Ing. Ján Tomlain, Ph.D.

This paper deals with using low-cost radio modules for indoor localization purposes. A comparison of the various positioning techniques is introduced in the beginning parts. In addition, the trilateration method's mathematical background is briefly introduced. Bluetooth Low Energy has been chosen for real environment tests and deployment of the proposed methods. The system consists of newly developed and manufactured hardware units. The paper then describes the microprocessor and post-processing algorithms used. The designed system was installed in the laboratory room for verification and measurement purposes. Finally, the platform was evaluated regarding the final accuracy in the real installation.

In the field of energetics there is an amount of high-voltage (HV) machines those lifetime is expected of the order of tens of years. As an example the power transformers and generators directly used in the production and the transmission of electricity may be mentioned. To achieve the expected lifetime, it is necessary to plan regular diagnostic examinations of these machines, thus the machine operator avoids an unexpected shut down of the machine or the entire system. There are a few measurements methods used to assess the state of the machine. This abstract further deals only with frequency response analysis (FRA) and frequency domain spectroscopy (FDS) which is a special case of dielectric spectroscopy. A brief description of the methods is stated. Similarities between these requirements are analysed in terms of common functional blocks of the instrumentation.

This paper discusses the problems of the noninvasive diagnostic of high-voltage machines. The main role of the diagnostic is to predict an upcoming machine failure. Frequency response and frequency domain spectroscopy methods are studied in this paper. The methods are compared in terms of common instrumentation features. A development of a hardware platform intended for both methods is presented. The platform is evaluated in the terms of accuracy and compared with laboratory instrumentation. The results of the evaluation showed the proposed solution is able to implement both methods and have a measurement accuracy comparable with market available instruments implementing only one method

The new trends of electrical grids lead to an intelligent power grid able to adapt to the current power consumption in real time. A modern electrical grid also should be able to manage quite a number of smaller renewable power sources and the different specific electrical devices connected to the grid. Such system considers two-way electricity flow depending on current needs. To achieve such functionality of the power grid, it is necessary to provide data exchange and proper communication technology between particular grid nodes has to be chosen as well. A definition of Smart Grid system is described, and a few conceptual models are mentioned. This paper further deals with Power Line and Internet of Things communication. The technologies such as Sigfox, LoRa and NB-IoT are surveyed with an intention to integrate the Smart Grid into an Internet of things network. The main advantages and disadvantages for use in Smart Grid systems are stated. The paper further deals with a desing of a custom hardware platform suitatable for an implementation Power Line Communications and Internet of Things networks in Smart Grid systems. The platform is design as a customizable system, that allows the user to choose the proper communication standard depending on a particular installation requirement. Last but not least, communication range, reliability and consumption tests are evaluated.

This paper deals with a comparison between digital and analog implementation of a synchronous detection algorithm. The commonly used implementation methods of synchronous detection are stated within the paper. The paper describes FPGA-based digital and analog hardware approaches, focusing on the digital design. The characterizations of the used analog-to-digital converters are measured. A direct comparison between both proposed approaches in terms of sensitivity along with long-term stability is described. The results achieved, along with identified limitations and proposed improvements are widely discussed.

This paper describes a development of a hardware platform suitable for the frequency domain spectroscopy (FDS) and frequency response analysis (FRA) applied for high-voltage machines diagnostics. The principle of the FDS and FRA methods widely used by maintenance technicians are briefly reminded. Important technical requirements for the instruments utilizing these methods are stated. A design of a hardware platform with parameters fitting both of the method and engagement of the latest electronics components is discussed. In order to verification of the design platform, a basic implementation of a vector voltmeter is described. Long term stability, phase shift sensitivity, and accuracy of the platform are evaluated.

The paper deals with the problematic of the interoperability island smart renewable sources with smart concentrator unit. These sources are built up on smart regulators and communication module. It is focused mainly on the island localities without direct electrical connection, which should be interconnected with central concentrator unit. The theory contains little bit about regulator algorithm, block diagram of both power regulation and communication part and a few about fundamentals. There is shown how should be smart concentrator unit developed and what is the important for online monitoring of these island systems. Evaluation and measured electrical, communication parameters and results follows the papers.

