The introduction of own power sources at production facilities under the conditions of joint operation of autonomous and centralized power sources of power supply systems of production facilities requires the assessment of the existence of the main production modes. For this purpose a mathematical model of the power supply system with autonomous and centralized sources has been developed, which takes into account the closed electrical network of sewage treatment plants of a large city. Calculated studies of start-up schemes of a powerful blower drive in the autonomous and centralized system are performed. To increase the accuracy of calculations of residual voltages and motor starting parameters, the proposed mathematical model takes into account the control of EMF angles of generators, synchronous (SM) and asynchronous motors (AM) relative to the EMF of the balancing unit. The network parameters are taken into account by complex resistances, and the parameters of blower drives and other mechanisms are recalculated when the angular speed of rotation changes. Calculated studies have confirmed that in the scheme of autonomous power supply with four generators the direct start of SM with capacity 1.3 MW is possible, but at the same time the start-up time increases up to tp = 11.7 sec, and the voltage on sections of switchgear and transformer substations decreases to the value U = 0,67 o.u. It is recommended to use a soft-start scheme for SM of turbo blower with capacity of 1.3 MW, which will allow to avoid significant voltage drop during the start-up period even in the scheme of autonomous power supply from generators of mini-station, as well as to increase the number (capacity) of generators of mini-station.

In order to meet the requirements of Rostechnadzor for unloading the supplying substation CPS-11 different technical solutions were considered, which were then implemented in practice. For this purpose, a mathematical model of the power supply scheme of the CPS-11 substation was developed. Calculations of normal modes of operation of electrical equipment CPS-11 have been made in order to determine steady-state parameters of the substation CPS-11 at changing: power of compensating devices, the power factor of synchronous motors, the use of backup synchronous motors as reactive power compensators, modes of operation of sections of the switchgears. The mathematical model takes into account the operating synchronous motors, type and mode of operation of the excitation system. Calculation studies were performed for the following cases: separate operation of 35 kV transformers, parallel operation of 35 kV transformers and during preventive maintenance on one transformer. The calculation of economic effect from the introduction of additionally installed capacitor banks was performed in this work.

Data to support the paper - High-throughput crystallography for rapid early-stage fragment growth from crude arrays by low-cost robotics. Data includes a summary of X-ray and LCMS results for the reactions executed on the OpenTrons, output reports and summaries from MSCheck (semi-automated LCMS analyzer tool) and the Python scripts used to execute single and multistep chemistry on the OpenTrons. Abstract We demonstrate that a simple workflow of array synthesis, combining low-cost robotics with analytic techniques to deconvolute crude reaction mixtures, is an effective way to collect structural data on a binding site. Starting from the high information content of the crystallographic fragment screens on PHIP(2) (second bromodomain of the pleckstrin homology domain interacting protein), a collection of more than 1800 compounds was enumerated. Several thousand Crude Reaction Mixtures (CRMs) were synthesized on one robotic platform, an OpenTrons OT-1 liquid handler, using reaction sequences of up to 5 chemical steps. Analysis via MScheck, an algorithm-based system for finding a m/z in a CRM, significantly shortened product identification protocol times. 957 usable X-ray diffraction datasets were acquired, which resolved as 22 reaction products binding to the protein, 19 with conserved poses relative to the original fragment and 3 with a new, unexpected binding pose. The 22 crystallographic hit compounds were subsequently tested with peptide displacement alpha-screen assay and time-resolved grating-coupled interferometry-based biosensor assays, which confirmed one molecule with an IC50 = 34 μM and KD = 50 μM, from an inactive fragment. The procedures described are entirely formulaic and engineerable and the method is eminently scalable. We anticipate that this cheap, low solvent-use approach will yield vast amounts of data, enabling rapid SAR landscape exploration around fragments, leading to faster fragment to lead times.

