Controller Output Signal Research Articles

Biological Breakdown of Sports in Athletics Based on Multimedia Image Acquisition Techniques.

This paper provides an in-depth analysis and study of the decomposition of sports biology of athletics events through multimedia image acquisition techniques. The proposed design uses SOPC hardware-software collaboration technology, which makes full use of the parallelism of hardware as well as the flexibility of software to essentially improve the speed of image processing and greatly improve the efficiency of image processing. The high speed and parallelism of hardware are used to realize the image acquisition part with high timing requirements and the preprocessing algorithm with a large number of operations and strong repetition, in addition to the difficulties of many initialization configuration parameters of each peripheral. Additionally, the need for frequent adjustment of peripheral working parameters is solved by making full use of the scalability and flexibility of software, and the control signals output by software can coordinate the work of each hardware module to ensure that each module of the system cooperates. It is also possible to coordinate the work of each hardware module through the control signal output from the software to ensure that each module of the system cooperates and operates in an orderly and efficient manner and provides the possibility of realizing a higher level of the image processing algorithm. The system includes four main factors: swinging action, supporting action, vacating action, and speed rhythm. Based on this system, 14 key kinematic indicators were selected to reflect the technical status of the youth walkers. The landing angle decreased with the increase of speed, and the landing technique was insufficient; it had better control of the large and small arm angle, and their stride width was open, while the other four athletes showed increased tension in the hip joint and upper limb with the increase of walking speed, as well as the wrong action of forward and internal rotation of the large and small arms.

Stability of microgrid cluster with Diverse Energy Sources: A multi-objective solution using NSGA-II based controller

The stability of microgrids with increased penetration of renewables is a major concern. This is mainly due to their intermittent nature varying from time to time. While designing the stabilisers, the amplitude of the control signals is not given due consideration. This work develops frequency controller systems for a microgrid cluster composed of several energy sources. In addition to the frequency deviation in microgrids, the aspect of controller output signals has also been considered. A dynamic model of four microgrids linked with tie-lines is developed. The frequency stability is ensured utilising a fractional order controller using the Non-dominated Sorting Genetic Algorithm - II (NSGA-II). The multi-objective problem is formulated with opposing objectives as frequency deviation and the controller output signal for determining the controller. The performance is compared with Tilt Integral Derivative (TID), TID with filter (TIDF), Proportional Integral Derivative (PID) and PID with filter (PIDF) controllers. Besides, the superiority of the algorithm is analysed by comparing the results with those from other algorithms in the literature. The effectiveness is analysed under numerous scenarios of load and renewable uncertainties. Further, the sensitivity investigation has also been performed by varying the internal parameters within the range of ±40%.

Laser beam jitter control of the link in free space optical communication systems

The pointing and tracking performance of laser beams in free space optical communication (FSOC) systems and other precision laser systems is severely limited by beam jitter. This research proposes an adaptive control method to suppress beam jitter by adjusting the deflection angle of the beam by controlling the fast steering mirror (FSM) driven by piezoelectric ceramics. In order to verify the effectiveness of the control method, we have established an experimental platform. First, the internal controller of the FSM is adjusted to an approximately linear system, aiming to turn the input and output control signals into a linear relationship. Based on the adaptive filter, a filtered-x variable step-size normalized least mean square (FxVSNLMS) algorithm is proposed. To further improve the robustness of the controller, a Proportion Integral Differential (PID) controller and an adaptive controller which work in parallel are then added to the control loop. Finally, experimental results are provided and compare with the traditional controller and other adaptive control methods. Experimental results show that for more complex narrow-band and broad-band mixed beam disturbances, the control scheme developed in this research is significantly improved. This conclusion has also been verified on the ground experimental platform of FSOC.

