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Purpose. The purpose of the work is to ensure the improvement of the regulation quality of pulsed energy converters with simultaneous exclusion of undesirable dynamic modes from its dynamics. Construction of a simulation model of a bridge converter with phase control and soft switching operating on an arc load, studying static and dynamic characteristics, analyzing static and dynamic modes of a closed current stabilization system, studying the nonlinear dynamic properties of the considered converter with PWM, comparative analysis of the frequency characteristics of a real closed pulse system with the characteristics of its linear model. Methodology. Fundamental principles of feedback theory, frequency analysis of electrical circuit stability and control, mathematical modeling and spectral analysis of processes in nonlinear discrete systems, digital signal processing and experimental determination of characteristics and parameters of automatic control systems. The use of engineering techniques and universal computer programs based on new solutions of the matrix equations of circuits, which allow to perform time-consuming calculations of frequency characteristics that take into account the nonlinear nature of processes in closed modern high-power pulse systems at a qualitatively different level. Findings. The proposed current control system based on a converter with soft switching transistors has sufficient reliability and service life, allows to obtain high efficiency as well as quality and accuracy indicators in conditions of uncertainty of object parameters and disturbances. A technique has been developed for designing the Bode-optimal frequency characteristics of the loop gain of the considered converter with PWM, in the possibility of controlling the static and choosing the dynamic instability of the output current, in ensuring stable operation and eliminating the self-oscillating mode of the stabilized converter operating on an arbitrary complex load. Originality. The theory of frequency control has been further developed by extending it to a new class of objects — power sources for electrical technologies with improved quality and accuracy indicators, which makes it possible to raise welding technologies and related technologies to a higher level, to solve many problems, including the problem of improving the final product quality. Practical value. The analysis of static and dynamic characteristics considered in the article and the use of new methods for calculating and measuring the equivalent frequency characteristics of converting devices with PWM should be considered as one of the stages of creating engineering methods for synthesizing power supply regulators, considering the latter as essentially nonlinear systems and taking into account the possibility of undesirable dynamic modes . The closed-loop method allows to determine the frequency characteristics of the loop gain function of a PWM converter that adequately reflects the stability conditions and possible lasing modes.

The paper discusses the use of the combined control for a system of two parallel pumps to increase its service life. Using the combined control, the pumping system is controlled together by change the speed, throttling, and bypass. The power consumption of the pumping system is calculated for three methods of flow control: with minimum energy consumption, with maximum reliability, and control with a trade‐off between efficiency and reliability. In the case of control with maximum reliability, the energy consumption of the pumping system is higher than in the case of control with minimum energy consumption by 29.2%. In the case of the proposed trade‐off control, which provides acceptable reliability, the power consumption is higher than with the minimum energy consumption control by only 7.3%. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. Funding: The work was partially supported by the Ministry of Science and Higher Education of the Russian Federation (through the basic part of the government mandate, Project No. FEUZ‐2020‐ 0060).

The rapid development of electrical engineering industries for aviation has resulted in a gradual transition to the autonomous electrohydraulic drives, among which an electro-hydrostatic drive is currently considered to be the most advanced. However, high requirements for dynamic parameters of modern unstable and low-stability aircrafts put restriction on implementation of electro-hydrostatic drives in the industry.A combined control hydraulic drive arisen from the electro-hydrostatic drive development solves the problem of low dynamic parameters. High dynamics for combined control is achieved through the use of double (throttle and electric power) control with each of them being predominant depending on the input signal value.Due to small knowledge of the drive with combined control, the article proposes to use a multi-criterion optimization method in order to obtain optimal results in its development. This will allows an adequate estimate of drive performance for its comparison with analogues and a justification of the feasibility of further research as well.The article describes all the stages of multi-criteria optimization of the combined control drive using the LP-search method. Optimization is carried out taking into account the requirements for modern aircrafts. As criteria, were taken three values , which, in the authors' opinion, provide the most complete description of the entire drive quality (a drive power consumption in the "neutral", an efficiency of the hydraulic part of the drive in the mode of electric power control, a value of ITAE when driving with a small signal). As a result of optimization, the Pareto front was obtained in three coordinates, corresponding to effective solutions, after which a compromise between the criteria was found, and the optimal solution was chosen.The design solution of the combined control drive, obtained after optimization, meets all the requirements for modern aircrafts and has both the high power performance and the high dynamics. Nevertheless, this study should be considered incomplete because of not taking into account a number of parameters, including weight-size and drive reliability ones.

