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Podnikatelský plán vytvoření distribuční sítě společnosti Porcelanosa v České republice / Business plan of building distribution network for company Porcelanosa in the Czech RepublicPrade, Lukáš January 2017 (has links)
The aim of this thesis is to create a business plan for an existing company Design Bath, which operates as a wholesale and exclusive distributor of company PORCELANOSA Grupo on the Czech market of ceramic tiles. The plan is focused on building and extending current distribution network of PORCELANOSA Grupo products and should serve as a background for future decision making process and development of long-term strategy of company Design Bath. On the basis of this business plan we should be able to evaluate its feasibility. The theoretical part of this thesis contains basic introduction into business plans from theoretical point of view and market research methodology. The practical part includes the description of international and Czech market of ceramic tiles in order to understand the business opportunity. Description of competition, market research, proposal of suitable forms of distribution and financial plan are all included in the practical part in the way that the chapters logically follow each other. Financial plan revealed that the business plan is viable. Potential risks and conditions of successful realization complete the last part of the thesis.
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Equivalent dynamic model of distribution network with distributed generationMat Zali, Samila Binti January 2012 (has links)
Today’s power systems are based on a centralised system and distribution networks that are considered as passive terminations of transmission networks. The high penetration of Distributed Generation (DG) at the distribution network level has created many challenges for this structure. New tools and simulation approaches are required to address the subject and to quantify the dynamic characteristics of the system. A distribution network or part of it with DG, Active Distribution Network Cell (ADNC), can no longer be considered as passive. An equivalent dynamic model of ADNC is therefore extremely important, as it enables power system operators to quickly estimate the impact of disturbances on the power system’s dynamic behaviour. A dynamic equivalent model works by reducing both the complexity of the distribution network and the computation time required to run a full dynamic simulation. It offers a simple and low-order representation of the system without compromising distribution network dynamic characteristics and behaviour as seen by the external grid. This research aims to develop a dynamic equivalent model for ADNC. It focuses on the development of an equivalent model by exploiting system identification theory, i.e. the grey-box approach. The first part of the thesis gives a comprehensive overview and background of the dynamic equivalent techniques for power systems. The research was inspired by previous work on system identification theory. It further demonstrates the theoretical concept of system identification, system load modelling and the modelling of major types of DG. An equivalent model is developed, guided by the assumed structure of the system. The problem of equivalent model development is then formulated under a system identification framework, and the parameter estimation methodology is proposed. The validation results of the effectiveness and accuracy of the developed model are presented. This includes the estimation of the parameter model using a clustering algorithm to improve the computational performance and the analysis of transformer impedance effects on the ADNC responses. The evaluation of probability density function, eigenvalue analysis and parameter sensitivity analysis for the model parameters are also presented. Typical model parameters for different network topologies and configurations are identified. Finally, the developed equivalent model is used for a large power system application. The accuracy and robustness of the developed equivalent model are demonstrated under small and large disturbance studies for various types of fault and different fault locations.
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Distribution network supports for transmission system reactive power managementChen, Linwei January 2015 (has links)
To mitigate high voltages in transmission systems with low demands, traditional solutions often consider the installation of reactive power compensators. The deployment and tuning of numbers of VAr compensators at various locations may not be cost-effective. This thesis presents an alternative method that utilises existing parallel transformers in distribution networks to provide reactive power supports for transmission systems under low demands. The operation of parallel transformers in small different tap positions, i.e. with staggered taps, can provide a means of absorbing reactive power. The aggregated reactive power absorption from many pairs of parallel transformers could be sufficient to provide voltage support to the upstream transmission network. Network capability studies have been carried out to investigate the reactive power absorption capability through the use of tap stagger. The studies are based on a real UK High Voltage distribution network, and the tap staggering technique has been applied to primary substation transformers. The results confirm that the tap staggering method has the potential to increase the reactive power demand drawn from the transmission grid. This thesis also presents an optimal control method for tap stagger to minimise the introduced network loss as well as the number of tap switching operations involved. A genetic algorithm (GA) based procedure has been developed to solve the optimisation problem. The GA method has been compared with two alternative solution approaches, i.e. the rule-based control scheme and the branch-and-bound algorithm. The results indicate that the GA method is superior to the other two approaches. The economic and technical impacts of the tap staggering technique on the transmission system has been studied. In the economic analysis, the associated costs of applying the tap staggering method have been investigated from the perspective of transmission system operator. The IEEE Reliability Test System has been used to carry out the studies, and the results have been compared with the installation of shunt reactors. In the technical studies, the dynamic impacts of tap staggering or reactor switching on transmission system voltages have been analysed. From the results, the tap staggering technique has more economic advantages than reactors and can reduce voltage damping as well as overshoots during the transient states.
