## No 31 (2019)

**Year:**2019**Articles:**11**URL:**https://ered.pstu.ru/index.php/elinf/issue/view/221**DOI:**https://doi.org/10.15593/.v0i31

Articles

IMITATION MODEL OF A DIGITAL PHASE-SHIFTING DEVICE WITH INCREASED TIME RESOLVING CAPABILITY

#### Abstract

The functioning of shipboard electrical equipment is closely related with the quality of electrical energy. Changing the frequency of the alternating current leads to a change in the operating modes of electrical systems in the ship electric power system. In particular, to a decrease in the performance of pumps and fans, to a interruption of the stability of the generators and turbines of the electricity power station and to a decrease in the overload capacity of induction motors. The influence of the frequency change introduces in the regulation of the moments commutation to the semiconductor valves. Pulses of control formed by phase-shifting devices of the rectifier control system. As a result, there is a deterioration in the quality of the regulatory process and a change in static and dynamic characteristics, as well as the possibility of dangerous situations for process equipment. The digital phase-shifting device with a memory unit was developed for stabilize the output parameters of the semiconductor converter. This device allows to correct the commutating moments of the semiconductor gate depending on the frequency of the alternating current. The purpose of this work is to analyze the functioning of various types of phase-shifting devices based on the static and dynamic characteristics of the relative error of average rectified voltage depending on the voltage frequency and the angle of control. To study the proposed device, a series of experiments was carried out on the basis of a simulation model in the MatLab environment. The processing of the results obtained during the study of the simulation model proposed by the digital phase-shifting device as part of a three-phase rectifier with asymmetric control together with the prototype device is presented. The results of the analysis showed the possibility of using the device with resistance to instability of changes in the frequency of the supply network as part of a three-phase rectifier in order to reduce the deviation of the rectified voltage and smoothly change the angle of control for powering DC consumers in ship power systems. The technical result of the developed device is to increase the time resolution in contrast to the device prototype.

**PNRPU Bulletin. Electrotechnics, Informational Technologies, Control Systems**. 2019;(31):6-21

GROUP VOLTAGE CONTROL MODELING WITH SOURCES OF ACTIVE AND REACTIVE POWER IN ELECTRICAL NETWORKS

#### Abstract

The introduction of generation sources and adjustable reactive power compensation devices in distribution electric networks of railways requires the development of new methods of group voltage control, for example, based on an agent-based approach. Multi-agent voltage management allows to obtain new results related to the possibility of self-organizing agents-active elements of the electrical network, which leads to an increase in the reliability of power supply and power quality. Modeling the considered multi-agent control systems on classical models of system dynamics is difficult because of the complex interaction of agents due to their individual utility goals, the presence of logical operations and the event-driven nature of the processes. A significant part of publications on multi-agent control of electric network modes, including those with elements of distributed generation, energy storages, is devoted to the development of concepts and subsystems of such management, in which the simulation results are presented for individual components. The implementation of the approach based on a combination of traditional methods of system dynamics and agent-based modeling will solve these problems. The principles of coordination of local agents of power sources of the type “auction” and expressions for determining control actions based on the sensitivity of voltages in the electrical network nodes to power injections are presented. Agent state diagrams have been developed for modeling multi-agent voltage control using reactive power sources in distribution electrical networks of railways in the Anylogic environment. The simulation of the voltage control in the test electrical network when changing the parameters of the mode. The obtained simulation results indicate the validity of approaches to voltage stabilization by multi-agent control methods and the possibility of their practical implementation on the basis of modern equipment.

**PNRPU Bulletin. Electrotechnics, Informational Technologies, Control Systems**. 2019;(31):22-34

DIAGNOSIS OF FPGA WITH NEW ELEMENTS

#### Abstract

Programmable logic integrated circuits are widely used in digital equipment, including equipment for critical applications, for example, in medicine, avionics, in control systems for spacecraft, atomic power stations, in military and special equipment. Currently, the number of logical elements in the most advanced FPGA samples is approaching tens of millions. Therefore, the diagnosis of logic FPGA responsible use is a very urgent task. This task is complicated by the fact that the number of variables increases and now there are individual elements that implement the functions of six, seven and even eight variables. We should expect a further increase in the dimension of the problem solved in a single logical element. Existing methods for diagnosing FPGA logic are based on boundary scanning using external hardware according to the IEEE 1149.1 standard, and embedded test tools are actively being implemented according to the IEEE P1500 standard. As a rule, a comparison of the results of calculations in several logical elements is used, and if the results of calculations in one of them differ from the results, for example, the group of three elements, then it is concluded that there is a fault in this separate element. All this takes a relatively long time. For some applications, this approach is unacceptable. At the same time, methods and means of self-control, as well as accelerated testing, are not fully developed. The same applies to the features of diagnosing new logical elements of the so-called “Green Logic”. Well-proven genetic algorithms require refinement to reflect these new factors in order to improve the built-in testing of FPGAs. Article investigates methods and tools for diagnosing the FPGA logic for highly reliable applications. Authors shows that advanced logical elements can improves logic reliability via diagnosis. The task is to perfect the methods for diagnosing the logic of the FPGA using new logic elements, based on genetic algorithms.