Purpose. The purpose of the work is to ensure the improvement of the regulation quality of pulsed energy converters with simultaneous exclusion of undesirable dynamic modes from its dynamics. Construction of a simulation model of a bridge converter with phase control and soft switching operating on an arc load, studying static and dynamic characteristics, analyzing static and dynamic modes of a closed current stabilization system, studying the nonlinear dynamic properties of the considered converter with PWM, comparative analysis of the frequency characteristics of a real closed pulse system with the characteristics of its linear model.Methodology. Fundamental principles of feedback theory, frequency analysis of electrical circuit stability and control, mathematical modeling and spectral analysis of processes in nonlinear discrete systems, digital signal processing and experimental determination of characteristics and parameters of automatic control systems. The use of engineering techniques and universal computer programs based on new solutions of the matrix equations of circuits, which allow to perform time-consuming calculations of frequency characteristics that take into account the nonlinear nature of processes in closed modern high-power pulse systems at a qualitatively different level.Findings. The proposed current control system based on a converter with soft switching transistors has sufficient reliability and service life, allows to obtain high efficiency as well as quality and accuracy indicators in conditions of uncertainty of object parameters and disturbances. A technique has been developed for designing the Bode-optimal frequency characteristics of the loop gain of the considered converter with PWM, in the possibility of controlling the static and choosing the dynamic instability of the output current, in ensuring stable operation and eliminating the self-oscillating mode of the stabilized converter operating on an arbitrary complex load.Originality. The theory of frequency control has been further developed by extending it to a new class of objects — power sources for electrical technologies with improved quality and accuracy indicators, which makes it possible to raise welding technologies and related technologies to a higher level, to solve many problems, including the problem of improving the final product quality.Practical value. The analysis of static and dynamic characteristics considered in the article and the use of new methods for calculating and measuring the equivalent frequency characteristics of converting devices with PWM should be considered as one of the stages of creating engineering methods for synthesizing power supply regulators, considering the latter as essentially nonlinear systems and taking into account the possibility of undesirable dynamic modes . The closed-loop method allows to determine the frequency characteristics of the loop gain function of a PWM converter that adequately reflects the stability conditions and possible lasing modes., Цель работы. Обеспечение повышения качества регулирования импульсных преобразователей энергии с одновременным исключением из его динамики нежелательных динамических режимов. Построение имитационной модели мостового преобразователя с фазовым управлением и мягким переключением, работающего на дуговую нагрузку, исследование статических и динамических характеристик, анализ статических и динамических режимов функционирования замкнутой системы стабилизации тока, изучение нелинейных динамических свойств рассматриваемого преобразователя с ШИМ, сравнительный анализ частотных характеристик реальной замкнутой импульсной системы с характеристиками её линейной модели.Методы исследования. Фундаментальные принципы теории обратной связи, частотного анализа устойчивости электрических цепей и управления, математического моделирования и спектрального анализа процессов в нелинейных дискретных системах, цифровой обработки сигналов и экспериментального определения характеристик и параметров систем автоматического управления. Применение инженерной методики и универсальной компьютерной программы, базирующихся на новых решениях матричных уравнений цепей, позволяющих на качественно ином уровне в автоматическом режиме выполнять трудоёмкие расчёты частотных характеристик, учитывающих нелинейный характер процессов в замкнутых современных мощных импульсных системах.