The paper uses the methods of mathematical modeling and instrumental control to justify the introduction of energy-saving measures and technical solutions in the power supply systems of mining enterprises. An assessment of the implementation of energy saving methods in electric drive and power supply systems at mining enterprises demon-strated the possibility of achieving a multiplier economic effect with the right approach to the implementation and subse-quent operation of energy-saving technologies. The energy saving potential was shown in the industry in ge¬neral, and in mining enterprises in particular. For example, in some areas of enterprises, such measures as reactive power compensa-tion, the introduction of automated electric drive systems, the development and pilot operation of power quality control systems with continuous recording of indicators were considered. The mathematical modeling method was implemented using the MatLab software package which has proven itself in engineering calculations around the world. Instrumental control and evaluation of power quality indicators were carried out in accordance with the requirements of GOST RF 32144–2013. As a result of the potential optimization of individual power supply systems, the estimated total economic ef-fect due to energy savings was obtained. The figure approached 28 million rubles per year, which is on average 20% of the cost of electricity consumption of the considered sites of mining enterprises.

Air-shower radio arrays operate in low signal-to-noise ratio conditions, which complicates the autonomous measurement of air-shower signals, i.e. without using an external trigger from optical or scintillator detectors. A simple threshold trigger for radio detector can be efficiently applied only in radio-quiet conditions, because for other cases this trigger detects a high fraction of noise pulses. In the present work, we study aspects of independent air-shower detection by dense antenna clusters with a complex real-time trigger system. For choosing the optimal procedures for the real-time analysis, we study the dependence between trigger efficiency, count rate, detector hardware and geometry. For this study, we develop a framework for testing various methods of signal detection and noise filtration for arrays with various specifications and the hardware implementation of these methods based on field programmable gate arrays. The framework provides flexible settings for the management of station-level and cluster-level stages of detecting the signal, optimized for the hardware implementation for real-time processing. It includes data-processing tools for the initial configuration and tests on pre-recorded data, tools for configuring the trigger architecture and tools for preliminary estimates of the trigger efficiency at given thresholds of cosmic-ray energy and air-shower pulse amplitude. We show examples of the trigger pipeline developed with this framework and discuss the results of tests on simulated data.

In electrical networks of almost all voltage classes, the main link in the work on the transmission of electrical energy is a power transformer. At the moment, about 60% of them are operated in our country with a significant excess of service life, which increases the requirements for their technical control and diagnostics of all units. Switching devices are an integral part of power transformers. They are necessary to regulate voltage on substation busbars depending on the load of consumers. Not only the reliability of power supply of industrial enterprises, cities and agriculture, but also the quality of electrical energy depends on their operation. At the same time, they are one of the vulnerable nodes of voltage converters. Although the parameters of diagnostic signs for switching devices are not as extensive as the power transformer itself, they nevertheless require special attention from the operating personnel. This is due not only to the variety of switchgear types that exist, but also to the methods used to diagnose them. For this reason in this work an attempt has been made to analyze the existing approaches and methods of diagnosing these mechanical controlled voltage regulators. We propose a new approach in terms of diagnostics of high-voltage equipment, including power transformers – introdiagnostics. It is based on methods of non-destructive (without opening tanks and draining dielectric liquids) control of parameters that characterize the state of electrical equipment. We present an original method of diagnosing the on-load tap changer, based on oscillography and subsequent analysis of operation of the on-load tap changer contact system without draining transformer oil from the diverter switch’s tank.

The work is devoted to mathematical modeling of a DC motor rotation speed control system based on the use of a PI controller. DC motors are widely used in industry for driving cyclical mechanisms where high speed response, high starting torque, linear control are required. The main methods for controlling the required characteristics of the speed of rotation of a DC motor with independent excitation are to control the parameters of the armature and excitation windings fed from different sources. The PI controller is widely used in programmable logic controllers due to the simplicity and clarity of the mathematical apparatus. The proposed mathematical model of the PI controller is based on the choice of optimal parameters that ensure that the actual speed is kept close to the set one. The optimum PI controller coefficients KP and KI have been determined to give the best result for a constant speed. The results of computer simulation in MatLab are compared with the results of simulation on a laboratory setup. The data are obtained when using the PI controller for the steady-state error and transient time look preferable to the simulation model with voltage regulation. The developed mathematical model shows the following main results: acceleration time < 0,3 s; transient process time < 0,5 s; overshoot does not exceed 0,5 %; the steady-state error does not exceed 0,1 %. As a result of the study, a mathematical model is developed and the operation of a DC motor with a PI controller is analyzed, which makes it possible to almost completely eliminate forced oscillations and a steady-state error. The advantage of the proposed method of using the PI controller is noted as a more familiar and easy-to-use control element when implemented in existing control systems without any special changes.

