Pressure Control System Research Articles

Steam Pressure Control of Marine Boiler Based on AFSA-PSO-LSSVM

Abstract To solve the problem that the main steam pressure fluctuates greatly when the load of the combustion control system of the marine main boiler changes suddenly, present a combined inverse control system of Support vector machine and PID to control the steam pressure intelligently. The inverse model of the nonlinear system identified by LSSVM is used as the feedforward controller and the PID controller is used as the feedback controller. The hybrid intelligent algorithm of artificial fish swarm Algorithm and particle swarm optimization is used to optimize the parameters of the control system. The AFSA algorithm is used to search the initial values of the parameters and the PSO algorithm is locally updated. Finally, the mechanism of the steam pressure control system of the marine boiler is modeled and simulated, and the algorithm models of AFSA-PSO-LSSVM-PID, AFSA-LSSVM-PID, PSO-LSSVM-PID and LSSVM-PID are established. The experimental results show that the AFSA-PSO-LSSVM-PID model has a good dynamic, stability, anti-interference ability and robustness.

Performance analysis of IMC-PID controller on PCT-14 air pressure control system

This research presents a comprehensive performance analysis of the IMC-PID controller implemented in the PCT-14 air pressure control system, a platform ideal for experimenting with various control methodologies. The study aims to compare the effectiveness of the IMC-PID controller with IMC-PIDF, Good Gain - PID and Skogestad's - PI controllers, focusing on response time characteristics based on the simulation of the PCT-14′s transfer function. Performance analysis is conducted by comparing system response characteristics to set point changes, including rise time, overshoot, settling time, peak time, and steady-state error. To validate the controller's effectiveness, performance index value such as Integrated Absolute Error (IAE) was calculated. The research findings indicate that the IMC-based PID controller outperforms the Good Gain – PID, Skogestad-PI, and IMC-PIDF controllers in handling set point changes.•Simulating the transfer function of the PCT-14 air pressure control system to examine the response time characteristics of the IMC-PID, IMC-PIDF, Good Gain - PID, and Skogestad's - PI controllers.•Conducting a performance analysis by comparing system response characteristics in response to changes in set point values.•Calculating performance index value, IAE to assess the controllers' effectiveness.

Comparison study of two control strategies for the small pressurized water reactor

The control strategy has a significant impact on the control performance of the reactor system. This paper investigates the feedwater flow and steam flow control strategies for small pressurized water reactors. First, the mathematical model of the SPWR Nuclear Steam Supply System is introduced. Second, a dual-constant control strategy was proposed, and the feedwater flow rate and steam pressure control systems under the two control modes were designed. Moreover, a steam bypass control system was designed to avoid excessive steam pressure under the feedwater flow control mode, and the reactor power and pressurize control systems were introduced. Simulation results indicate that the two control modes both meet the SPWR control requirements. However, the feedwater flow control mode has better reactor coolant temperature and steam pressure control performances during the load rejection transient, owing to the timely discharge of heat from the reactor coolant system through the steam bypass system.

Математичне моделювання руху автобронетанкової техніки з колісною формулою 4×4 при зміні тиску в шинах коліс на прикладі КрАЗ-Спартан

The authors proposed a study of the passability of trucks and armored vehicles of the National Guard of Ukraine with a 4x4 wheel formula. The movement of armored vehicles (AMT) of the National Guard of Ukraine involves movement both on public roads and off-road. The possibility of increasing cross-country ability by ensuring optimal pressure distribution in the tires of the wheels is being considered. The increase in bearing capacity in difficult operating conditions can be estimated with the help of modern mathematical tools. This allows the vehicle equipment of the National Guard of Ukraine to study the cross-country ability and select optimal parameters when performing service and combat tasks with a certain ratio of technical characteristics in different operating conditions. As a result of the full-scale war of the Russian Federation against Ukraine, more serious technical requirements are imposed on the vehicles of the Armed Forces of Ukraine (AFU) and the National Guard of Ukraine (NGU) than in peacetime. Among these requirements, maneuverability is in the first place - controllability is ensured by the ability to move at high speed over rough terrain. The patency of the AMT of the National Guard of Ukraine depends on many factors, the main ones of which are: the type and quality of the surface on which movement takes place, the pressure in the tires of the wheels, the weight of the vehicle, the order of passing the route of the convoy, etc. The central air pressure control system in wheel tires (SRPRS) is widely used in various variants of automotive equipment with high traffic intensity, but the main disadvantage of such systems is the need to minimize tire pressure to improve cross-country ability on load-bearing surfaces with low load-bearing capacity. This tolerance can cause the tire to slip off the rim, overheat or burst. This is due to the fact that the maximum speed is limited due to the risk of system failure. It is recommended to determine the influence of various factors in order to ensure the required level of support patency and analyze it using the example of the KrAZ-SPARTAN armored car with a 4×4 wheel formula.

