|
|
Non-standard methods of current and voltage measurements
Talába, Michal ; Boušek, Jaroslav (referee) ; Hubálek, Jaromír (advisor)
This work brings a study about non-conventional methods of voltage and current measurement, followed by a creation of magneto-resistive material based current sensor prototype, suitable for medium voltage switchgear from ABB. Outcome of the study is description of physical principle and the measurement principle of non-conventional methods. Outcome of the experimental part is a current sensor based on magneto-resistive component, which can measure magnetic field generated around a wire with flowing primary current. Through the magnetic field, the sensor can measure primary current flowing in the wire. Sensor was measured in range 0 – 1000 A, and its accuracy and linearity was approximately 6%. The main contribution of this work is the confirmation that this non-conventional method works for measurement of high currents. Based on the outcome, ABB can decide whether is this technology suitable for its product portfolio.
|
|
|
Current sensor signal processing using microcontroller
Tlustoš, Luboš ; Chytil, Jiří (referee) ; Friedl, Martin (advisor)
In this thesis is described Wiegand wire, current sensor using Wiegand wire effect and processing the output signal from the current sensor using a microcontroller. The document is divided into chapters, each of which are generally described microcontrollers and their applications to signal processing. It also describes the design of circuits for generating sine wave, circuits for appropriate adjustment of the output signals from the sensor current and a draft power source.
|
|
|
Analysis of the electrical power measurement system in the local distribution network Pod Palackého vrchem
Hájková, Barbora ; Orságová, Jaroslava (referee) ; Jurák, Viktor (advisor)
The diploma thesis introduces a detailed analysis of the local distribution system (LDS) Pod Palackého vrchem (PPV) in the Brno, parameters of power transformers and cable routes between them. The elements of the electrical network that are influencing the balance of reactive power are described along with its sources and appliances. In the next part is defined the present concept of long-term measurement in the LDS by using current and voltage sensors. This part deals with calculations of power losses in the power transformers and the cable lines together with uncertainties concerning power measurement in the field of energetics. The essential part of the thesis focuses on the analysis of the temporary measurement implementation in the LDS, data processing along with the comparison of measured values from temporary measurement with values from permanent measurement. In conclusion, the error of the system is determined.
|
|
|
Universal control unit for life test of motors
Ševčík, Šimon ; Macháň, Ladislav (referee) ; Musil, Vladislav (advisor)
This thesis describes theway of BPM motors control and its use in life testing. Firstly it describes the properties of motors and their differences. Secondly it describes possibilities of motor control and their need for life testing. Finally it describes proposal of the universal control unit, types of controling, programming part and technical documentations.
|
|
|
Current sensor with digitized output signal
Hanuš, Ivan ; Vágner, Martin (referee) ; Havránek, Zdeněk (advisor)
The objective of this thesis is to describe principles of measuring of alternating current in low voltage power supply network with Rogowski coil and to study details of requirements for electronic current sensor with digital output. Furthermore to study the current solution of digitalization of output signal from Rogowski coil and to determine metrological characteristics of the digitalization module for processing the signal from the Rogowski coil as current sensor and to design a concept of an electronic current sensor unit with Rogowski coil and the digitalization module with the expected optical output. The theoretical part deals with the measurement of current using Rogowski coil, its characteristics and advantages compared to conventional current transformers. Further in the thesis there are specified the requirements for current sensor. The practical part deals with the design of digitalization module consisting of a pair of AD converters, a microcontroller and output circuits. Furthermore, the thesis deals with digital signal processing of signal from Rogowski coil. Furthermore, the thesis describes firmware for microcontroller and PC application. The result of thesis is functional circuit of electronic current sensor that processes signal from Rogowski coil and converts it to digital form.
