A Multivariable Self-tuning Controller for a D-type Water Tube Industrial Boiler (original) (raw)
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JAREE (Journal on Advanced Research in Electrical Engineering), 2021
A control system with uncertainty or unpredictable disturbance needs more effort to be controlled. A conventional PID Controller is the most popular method used in industries. It was tuned and adjusted by the designer, and it has fixed parameters during operation. However, the disturbance effect causes the desired system performance unreachable. By using a self-tuning controller, the problem should be tackled. In this paper, the PID-Genetic Algorithm (PID-GA) controller was proposed and tested with the steam drum water level control system of a steam power plant. Variation in power load causes noisy water level characteristics and should be maintained at + 0.4 meters from the setpoint to prevent the power plant trip. From the simulation, PID-GA can reduce disturbance of the minimum, nominal, and maximum load with perturbation peaks 0.18 m, 0.22 m, and 0.26 m respectively.Keywords: genetic algorithm, NWL, PID-GA, steam drum, steam power plant.
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Abstract— This work aims to present an application of water level control system for a three-element cascade drum boiler with a PID controller. The PID control value was divided into two control ranges, including peak mode operation during high power consumption and off-peak mode operation during low power consumption for a combined cycle power plant. The feedforward part was the flow rate, while the feedback part was the water level in the drum boiler. Such variables consisted of steam output flow rate, feed water flow rate and water level in the drum boiler. The optimization method was applied for calculating the parameters of the water level controller in the drum boiler. As a result, it was found that the PID controller with divided control phases was able to clearly control the water level of the drum boiler better than a single PID controller. It was able to handle transient and rapid processes very well. For example, shrink and swell effects of water in a drum boiler caused b...
Advanced control system of the steam pressure in a fire-tube boiler
IFAC Proceedings Volumes (IFAC-PapersOnline), 2008
The urgent requirement to optimize the consumption of energetic resources justifies the application of advanced control strategies to automate equipment that consumes higher amounts of fossil fuels, among them the fire-tube boilers. From a control engineering point of view, these systems are characterized by a difficult dynamic behavior, multiple inputs and outputs, time delay and several uncertainties. In this work an advanced control system with an Adaptive-GPC algorithm of the steam pressure inside a fire-tube boiler is presented. System identification techniques were employed to obtain a mathematical model that characterizes the dynamic behavior of the process under study. Simulation results evidenced that this model describes with high exactitude the process of steam pressure variation inside the boiler. The model obtained was subsequently used to design the advanced control system. The system was implemented in a utility fire-tube boiler and the results showed its efficiency to deal with variations of the dynamic parameters of the process arisen at different operating conditions. It also showed its superiority against a control system using a PID algorithm.
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Fire tube shell boiler is probably one of the most widely used boilers in the process industries and residential areas for process heating and steam/hot water supply. To achieve optimal design and operation of these plants, precise control system design is required.
2019
The water level in the steam drum needs to be kept constant at a certain point. Therefore, control is needed for the flow rate of incoming water feedwater to adjust to the disruption of the steam flow rate that comes out. The size of the steam flow rate that comes out depends on the load demand. If the demand for loads is high and fluctuations, then the water level in the steam drum will be more difficult. The PID type fuzzy logic controller with a robust self-tuning scheme will be implemented in the water level regulation system in the steam drum. In the three-element control scheme, when given a high load of 700 MW the system produces an error deviation of 15.69 mm peak against the set point. This value is smaller than the single-element control scheme by producing an error deviation of 18.5 mm against the set point. However, when given a set point change of 40 mm the three-element control scheme produced a response of 16.82 mm peak error error to the set point. This value is grea...
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The three-pulse system of automatic control of the water level in the boiler drum received maximum distribution in the energy sector, as well as its modifications, which have the following disadvantages : the presence of static control errors at the end of the transition process in the development of internal disturbances and disturbances of superheated steam flow; large level deviations with sharp and significant changes in the load, which often leads to unloading or shutdown of the boiler or power unit. To eliminate these drawbacks, invariant systems for automatic regulation of the power supply of the drum boiler were previously developed. In work the system of automatic control of technological parameters of water level in a drum of steam boilers is considered. The description of control systems and a detailed description of the electrical power systems of the control system are given. Various methods of tuning the PI controller of a typical three-pulse automatic power control sy...
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Invariant Method of Load Independent Pressure Control in Steam Boiler
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The paper considers the possibility of steam production and supply process improvement by perfection of the steam boiler control system, applying invariance principle that makes possible preemptive compensation of the influence of steam expenditure as a disturbance on the control process quality and efficiency. For the development of invariant control system, the mathematical modeling and simulation in MATLAB-SIMULINK environment is made. The control unit is low pressure steam boiler with one input impact to control -the heat flow of burning gas mixture fuel, one measured output parameter of the process -the steam pressure, and the main disturbance as a load impact -the steam expenditure. The mathematical and virtual models and block-diagrams for transient process simulation is compiled, allowing to start practical design and investigation of steam boiler invariant control system with high operation stability under essentially fluctuating load. The simulation results prove that the optimal solution for the transient process improvement in steam boiler, taking in account fluctuating load, is invariant PID-DPC two loop control system with disturbance impact on steam pressure preemptive compensation. Under invariant control the steam pressure overshoots decreases substantially in comparison with the traditional PID-feedback control method.
Design of Automatic Control System of Hot Water Boiler based on PI & PID Controller | IJSRDV6I90046
IJSRD - International Journal for Scientific Research and Development, 2018
— Even though PID controller is one of the most commonly used controllers they pose issues such as it is not easy to tune PID controller's parameters and they usually have a slow response time when handling large systems like boilers. So in this study a Model Driven PID controller is designed particularly focusing on addressing the slower response time issue. The control characteristics of the Model Driven PID controller are compared against the conventional PI controller.