Fault Detection System for 500 kV AC Fault Current Limiter Based on High-Coupled Split Reactor

Aiming at the problem of limiting high short-circuit current in 500 kV AC power grid, we develop an economical-type fault current limiter (FCL) based on high-coupled split reactor (HCSR), namely, HCSR-FCL. This paper addresses designing the early fault detection system of HCSR-FCL. Firstly, it introduces the working principles of HCSR-FCL and gives the system design of HCSR-FCL control system. Subsequently, it discusses the real-time requirement of the HCSR-FCL control system, and apply an early short-circuit fault detection algorithm based on the ratio of the summation of squared three-phase currents (SSC). Then, it gives implementation of the applied algorithm, and also designs the hardware of fault detection unit. Finally, simulation verification on RTDS (real-time digital simulation system) platform is given. Experimental results show that the designed system can detect short-circuit fault rapidly and robustly. When short-circuit occurs, the control system designed can output control signals, which enables the FCL into operation quickly.

Unknown Input Observers for Discretized Systems With Application to Networked Systems Corrupted by Sparse Malicious Packet Drops

Digital estimators for networked systems are proposed where the plant output measurements and control signals are corrupted by independent sparse malicious packet drop errors. The estimators comprise output sparse error approximators and unknown input observers (UIOs). The advantage of using digital estimators is that in many cases the condition for the existence of an UIO fails for continuous-time (CT) plants while it holds for discretized plants. A class of CT systems for which the existence condition for the UIO holds in the discrete-time (DT) domain is characterized. The proposed digital estimators are tested on a nonlinear networked control system (NCS). As part of our analysis, we study the existence of unknown input observers for discretized systems and show that discretization does not negatively impact the existence of UIOs and in some cases can facilitate the construction of UIOs when they do not exist for the CT systems.

PERFORMANCE STUDIES ON WATER FLOW CONTROL USING P, PI AND PID CONTROLLERS

The main purpose of this study is to revitalize the concept of wise and controlled supply of water for domestic, industrial and agricultural applications which facilitate sustainable usage of fresh water resources. As Eritrea is striving to manage its water resources, attention paid primarily to enable water flow control mechanisms in municipal water distribution systems. A table top process control trainer (PCT) was tested through proportional(P), integral (I) and derivative (D) control mechanisms using Ziegler-Nichols second method to evaluate the tuning variables. Applying exclusively P control action, critical period of oscillation (𝑃𝑃𝑐𝑐𝑐𝑐) was estimated as 1.4 sec at proportional band value of 9. P, PI and PID controller performance studies were conducted with tuned variables on the water flow control system at different step disturbances between 20 – 50 % and their corresponding responses were characterized. P controller exhibited faster responses with consistent increments in offset, PI controller recorded highest overshoot values with negligible offset and prolonged settling times. PID controller showed less overshoot values and faster response times than PI but it increased chatter on the control output signal. The study revealed that the system can be safely controlled between 0-80 LPH. If the offset is not a major concern, P controller would be reflected suitable with simple design and minimum expenditure, else PI controller makes offset to zero though it possesses higher settling times. In other words, PID controller is complex using more tuning parameters, need expensive maintenance, and has resulted an intermittent noise in the output signal.

On the fuzzy logic controller development for a hybrid hydrogen vehicle

Introduction (problem statement and relevance).The ability to combine the advantages of hydrogen fuel cells and lithium batteries in a hybrid electric vehicle is a fundamental challenge in the development of highly efficient, environmentally friendly transportation. At the same time, the coordinated operation of onboard sources requires the creation of complex control algorithms for all involved power supply and power consumption systems.The purposeof the research was to study the practical applicability of fuzzy logic algorithms when creating a fuel cells battery controller.Methodology and research methods.The study used modern mathematical methods for processing the controller input signals of a hydrogen vehicle hybrid power unit and generating output control signals to provide the most optimal control modes for a fuel cells battery.Scientific novelty and results.The proposed approach, based on the use of fuzzy logic algorithms, has made it possible to control the fuel cell battery power ensuring its efficient operation as part of a vehicle hybrid electric drive. The analysis of the obtained results indicated the effectiveness of the method.Practical significance.The proposed algorithms make it possible to develop and implement advanced hydrogen power systems controllers for a vehicle.