|
|
|
Switching supply source 5,5kV/4,3kW with silicon-carbide semiconductors
Gabriel, Petr ; Patočka, Miroslav (referee) ; Vorel, Pavel (advisor)
This thesis is about to introduce the development of switched power supply with output voltage of 5,5 kV and power of 4,3 kW. This thesis directly follows the outputs of two previous semester projects. Main task is about to finish the development of remaining printed circuit boards and perform launching of all parts of developed power supply. Next necessary task is about to assemble a functional prototype of the supply using the developed parts, performing a series of measurement supply’s parameters and creating of technical documentation of mechanical part. There are all stages of supply’s development included in this thesis. From the first part, that describes various types of converters, through the design of all the supply’s parts, to final implementation of functional prototype. There are the results of measurement supply’s parameters at the end of this thesis.
|
|
|
Comparison of conventional CT and VT with current and voltage sensors
Dvořák, Petr ; Drápela, Jiří (referee) ; Orságová, Jaroslava (advisor)
The diploma thesis deals with conventional transformers and current and voltage sensors. The first half of thesis describes mainly the basic concepts and accuracy classes of these converters used in electrical substations. The emphasis is given primarily on the differences. In the second half of thesis is presented an exact type of converters, which are installed in the substation Medlánky. There is an analysis of measured data from long – term monitoring from this substation and comparing the results from conventional transformers compared to the results from more modern sensors.
|
|
|
Comparison of Instrument Transformer and Sensor Applications in Feeder Terminal REF 542plus
Hrycík, Tomáš ; Majer, Karol (referee) ; Orságová, Jaroslava (advisor)
The aim of this Master´s thesis is use of instrument transformers and sensors on field of industry protection. We will compare current and voltage transformers, current sensor – based on Rogowski coil, voltage sensor – based on voltage divider. By this measure devices, we can monitoring values of analog quantities in medium voltage switchgear. It is impossible to compare, measure and analyze without this measure devices. There is protection terminal REF542plus, which can compile this values. The REF542plus ability are measuring, monitoring, remote control and protection. First, we will discuss about theory of sensors and convential instrument transformers and analysis of analog signal. We will compare analog input channel on sensor´s analog module and transformer´s analog module. There are few differences between type of analog modules. For analog signal analysis are important frequency filters and Analog/ Digital Convertor (sigma-delta). We will describe functions and options of REF542plus. In practical part of this project, we will test protection functions of protection terminal. First, protection terminal will be connected to sensors. Second protection terminal will be connected to transformers. For testing we chose Earth-fault directional protection and differential protection. We will make only secondary tests. That´s mean, input analog quantities to REF542plus will be simulated by tester. In all we will verify quality of protection. We will focus on lower settings of protection and we will inject protection by low current. Objectives are testing of trip characteristics and measuring of trip time.
|
|
|
Design digital optical output
Kubáč, Stanislav ; Beneš, Petr (referee) ; Klusáček, Stanislav (advisor)
This work descibes general principles of measuring the alternating current and voltage using conventional and unconventional sensors.This work shows specific parmeters conected with principles of the measurement, advantages and disadvantages of individual measuring procedures, types of output signals, precisions, limitations, ways of power and so on. Part of the work is to find optimal measurement procedure, which can be aplicated to practical measuring of alternating currents and voltage. Main part of the work concerns the realisation of optimal method of measuring alternating current.
|
|
|
Measuring of Electricity Consumption Utilizing Current Transformer and Arduino Platform
Pokorný, Rostislav ; Pokorný, Jiří (referee) ; Štůsek, Martin (advisor)
The aim of this bachelor thesis is implementation of non-invasive platform for measuring the consumption and production of electrical power. Developed device enables visualization of measured data on display. Electric current is measured by non-invasive current sensor equipped with split core made of ferrite. Measured data are processed on single board microcomputer called Arduino. The device enables wireless communication with a server platform that allows visualization of measured data in a simple graphical user interface based on the ThingSpeak platform. Created device can measure consumption or production of electrical power on appliance with maximum current up to 30 A without need of any changes in electric circuit.
|
guest ::