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Coordinated active power reduction strategy for voltage rise mitigation in LV distribution networkAinah, Priye 16 August 2018 (has links)
Integration of renewable energy systems by the utility, customers, and the third party into the electric power system, most especially in the MV and LV distribution networks grew over the last decade due to the liberalization of the electricity market, rising energy demand, and increasing environmental concern. The distributed rooftop PV system contributes to relieve the overall load, reduce losses, avoid conventional generation upgrade, and better matching of demand on the LV distribution network. Originally, the LV distribution network is designed for unidirectional current flow, that is from the substation to customers. However, a high penetration of rooftop solar PVs (with power levels typically ranging from 1 – 10 kW) may lead to the current flowing in the reverse direction and this could result in a sudden voltage rise. These negative impacts on the network have discouraged the distribution network operators (DNOs) to allow increased PV penetration in the LV distribution network because some customers load, and equipment are sensitive to voltage perturbation. Presently, the most applied voltage rise mitigation strategy for high rooftop solar PV penetration is the total disconnect from the LV distribution network when the voltage at the point of common coupling (PCC) goes above statutory voltage limits. However, the sudden disconnection of the PV system from the grid can cause network perturbation and affect the security of the network. This action may also cause voltage instability in the network and can reduce the lifetime of grid equipment such as voltage regulators, air conditioner etc. Due to this negative impact, different voltage rise mitigation strategies such as the active transformer with on load tap changers (OLTC), distributed battery energy storage system and reactive power support (D-STATCOM, etc.) have been used to curtail voltage rise in the distribution network. However, the implementation of D-STATCOM device on a radial LV distribution network results in high line current and losses. This may be detrimental to the distribution network. Therefore, in this thesis, a coordinated active power reduction (CAPR) strategy is proposed using a modified PWM PI current control strategy to ramp down the output power and voltage of a grid-tied voltage source inverter (VSI). In the proposed strategy, a reactive reference is generated based on the measured voltage level at the PCC using a threshold voltage algorithm to regulate the amplitude of the modulating signal to increase the off time of the high frequency signal which shut down the PV array momentary in an extremely short time and allow the VSI to absorb some reactive power through the freewheeling diode and reduce voltage. The proposed CAPR strategy was designed and simulated on a scaled down simple radial LV distribution network in MATLAB®/Simulink® software environment. The results show that the CAPR can ramp down the PV output power, reduce reverse power flow and reduce the sudden voltage rise at the point of common coupling (PCC) within ±5% of the standard voltage limit. The study also compares the performance of the proposed CAPR strategy to that of the distributed static compensator (D-STATCOM) and battery energy storage system (BESS) with respect to response time to curtail sudden voltage rise, losses and reverse power flow. The investigation shows that the D-STATCOM has the faster response time to curtail voltage rise. However, the voltage rise reduction is accompanied by high current, losses and reverse active power flow. The introduction of the BESS demonstrates better performance than the D- STATCOM device in terms of reverse power flow and losses. The CAPR strategy performs better than both D-STATCOM and BESS in terms of line losses and reverse power flow reduction.