THE PURPOSE. To examine the features of the location and the overall structure of theSredne-Kamchatskyisolated power hub. To considerthe structure of installed electric capacity and the composition of generating equipment of power plants in the mentioned power hub. To determine the composition and characteristics of the electric grid economy. To analyze and determine the main indicators of electricity consumption and capacity dynamics of the hub. To perform an analysis of the existing balance of power and electric energy, to determine the main technical and economic parameters of the power supply. To consider options for the power supply system development including on the basis of renewable energy sources. METHODS. When solving this problem, we usedmethods of mathematical processing of statistical data and methods of normative forecasting. RESULTS. We considered the special featuresof generating capacities and network infrastructure development,the issues ensuring the long-term and medium-term demand for electric energy and capacity, the formation of stable and favorable conditions for attracting investment in the construction of electric power facilities.The study calculated the current and prospective balances of electricity and capacity in the discussed power hubbased on the analysis of the energy structure of an isolated power unit and the dynamics of electricity consumption. CONCLUSION. Any failure in an isolated system leads to dangerous crisis phenomena and significant economic losses. Thus it is important to provide reliable and efficient power supply to energy isolated territories. The presented comprehensive assessment of the state of the electric power industry in the isolated Sredne-Kamchatsky power plant allows us to predict the prospects for its development within the framework of the overall development of the electric power complex of the Kamchatka Territory.

The current status of the equipment development for the new wide-angle gamma-ray imaging air Cherenkov telescope for TAIGA hybrid installation is presented. A front-end electronic and data acquisition system board based on the Zynq family Xilinx FPGA chips specially designed for this project have been produced and are being tested. A detailed description if presented for internal structure of the four main subsystems: four 8-channel 100 MHz ADCs, board’s control system, internal clock and synchronization system and the power supply system. Additionally, the current status of a small scale prototype telescope SIT consisting of 49 SiPM is presented. The telescope includes a digital camera for observing the stars and weather condition. The SIT-HiSCORE synchronization systems and the telemetry information collection had been tested.

High energy astrophysics has been actively developed since the last decades. The photons and neutrinos produced at astrophysical sources were detected up to energies of PeV, while the measured spectrum of cosmic rays lasts from GeV to ZeV energies. The challenges of modern detectors are not only pushing towards higher energies to reach the cosmic acceleration limit, but also increasing the resolution of the reconstruction of the energy, arrival direction and the type of the cosmic particle. Due to low flux of these particles, their detection is feasible only by measurement of air-showers, atmospheric cascades of secondary particles induced by the primary one. One of the promising methods of the air-shower detection is the sparse digital radio arrays, a young, but cost-effective technique aimed at the cosmic particles with energies beyond PeV. The future detectors aimed at detection of cosmic rays, photons and neutrinos of extreme energies are based on the antenna arrays located either in ice or on mountain slopes. The latter are sensitive both to downward-directional air-showers induced by cosmic rays, and upward-going ones produced by skimming neutrinos interacting with rock. The prototyping of such an array requires appropriate location (high-altitude mountains) with corresponding infrastructure and ideally additional cosmic-ray detector for the cross-calibration of antennas. The-Tien Shan High-altitude Scientific Station (TSHSS) located near Almaty, Kazakhstan, and equipped with air-shower instruments, is an ideal place for this prototype. In this work we discuss the prospects of the radio technique, its current challenges and report the recent advances of the prototype radio installations at TSHSS.

