase their skill base to experience workplace success in the future. Therefore, management scholars suggest organizations who want to survive or outperform of the time may need to consider traits in addition of conscientiousness when making hiring decisions. The Big Five undoubtedly provides the general and basic consideration of personality. As the environment nowadays changes, not only the Big Five but also more advanced and specific personality constructs for advantageous solutions hitting the mark are needed. Playfulness, defined as a multidimensional personality with curiosity, absorption, sense of humor, manifest joy and childlikeness factors, may be one promising personality which replies the call from the academic and plays as the alternative selection assessment tool for selection to the practical simultaneously. Playfulness has been emphasized in child development, education, and clinical counseling fields for a long time. This personality fosters optimal human function and accompanies intrinsic motivation according to developmental psychology and positive psychology perspectives. Notwithstanding its importance, playfulness in adults does not catch enough attention of the academic. This study first empirically tests relationship between playfulness and job performance (in-role performance, creative performance) and clarifies the discrepancy of style effects on different dimensions of performance which may better explain the phenomena in the workplace. Second, this study moves a step forward to propose a personality construct from developmental psychology triangle especially favorable to selection consideration. Third, through the lens of working behavior style, the results of this study also better explain the mechanism link playfulness and performance that throw light on training direction for people in organizations already. By defining working-smart/hard as behavioral style instead of ability and motivation, this study opens a new avenue for research to discuss the issue thoroughly. Future research suggestions and practical applications are also provided.

In recent years, due to the issues of energy saving, the smart grid has become more important. AMI (Advanced Metering Infrastructure) is the basic of smart grid. However, AMI¡¦s network initialization usually cost a lot of time delay and energy waste because of many collisions due to the initialization in the high node density and variable network. In this paper, we proposed a Dynamic Contention Slot Initialization Protocol (DCSI Protocol) to reduce time delay and energy waste in the network initialization. At the beginning, all nodes in DCSI protocol are set in the receiving state. The proposed approach reduces not only collisions but also the communication failure due to the interference out of the transmission range. We divided time into time slots and then composed them to superframe. The first slot of superframe is designed for master node¡¦s broadcast, and other time slots are devised for other nodes to join in the network. Based on the previous superframe, nodes for the proposed protocol adjust the number of the contention slot by detecting collisions to adapt the high node density and variable network. The simulation results demonstrate superiority of DCSI protocol over flooding.

The problem of liquid loading is common for all gas producing wells and should be identified and solved for efficient gas production. Production engineers and operators need to choose the best solution possible, one that is cost effective and also efficient in doing the job. The plunger lift operation is a cost-effective solution to this liquid loading problem and also is efficient in increasing the gas production. However, the current understanding of plunger lift operation has used field experience and some previous models that have restrictive assumptions which might not be applicable for all plunger lift installations. This research proposes a new plunger lift model that overcomes some of the limiting assumptions of earlier models by using additional data available in the form of pressure and temperature from new technology like smart plunger. The model is based on fundamental principles of mass conservation and pressure balance, and uses the smart plunger data as input. The implementation of the model is carried out in user-friendly and easily accessible software like Excel VBA (Visual Basic Applications). The model predicts the plunger velocity, plunger position and annulus liquid level during an upward travel of the plunger in an onshore gas well in East Texas. The results of model implementation in VBA show the importance of fluid properties for the model, apart from indicating that the model is optimized for the given set of input data. The model developed in this research considers only pressure drop due to gravitational effects, and thus provides a scope for improvement in modeling the plunger lift dynamics by adding frictional and acceleration components. This research also provides recommendations for future work that can be carried out on plunger lift modeling using smart plungers.

Smart Grid technology is likely to be implemented in various magnitudes across utilities in the near future. To accommodate these technologies significant changes will have to be incorporated in building design construction and planning. This research paper attempts to evaluate public utility executives’ plans to adopt smart grid technologies and to assess timing of smart grid impacts on future design and construction practices. Telephone survey was the data collection method used to collect information from executives at cooperative and municipal utilities. The study focuses on small and medium utilities with more than five thousand customers and fewer than one hundred thousand customers. A stratified random sampling approach was applied and sample results for fifty-nine survey responses were used to predict the timing of smart grid implementation and the timing of smart grid impacts on future design and construction practices. Results of this research indicate that design and construction professionals should already be developing knowledge and experience to accommodate smart grid impacts on the built environment.

Wireless communication systems are limited in performance and capacity by the major impairments of multipath fading and co-channel interference. Smart antenna can combat the impairments, thereby enhancing the system capacity and alleviating the problem of bandwidth limitation. In general, there are two main types of smart antennas; these are switched beam systems and adaptive array systems. An antenna array, which consists of a group of several antenna elements and digital signal processing units, can form several independent beams in different angles. Smart antennas aim the main beam in the direction of the target mobile user and locate the nulls in the direction of the interfering signals from other mobile users to enhance the signal-to-interference power ratio and system capacity. One of the most important parts in adaptive array antenna systems is the adaptive algorithm to adjust the weights of an array. These algorithms include unconstrained as well as constrained LMS, normalized LMS, structured gradient, RLS, CMA, and conjugate gradient method. In this thesis, we propose a new algorithm based on weight-partition RLS method to reduce the computational complexity. The major concept of our algorithm is decreasing the dimension size of data matrix. Performance and complexity of the proposed algorithm is evaluated and compared with traditional WRLS algorithm.