|
|
Measuring and recordes electrical electrical quantities
Vít, Tomáš ; Čejka, Miloslav (referee) ; Havlíková, Marie (advisor)
The aim of this Bachelor's thesis is the design and realisation of a device able to measure and record electrical quantities - voltage, current and resistance. The part of design is a theoretical description of measurement methods with the selection of suitable components. Based on these components is designed hardware design of the device, followed by its practical assembly. The final device is able to be measured electric variables at centain intervals, which are then stored on the SD card. The final element is the CSV file containing the measured data and time of each measurement.
|
|
|
Power Inverter Online Diagnostics
Knobloch, Jan ; Chlebiš,, Petr (referee) ; Drábek,, Pavel (referee) ; Klíma, Bohumil (advisor)
This doctoral thesis focuses on the problems of IGBT failure prediction in pulse converters using measurable changes of selected parameters (so--called trending variables) being influenced of transistor degradation during aging. Firstly the state--of--the--art in this field is presented in the dizertation. The description of designed and constructed automated measurement stand follows, enabling monitoring and recording of switching processes during accelerated aging. Further the problems of high--bandwidth measurement of electrical quantities during IGBT switching are described. Especially the problems of current sensing are analyzed and the most suitable sensor is selected. The data recorded using the developed apparatus served to identify potential trending variables allowing the failure prediction. Here the dependence of trending variables on aging and on parasitic influences (current, temperature, voltage) had to be distinguished. Finally the evaluation of trending variables is performed. Their insignificant sensitivity on accelerated aging is shown which complicates their practical implementation for the purpose of failure prediction.
|
|
|
Smart plug with consumption measurement
Hudák, Filip ; Mišurec, Jiří (referee) ; Lattenberg, Ivo (advisor)
The master thesis is devoted to the design with the following implementation and realisation of the smart socket. The theoretical part discusses already existing solutions on~the market and familiarizes with the methods of measuring the power of electricity, which are used later in the thesis. The next part of the design of the smart socket, the thesis deals with it's own design of the smart socket and the analysis of individual components, from the microprocessor, analog-to-digital converter to the individual components that measure voltage and current. The last part of the thesis involves in the realization of~a~schematic design, the production of printed circuit boards where the circuit boards are divided into two parts, the part with alternating current and the part with direct current. Last but not least, there is a program part that includes the main program for the ESP32 microcontroller and an Android application which displays measured and calculated values, with the possibility of controlling the smart socket wirelessly. The final solution to the given problem is a device that measures voltage and current and displays the results to the user via a web application and an Android application. It will mainly be used in places where it is not possible to offer socket management via the cloud.
|
|
|
Peristaltic Pump Controll Unit
Charvát, Jakub ; Kopečný, Lukáš (referee) ; Ligocki, Adam (advisor)
The work deals with the problematic of peristaltic pumps and it collects theoretical background information of this topic. The primary goal of the work is the implementation of peristaltic pump and the implementation of protection against equipment damage by overpressure. The overpressure evaluation system in this thesiss on the principle of current measurement of the motor pump. In this work, this premise is successfully tested and applied to the device. Another goal of this work is to create a desktop application that will monitor and control the pump. he data between the application and the device were successfully transfered by the MQTT communication protocol. The communication between the computer and the pump has been tested successfully.
|
|
|
Coaxial Multiplexer For Automatic Measurementof Ac Current
Boštík, Ondřej
The paper presents recent work on measurement automatization at the Czech Metrology Institute (CMI) in Brno. The purpose of designed equipment is to automatically switch current shunts during the calibration procedure of precise current sources. The article presents some of the main components including voltage follower and coaxial multiplexer itself and the final solution.
|
|
|
Passive Balancer For Eight Cell Battery Lifepo4 Pack
Herceg, Erik
This Article deals with the passive balancer that is required in all multi-cell battery systems. The balancer is designed for eight LiFePo4 battery cells that are connected in series, to achieve the required voltage of about 28 V. Each cell has a capacity of about 9600 mAh, resulting in a 80 Ah battery back. The balance algorithm is performed by main STM32 microcontroller (MCU), which controls eight balancing transistors. For measuring battery cell voltages, there are two variants of cell measurement. The first alternative of cell measurement is a battery monitor IC, which is also capable of low side current measurement and as protection it also drives the low side current transistor switch, which protects powered device. Other options are measurement by 14-bit analog to digital converter (ADC) or with internal ADC of MCU. The balancer circuit also includes an RS485 interface for communication with other devices.
|
|
|
High resolution ammeter
Honek, Marek ; Roubal, Zdeněk (referee) ; Steinbauer, Miloslav (advisor)
A transmission electron microscope is a device operating on a similar principle as an optical microscope. The fact that electrons wavelength is much shorter than the wavelength of photons is used to obtain huge magnifications. Glass lenses commonly used in the optical microscope are therefore replaced by magnetic coils in the electron microscopes. A magnetic field is directly proportional to the current passing through these coils. It is important to the current supplied to the coils to be as stable as possible to achieve high resolution. The goal of this thesis is to analyze usable current measurement methods and to design a current stable measuring device with a resolution of 1 ppm.
|
|
|
Power controller for Formula Student monopost
Sanetrik, Štefan ; Šteffan, Pavel (referee) ; Bohrn, Marek (advisor)
This bachelor´s thesis deals with design of power management unit for single seater Formula Student car. In first part are defined requirements for power management unit. In next part CAN protocol which, will be used for communication with system of the car, is introduced. Third part of thesis deals with circuit design. Mechanical design of device is introduced in next part followed by introduction of software Last part of thesis is focused on comparison of wanted and achieved parameters and conclusion of achieved results.
|
|
|
Power Inverter Online Diagnostics
Knobloch, Jan ; Chlebiš,, Petr (referee) ; Drábek,, Pavel (referee) ; Klíma, Bohumil (advisor)
This doctoral thesis focuses on the problems of IGBT failure prediction in pulse converters using measurable changes of selected parameters (so--called trending variables) being influenced of transistor degradation during aging. Firstly the state--of--the--art in this field is presented in the dizertation. The description of designed and constructed automated measurement stand follows, enabling monitoring and recording of switching processes during accelerated aging. Further the problems of high--bandwidth measurement of electrical quantities during IGBT switching are described. Especially the problems of current sensing are analyzed and the most suitable sensor is selected. The data recorded using the developed apparatus served to identify potential trending variables allowing the failure prediction. Here the dependence of trending variables on aging and on parasitic influences (current, temperature, voltage) had to be distinguished. Finally the evaluation of trending variables is performed. Their insignificant sensitivity on accelerated aging is shown which complicates their practical implementation for the purpose of failure prediction.
|
|
|
Draft sources 1000A AC current sensors for calibration
Klimeš, Jan ; Vetiška, Vojtěch (referee) ; Dohnal, Petr (advisor)
This bachelor thesis deals with design and construction of device for precise measurement of 1000 A alternate current. This thesis theoretically discusses the possibilities of conventional solutions, such as current transformers, as well as modern methods in the form of current sensors. The output of this thesis is a solution of problems with accuracy and discussion of other possible ways to reduce systematic error. The thesis discusses structure of the current transformer, the digitalizing of the signal and its usage as an input for engineering units. The device is then tested for final accuracy.
|
guest ::