The Tunka Radio Extension (Tunka-Rex) is a digital antenna array located in the Tunka Valley in Siberia, which measures the radio emission of cosmic-ray air-showers with energies up to EeV. Tunka-Rex is externally triggered by the Tunka-133 air-Cherenkov timing array (during nights) and by the Tunka-Grande array of particle detectors (remaining time). These three arrays comprise the cosmic-ray extension of the Tunka Advanced Instrument for cosmic rays and Gamma Astronomy (TAIGA). The configuration and analysis pipeline of Tunka-Rex have significantly changed over its runtime. Density of the antennas was tripled and the pipeline has become more developed forming now sophisticated piece of reconstruction software. During its lifecycle Tunka-Rex has demonstrated that a cost-effective and full duty-cycle radio detector can reconstruct the energy and shower maximum with a precision comparable to optical detectors. Moreover, it was shown that cosmic-ray instruments, that use different detection techniques and are placed in different locations, can be cross-calibrated via their radio extensions. These results show the prospects of application of the radio technique for future large-scale experiments for cosmic-ray and neutrino detection. For the time being Tunka-Rex has ceased active measurements and focuses on the data analysis and publication of corresponding software and data in an open-access data center with online analysis features. In this report we present the current status of the array and give an overview of the results achieved during these years as well as discuss upcoming improvements in instrumentation and data analysis, which can be applied for the future radio arrays.

Mining enterprises are energy intensive facilities. The capacity of single technological units can reach 5 MW. Variable-frequency drive systems are often used to set them in motion. The paper analyzes the features of choosing and using variable-frequency drives under diamond mining conditions. The study objective is to formulate and formalize the problems of introducing and operating variable-frequency drives at diamond-mining enterprises to further develop and implement guidelines for improving the performance of this drive type. To achieve this objective, the use of variable frequency drives in various process units of diamond mining should be studied and analyzed. The units are considered, for which in recent years, electric drive systems have been groundlessly (according to the authors) chosen by the engineering staff of enterprises. A technical and economic comparison of low-voltage frequency converters with the same power but different control modes is performed. The economic indicators of introducing high-voltage and low-voltage frequency converters into an existing electric drive system are calculated and represented as a comparative table. Conclusions are made on the need to proceed with the research and develop guidelines for implementing frequency converters at diamond-mining enterprises.

Sparse digital antenna arrays constitute a promising detection technique for future large-scale cosmic-ray observatories. It has recently been shown that this kind of instrumentation can provide a resolution of the energy and of the shower maximum on the level of other cosmic-ray detection methods. Due to the dominant geomagnetic nature of the air-shower radio emission in the traditional frequency band of 30 to 80 MHz, the amplitude and polarization of the radio signal strongly depend on the azimuth and zenith angle of the arrival direction. Thus, the estimation of the efficiency and subsequently of the aperture of an antenna array is more complex than for particle or Cherenkov-light detectors. We have built a new efficiency model based on utilizing a lateral distribution function as a shower model, and a probabilistic treatment of the detection process. The model is compared to the data measured by the Tunka Radio Extension (Tunka-Rex), a digital antenna array with an area of about 1 km$^2$ located in Siberia at the Tunka Advanced Instrument for Cosmic rays and Gamma Ray Astronomy (TAIGA). Tunka-Rex detects radio emission of air showers using trigger from air-Cherenkov and particle detectors. The present study is an essential step towards the measurement of the cosmic-ray flux with Tunka-Rex, and is important for radio measurements of air showers in general.

Scenarios for the development of the energy complex of one of the regions of the North-East of Russia for the period up to 2030 with a target vision up to 2050 are discussed. The current state of the energy complex is analysed. The latest changes in the power supply system of the Western Energy Region of the Republic of Sakha (Yakutia) are shown, associated with the appearance of a ring circuit with four nodal substations. The advantages for the organization of the ring power supply circuit are indicated. Prospective directions for the transfer of electricity from the Republic and back are proposed. The strategic and moderate scenarios for the development of the energy sector of the Republic of Sakha (Yakutia) are assessed in modern conditions, taking into account the increase in the energy efficiency of the region’s economy. The indicators of electricity consumption throughout the Republic, the Western Energy Region and the decentralized power supply zone were evaluated. The obtained long-term forecasts do not confirm the development of events according to a more stringent strategic scenario. At the same time, the results for the moderate scenario are fully correlated with both the current state of the energy sector and the prospects for its development.