Полученные результаты. Предложенная система регулирования тока на основе преобразователя с мягкой коммутацией транзисторов обладает достаточной надёжностью и сроком службы, позволяет получить высокий КПД и показатели качества и точности в условиях неопределённости параметров объекта и возмущений. Разработана методика проектирования оптимальных по Боде частотных характеристик петлевого усиления рассматриваемого преобразователя с ШИМ, в возможности регулирования статической и выборе динамической нестабильности выходного тока, в обеспечении устойчивой работы и исключения автоколебательного режима стабилизированного преобразователя, работающего на произвольную комплексную нагрузку.Научна новизна. Получила дальнейшее развитие теория частотного управления путём её распространения на новый класс объектов – источники питания для электротехнологий с улучшенными показателями качества и точности, что позволяет поднять сварочные и смежные с ней технологии на более высокий уровень, решить многие проблемы, в том числе проблему улучшение качества конечного продукта.Практическая ценность. Рассмотренные в статье анализ статических и динамических характеристик и применение новых методик расчёта и средств измерения эквивалентных частотных характеристик преобразовательных устройств с ШИМ следует считать как один из этапов создания инженерных методик синтеза регуляторов источника питания, рассматривающий последние как существенно нелинейные системы и учитывающих возможность возникновения нежелательных динамических режимов. Метод замкнутого контура позволяет определить частотные характеристики функции петлевого усиления преобразователя с ШИМ, адекватно отображающие условия устойчивости и возможные режимы генерации., Мета роботи. Забезпечення підвищення якості регулювання імпульсних перетворювачів енергії з одночасним виключенням з його динаміки небажаних динамічних режимів. Побудова імітаційної моделі мостового перетворювача з фазовим керуванням і м'яким перемиканням, що працює на дугове навантаження, дослідження статичних і динамічних характеристик, аналіз статичних і динамічних режимів функціонування замкнутої системи стабілізації струму, вивчення нелінійних динамічних властивостей розглянутого перетворювача з ШІМ, порівняльний аналіз частотних характеристик реальної замкнутої імпульсної системи з характеристиками її лінійної моделі.Методи дослідження. Фундаментальні принципи теорії зворотного зв'язку, частотного аналізу стійкості електричних ланцюгів і управління, математичного моделювання та спектрального аналізу процесів в нелінійних дискретних системах, цифрової обробки сигналів і експериментального визначення характеристик і параметрів систем автоматичного управління. Застосування інженерної методики та універсальної комп'ютерної програми, що базуються на нових рішеннях матричних рівнянь ланцюгів, що дозволяють на якісно іншому рівні в автоматичному режимі виконувати трудомісткі розрахунки частотних характеристик, що враховують нелінійний характер процесів в замкнутих сучасних потужних імпульсних системах.Отримані результати. Запропонована система регулювання струму на основі перетворювача з м'якою комутацією транзисторів володіє достатньою надійністю і терміном служби, дозволяє отримати високий ККД і показники якості і точності в умовах невизначеності параметрів об'єкта і збурень. Розроблено методику проектування оптимальних за Боде частотних характеристик петлевого посилення розглянутого перетворювача з ШІМ, в можливості регулювання статичної та виборі динамічної нестабільності вихідного струму, в забезпеченні стійкої роботи і виключення автоколивального режиму стабілізованого перетворювача, що працює на довільне комплексне навантаження.Наукова новизна. Отримала подальший розвиток теорія частотного управління шляхом її поширення на новий клас об'єктів - джерела живлення для електротехнологій з поліпшеними показниками якості і точності, що дозволяє підняти зварювальні та суміжні з нею технології на більш високий рівень, вирішити багато проблем, в тому числі проблему поліпшення якості кінцевого продукту.Практична цінність. Розглянуті в статті аналіз статичних і динамічних характеристик і застосування нових методик розрахунку і засобів вимірювання еквівалентних частотних характеристик перетворювальних пристроїв з ШІМ слід вважати як один з етапів створення інженерних методик синтезу регуляторів джерела живлення, який би розглядав останні як істотно нелінійні системи і враховуючи можливість виникнення небажаних динамічних режимів. Метод замкнутого контуру дозволяє визначити частотні характеристики функції петлевого посилення перетворювача з ШІМ, адекватно відображаючи умови стійкості та можливі режими генерації.