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Technická řešení přepojení hladiny VN z 35 kV na 22 kV / Technical proposal of distribution system using 22 kV instead of 35 kVKopunec, Kristián January 2020 (has links)
The diploma thesis deals with the design of the connection of the Svratecko area with the distribution network of the company E.ON Distribuce, a.s.. The theoretical part describes the energy legislation and the individual standards on which the thesis is based. It also describes the concept of a 22 kV high voltage network. The practical part of the thesis is focused on the creation of line models in the program E-vlivy, which will supply the Svratecko area and the model of the monitored area. Outputs from the thesis will be used by E.ON Distribuce, a.s. to evaluate the connection of the Svratecko area.
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Možnosti využití metod vícerozměrné statistické analýzy dat při hodnocení spolehlivosti distribučních sítí / Possibilities of using multi - dimensional statistical analyses methods when evaluating reliability of distribution networksGeschwinder, Lukáš January 2009 (has links)
The aim of this study is evaluation of using multi-dimensional statistical analyses methods as a tool for simulations of reliability of distribution network. Prefered methods are a cluster analysis (CLU) and a principal component analysis (PCA). CLU is used for a division of objects on the basis of their signs and a calculation of the distance between objects into groups whose characteristics should be similar. The readout can reveal a secret structure in data. PCA is used for a location of a structure in signs of multi-dimensional matrix data. Signs present separate quantities describing the given object. PCA uses a dissolution of a primary matrix data to structural and noise matrix data. It concerns the transformation of primary matrix data into new grid system of principal components. New conversion data are called a score. Principal components generating orthogonal system of new position. Distribution network from the aspect of reliability can be characterized by a number of new statistical quantities. Reliability indicators might be: interruption numbers, interruption time. Integral reliability indicators might be: system average interruption frequency index (SAIFI) and system average interruption duration index (SAIDI). In conclusion, there is a comparison of performed SAIFI simulation according to negatively binomial division and provided values from a distribution company. It is performed a test at description of sign dependences and outlet divisions.
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Modelación hidráulica de la red de distribución de agua potable en la localidad de Paucartambo - Cusco / Hydraulic modeling of the drinking water distribution network in the town of Paucartambo- CuscoValenzuela Peña, Mauricio Elias, Orrillo Cruz, Gianmarco Anthony 23 October 2019 (has links)
En la actualidad, la falta de planificación y control que existe en el desarrollo de proyectos de abastecimiento de agua potable es un factor determinante en la presencia de deficiencias en el funcionamiento de las redes de distribución en términos de continuidad y calidad de servicio.
Esta investigación, haciendo uso del modelamiento hidráulico, busca evaluar el comportamiento de la red de distribución de agua de la localidad de Paucartambo-Cusco, con el fin de proponer soluciones y mejoras que ayuden a controlar y disminuir las deficiencias tanto actuales como futuras que pudieran presentarse.
Primeramente, se planteó la modelación de la red en estado actual, comportamiento real, verificando los distintos factores de diseño, así como la consideración del análisis de agua no facturada (ANF).
En este se encontró que las deficiencias del parque de medidores correspondientes a las conexiones activas generan un elevado porcentaje de ANF, lo que afecta el funcionamiento de la red en términos de continuidad y servicio.
Para evaluar su influencia en una red futura se realizó un balance oferta-demanda. Bajo esta premisa se presentó una propuesta de red futura en un escenario donde se controla el porcentaje de ANF mediante la implementación de planes y acciones de manejo, logrando reducir la dotación existente (302.38 lt/hab/dia) hasta valores más acordes con el R.N.E (180 lt/hab/dia) significando una disminución del porcentaje de ANF de 68% hasta 40.47% aproximadamente, lo que garantiza un funcionamiento más óptimo tanto hidráulica como económicamente frente a un escenario que no considere el análisis de ANF. / At present, the lack of planning and control that exists in the development of potable water supply projects is a determining factor in the presence of deficiencies in the operation of distribution networks in terms of continuity and quality of service.