The Tunka Radio Extension (Tunka-Rex) is a digital antenna array (63 antennas distributed over 1km^2) co-located with the TAIGA observatory in Eastern Siberia. Tunka-Rex measures radio emission of air-showers induced by ultra-high energy cosmic rays in the frequency band of 30-80 MHz. Air-shower signal is a short (tens of nanoseconds) broadband pulse. Using time positions and amplitudes of these pulses, we reconstruct parameters of air showers and primary cosmic rays. The amplitudes of low-energy event (E<10^17 eV) cannot be used for successful reconstruction due to the domination of background. To lower the energy threshold of the detection and increase the efficiency, we use autoencoder neural network which removes noise from the measured data. This work describes our approach to denoising raw data and further reconstruction of air-shower parameters. We also present results of the low-energy events reconstruction with autoencoder.

Digital radio arrays are widely used for the low-frequency radio astronomy as well as for detection of air-showers induced by high-energy cosmic rays and neutrinos. Since the radio emission from air-showers forms short broadband pulses with duration of tens nanoseconds, the data acquisition strategies of cosmic-ray and astronomical arrays have significant differences. To perform precise measurement of cosmic rays, the radio array should have absolute amplitude calibration and record the entire electric field on the antenna in the broad frequency range. These requirements are similar to ones defined for the experiments aimed at the detection of weak signal from neutral hydrogen at redshifts of $z$>10, what led us to the application of our experience with Tunka-Rex to this problem. We are developing new experimental setup comprising of four antenna stations, placed on the area of 100 sq.m. Each antenna station consists of two perpendicular loop antennas measuring electric field in the frequency band of 30-80 MHz. The setup records electric fields from all antennas in portions of 50 $\mu$s reaching the spectral resolution of 20 kHz. We expect a flow of redundant data of about 10 GB/day, and plan to exploit this redundancy in order to decrease systematic uncertainty of the measurements by application of digital beam-forming, matched filtering and RFI suppression with neural networks. In the present contribution we describe the design and calibration of the setup, expected performance and data analysis techniques.

THE PURPOSE. To analyze scenarios for the development of the energy complex of one of the regions of the North-East of Russia for the period up to 2030 with a target vision until 2050. This will require an analysis of the current state of the energy complex; show the latest changes in the power supply system; propose promising areas for the transfer of electricity. METHODS. To assess the current state of the electric power industry, from the point of view of the most efficient use of natural energy resources and the potential of the energy sector of the economy, methods of collecting and processing statistical data were applied. For the technical assessment of the state of electric power facilities, analytical and logical- probabilistic methods for determining reliability were applied. To predict energy consumption, mathematical modeling methods were used with the construction of approximating polynomials. RESULTS. The article evaluates the strategic and moderate scenarios for the development of the energy sector of the Republic of Sakha (Yakutia) in modern conditions, taking into account the increase in the energy efficiency of the region's economy. The indicators of electricity consumption throughout the republic, the Western Energy District and the decentralized power supply zone were subject to assessment. Long-term forecasts made do not confirm the development of events according to a more stringent strategic scenario. At the same time, the results for the moderate scenario are fully correlated with both the current state of the energy sector and the prospects for its development. CONCLUSION. Analysis of the current state and assessment of scenarios for the development of the energy sector of the republic's economy showed an increase in the reliability of power supply systems when organizing a "ring" in the Western Energy District; increase in useful electricity consumption by 2030; increase in electricity production; changes in the structure of electricity production.

The paper deals with the influence of the type of membership functions of fuzzy variables on transient processes in an electric drive. The membership functions of fuzzy variables of S-shaped type and triangular type are proposed for consideration. To identify the dependencies of the influence of these functions, the article offers simulation modeling in the Matlab software environment, the Simulink application. The system of frequency converter - asynchronous motor (FC-AM) was chosen as the considered control system. Transient processes in the considered system with various types of membership functions are shown. The results of the work are summarized in the conclusions.

Tunka-Rex is a digital antenna array for measuring the radio emission from air-showers, induced by high-energy cosmic rays. The array started operation in 2012 with 18 antennas and had significantly developed over the years, finishing measurements in 2019 with 63 antennas and upgraded data acquisition. Analysis and processing of the collected data is a complex procedure which contains a number of steps (monitoring of state of the array, low-level filtration, quality cuts, reconstruction of air-shower parameters etc.). We give an overview of software developed for these tasks and our experience gained during the work with Tunka-Rex data. The legacy of software and data is discussed in the frame of the FAIR (Findability – Accessibility – Interoperability – Reuse) concepts.