In order to mitigate the excessive longitudinal displacement responses of suspension bridge girders induced by vehicle braking force, as one of the possible dynamic loadings, a combined control strategy consisting of viscous dampers and friction pendulum bearings is developed in this paper. Firstly, the vehicle composition and the braking force models of the Pingsheng Bridge are obtained by traffic survey and testing results, respectively. Then, the vibration response analysis for the bridge under the braking force is implemented using the MIDAS finite element model. Furthermore, viscous dampers and friction pendulum bearings are separately employed to reduce the vibration responses. The influence matrix method is first used to determine the optimal parameters of viscous dampers. Finally, the effect of the combined control strategy for the vibration control is investigated. The numerical analysis results indicate that utilizing the influence matrix method for the parameter optimization of viscous dampers is feasible and effective. It is also shown that the longitudinal displacement response of the Pingsheng Bridge subjected to the vehicle braking force can be effectively mitigated by viscous dampers, friction pendulum bearings or the combined control with the optimized parameters, and the combined control outperforms the viscous dampers or the friction pendulum bearings alone.

Розглядається актуальна задача структурного синтезу системи автоматичного управління індивідуальним тепловим пунктом житлових, виробничих і офісних будівель. На основі спрощеної математичної моделі процесу теплопостачання, що відбиває в безрозмірною формі основні конструктивні параметри будівлі, за допомогою принципу максимуму знайдений оптимальний закон керування тепловою потужністю з урахуванням короткострокового прогнозу погоди. Отримане програмне управління з обуренню коригується управлінням по відхиленню температури приміщення від заданого комфортного значення., The actual problem of structural synthesis of the automatic control system for the thermal state of housing, industrial and office buildings is considered. Based on the simplified mathematical model of the main thermal processes of the heated building and short-term weather forecast, the method and algorithm of the thermal power optimal control the were developed based on the criterion of the internal air temperature minimum deviation from the specified comfort value. The application of the maximum principle and the numerical method of fixed-point iterations for solving the two-point boundary problem allowed to find the thermal power software control online, which corresponds to the ideology of the MPC method. Program control errors caused by the inaccuracy of the mathematical model and the weather forecast is proposed to compensate in control circuit by the deviation of the actual internal temperature from its comfort value. The corresponding block diagram of the combined control system is proposed., Рассматривается актуальная задача структурного синтеза системы автоматического управления индивидуальным тепловым пунктом жилых, производственных и офисных зданий. На основе упрощенной математической модели процесса теплоснабжения, отражающей в безразмерной форме основные конструктивные параметры здания, с помощью принципа максимума найден оптимальный закон управления тепловой мощностью с учетом краткосрочного прогноза погоды. Полученное программное управление по возмущению корректируется управлением по отклонению температуры помещения от заданного комфортного значения.

Обоснована актуальность работы. Проведен обзор и анализ информации о существующих протезах и системах управления. Анализ известных аналогов зарубежных и отечественных фирм-производителей. Выбран прототип и обосновано данное решение. Выбрана и разработана система управления. Произведен расчет мощности и выбор двигателя. Решены основные инженерные вопросы построения протеза. Спроектирован миотонический датчик. Обеспечено пропорциональное управление. Разработаны принципиальные и конструктивные схемы протеза., The relevance of the work was substantiated. A review and analysis of the existing dentures and control systems. Analysis of the known analogues of foreign and domestic manufacturers. Selected prototype and justified this decision. Selected and designed control system. The calculation of power and engine choice. Solved the main engineering issues of building the prosthesis. Designed myotonic sensor. Provided proportional control. Developed basic and structural scheme of the prosthesis.