Performance Analysis of Fuzzy Logic Controller Applied on Portable Roaster

Roaster is a device commonly used to roast various products, especially for food processing. In the roasting process, temperature parameter plays a major role in determining the final quality of the roasted product. In real-world applications, some products must be roasted at low temperatures such as cocoa products and others must be roasted at high temperatures such as coffee products. In addition, roasting is sometimes not always carried out at a constant temperature, but sometimes it must be done at various roasting temperature levels for the purpose of forming the optimal flavour. Thus, a roaster must be able to operate at the desired operating temperature, not only a constant operating temperature but also able to work with varying operating temperatures. For this purpose, a roaster must be equipped with a reliable temperature controller. Several control models have been developed by many researchers, including fuzzy logic control. This research was conducted to design, implement, and evaluate the performance of a control system based on fuzzy logic on a laboratory scale portable roaster. For this study, a fuzzy control system with two input variables, namely the difference in temperature and changes in temperature difference as well as one control signal output variable, had been designed to regulate the roasting temperature on the roaster. To evaluate its performance, the domain membership function of the input and output variables was varied. The design was then applied to the microcontroller-based control system hardware attached to the portable roaster. The test results show that the fuzzy logic control was able to regulate the roast temperature stably. With a varied roast temperature setpoint, the control system can follow and maintain the target with small temperature variation.

Identification of signals as one of the stages of synthesis of the system of automatic stabilization of the height of the fluidized bed in the grain dryer

Drying is one of the most responsible and energy-intensive post-harvest grain pro-cessing operations. The constant rise in heat prices has led to the search for new designs of grain dryers, or improvements to existing ones. Studies of well-known scientists such as Romankov, Rezchikov, Rashkovskaya have proven the potential effectiveness of using a fluid-ized bed for drying grain.The degree to which this drying efficiency approaches the potential is determined by how much the change in the actual humidity of the material during drying approaches the theoretical drying curve at the same resource consumption and the same initial state of the material to be dried.The study of the designs of fluidized bed grain dryers showed that they show irregular fluctuations in the height of the fluidized bed, and, accordingly, the efficiency of energy use for drying. The reason for this phenomenon is related, on the one hand, to random fluctua-tions in the amount of grain in the fluidized bed, and on the other - to the shortcomings of the system of automatic stabilization of its height.Taking into account the provisions of the theory of optimal control indicates that max-imizing the accuracy of stabilization of a given value of the height of the fluidized bed should be achieved by developing an optimal multidimensional stabilization system of the specified height. The basis for solving the first of these is the study of the design of a fluidized bed grain dryer.The decomposition of the grain dryer allows to present it in the form of a set of multidimensional objects with pure delay. The size of this set is determined by the number of cascades, and the dynamic characteristics of its elements depend on the distance of the cascade to the gate.The degree of connections between input-output signals in the form of correlation and cross-correlation functions was studied, and the physical processes occurring in the grain dryer were analyzed. As a result of applying the Blackman-Tukey algorithm to the implemen-tations of the components of the control signal vectors and output signals, estimates of the corresponding correlation functions and spectral densities for all elements of the set of con-trol objects were obtained. The discrete Fourier transform of smoothed estimates of correla-tion and cross-correlation functions allowed us to calculate estimates of the spectral and mutual spectral densities of the respective signals. Approximation of spectral and mutual spectral density estimates by the method of generalized logarithmic frequency characteristics allowed to determine the mathematical description of these signals in the form of spectral density expressions, which will be the basis for the next stage of object identification.

Observer-Based Fixed-Time Adaptive Fuzzy Bipartite Containment Control for Multiagent Systems With Unknown Hysteresis

This article studies the fixed-time fuzzy adaptive bipartite containment quantized control problem for nonlinear multiagent systems subject to unknown external disturbances and unknown Bouc–Wen hysteresis. The output and input control signals of the systems are quantized by sector-bounded quantizer. A disturbance observer and a fuzzy state observer are simultaneously designed to estimate unknown external disturbances and unmeasured states, respectively. Then, to solve the difficulty caused by Bouc–Wen hysteresis, a distributed control strategy is presented by using the disturbance observer. In addition, the bipartite containment control performance of multiagent systems can be realized, and the stability of the closed-loop multiagent systems can be proved to be the semi-global practical fixed-time stability by Lyapunov theory and fixed-time theory. Finally, a practical simulation example is shown to demonstrate the effectiveness of the proposed scheme.

