Идентификация процессов судового оборудования методами интроспективного анализа

The article concerns the problem of structure-and-parametric optimization of a cascade automatic control system (CACS) by an example of a boiler power controller and a fuel controller. This CACS, which is a part of automatic control systems for power units, consists of two loops, viz. of an inner loop (which purpose is stabilization of the system) and an outer loop (designed for the adjustment) and, also, of two controller, viz. an outer controller (which is a basic one) provided for stabilization of the output value of the object (in our case, of the actual power unit capacity) and of an inner controller (which is an auxiliary one) provided to regulate fuel consumption. The internal controller builds up the control action with the aid of the boiler load controller of the power unit. As compared to single-loop automatic control systems, the cascade system provides better quality of transient control due to the higher performance of the internal loop of the system. This advantage is especially noticeable when compensating for disturbances that come through the channel of regulating impact. The article presents two methods of setting, viz. the fuel controller and the boiler power controller. The application of these methods can improve the quality of power control and reduce fuel consumption in transient modes in comparison with the setting of these controllers of a typical power unit automatic power control system. The results of computer simulation of transient processes in CACS for input step surge and internal perturbation confirm the advantages of the methods are presented in this article.

An approach is proposed for the adequate description of the processes of state change and optimization of complex discrete automatic control systems (ACS), in which the conver-sion of control signals into a sequence of pulses with time modulation is used. Requirements for actuators in many cases of practical use produce the need to use such a conversion to achieve proportional regulation of the output action in accordance with the input control sig-nal. The description of discrete automatic control systems of the specified type is generalized and an equivalent transformation of the discrete equations of their motion is proposed. The specified transformation allowed to take into account the change in the length of the control pulses for the linear continuous invariant part of the automatic control system. The proposed equivalent transformation of the equations of motion for discrete (im-pulse) systems with a constant sampling interval significantly simplifies their mathematical description and requires fewer resources for computational implementation. For automatic control systems with pulse-width modulation of the control signal, the algorithm for synthesis and obtaining the control signal has been improved, namely, the law of changing the polarity of the pulses and the form of the modulation characteristic based on the Lyapunov method. A distinctive feature of the proposed approach is the inclusion in the criteria of optimal-ity of energy costs for control in the form of a dependence on the duration of control pulses. Functional dependencies were obtained in a closed analytical form, which establish the form of the law of pulse polarity change and analytical description of the modulation characteristic of the pulse-width converter of the control signal according to the given criterion and pa-rameters of the invariable continuous part of the ACS. A computer experiment and simulation were performed when solving the test problem. The obtained results of solving the test problem confirm the effectiveness of the pro-posed approach. It was established that when using optimal nonlinear control laws, the qual-ity criterion is improved compared to the applied linear ones.

The article deals with the problem of parametric optimization of automatic control systems for power units of 300 MW of Lukoml’skaya GRES in the mode of variable pressure of turbine inlet superheated steam. The modernization of automatic power control systems of all power units of Lukoml’skaya GRES was carried out in the nineties of XX century for the last time. At the moment, these systems no longer meet all the requirements of the new standard, which regulates the participation rates of thermal power units in the normalized primary frequency control and in automatic secondary control of frequency and active power flows. According to this standard, the time to achieve the half value of the required power change should be 10 seconds within the normal and emergency reserves; the time to achieve the full value of the required power change should be 30 seconds within the normal reserve and 2 minutes within the emergency one. The construction of the Belarusian NPP is also being completed; its first unit will be put into operation in 2019, and the second one–in 2020. After the launch of the NPP, the Lukoml’skaya GRES power units will be necessitated to operate in a wide range of load changes. It is for these reasons that it is necessary to improve the efficiency of power units in particular and of the entire power plant in general. This can be achieved with the help of the outlined method of parametric optimization of a typical system of automatic control of power units, which allows improving the quality of control of turbine inlet steam power and pressure. The results of computer simulation of transient processes in the system illustrate the technique described in this article and confirm its correctness and undoubted advantages over other methods of optimization of typical systems of automatic control of power units.

The manufacturing processes complication leads to cost increasing of equipment service and maintenance costs. An important role in overcoming these factors is played by modern automatic control systems, regulators optimization and adaptation of control systems to changing conditions. Today, the actual problem remains the adjustment and optimization of automatic control systems, especially complex structures.The article researches the population optimization algorithm "Gray wolf" as applied to the search for optimal PID-controller settings. A cascade automatic control system with two PID regulators optimized for a minimum of integral IAE, ISE quality criteria, as well as control time is considered. The advantage of the method under investigation is shown in a comparing with the Hook-Jeeves zero-order optimization method. The mathematical modeling of the automatic control system of air temperature in a clean room with the “Grey wolf” optimization method is performed. Attention is focused on the convenience of using the method, since it does not require an accurate setting of the initial parameters of the regulators. This eliminates the need for an a priori knowledge of the customizable system dynamics by the user. The commissioning of control parameters optimizing systems will help to increase the efficiency of the equipment in conditions of variable operating modes. The recommended area of the method used is the complex structures of automatic control systems, where the search for optimal settings by classical methods is difficult or does not exist.