This research, using hydraulic modeling, seeks to evaluate the behavior of the water distribution network of the town of Paucartambo-Cusco, in order to propose solutions and improvements that help control and reduce both current and future deficiencies that could introduce oneself.
First, the modeling of the network in the current state, real behavior, verifying the different design factors, as well as the consideration of the non-invoiced water analysis (ANF) was considered.
In this, it was found that the deficiencies of the meter stock corresponding to the active connections generate a high percentage of ANF, which affects the operation of the network in terms of continuity and service.
To assess its influence on a future network, an offer-demand balance was made. Under this premise, a proposal for a future network was presented in a scenario where the percentage of ANF is controlled through the implementation of management plans and actions, reducing the existing endowment (302.38 lt / hab / day) to values more in line with the RNE (180 lt / hab / day) meaning a decrease in the percentage of ANF from 68% to approximately 40.47%, which guarantees a more optimal operation both hydraulically and economically compared to a scenario that does not consider the ANF analysis. / Tesis
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[pt] A INFLUÊNCIA DO PLANEJAMENTO TRIBUTÁRIO NO DESENHO DA REDE DE DISTRIBUIÇÃO E NA LOCALIZAÇÃO DE CENTROS DE DISTRIBUIÇÃO / [en] THE INFLUENCE OF TAX PLANNING IN THE DISTRIBUTION NETWORK DESIGN AND LOCATION OF DISTRIBUTION CENTERSDANIEL PRADO DO ESPÍRITO SANTO 14 July 2016 (has links)
[pt] A inclusão da gestão tributária no planejamento da cadeia de distribuição é fator diferenciador, especialmente no Brasil, onde os Estados têm políticas tributárias díspares e uma postura agressiva para atrair empresas. A inclusão das preocupações tributárias quando da definição de redes de distribuição, nomeadamente na escolha de localização de infraestruturas, é, no entanto, ainda feito de forma empírica. Para avaliar o impacto dos incentivos fiscais no desenho da rede de distribuição, foi proposto um modelo de programação linear inteira mista (PLIM), incluindo como parâmetros e restrições as oportunidades criadas pela política tributária. O objetivo é definir o número e o local de centros de distribuição, bem como a alocação de clientes a cada centro, tal que o custo logístico seja minimizado (custo de frete, custo de construção, operação e manutenção dos centros de distribuição e custos tributários divididos entre mudanças de alíquotas de produtos e de fretes ao realizar cada transferência de localização). O modelo é aplicado a uma empresa brasileira que comercializa produtos químicos e foi instalada em um local distante do ponto de entrega final dos produtos, devido à inserção em um programa de incentivos fiscais, sem a adoção de nenhum modelo de localização para avaliação desta estratégia. A solução gerada pelo modelo obteve menores custos totais para o novo desenho de rede em comparação com a rede atual. / [en] Including tax management in supply chain planning is a profitable differentiating factor, especially in Brazil, where each State exhibits its own tax policy. Some studies have been conducted taking into account the tax issues in the logistics network design, however this thesis takes into account the tax incentives offered by some Brazilian states to attract business. To assess the impact of tax incentives in the distribution network design, it proposed a model for locating distribution centers based on Mixed Integer Linear Programming (MILP) that includes parameters and factors related to the restrictions and opportunities created by Brazilian tax policies. The model is applied to a Brazilian company that sells chemical products. This company is installed in a location away from the end point of delivery of the products due to insertion into a tax incentive program, without adopting any location model for evaluating the strategy. The goal is to determine the actual advantages of a reduction in tax rates offset an increase in logistics transportation costs. The solution determined whether the construction of a new distribution center is beneficial, if the results generated by the model had lower total costs for the new network design compared to the current network.