K.Ya. Shabo, kamilshabo@rambler.ru Technical Institute (Branch) of M.K. Ammosov North-Eastern Federal University, Neryungri, Russian Federation Шабо Камил Якуб, канд. техн. наук, доцент, кафедра «Электропривод и автоматизация производственных процессов», Технический институт (филиал) ФГАОУ ВПО «Северо-Восточный федеральный университет им. М.К. Аммосова», г. Нерюнгри; kamilshabo@rambler.ru. Показано, что в целях экономии электроэнергии важную роль играют микропроцессорные системы управления, в основе которых – задающие модели с выходными сигналами, изменяющимися пропорционально диаграммам перемещения, скорости, ускорения (тока), а также производной ускорения во времени (рывка). Автором разработана общая задающая модель второго порядка с тремя выходными сигналами, пропорциональными заданным значениям скорости, ускорения и рывка или положению, скорости и ускорению. Задающая модель построена на базе интегрирующих звеньев и релейных устройств с учетом внутренней обратной связи двигателя, позволяющей формировать оптимальные законы изменения управляемых координат, что облегчит реализацию ограничения производной тока якоря без специального регулятора производной тока, применение которого усложняет настройку системы и повышает ее чувствительность к параметрическим возмущениям. The microprocessor control systems based on the setting models with outputs changing proportionally to the diagrams of displacement, rate, acceleration (current) and derivate acceleration in time (jerk) play an important role in power saving. The authors have developed a general second-order model with three output signals proportional to the set values of speed, acceleration and jerk or to position, velocity and acceleration. This setting model is based on integral units and relay gears considering internal motor feedback. They enable development of optimum patterns of controlled coordinate change and facilitate implementation of the limits of the derivative of the armature current without a special controller of the current derivative, which complicates the system configuration and increases its sensitivity to parametric changes.

To optimize the structure of multicell-type transistor converter with combined control it is proposed to use an additive criterion, wich would take into account such particular criteria as efficiency, cost and construction volume of the converter.

В данной статье рассматривается вопрос изменения нагрузки действующих энергоблоков тепловых электростанций, имеющих турбины с сопловым парораспределением, путем применения комбинированной программы регулирования и определение эффективности использования режима скользящего давления в зависимости от различного количества открытых регулирующих клапанов и начальных параметров пара. This paper gives consideration to the problem of a change of the load of the working energy blocks of thermal power stations that have turbines with steam distribution nozzles, using the combined control program and defining the efficiency of the use of sliding pressure mode depending on a different number of open control valves and initial steam parameters. The analysis of the test data and computational data showed that it is more preferable to use the combined control program switching over the energy block into the sliding pressure mode and fully opening the three valves for the turbines with supercritical parameters whose steam distribution structure has four control valves and each valve services its nozzle group; for operating turbines K-200-130 and K-160-130 that have two completely open valves the combined control program is considered to be more efficient; one of the promising ways of an increase in the efficient operation of the turbine plant with the combined control program can be the modernization of the control stage with the realization of its maximum efficiency in the mode close to nominal.