Ultra-high-precision pneumatic force servo system based on a novel improved particle swarm optimization algorithm integrating Gaussian mutation and fuzzy theory

In this study, an ultra-high-precision pneumatic force servo system (UPFSS) is proposed. On the one hand, a novel air-floating pneumatic cylinder (AFPC) with an air-floating piston capable of independent air supply and exhaust is developed for this system, and its special flow channel design allows the air-floating piston to be suspended in the cylinder without being constrained by the pressure in the chambers. The friction force of the AFPC is less than 0.0049 N. On the other hand, a leakage chamber is constructed to simulate the clearance between the air-floating piston and the cylinder wall, and a fuzzy proportional integral (FPI)-based pressure control system (PCS) is designed for the simulated leakage chamber. Furthermore, a novel particle swarm optimization algorithm integrating Gaussian mutation and fuzzy theory (IGF-PSO) is presented. After testing, the IGF-PSO algorithm is found to have outstanding optimization performance. Then, the parameters of the FPI controller are optimized through the IGFPSO algorithm. Experimental comparisons reveal that the steady-state error achieved by the parameter-optimized pressure controller in response to the leakage condition is about 38 % smaller than that achieved by the pressure controller with parameters obtained using the trial-and-error method. Finally, the UPFSS is tested by using the optimized PCS to supply compressed air to the chamber of the AFPC. The results show that the UPFSS achieves a steady-state error of no more than 0.0279 N in the continuous step response within the range of 240 N.

An Enhanced Vacuum-Assisted Resin Transfer Molding Process and Its Pressure Effect on Resin Infusion Behavior and Composite Material Performance.

In this paper, an enhanced VARTM process is proposed and its pressure effect on resin infusion behavior and composite material performance is studied to reveal the control mechanism of the fiber volume fraction and void content. The molding is vacuumized during the resin injection stage while it is pressurized during the mold filling and curing stages via a VARTM pressure control system designed in this paper. Theoretical calculations and simulation methods are used to reveal the resin's in-plane, transverse, and three-dimensional flow patterns in multi-layer media. For typical thin-walled components, the infiltration behavior of resin in isotropic porous media is studied, elucidating the control mechanisms of fiber volume fraction and void content. The experiments demonstrate that the enhanced VARTM process significantly improves mold filling efficiency and composite's performance. Compared to the regular VARTM process, the panel thickness is reduced by 4% from 1.7 mm, the average tensile strength is increased by 7.3% to 760 MPa, the average flexural strength remains at approximately 720 MPa, porosity is decreased from 1.5% to below 1%, and the fiber volume fraction is increased from 55% to 62%.

Wavy-attention network for real-time cyber-attack detection in a small modular pressurized water reactor digital control system

Global interest in advanced reactors has been reignited by recent investments in small modular reactors and micro-reactor design. The use of digital devices is essential for meeting the size and modularity requirements of small modular reactor controls. By fully digitizing the small modular reactor control systems, critical information can be obtained to optimize control, reduce costs, and extend the reactor’s lifetime. However, the potential for cyber-attacks on digital devices leaves digital control systems vulnerable. To address this risk, this study presents a novel wavy-attention network for sensor attack detection in nuclear plants. The wavy-attention network comprises stacks of batch-normalized, dilated, one-dimensional convolution neural networks, and sequential self-attention modules, superior to conventional single-layer networks on sequence classification tasks. To evaluate the proposed wavy-attention network architecture, the International Atomic Energy Agency’s Asherah Nuclear Simulator and a false data injection toolbox found in the literature, both implemented in MATLAB/SIMULINK, are utilized. This approach leverages changes in process measurements to identify and classify cyber-attacks on priority signals using the proposed wavy-attention network. Three false data injection attacks are simulated on the simulator’s pressure, temperature, and level sensors to obtain representative process measurements. The wavy-attention network is trained and validated with normal and compromised process variables obtained from the simulator. The performance of the wavy-attention network to discriminate between the reactor states using the test set shows 99% accuracy, as opposed to other baseline models such as vanilla convolution neural networks, long short-term memory networks, and bi-directional long short-term memory networks with 90%, 77%, and 91% accuracy, respectively. An ablation study is also conducted to test the contribution of each component of the proposed architecture. The theoretical framework of the proposed wavy-attention network and its implementation for nuclear reactor digital sensor attack detection are discussed in this paper.