Context. In combined automatic control systems (ACS) with the principle of control by disturbance, there are difficulties in controlling disturbances in some objects of radio engineering systems and somewhat lower accuracy. This is especially noticeable when the object is affected by several equal disturbances. Taking them into account requires increasing the complexity and reducing the reliability of the ACS. And neglect sharply reduces the accuracy of the system. Therefore, there is a need to develop a method of synthesis of radio technical tracking systems that eliminates the indicated shortcomings.
 Objective. The article presents a synthesis method for high precision radio tracking systems, which are equivalent to combined systems with split control and filtering procedures when the entry useful (preset) action, which is not measured and external disturbances and interferences are present simultaneously.
 Method. Methods of automatic control theory were used to achieve the goal of the research.
 Results. It has been demonstrated that there is a conflict between the conditions for split synthesis of the evaluation (smoothing) filter and the control filter (regulator) in automatic tracking control systems operating with deviation.
 The article offers a solution to the problem of control and evaluation in the framework of two-circuit systems, which are equivalent to combined systems. The second circuit can be presented as a product of a reverse transfer function with an error in the first circuit to the transfer function of Controller, which has a positive feedback from the operator, as well as the reverse transfer function of the control object without integrating links. It is proposed to use for evaluation an evaluation filter with closed filter transfer function instead of an open regulator.
 The characteristic polynomial of a two-circuit automatic control system (ACS) excludes the influence of the stable second-circuit evaluation filter on the stability of the entire ACS. The polynomial of the numerator of the transfer function must have the difference of polynomials by error, which ensures the achievement of invariance.
 A double-circuit ACS is equivalent to a combined one, since it provides the following: invariance of the error with respect to the preset action without directly measuring it; stability of the first circuit with a stable second circuit.
 The synthesized double-circuit ACS is equivalent to a combined one. The author has calculated and constructed the evaluation filter, the influence of this filter on ACS astatism (i. e., on its accuracy) has been analyzed.
 Conclusions. The scientific novelty of the developed method of synthesis of high-precision automatic tracking systems with separate control and filtering procedures in conditions where the controlled value is not measured in the presence of disturbances is as follows. Equivalence to combined systems, in contrast to the methods of differential connections, is achieved not by three, but by two control loops. The practical significance lies in the fact that the proposed method is advisable to use for the construction of surveillance radio engineering systems, where the input useful effect is not measured in the presence of external influences and disturbances. In aircraft control systems.

Advanced Automatic Control and Fault Detection systems are being developed for Navy Submarines and Surface Ships. Within this context a critical concern is the vehicle automatic control system response to the environment, damage that may significantly degrade the vehicle performance, as well as unexpected sensor, actuator, or control surface failures. Such an occurrence may well lead to an automatic control system response that is either inadequate or inappropriate given the current state of the vehicle. In order to maintain mission effectiveness, changes in the vehicle dynamics, as well as component failures must be rapidly detected and recovery actions must be promptly initiated within the automatic control loop. The overall system consists of combining three state-of-the-art techniques—Robust/Reconfigurable Control, Recursive Neural Networks (RNNs), and Fault Detection and Isolation (FDI) algorithms—into a real-time system that provides vehicle monitoring, fault detection, and automatic control of the vehicle from within the executive control loop. The combination of these technologies provides an innovative approach for the identification of both discrete and continuous failures, for differentiating between component failure and environmental influences, and for incorporating model-based fault protection into the autonomous control loop. The current paper describes the use of the RNNs as Virtual Sensors (VS) to provide real-time analytic redundancy of the sensor readings provided to the automatic control system. Since sensor failures will feed directly into the automatic control system, it is critical to check and verify the sensor readings prior to utilization in the automatic control loop since all subsequent commands are predicated on the assumption that the sensed information is correct. As such, a virtual sensor system has been developed which provides complete analytic redundancy of the sensor measurements utilized by the automatic control system. Each sensor reading is checked against real-time simulation predictions of the “true” sensor values and a decision is made as to the validity of the measurement. The sensed values are then either passed on as correct or flagged as being in error and a Virtual Sensor estimate of the “true” sensor reading values are provided to the automatic control system. The results show that the typical sensor failure modes, sensor drift, sensor lock-up, sensor drop-out, sensor data spikes, and sensor noise can be detected and corrected analytically using this approach with zero false positives. A key requirement in developing this system was the capability to avoid reporting false positives, sensor problems, when none actually existed. These real-time systems for Advanced Control and Monitoring can mean the difference between safe, continued operation and potentially catastrophic failures.