**PNRPU Bulletin. Electrotechnics, Informational Technologies, Control Systems**. 2019;(31):35-50

DEVELOPMENT OF AN IMITATION MODEL OF A MOBILE ENERGY COMPLEX ON THE BASIS OF RES IN MATLAB PROGRAM

#### Abstract

In article the problem of high-quality and uninterrupted power supply of the decentralized zones of the Russian Federation rises. Today, this problem is one of the most important and priority problems of domestic power. Authors of this article considered a question of electricity supply of such consumers by means of a mobile scalable energokompleksan on the basis of renewable power sources. Given solutions is the most reasonable, "The separate perspective task is a development of renewable energy resources, especially in the remote, hardly accessible regions of our country, such as Eastern Siberia, the Far East. For our extensive, the biggest in the world on the territory of the country with its various natural, climatic conditions really huge opportunity opens here" - V.V. Putin at the International forum "Russian Power Week" which took place on October 3, 2018 in Moscow noted. The main contents of article are directed to creation and the analysis of model of a mobile power complex in software environment of MatLab. The model of a power complex will consist of several elements: the wind generator, photo-electric panels, diesel power station and rechargeable batteries which will be created by means of block maps. For the analysis of model random initial data were entered: meteorological parameters; number and capacity of rechargeable batteries; area of solar modules; diagram of loadings; wind generator power. The theoretical place of testing of model it was accepted by Roshchino of Primorsky Krai. The diagrams removed from oscillographs are result of tests. Having investigated, these diagrams can be made the conclusion that the model is constructed truly. The practical importance of creation of this model is not only acceleration of process of creation of real model of a mobile energokomplesks, but also will help developers to pick up the most optimum parameters of power sources.

**PNRPU Bulletin. Electrotechnics, Informational Technologies, Control Systems**. 2019;(31):51-71

MATHEMATICAL MODELLING OF DYNAMICS OF ELECTRICAL MACHINES IN-PHASE AXES

#### Abstract

In the article on the example of synchronous generator the description of dynamic mathematical model of electric machine is considered. This mathematical description is presented in the natural three-phase coordinate system a,b,c. The advantages and disadvantages of this description are shown. On the example of a synchronous generator, a General form of recording for an arbitrary element of the electrical system is obtained. This form of recording is obtained in vector-matrix form. In such a General form of recording it is advisable to present all the main elements of the electrical system (generators, electric motors, electric load elements, power lines, etc.) in order to be able to model them together within a single electrical system. It is shown that in this mathematical description of the inductance of the electric machine depends on the position of the rotor. Two variants of the account of the specified dependence are considered: by means of analytical expressions and by means of matrix transformations. Modern computer technology does not encounter any difficulties in mathematical modeling of electric machines directly in the natural three-phase coordinate system. The widespread use of the transformed two-phase coordinate system can be largely explained by tradition. Description of electrical machines in the axes a,b,c seems particularly appropriate in the study of asymmetric modes of operation in electrical systems and the asymmetric design of the electric machine. This article is the first article. Following it in the next article will be considered modeling of interaction of electric machines and other elements among themselves within the framework of a single electrical system. Mathematical models considered in the article can be used to study dynamic processes in electrical systems. Including asymmetric dynamic processes. On the basis of the mathematical description obtained in the article, it is planned to create an original software package for modeling various dynamic modes of three-phase electrical systems.