Research on the cabin pressure control system based on the gray wolf fuzzy PID algorithm

The cabin pressure control system is typically nonaffine-nonlinear time-varying system. In this paper, the fuzzy PID control method optimized by gray wolf algorithm is proposed to solve the problems of large overshoot and long adjustment times in traditional control methods. Simulation results show that the fuzzy PID control method optimized by gray wolf algorithm proposed in this paper improves the dynamic characteristics of the system, reduces cabin pressure error and adjustment time, stabilizes the control process, and improves the comfortableness of passengers.

СИСТЕМА АВТОМАТИЧЕСКОГО РЕГУЛИРОВАНИЯ ДАВЛЕНИЯ В НЕФТЕГАЗОВОМ СЕПАРАТОРЕ

The features of oil production from flowing wells and methods of utilization of associated petroleum gas are considered. A system for automatic pressure control in an oil and gas separator is proposed using an adjustable electric drive to control the position of the damper that controls the volume of the oil and gas mixture

Development and evaluation of a 2oo3 safety controller in FPGA using fault tree analysis and Markov models

The Safety integrity level (SIL) is a measure of the reliability and availability of a safety instrumented system. SIL determination involves qualitative and quantitative analysis based on international standards such as IEC 61508 and IEC 61511. Several techniques can be used to analyze safety instrumented systems, including reliability block diagrams, fault tree analysis, and Markov models. The aim of this paper is to design and evaluate a pressure control system for a compressed nitrogen tank using a PID controller implemented in a field programmable gate array with 2 out of 3 architecture. This architecture ensures the safety of measurements and command of the system through a voting arrangement. The availability of the system is determined by the redundancy and the one hardware failure tolerance. The quantitative analysis is performed by calculating the probability of failure on demand per hour using Markov models or a relevant probabilistic approach based on fault tree analysis. The Markov model method gives the probability of failure of the system in different states during the system life cycle. The fault tree analysis method determines the probability of failure of the system using its equivalent failure rate. Furthermore, this paper compares the SIL result obtained by each model.

Acellular Perfusate is an Adequate Alternative to Packed Red Blood Cells During Normothermic Human Kidney Perfusion.

Brief normothermic machine perfusion is increasingly used to assess and recondition grafts before transplant. During normothermic machine perfusion, metabolic activity is typically maintained using red blood cell (RBC)-based solutions. However, the utilization of RBCs creates important logistical constraints. This study explored the feasibility of human kidney normothermic perfusion using William's E-based perfusate with no additional oxygen carrier. Sixteen human kidneys declined for transplant were perfused with a perfusion solution containing packed RBCs or William's E medium only for 6 h using a pressure-controlled system. The temperature was set at 37 °C. Renal artery resistance, oxygen extraction, metabolic activity, energy metabolism, and histological features were evaluated. Baseline donor demographics were similar in both groups. Throughout perfusion, kidneys perfused with William's E exhibited improved renal flow (P = 0.041) but similar arterial resistance. Lactic acid levels remained higher in kidneys perfused with RBCs during the first 3 h of perfusion but were similar thereafter (P = 0.95 at 6 h). Throughout perfusion, kidneys from both groups exhibited comparable behavior regarding oxygen consumption (P = 0.41) and reconstitution of ATP tissue concentration (P = 0.55). Similarly, nicotinamide adenine dinucleotide levels were preserved during perfusion. There was no evidence of histological damage caused by either perfusate. In human kidneys, William's E medium provides a logistically convenient, off-the-shelf alternative to packed RBCs for up to 6 h of normothermic machine perfusion.

