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Evaluation of Possibility of New Source Connection With Regard to Nodal Voltage
Němec, Jan ; Topolánek, David (referee) ; Toman, Petr (advisor)
Connection new source of electrical energy into distribution network is important for existing one for reasons its rating and dimensioning. It is even evaluate, whether possibility connection new source in to network is real and do not endanger continuous running distribution system. This work has shown, what conditions are need realize for connection source into distribution network in view of voltage ratio. Next it must incidence harmonic current and affecting centralized telecontrol signal about reasoning. Against a background examination connection source are administrative acts, which forms basis of successful connection. On basis lets request of connection mostly study of connection working up. This study contains concrete calculation and examination individual factors for connection new source. Next put mind to connection wind power station, because wind power stations are very special source for connection into distribution network. Bigger demands are putting on them and stricter examination of connection to site must be done. Because during time unit (day, week and month) they have various strain diagram. Which makes higher straining of distribution and necessity have reserve of electrical energy for case fail wind power station owing to windless ness. In the end, there is referred to practical examination example of possibility connecting. As this example was chosen examination of wind park to 110 kW network with 32 MVA installed power from view of voltage ratio. Solution process is given by replacement of part of given Picells link and by calculation steady state of node site system with Gauss-Seidels iteration method. After that follows evaluation of voltage change in the site before and after connection of source to the network, which can not be higher than 2%. In this example is this condition satisfied and from a view of voltage ratio there is nothing to obstruct for connection new source to network.
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The calculation of the short circuits of the given network
Bordovský, Lukáš ; Paar, Martin (referee) ; Toman, Petr (advisor)
The main aim of this Bachelor thesis is to introduce you a calculation of short-circuit rates in compliance with IEC 60909, and a subsequent calculation of a scheduled real network. The thesis itself is divided into two parts : a theory about the short-circuit problems and a simple model example are stated in the first part, in the second part is stated the calculation of the given real network for the case of an occurence of shunt faults at distribution points, namely a three-phase fault, a two-phase isolated fault, a double-phase-to-earth fault and a single phase fault. The work is coupled with a determination of current and voltage rates at points P and K. At the point P is situated distance protection relay and at the point K comes the shunt fault. The calculations are done with a method of successive simplification.
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R290 heat pump
Toman, Petr ; Pospíšil, Jiří (referee) ; Hejčík, Jiří (advisor)
This diploma thesis deals with design of air-water heat pump which uses natural refrigerant, propane. In the thesis there are mentioned various types of devices using the source of low-potential heat for heating. The main part of the thesis is the design of the heat pump cooling circuit. In this section, individual components are designed, the calculation and comparison of the heating factor for different operating parameters is performed. Finally, the construction of the coolant circuit and the air exchanger is designed.
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Ground Fault Location in Compensated Distribution Network
Topolánek, David ; Janíček,, František (referee) ; Mišák,, Stanislav (referee) ; Toman, Petr (advisor)
The most widespread system of an earthing neutral point of a supply transformer in a MV network is an earthing through an arc-suppression coil. In this case of a resonant-earthed power system a fault current is compensated by the suppression coil and only residual current flows through a fault point. A value of the residual current is much smaller then a value of an original capacitive current of the network and is not dependent on the fault location. According to that reasons it is really complicated to fast and accurately determine the fault point location. Since nowadays used methods for the ground fault location inside wide distribution networks have a lot of disadvantages, the thesis is focused on a proposal of a new method for the ground fault location especially inside of a compensated network. The main reasons for a consecutive installation of power quality meters into distribution transformer substations are a power quality monitoring and a global evolution of an electrical network onto the “SmartGrids”. In case that all results from the meters are properly synchronized and centralized, new possibilities of control or of an evaluation of a network are enabled. This doctoral thesis proposes the possibility for the ground fault detection with an aid of synchronized records recorded on the low-voltage side of the distribution transformers 22/0.4 kV into the network equipped with automatics for short-time increasing of an active part of a faulty current. The described method uses a voltage drop evoked by connecting of the auxiliary resistor for location of the faulty section. The proposed method is tested with help of numerical model which presents a part of the distribution network Series of simulation are executed and correct function and force function of the method is reviewed. Finally the thesis describes real experiment and also a confrontation between simulation and real measuring, and also possibilities of method usage are commented.