Intelligent Control System for Corn Harvester

Based on the traditional corn harvester, this paper optimizes the basic structure of the harvester, analyzes the transmission mode and working principle of each mechanism, and designs and selects the electric devices and sensors needed in the optimization process. Combined with PLC control theory and output signal processing of sensors, the hydraulic components of walking hydraulic system of electric devices and harvesters are controlled.

A Novel Copper Layer-Based Field-to-Trace Coupling Model and EMS Evaluation Method for DSP-Based Control Circuit in MMC-HVDC System

Underlying control circuit failure problems, especially control signal output failure problems, widely occur in high-voltage large-current modular multilevel converter (MMC) valve towers. The failure mechanism for the digital signal processor (DSP)-based control circuit is studied in this article. This study is based on the combination of low-voltage-level integrated circuit (IC) immunity model and a new perspective on the field-to-trace coupling effect. A novel copper-layer-based field-to-trace coupling model which combines the power system and digital control circuit in the MMC valve tower is proposed. Therefore, the specific electromagnetic interference (EMI) value conducted into the IC can be calculated. Then a new DSP IC electromagnetic sensitivity (EMS) evaluation method is proposed, which can be a guideline in industrial applications. To show the validity and accuracy of the field-to-trace coupling model, an indirect laboratory experiment is designed, then a situation is considered in this article, and the results are compared with PSpice circuit simulations, which show acceptable relative errors. Moreover, based on the situation considered above, one application example of the novel evaluation method is described in detail.

Динамика непрерывных систем управления с элементами запаздывания в составе корректирующих фильтров

Matters concerned with the application of correction devices containing delay elements are addressed. Such filters are proposed as an alternative to the high-pass filters and low-pass first-order filters that are widely used in control systems. It is shown that by using filters containing delay elements, the power of high-frequency interference in the controller output signal can be reduced by up to 30% in comparison with the conventional filters. It should be noted that these results are obtained in using the proposed filters in closed-loop continuous systems. Two filter configuration versions used in control applications were analyzed. In the first version, the filters are connected in series in the control loop (as applied to astatic systems with a proportional-differentiating controller in both linear and relay modes of operation). In the second version, a correction filter connected in the local feedback is used (taking a generalized representation of the instrument-assisted position tracking system as an example). The article proposes a fairly simple method for determining the parameters of filters with a delay element that make it possible to use conventional techniques for synthesizing controllers in the frequency domain and estimating their dynamic properties.

Exploiting codon usage identifies intensity-specific modifiers of Ras/MAPK signaling in vivo.

Signal transduction pathways are intricately fine-tuned to accomplish diverse biological processes. An example is the conserved Ras/mitogen-activated-protein-kinase (MAPK) pathway, which exhibits context-dependent signaling output dynamics and regulation. Here, by altering codon usage as a novel platform to control signaling output, we screened the Drosophila genome for modifiers specific to either weak or strong Ras-driven eye phenotypes. Our screen enriched for regions of the genome not previously connected with Ras phenotypic modification. We mapped the underlying gene from one modifier to the ribosomal gene RpS21. In multiple contexts, we show that RpS21 preferentially influences weak Ras/MAPK signaling outputs. These data show that codon usage manipulation can identify new, output-specific signaling regulators, and identify RpS21 as an in vivo Ras/MAPK phenotypic regulator.