A REVIEW ON DEVELOPMENT OF COLON TARGETED DRUG DELIVERY SYSTEM

The purpose of this review was to select a promising drug delivery system for colon diseases. This review covers the development of Colon Targeted Drug Delivery System (CTDDS) using 36 y (1986-2022) data from various research and review articles. All fig. designed using by BioRender website. vThe colon-targeted drug delivery systems developed for the specific site drug delivery which applied for both local and systemic actions of the drug; since the drug targeted to be release within the colon, the unwanted systemic side effects are reduced along with it. Systemic side effects include organ damage, respiratory diseases and, cardiovascular damage and other illnesses. Colon-targeted drug delivery system used in the treatment of diseases in the colon, including ulcerative colitis, irritable bowel syndrome and colorectal cancer. The benefit of colon-targeted drug delivery besides the reduction of side effects also include protection from premature drug release or burst in the stomach or small intestine before reaching the colon. For the development of drugs with such benefits and advantages, drug delivery systems and approaches have used for Colon targeted drug delivery systems, varying from conventional colon-targeting drug delivery systems to novel approaches for Colon-targeted drug delivery systems. Conventional drug delivery includes the use of prodrugs, pH-dependent, time-dependent, matrix-based systems, polysaccharides-derived systems, and bio-adhesive system while novel approaches include types such as port system, pulsincap system, pressure-controlled system, osmotic controlled system, CODES, and the newest approach wish is the use of nanotechnology in colon targeted drug delivery. In this research both techniques reviewed, and their types discussed as well. The limitation of their uses and the advantage of each system discussed with a breakdown of the different mechanisms used to formulate such systems. A successful colon targeting delivery can release the drug to a specific segment in colon due to presence of different colonic enzymes formed by microorganisms that metabolize drug carrier linkage. Use of combined approaches i.e., conventional systems and newer approaches may be the best way to cure colon diseases using an optimized colon drug delivery system.

Research on dynamic PI parameter tuning of double-fed wind turbine based on ant colony algorithm

Considering the drawbacks of flexible adjustment of PI controller control parameters in the constant pressure control system of doubly fed fans, a PI controller control parameter flexible adjustment method considering ant colony optimization algorithm (ACO) is proposed. This method uses the proportional coefficient and integration time parameters in the PI controller as the ants in the ant colony optimization algorithm, and the ultimate optimization goal is to control the absolute error integration function. During the control process, the parameters of the PI controller are dynamically adjusted. When the electrified wire netting IR-drop and wind velocity changes, a comparative analysis of the dynamic tuning PI controller parameters and the non-dynamic tuning method was conducted. At last, the simulation studies have shown that the constant voltage control system using the PI parameter Flexible adjustment control method found on ACO can rapidly improve the grid voltage stability of double-fed wind turbines and reduce response time.

Automated air pressure control system in a motorised breathing apparatus

The relevance of the study is to develop an effective system for controlling the pressure in the air supply in motorised breathing apparatus to ensure effective protection of employees from dangerous aerosols and improve their health. The goal was to create an automated air pressure control system in a motorised breathing apparatus using a proportional-integral-derivative controller. For this purpose, the simulation method was used. In order to avoid unforeseen situations of deterioration of the level of protection, the structure of the pressure control system of a motorised respirator has been developed with the selection of the appropriate controller based on the obtained dependences of the influence of the parameters of the breathing mode and the amount of pressure in the under-mask space of the respirator, which ensures an appropriate comfortable mode of operation. This allowed developing a simulation model with a PID controller that would provide the appropriate pressure values within the permissible limits (50-370 Pa). It is proved that the proportional-integral-derivative controller maintains the pressure in the respirator mask within certain limits both with an increase and with a decrease in the control signal, preventing excessive fluctuations in the controlling variable, which leads to an extension of the service life of the filter elements and a reduction in electricity consumption for the operation of the fan motor. Based on modelling the operation of the pressure control system in different modes of operation, it is shown that when using a PID controller with defined parameters, the system provides compensation for changes in air pressure in the under-mask space of the respirator in different breathing modes of the user. The results can find practical applications in the field of safety and health, in industrial environments where workers are at risk of inhaling dangerous aerosols, such as toxic particles, gases, or other harmful substances

The Influence Of Competence, Independence, Obedience Pressure, And Internal Control System On The Quality Of Internal Auditor Examination Results

This study aims to test and find empirical evidence of the effect of Competence, Independence, Obedience Pressure, and Internal Control Systems on the quality of internal auditor examination results. The population in this study were all civil servants (PNS) in the Inspectorate of Bengkulu Province, totaling 130 people. Sampling in this study uses non-probability sampling through purposive sampling, where all examiners who occupy the Auditor Functional Position (JFA) and P2UPD Functional Position at the Inspectorate of Bengkulu Province are used as a sample of 96 people. The data analysis model used in this research is multiple linear regression analysis using IBM SPSS version 25 software. The findings reveal that competence, independence, and the internal control system positively influence examination quality, while obedience pressure has a negative impact. The implication of this research is that it provides an opportunity for the inspectorate of the province of Bengkulu to pay more attention to factors that can improve the quality of examination results such as increasing auditor competence, strengthening auditor independence, how to overcome obedience pressure and strengthen and ensure an effective internal control system.