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Application of Sensors and Digitalization Based on IEC 61850 in Medium Voltage Networks and Switchgears
Štefanka, Martin ; Braciník, Peter (referee) ; Müller,, Zdeněk (referee) ; Toman, Petr (advisor)
Vzduchem izolované vysokonapěťové rozváděče jsou nedílnou součástí energetického distribučního řetězce a to jak v průmyslovém, tak ve veřejném sektoru. Hlavní funkcí rozváděče je ochrana pracovního personálu, rozpojování/odpojování a spínání, izolování, měření proudů a napětí, chránění a ovládání zatížení a komunikace dat do řídících systémů. V každé z výše zmíněných funkcí probíhal technologický vývoj v průběhu posledních 40 let. Dnešní rozváděče jsou spolehlivé a elektrickému oblouku odolné zařízení, zoptimalizované téměř k fyzikálním limitům dielektrických, elektromagnetických a termodynamických polí. Vakuové vypínače zajišťují stálou a spolehlivou vypínací funkci. Taktéž v oblasti chránění, řízení a komunikace došlo k mnoha technologickým proměnám. Od elektromechanických relé přes zařízení založená na tranzistorech, později na jednoúčelových mikroprocesorech, až po dnešní multifunkční vysoce výkonná mikroprocesorová inteligentní elektronická zařízení. Pouze oblast měření proudů a napětí setrvala z technologického hlediska posledních 40 let beze změny. K dominujícím měřícím technologiím dneška stále ještě patří indukčně založené transformátory proudu a napětí. Byly sice provedeny některé pokusy k obměně technologie měření jako takové, nicméně bez dosažení úspěchu. Tato dizertační práce je zaměřena na poskytnutí nového náhledu na alternativní technologii měření v elektrických sítích a ve vzduchem izolovaných vysokonapěťových rozváděčích, kterou lze využít jak pro měření proudu, tak i napětí. Tato práce vysvětluje, proč Rogowského cívky, odporové a kapacitní děliče jsou tou správnou volbou a měly by být použity ve vysokonapěťových rozváděčích a podrobně analyzuje přesnost měření a jejich příslušné meze. Dále tato práce popisuje, že pro nasazování nových měřících technologií musí být postupováno systematicky. Senzory připojené k inteligentním elektronickým přístrojům a schopností komunikace založené na IEC 61850 spolu s vysokorychlostní komunikační sběrnicí Ethernetu vytvoří systém, který zjednoduší a sjednotí konstrukci rozváděčů a umožní oddělit aspekty projektování měření od studie zkratových selektivit. V práci je také uveden příklad, jak tento nový systém může přinést změny a zjednodušení do oblastí projektování a řízení. V této práci jsou popsány výsledky několikaletého úsilí při stanovení nových měřících a digitalizovaných přístupů ve vysokonapěťových rozváděčích pod autorovým vedením. Toto úsilí také vedlo k uvedení nového produktu – UniGear Digital - konceptu od ABB. Závěrečná část práce demonstruje praktické nasazení všech výsledků v této práci při skutečných aplikacích.
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Business Plan – Tennis Center
Toman, Petr ; Odehnal, Tomáš (referee) ; Heralecký, Tomáš (advisor)
The diploma thesis deals whit possibility of establishing a tennis center in chosen locality. In the first part this diploma thesis deals whit gathering theoretic ways, in the second part than with establishing a Tennis centre itself. This part includes analysis of competition and market, potential customers and business plan. The outcome of my thesis is comprehensive project on establishing the Tennis centre.
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The calculation of the distance protection relay setings for HV line
Doležal, Marek ; Vaculík, Petr (referee) ; Toman, Petr (advisor)
I divided this work into two parts: theoretical and practical. The first part deals with theoretical calculation of setting for distance protection of high voltage line, possible defective states, which can appear on this network, and methods of calculating these defective states. The second part deals with application of the earlier described theory to calculation of distance protection for specified part of the network. The results of this work are all the parameters needed for setting of distance protection for one part of the network.
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Using Biomass for Cogeneration of Heat and Electricity
Vašíček, Martin ; Macháček, Jan (referee) ; Toman, Petr (advisor)
Theoretical part is concerned to disposal of biomass kinds and various forms of applications. The basic characteristic for each kind of biomass and their forms are presented. Characteristics of energy plants and woods are more detailed. In work are described two fundamental kinds of combustion, fluid combustion and grate combustion, which are used in power plants and heating plants. The work describes process of gasification and obtaining wood gas from biomass. Evaluation of (energy plants, wood biomass and the rest from agriculture production – straw) in light of heating power, treatment, handling, ash creation and environment pollution is provided. Work is concerned to redemption price history, volume of produced biomass and perspective to future. Czech Republic legislation gives support to biomass usage by guarantee for electric energy purchasing and same redemption price perspective. Explain term of cogeneration, possibility of cegeneration units application – their kinds with fuel usage aspect (biogas, natural gas, wood gas). Practical part is concerned to design of such kind of unit. Cogeneration unit will be installed in company, which producing wood. For this reason will be used wood biomass to produce wood gas. Size of unit, fuel consumption, and cost saving in comparison to electric energy together with recovery of investment are calculated. In work is drawn out possibility to connect this unit to distribution electrical network, possibility of electric energy distribution and due this to improve backflow. Noticeable are possibilities to get state grant from various grant sources.
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