**PNRPU Bulletin. Electrotechnics, Informational Technologies, Control Systems**. 2019;(31):72-90

THYRISTOR VOLTAGE REGULATOR APPLICATION IN RADIAL ELECTRICAL NETWORKS 6-10 kV FOR POWER FLOW CONTROL

#### Abstract

The transition to intellectual electrical networks is a crucial task of the Russian and foreign energy industry. One of the parameters of intellectualization is the ability to control the flow of power in electrical networks. It is possible to implement it with the help of devices that allow controlling the parameters and operation modes of the electrical network. This device was developed at the Nizhny Novgorod State Technical University. R.E. Alekseeva. The article is devoted to the study of the effective areas of the thyristor voltage regulator (TVR) operation in parallel operating power transmission lines (PTL), as well as to determine the dependence of efficiency factor, current and power characteristics on the value of the booster voltage. The most convenient way to solve the problems is modeling in the MatLab Simulink software package, which has high speed and the required measurement accuracy. The developed simulation TVR model allows to implement longitudinal, transverse and longitudinal-transverse voltage regulation. The introduction of this model into the studied area of the distribution electric network (DEN) allowed to conduct investigation of the power flows regulation with the application of the developed device. The area of current stabilization in parallel operating air and cable lines was determined. The operation of the device in this area allows to increase the transmission capacity of power lines and increase the network efficiency factor as a whole. In the Mathcad software package, a mathematical model of the TVR was developed. Using the method of nodal potentials, the dependences of various parameters of the DEN of the studied area were obtained. The analysis of the characteristics has shown that the introduction of the device into the radial DEN with parallel operating power lines will increase the efficiency of power transmission to consumers.

**PNRPU Bulletin. Electrotechnics, Informational Technologies, Control Systems**. 2019;(31):91-105

ASSESSMENT OF STOCHASTIC PROPERTIES OF EQUIVALENT PERTURBATION EFFECTS IN DIRECT-FLOW POWER CONTROL SYSTEM POWER PLANT UNIT BOILER

#### Abstract

In modern power systems, block thermal power plants are involved in the regulation of frequency and power in normal and emergency modes. The implementation of power control tasks for power units in the mode of regulating the parameters of the power system requires the creation of special frequency and power control systems. Since the frequency and power of the power unit are interrelated, the task of maintaining the frequency at a given value is implemented by the power control system of the power unit. The article analyzes and evaluates the influence of external disturbing influences on the power control system of a once-through boiler of a block-type TPP. To date, the automatic power control system has been considered without taking into account the real nature of the disturbing influences on the load and the frequency control poses the problem of taking into account the stochastic properties of power system perturbations. In the normal operation mode, the stochastic properties of the equivalent disturbance can be determined from the results of a computational experiment using the power unit's automated process control system database. To obtain an equivalent perturbation, models were constructed for the steam pressure channel for the boiler unit and the power channel for the turbine unit, and the values of the expectation and standard deviation of the autocorrelation functions were calculated. A comparative analysis of the region of the most intense perturbing frequencies and resonant frequencies of the regulator BPR and TPC is performed. The proposed method allows to obtain a probabilistic model of the equivalent perturbation of the boiler unit and the turbine unit in normal operation. Equivalent perturbation models can be used to assess the technological effectiveness of the proposed solutions to improve the performance of the power unit control system.

**PNRPU Bulletin. Electrotechnics, Informational Technologies, Control Systems**. 2019;(31):106-120

IDENTIFICATION OF THE MATHEMATICAL MODEL OF THE AUTOMATIC CONTROL SYSTEM OF A GAS TURBINE ENGINE

#### Abstract

When creating modern aviation gas turbine engines, there is a significant complication of automatic control systems and control, and their control tasks are nontrivial for many reasons. To solve these problems, an adequate mathematical model of the automatic control system in real time is necessary. The presence of such a model creates prerequisites for solving control problems, and also makes it possible to ensure information redundancy, which allows increasing the fault tolerance of the automatic control system, that is, its ability to perform its functions after the appearance of faults. The article presents the results of the analysis of the mathematical model of the modern automatic control system of a gas turbine engine at the steady-state and one of the transient modes of operation. The analysis includes the recurrent identification of the mathematical model coefficients, the estimation of the identification accuracy and the determination of the measuring and system noise statistical characteristics. The identification was carried out on the basis of measurement information obtained as a result of flight tests of an aircraft gas turbine engine. The methods of regression and analysis of variance have been used. To determine the optimal estimates of the mathematical model coefficients, the least squares method in a moving window was used. This method allows one to obtain unbiased estimates of coefficients with minimal variance. The width of the moving window was optimized in order to ensure a minimum of the lag time for the estimates of the model output signal and the required identification accuracy in all modes of engine operation. The accuracy of identification was estimated by the coefficient of determination. The results of the automatic control system mathematical model analysis for one of the steady-state and transient modes are presented in the form of tables and graphs. It is shown that the proposed identification algorithm meets the requirements for the accuracy of determining the estimates of the output signals of the automatic control system of a gas turbine engine and their time lag.