MODELING PREDICTIVE TRACKING CONTROL FOR MAX-PLUS LINEAR SYSTEMS IN MANUFACTURING

Discrete event systems, also known as DES, are class of system that can be applied to systems having an event that occurred instantaneously and may change the state. It can also be said that a discrete event system occurs under certain conditions for a certain period because of the network that describes the process flow or sequence of events. Discrete event systems belong to class of nonlinear systems in classical algebra. Based on this situation, it is necessary to do some treatments, one of which is linearization process. In the other hand, a Max-Plus Linear system is known as a system that produces linear models. This system is a development of a discrete event system that contains synchronization when it is modeled in Max-Plus Algebra. This paper discusses the production system model in manufacturing industries where the model pays the attention into the process flow or sequence of events at each time step. In particular, Model Predictive Control (MPC) is a popular control design method used in many fields including manufacturing systems. MPC for Max-Plus-Linear Systems is used here as the approach that can be used to model the optimal input and output sequences of discrete event systems. The main advantage of MPC is its ability to provide certain constraints on the input and output control signals. While deciding the optimal control value, a cost criterion is minimized by determining the optimal time in the production system that modeled as a Max-Plus Linear (MPL) system. A numerical experiment is performed in the end of this paper for tracking control purposes of a production system. The results were good that is the controlled system showed a good performance.

Design of temperature humidity and illumination control system for indoor flowers

In order to improve the automation of indoor flower environment monitoring, enable the flowers grow in the best environment, this paper designs an automatic control system of temperature, humidity and illumination based on STC89C52 single chip microcomputer. Temperature sensor DS18B20 is applied to sense indoor air temperature, meantime, YL-69 soil moisture sensor and photosensitive resistance are used to sense soil relative humidity and light intensity respectively. Temperature, humidity and light intensity are transmitted to single chip microcomputer for analysis and processing, and the results are displayed by OLED display module. The upper and lower limits of environmental parameters are manually preset through the keyboard. When the temperature and light intensity exceed the upper limit, the system can send out alarm signals and output control signals to drive the corresponding actuator to work; when the soil moisture is lower than the lower limit, the system will automatically alarm and water automatically; when the humidity reaches the upper limit, watering will be stopped to ensure the indoor environmental parameters in the best value suitable for flower growth. The system has been tested and debugged. The results show that the control system can effectively process and display the flower environment information, achieving the purpose of automatically adjusting and controlling the temperature, humidity and illumination of flowers, has strong promotion value.

Principles, fundamentals, and applications of programmable integrated photonics

Programmable integrated photonics is an emerging new paradigm that aims at designing common integrated optical hardware resource configurations, capable of implementing an unconstrained variety of functionalities by suitable programming, following a parallel but not identical path to that of integrated electronics in the past two decades of the last century. Programmable integrated photonics is raising considerable interest, as it is driven by the surge of a considerable number of new applications in the fields of telecommunications, quantum information processing, sensing, and neurophotonics, calling for flexible, reconfigurable, low-cost, compact, and low-power-consuming devices that can cooperate with integrated electronic devices to overcome the limitation expected by the demise of Moore’s Law. Integrated photonic devices exploiting full programmability are expected to scale from application-specific photonic chips (featuring a relatively low number of functionalities) up to very complex application-agnostic complex subsystems much in the same way as field programmable gate arrays and microprocessors operate in electronics. Two main differences need to be considered. First, as opposed to integrated electronics, programmable integrated photonics will carry analog operations over the signals to be processed. Second, the scale of integration density will be several orders of magnitude smaller due to the physical limitations imposed by the wavelength ratio of electrons and light wave photons. The success of programmable integrated photonics will depend on leveraging the properties of integrated photonic devices and, in particular, on research into suitable interconnection hardware architectures that can offer a very high spatial regularity as well as the possibility of independently setting (with a very low power consumption) the interconnection state of each connecting element. Integrated multiport interferometers and waveguide meshes provide regular and periodic geometries, formed by replicating unit elements and cells, respectively. In the case of waveguide meshes, the cells can take the form of a square, hexagon, or triangle, among other configurations. Each side of the cell is formed by two integrated waveguides connected by means of a Mach–Zehnder interferometer or a tunable directional coupler that can be operated by means of an output control signal as a crossbar switch or as a variable coupler with independent power division ratio and phase shift. In this paper, we provide the basic foundations and principles behind the construction of these complex programmable circuits. We also review some practical aspects that limit the programming and scalability of programmable integrated photonics and provide an overview of some of the most salient applications demonstrated so far.