This paper proposes an online test technique that employs mixed control of displacement and force. Two types of mixed control, ‘displacement–force combined control’ and ‘displacement–force switching control’ are proposed. In displacement–force combined control, one jack is operated by displacement-control, and another is operated by force-control. Validity of the combined control technique is demonstrated by a series of online tests applied to a base-isolated structure subjected to horizontal and vertical ground motions simultaneously. The substructuring technique is employed in the tests, and the base-isolation layer is tested, with the rest of the structure modeled in the computer. Displacement-control and force-control were adopted for simulating the horizontal and vertical response, respectively. Both displacement- and force-control were implemented successfully despite interference between the two jacks. Earthquake responses of the base-isolated structure involving the effects of varying axial forces on the horizontal hysteretic behavior of the base-isolation layer were simulated. In the displacement–force switching control, the jack was operated by displacement-control when the test specimen was flexible but switched to force-control once the specimen became stiff. Validity of the switching control technique was also checked by a series of online tests applied to the base-isolated structure subjected to vertical ground motions. Switching between displacement-control and force-control was achieved when the axial force applied to the base-isolation layer changed from tension to compression or from compression to tension. Both the displacement- and force-control were successful even with many rounds of switching. The test revealed that large accelerations occurred on the floor immediately above the base-isolation layer at the instants when the axial force of the base-isolation layer changed from tension to compression. Copyright © 2005 John Wiley & Sons, Ltd.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES This work proposes an algorithm that combines two control laws with di erent compensation characteristics in order to obtain a robust and high performance control: A Linear Quadratic Regulator aided by a Kalman lter or LQRKF and a Robust Model Reference Adaptive Controller or RMRAC. The design of each used controller is performed independently and the combined algorithm is composed by the sum of the two separated control laws. The main motivation for the union of these two strategies is to obtain an algorithm that carries the properties of each controller involved. The RMRAC scheme is designed to ensure robustness against parametric variations and unmodeled dynamics, while the LQRKF regulator is designed to reduce the distortion e ects caused by the voltage at the Point of Common Coupling or PCC. Moreover, the LQRKF controller presents a fast transient response. The combined control structure ensures a proper tracking performance, considering di erent types of adversities, commonly found in real systems, such as high line impedance, noise measurement, frequency variation of network, unbalance of currents, among others. Moreover, it is developed the stability proofs of the proposed control system, from a candidate Lyapunov function. It is also shown the robustness of the control system, since regarded the design constraints. Finally, in order to verify the consistency of the proposal, extensive tests, simulation and experimental results are presented, by implementing the control system using a Digital Signal Controller or DSC for the control of a power conditioner comprising a shunt three-phase PWM inverter connected to the network through an inductive coupling lter. Este trabalho prop~oe um algoritmo que combina duas leis de controle com diferentes caracter sticas de compensa c~ao a m de se obter um sistema de controle robusto e de elevado desempenho: Um Regulador Linear Quadr atico auxiliado por um Filtro de Kalman ou LQRKF (do ingl^es Linear Quadratic Regulator based on Kalman Filter ) e um Controlador Adaptativo Robusto por Modelo de Refer^encia ou RMRAC (do ingl^es Robust Model Reference Adaptive Controller ). O projeto de cada controlador utilizado e realizado de forma independente e a lei de controle combinada e resultado da soma das duas leis de controle calculadas. A principal motiva c~ao para uni~ao destes dois controladores e obter uma lei de controle que apresente as propriedades de cada compensador envolvido. O algoritmo RMRAC e desenvolvido de forma a garantir robustez frente a varia c~oes param etricas do sistema e din^amicas n~ao modeladas, enquanto que o regulador LQRKF e projetado para reduzir os efeitos causados pela distor c~ao de tens~ao no Ponto de Acoplamento Comum ou PCC (do ingl^es Point of Common Coupling). Al em disso, o controlador LQRKF apresenta uma r apida resposta transit oria. Esta estrutura de controle combinado garante um r apido e apropriado desempenho quanto ao rastreamento das refer^encias, considerando diferentes tipos de adversidades, comumente encontradas em sistemas reais, tais como alta imped^ancia de linha, ru dos de medida, varia c~ao de frequ^encia da rede, desequil brio de corrente, entre outros. Al em disso, e desenvolvida a prova de estabilidade em tempo discreto do sistema de controle proposto, a partir de uma fun c~ao candidata de Lyapunov. Tamb em e mostrada a garantia de robustez do sistema de controle, desde que atendidos os requisitos de projeto. Ao nal, de forma a veri car a coer^encia da proposta, extensivos testes, resultados de simula c~ao e experimentais s~ao apresentados, implementando-se o sistema de controle utilizando um controlador digital de sinais DSC (do ingl^es Digital Signal Controller ) para controle de um condicionador de pot^encia formado por um inversor PWM trif asico, conectado em paralelo com a rede atrav es de um ltro de acoplamento indutivo.

Предложена математическая модель и структурная схема следящего электропривода с комбинированным управлением. Выполнено моделирование привода для различных режимов обработки. A mathematical model and flow diagram of servo electrodrive with the combined control is offered. Designing of the drive is got up for different modes of working.