**PNRPU Bulletin. Electrotechnics, Informational Technologies, Control Systems**. 2019;(31):121-135

EFFECTIVE ADJUSTMENT TECHNIQUE OF MATHEMATICAL MODELS OF THERMAL POWER EQUIPMENT ON ITS ACTUAL CONDITION

#### Abstract

The problems of state estimation of thermal power system operation and identification of mathematical model parameters have not been acceptable solved due to the complexity of objects of studies and their mathematical models, and the lack of effective methods, algorithms and computer programs to solve the required mathematical tasks. The results of solving the indicated problems are of importance in themselves and play a large part in the qualitative solution to thermal power units’ control problems, e.g., the tasks of optimal load distribution among the thermal power plants units and optimal control of thermal power units operating conditions. The current thermal power units, such as boiler units and steam turbines, are technical systems with rather complex engineering flow diagrams, diverse elemental composition and operation conditions. Hence, the main instruments to study thermal power equipment are the methods of mathematical modeling and optimization of its schemes and parameters. The paper describes a description an improved technique for identification (adjustment) of mathematical models for current main thermal power equipment. The technique allows us to reveal more effectively the gross errors in measurements of control parameters used to identify the mathematical model of the equipment under study, evaluate the correctness and correct the errors in constructing the mathematical model itself and improve the accuracy of identification. Among other things, the article discusses the issue of assessing the accuracy of identification the parameters of mathematical models of heat and power equipment, depending on the accuracy of measurements of control parameters used to set up the model, as well as on the correctness of the construction of the mathematical model itself and the calculation method used.

**PNRPU Bulletin. Electrotechnics, Informational Technologies, Control Systems**. 2019;(31):136-158

STUDY OF THE STARTING MODES OF A SYNCHRONOUS ENGINE AT A REDUCED FREQUENCY

#### Abstract

Traditionally, the synchronous engine is started in asynchronous mode with a winding closed to additional resistance. All methods of starting an asynchronous engine can be applied to a synchronous engine. The method of starting the engine depends on its operating mode and on the magnitude of the resistance moment acting on the shaft. The article presents the results of studies on starting a synchronous engine with various parameters of the power source and the resistance moments on the engine shaft. The studies were carried out on models built in the graphical environment of simulation modeling Simulink of application package for solving of technical computing problems MATLAB. This software allows you to simulate and explore various modes of starting a synchronous engine at different values of the supply voltage and its frequency. It was investigated several options for starting a synchronous engine with excitation at various frequencies of the order of 2,5-10 Hz. The study of load conditions was carried out after a synchronous engine start with excitation in the entire frequency range. The load was thrown over a time interval of 0,2 seconds. The load power remained unchanged for different frequencies. The results of the study are presented in the form of graphs, on the basis of which conclusions are drawn. The studies of the load surge mode at various frequencies showed the possibility of synchronous start in the frequency range from 2,5 to 10 Hz. The relevance of the work lies in the fact that its results and conclusions made on their basis will allow designers of electric machines (synchronous engine) to simplify their design and calculation, as well as to identify the effect of transients on the object under study.

**PNRPU Bulletin. Electrotechnics, Informational Technologies, Control Systems**. 2019;(31):159-176

HARDWARE NEURAL NETWORKS PROGRESS ON FPGA AND ASIC

#### Abstract

The article provides a survey about the implementation of neural networks on Programmable Logic Device (PLDs) such as FPGA (Field Programmable Gate Array) and Application-Specific Integrated Circuit (ASIC) from 2009 to 2019. Advantages and restrictions of this approach are given using on various hardware platforms. The reasons for the appropriateness to use FPGAs and ASICs based on them on such or another platform are indicated. In particular, FPGAs work best in low-power mobile systems, while ASICs, being a specialized solution, demonstrate the highest possible performance with, however, the development cost too high. We compare the performance of neural networks of various architectures (perceptrons, convolutional, binarized, recurrent, and also their modifications) based on FPGA with respect to other hardware solutions according to the criteria of processing speed and power consumption in relation to the price and ease of deployment. The high interest in FPGAs is investigated and confirmed as a result of their high energy efficiency and performance in solving a number of tasks. It is shown that GPUs are best suited for the implementation of convolutional neural networks, while FPGAs are suitable for recurrent ones. We note that with binarization of neural networks, the performance of gate arrays increases significantly, approaching the performance of specialized microcircuits. A promising direction for subsequent research is to further increase the performance of binarized neural networks implemented on the basis of FPGA, by improving both the mathematical apparatus underlying the network and the internal architecture of the gate array and its logic elements.

**PNRPU Bulletin. Electrotechnics, Informational Technologies, Control Systems**. 2019;(31):177-192