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Electricity Distribution Network Planning Considering Distributed GenerationHuang, Yalin January 2014 (has links)
One of EU’s actions against climate change is to meet 20% of our energy needs from renewable resources. Given that the renewable resources are becoming more economical to extract electricity from, this will result in that more and more distributed generation (DG) will be connected to power distribution. The increasing share of DG in the electricity networks implies both increased costs and benefits for distribution system operators (DSOs), customers and DG producers. How the costs and benefits will be allocated among the actors will depend on the established regulation. Distribution networks are traditionally not designed to accommodate generation. Hence, increasing DG penetration is causing profound changes for DSOs in planning, operation and maintenance of distribution networks. Due to the unbundling between DSOs and electricity production, DSOs can not determine either the location or the size of DG. This new power distribution environment brings new challenges for the DSOs and the electric power system regulator. The DSOs are obliged to enable connection of DG meanwhile fulfilling requirements on power quality and adequate reliability. Moreover, regulatory implications can make potential DG less attractive. Therefore regulation should be able to send out incentives for the DSOs to efficiently plan the network to accommodate the increasing levels of DG. To analyze the effects of regulatory polices on network investments, risk analysis methods for integrating the DG considering uncertainties are therefore needed. In this work, regulation impact on network planning methods and network tariff designs in unbundled electricity network is firstly analyzed in order to formulate a realistic long-term network planning model considering DG. Photovoltaic (PV) power and wind power plants are used to demonstrate DG. Secondly, this work develops a deterministic model for low-voltage (LV) networks mainly considering PV connections which is based on the worst-case scenario. Dimension the network using worst-case scenario is the convention in the long-term electricity distribution network planning for the reliability and security reason. This model is then further developed into a probabilistic model in order to consider the uncertainties from DG production and load. Therefore more realistic operation conditions are considered and probabilistic constrains on voltage variation can be applied. Thirdly, this work develops a distribution medium-voltage (MV) network planning model considering wind power plant connections. The model obtains the optimal network expansion and reinforcement plan of the target network considering the uncertainties from DG production and load. The model is flexible to modify the constraints. The technical constraints are respected in any scenario and violated in few scenarios are implemented into the model separately. In LV networks only PV connections are demonstrated and in MV networks only wind power connections are demonstrated. The planning model for LV networks is proposed as a practical guideline for PV connections. It has been shown that it is simple to be implemented and flexible to adjust the planning constraints. The proposed planning model for MV networks takes reinforcement on existing lines, new connection lines to DG, alternatives for conductor sizes and substation upgrade into account, and considers non-linear power flow constraints as an iterative linear optimization process. The planning model applies conservative limits and probabilistic limits for increasing utilization of the network, and the different results are compared in case studies. The model’s efficiency, flexibility and accuracy in long-term distribution network planning problems are shown in the case studies. / <p>QC 20140217</p> / Elforsk Risknanlys II
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Privacy Concerned D2D-Assisted Delay-Tolerant Content Distribution SystemMa, Guoqing 28 April 2019 (has links)
It is foreseeable that device-to-device (D2D) communication will become a standard feature in the future, for the reason that it offloads the data traffic from network infrastructures to user devices. Recent researches prove that delivering delay-tolerant contents through content delivery network (CDN) by D2D helps network operators increase spectral and energy efficiency. However, protecting the private information of mobile users in D2D assistant CDN is the primary concern, which directly affects the willingness of mobile users to share their resources with others. In this thesis, we proposed a privacy concerned top layer system for selecting the sub-optimal set of mobile nodes as initial mobile content provider (MCP) for content delivery in any general D2D communications, which implies that our proposed system does not rely on private user information such as location, affinity, and personal preferences. We model the initial content carrier set problem as an incentive maximization problem to optimize the rewards for network operators and content providers. Then, we utilized the Markov random field (MRF) theory to build a probabilistic graphical model to make an inference on the observation of delivered contents. Furthermore, we proposed a greedy algorithm to solve the non-linear binary integer programming (NLBIP) problem for selecting the optimal initial content carrier set. The evaluations of the proposed system are based on both a simulated dataset and a real-world collected dataset corresponding to the off-line and on-line scenarios.
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