The new trends of electrical grids lead to an intelligent power grid able to adapt to the current power consumption in a real time. A modern electrical grid also should be able to manage quite a number of smaller renewable power sources connected to the grid. Such system considers two-way electricity flow depending on current needs. To achieve such functionality of the power grid a proper communication technology between particular grid nodes has to be chosen. This paper deals with problematics of communication possibilities in a Smart Grid systems. A definition of such system is described, and a few conceptual models are mentioned. This paper further deals with Power Line and Radio Frequency communication. Also technologies such as Sigfox, LoRa and NB-IoT are surveyed with an intention to integrate the Smart Grid into an IoT network. The main advantages and disadvantages for use in Smart Grid systems are stated. The next chapter deals with a market research of available electronic parts or modules suitable for an implementation PLC and RF networks in Smart Grid systems. Last but not least a hardware implementation of both methods are mentioned, and some range and reliability test are evaluated.

This paper describes a developing of an analog to digital front-end suitable for the frequency domain spectroscopy (FDS) of high-voltage machines. The principle of the FDS is described and the requirements for the instruments utilizing this method are stated. The design of the front-end is described as a base of an FDS analyzer instrument. A basic implementation of the vector voltmeter is described. The implementation is verified in order to a long term stability and a phase shift sensitivity.

This paper deals with a design of a hardware platform for frequency response analysis (FRA) testing for non-invasive diagnostic purposes. Commonly used diagnostic methods are described as well as the theory behind the FRA measurement itself. The paper describes designed FPGA-based digital platform. Characterization of the digital board is followed by first high speed analog to digital conversion testing. Achieved results with identified limitations and proposed improvements are finally discussed.

The paper deals with the problematics of the smart renewable sources which are implemented with smart regulators and communication module. It is focused mainly on the island localities without direct electrical connection. The theory contains little bit about regulator algorithm, block diagram of both – power regulation and communication part and a few about fundamentals. The suitable components and semiconductors are chosen and described. Evaluation and measured electrical parameters follows the papers.

This paper describes a developing of an analog to digital front-end suitable for the frequency domain spectroscopy (FDS) of high-voltage machines. The principle of the FDS is described and the requirements for the instruments utilizing this method are stated. The design of the front-end is described as a base of an FDS analyzer instrument. A basic implementation of the vector voltmeter is described. The implementation is verified in order to stability, a phase shift sensitivity and accuracy.

The paper deals with the problematics of the distributed control units in the outdoor training polygons which are implemented with a wireless communication unit. The work is mainly focused on the multi-hop mesh capabilities of wireless communication modes. The theoretical part contains information about wire/wireless networks, a block diagram of the training-control unit and basic fundamentals. The suitable components and semiconductors are chosen and possibilities of ZigBee, WiFi, ISM (Industrial, Scientific and Medical) radio bands are described. A system evaluation, measured range distance and communication parameters follow the paper.

This paper deals with the complex design of the partial discharge system for high-voltage machines diagnostics. The result of the work is complete measurement system, which fulfils specified functionality. Implementation relies on the FPGA with the advantage of system-on-the-chip technology. This solution enables flexible and powerful signal processing. Measurement principles and methods together with the test results are also mentioned.

This paper describes a hardware design of a fully digital wideband PD meter based on application of FPGA as well as design of coupling device required for PD measurements. The designed coupling device has frequency bandwidth of 1 kHz - 10 MHz. The PD signal is digitalized by a fast 14-bit A/D convertor sampling at frequency of 50 MSa/s. The digital samples of PD signal are read by the FPGA, subsequently filtered by a number of digital FIR filter banks and stored in a 32 MB SDRAM memory. On request from PC software, the FPGA send samples in reduced form through Ethernet interface for the next signal processing and evaluation all important parameters of PD analysis. The paper also describes a design of smart charge calibrator especially developed for the PD meter testing and calibration.