Researching the efficiency of buck converter synchronous rectifier

The object of study is synchronous buck-voltage converter with digital control system. One of the most problematic things is energy changing and transmission in converters to reach certain numerical range with minimal losses in the components of the electrical circuit. An enormous calculated parameters of electrical scheme. There was advised and described both structure and electrical scheme of synchronous converter, which, thanks to digital system, provides dates with more accuracy connected with an impact on working scheme. There was shown detailed analysis example with a numerical value for the certain elements of electrical scheme. It’s a fundament in order to choose certain parts of electrical scheme according to the certain categories.During research there was used selection of hardware and software tools: elements for buck-converter – key, diode and capacitor; certain voltage and frequency range for microcontroller; control of the power keys of the circuit with the corresponding operating parameters for driver. There was analyzed and calculated all over the possible losses during the process bucking of the voltage to the certain level, an enormous losses in the components of the converter electrical scheme – induction coil, keys and capacitors. It’s an important part of synchronous buck-converter. There was calculated power losses and efficiency through the received graphics of keys commutation in electrical scheme. There were received graphic dependence of converter efficiency on output power; time characteristics of the control signal pulse-width modulation (PWM) and output voltage; dependence on the commutation losses. This is because advised synchronous converter has a set of features. Particularly analog to digital converter in the capacity of feedback, digital regulation system with a discrete step and rectification by replacing diodes with actively controlled switches. There are keys of low-side and high-side levels according to the passing voltage and current values. Therewith provides possibility for receiving more accuracy value. In comparison with analogic buck-converters, this converter has voltage parameter with fractional error.

On the Resiliency of Power and Gas Integration Resources Against Cyber Attacks

Integration of power and gas systems has been recently proposed as a portfolio solution to deal with the sporadic availability of renewables and enhance the flexibility of power systems. In an integrated system, where critical operating information and control signals of both systems need to be communicated, the risk of cyber attack is intensified. In this article, we present a new model for the integration of power and gas systems using power-to-gas (PtG) and gas-fired generation (GfG) facilities. We demonstrate how the operation of the integrated system can be adversely impacted during cyber attacks that may not be detected using traditional methods. We propose two new detection schemes for false data injection attacks against the input and output signals of the PtG/GfG facility scheduler. In the first scheme, a supervised machine-learning technique, based on the convolutional neural network and wavelet transforms, is adopted to detect attacks on the information received by the facility scheduler. In the second scheme, a hybrid neural network is developed, based on an unsupervised learning technique, that requires no labeled training information to detect attacks on the output control signals issued by the scheduler. In both schemes, information acquired from local sensors and deterministic estimation methods is utilized for signal evaluation. The proposed schemes are incorporated into the facilities' scheduler to create a cyber-attack resilient scheduling model in an integrated power and gas grid. The efficacy and feasibility of the proposed model are evaluated via numerical studies using the IEEE30-bus power system integrated with the Belgian gas grid as the test bed using historical operating parameters.

A modified active disturbance rejection control for a wastewater treatment process

Abstract Waste water treatment process (WWTP) control has been attracting more and more attention. However, various undesired factors, such as disturbance, uncertainties, and strong nonlinear couplings, propose big challenges to the control of a WWTP. In order to improve the control performance of the closed-loop system and guarantee the discharge requirements of the effluent quality, rather than take the model dependent control approaches, an active disturbance rejection control (ADRC) is utilized. Based on the control signal and system output, a phase optimized ADRC (POADRC) is designed to control the dissolved oxygen and nitrate concentration in a WWTP. The phase advantage of the phase optimized extended state observer (POESO), convergence of the POESO, and stability of the closed-loop system are analyzed from the theoretical point of view. Finally, a commonly accepted benchmark simulation model no. 1. (BSM1) is utilized to test the POESO and POADRC. Linear active disturbance rejection control (LADRC) and the suggested proportion-integration (PI) control are taken to make a comparative research. Both system responses and performance index values confirm the advantage of the POADRC over the LADRC and the suggested PI control. Numerical results show that, as a result of the leading phase of the total disturbance estimation, the POESO based POADRC is an effective and promising way to control the dissolved oxygen and nitrate concentration so as to ensure the effluent quality of a WWTP.