To date research on NOX and CO emission reduction in stoker‐fired boilers has been devoted to combustion modification to the overfire air, diverting air to a selected set of burners, using modified low‐NOX burners, using flue gas recirculation or flue gas treatment with specially controlled catalyst and additives. This study introduces a concept that focuses on the dynamics of the boiler and the automatic control system. The objective of this study was to reduce the NO and CO emissions by restructuring the automatic control system and then tuning the control system with parameters that have been optimized with emission reduction as the objective. Dynamic data were obtained from a step‐input test of either the underfire air or the overfire air. These data were used to model the boiler with a transfer function describing the emissions. The analyzer dynamic response was included in the overall model. The control parameters were determined from this overall emissions transfer function by mathematical optimization. These control parameters constituted the initial values in the automatic control system used for the final tests in the boiler. Additional adjustments to reduce the emissions were carried out during boiler operation. A low controller gain and a fast reset time were found to be the most suitable setting for the control system. The NO emissions controlled by the overfire air and CO emissions controlled by the underfire air produced the best results. Through this process, emission reduction in boiler No. 7 of the steam plant at Vanderbilt University of NO from 0.349 to 0.292 lb/106 BTU and CO emission from 0.135 to 0.0821 lb/106 BTU was obtained from the optimization of the control parameters of the automatic control system. © 2006 American Institute of Chemical Engineers Environ Prog, 2006

The aim of the study is to improve the accuracy of the motion control system of ground-based roboticsystems for military purposes (RTK VN) of tracked type based on the application of the method ofconstructing two-circuit automatic control systems equivalent to combined systems. The use of automaticcontrol systems equivalent to combined systems makes it possible to increase the accuracy of automaticcontrol systems by reducing the value of the dynamic error, that is, achieving error invariance,without violating the stability of the system. The objective of the study is the possibility of achieving zeroerror in single-circuit and double-circuit automatic motion control systems RTK. To solve this problem,it is necessary to determine the structure of the ACS and draw up block diagrams of automatic trafficcontrol systems of the RTK VN along the angle of the course. This task can be solved in stages. Duringthe first stage, the connection of control errors in single-circuit automatic control systems with a constantinput effect is considered. The next stage is the justification of the construction of two-circuit systemstaking into account the linear input effect. Next, it is necessary to determine the parameters of thesecond circuit of the two-circuit ACS by the movement of the RTK. The problem considers the relationshipof the dynamic control error in dual-circuit ACS by the movement of the RTK along the angle of thecourse with the linear input effect. The method used in the article allows us to solve the problem ofachieving the invariance of the error in the ACS by the movement of the RTK VN along the angle of thecourse. The paper presents a methodology for determining the parameters and structure of the ACS inorder to achieve zero error, which, in turn, leads to increased accuracy while meeting the requirementsfor the stability of the system. The calculation results confirm the operability of the proposed methodologyand show that with various input effects (constant and linear) in single-circuit and double-circuitACS, the RTK movement along the course can achieve independence of reducing the dynamic errorfrom the stability of the ACS (i.e., achieving error invariance without loss of stability of the system).

Environmental pollution and energy shortage are becoming more and more serious in China. In order to effectively solve these problems, reducing the consumption of non-renewable energy such as coal and increasing new energy such as wind energy has become the main direction of modern power development. However, the new energy represented by wind energy has volatility and randomness. A large number of new energy generation grid connected will inevitably lead to grid frequency fluctuations. So it is necessary to design an automatic generation control system with wind power. This paper focuses on the optimization and innovation of automatic generation control system with wind power, and designs a set of automatic control system with wind power combined with the optimization algorithm data model, so that the wind power can keep the safe and stable operation of the power system after grid connection.

Aiming at causing frequency traffic accidents by the drunken driving, the paper puts forward an automatic locked control system of vehicle drunken driving as a smart solution to prevent the phenomenon. And designs a automatic locked control system based on PIC16F877A. The system hardware modules and software system are elaborated in detailed. At last through the experiment, it verifies that the automatic control system has reached requirement.

The article presents the analysis of the automatic alternate current motor control system, carried out by the author. The automatic control system has been implemented on the existing laboratory stand, containing: the squirrel-cage asynchronous motor and the frequency inverter. The existing stand imposed one of the available speed control methods for the motor and the necessity of the appropriate elements selection for the automatic control system [1]. The automatic control system has been designed and created as the constant value follow-up digital controller. To designate the parameters of the control object the unit step method of was used. After registering the output changes caused by the unit step, the characteristic curve was received that allowed to determine the alternative transmittance of the control object which, in turn, has made possible to find the appropriate controller settings.