Dual network control system for bottom hole throttling pressure control based on RBF with big data computing

Dual network control system for bottom hole throttling pressure control based on RBF with big data computing

Modeling of the curvilinear motion of a vehicle with all steer wheels

Developed simulation model of the curvilinear motion of the two-axial wheel carrier with all steer wheels. The model includes the motion of the wheel carrier’s center of mass with respect to the moving coordinate system, the matrix of the directional cosines for the transition from a moving to the fixed coordinate system, the bearing and running module for the determination of the reactions in the flat spot of the wheel tire with the bearing surface area, and the mechanism for turning steer wheels. The aim is to study vehicle steerability and dexterity of the two-axial wheel carrier with all steer wheels via modeling in the MATLAB Simulink. Parameters obtained show the application effectiveness of the steering control with all steer wheels for the two-axial wheel carrier. Results obtained can be applied to the constructional design of a vehicles for the determination of the optimal parameters of a steering configuration. Developed simulation model of the vehicle can become a basis for the modeling of vehicles’ motion equipped with the control system of the air pressure in tires, track-type module, adaptive undercarriages with the robotic operating system, etc.

Dual network control system for bottom hole throttling pressure control based on RBF with big data computing

Dual network control system for bottom hole throttling pressure control based on RBF with big data computing

An improved AO algorithm optimized PID rectification model for wind speed and wind pressure regulation in video cabinet of tobacco sorting machine

Abstract Sorting and removing impurities is the use of raw materials and light impurities suspended speed differences through the wind to separate the hemp, paper, plastic, and other light materials to remove impurities. Article to tobacco sorting machine video cabinet wind pressure control system principle as a guide, combined with the structure of the sorting and impurity removal machine and the principle of wind speed balance designed to balance the wind speed and wind pressure of the tobacco sorting machine. The control model of wind speed and pressure in the video cabinet system of the tobacco sorting machine is established, and the improved AO algorithm is used for the design of the overall PID controller and optimization of the PID controller’s setting parameters. The IAO algorithm optimizes the parameters of the PID setting controller with a steady state error within 3%, and the introduction of the IAO-PID controller can make the wind speed of the sorting machine system control from 16.4m/s to 11.1m/s within 17ms. When the system detects that the negative pressure of wire feeding changes sharply to about 1.12MPa within 20ms and exceeds the differential pressure start value of 0.9MPa set by the sorter system, the tobacco wire feeding anti-clogging function is activated. The PID controller optimized by the IAO algorithm can achieve precise regulation and control of wind speed and pressure of tobacco sorting machines, improving the sorting efficiency of tobacco production.

Perancangan Sistem Kontrol Tekanan Pada Reaktor Biogas Berbasis PID Controller dengan Ziegler-Nichols dan Auto Tuning PSO

Biogas, an eco-friendly energy source, significantly reduces greenhouse gas emissions by converting organic waste or biomass into methane. However, the quality of biogas, primarily determined by methane content and pressure variables, directly impacts its efficiency and safety. This study, which aims to design a pressure control system and monitor methane gas levels in a biogas reactor using a PID Controller with Particle Swarm Optimization (PSO), provides crucial insights into improving biogas production efficiency and safety. Tests were conducted on a fixed dome-type biogas reactor in the East Java region, Indonesia. The PSO-based PID tuning was compared with two other PID tuning methods: Trial-error and Ziegler-Nichols (ZN). Data on pressure values and biogas flow rates from the biogas reactor were collected, and system modeling was carried out to produce a system transfer function. The PSO algorithm was developed to optimize PID control parameters. The results of this research demonstrate that the PID tuning method using PSO produces a stable state error value of 1.40%, rise time of 0.09 s, settling time of 2.1 s, maximum overshoot of 0.986404, and ITAE of 0.0010801. The implementation of PID-PSO can significantly enhance PID control performance in rise time, settling time, maximum overshoot, and ITAE compared to Trial-Error and ZN, while the stable state error value in PID-PSO tuning is higher than tuning using Trial-Error and ZN.