A microscope image of the power detector with on-

It is proposed to take into account the influence of uncontrolled disturbances on the regulation of irrigation flow into the stabilization column of the catalytic reforming unit catalyst stabilization unit by changing the coefficients of the polynomial of the denominator of the transfer function of the automatic irrigation flow control system based on a probabilistic approach to robust stability. To study the robust stability of the automatic irrigation flow control system in the stabilization column, a typical scheme of the regulation system is considered. To describe the problem, a general view of the denominator polynomial of the transfer function of an automatic irrigation flow control system in a stabilization column is obtained. For the robust stability of the automatic irrigation flow control system in the stabilization column under the influence of disturbances, the task of estimating the probability of stability of the family of polynomials of the denominator of the transfer function of the automatic control system is set. A family of polynomials of the denominator of the transfer function of an automatic irrigation flow control system in a stabilization column with uncertainty parameters varying in a cube is considered. The problem of estimating the probability of stability of a family of polynomials of the denominator of the transfer function of an automatic irrigation flow control system in a stabilization column is reduced to solving problems: sample generation and probability estimation by frequency. To assess the probability of stability of the family of polynomials of the denominator of the transfer function of the automatic irrigation flow control system in the stabilization column, four polynomials, including the nominal one, are given. Based on generating a sample of one hundred independent random variables, calculating the corresponding polynomials and checking their stability, the considered family of polynomials of the denominator of the transfer function of the automatic irrigation flow control system in the stabilization column has stability with a probability close to unity.

The studies were performed to improve workflow of hydraulic automatic control systems of the tillage units. Tillage quality should not deteriorate. Working bodies of tillage machines have to be moved automatically. Automated devices can be separated into two groups: direct and indirect action. It is preferable to indirect action. The article presents analysis of automatic devices used into tillage machines. Automatic control systems can be hydraulic, electro-hydraulic and pneumatic. Mechanical systems are not effective. Hydraulic systems are cheaper electric and pneumatic. They provide best of energy and quality indicators of technological process of tillage. Automatic control systems are uses draft forces, hitch position, depth of the implement, speed, acceleration and other sensors. Method of computer modeling and optimization of hydraulic automatic control systems of tillage units was developed. Results of computer modeling of hydraulic automatic control systems help to select direction of improving quality and energy indicators of technological process of tillage. Optimized combine implement depth and draft control system of arable unit allow reducing deviation the draft force of the plow; deviation of the depth of plowing is equal to or smaller than agro-technical requirements. Deviation of the draft force was decreased to 13.5 % for deviation specific soil resistance - 20 %, depth of plowing - 0.21 m, deviation of the depth of plowing - 0.019 m (9 %). Deviation of the depth of plowing may be decreased to 0.010 m (4,8 %), but deviation of the draft force shell be increased up to 16.2%. Optimized hydraulic automatic control system of garden tiller with a trapezoidal mechanism leaves smaller untreated soil area from 1.37-1.46 times.

PurposeThe main purpose of this work was elaboration and verification of a method of assessing the sensitivity of automatic control laws to parametric uncertainty of an airplane’s mathematical model. The linear quadratic regulator (LQR) methodology was used as an example design procedure for the automatic control of an emergency manoeuvre. Such a manoeuvre is assumed to be pre-designed for the selected airplane.Design/methodology/approachThe presented method of investigating the control systems’ sensitivity comprises two main phases. The first one consists in computation of the largest variations of gain factors, defined as differences between their nominal values (defined for the assumed model) and the values obtained for the assumed range of parametric uncertainty. The second phase focuses on investigating the impact of the variations of these factors on the behaviour of automatic control in the manoeuvre considered.FindingsThe results obtained allow for a robustness assessment of automatic control based on an LQR design. Similar procedures can be used to assess in automatic control arrived at through varying design methods (including methods other than LQR) used to control various manoeuvres in a wide range of flight conditions.Practical implicationsIt is expected that the presented methodology will contribute to improvement of automatic flight control quality. Moreover, such methods should reduce the costs of the mathematical nonlinear model of an airplane through determining the necessary accuracy of the model identification process, needed for assuring the assumed control quality.Originality/valueThe presented method allows for the investigation of the impact of the parametric uncertainty of the airplane’s model on the variations of the gain-factors of an automatic flight control system. This also allows for the observation of the effects of such variations on the course of the selected manoeuvre or phase of flight. This might be a useful tool for the design of crucial elements of an automatic flight control system.