scholarly journals Development of a Dynamic Model and Control System for Load-Following Studies of Supercritical Pulverized Coal Power Plants

Processes ◽  
2018 ◽  
Vol 6 (11) ◽  
pp. 226 ◽  
Author(s):  
Parikshit Sarda ◽  
Elijah Hedrick ◽  
Katherine Reynolds ◽  
Debangsu Bhattacharyya ◽  
Stephen E. Zitney ◽  
...  
Keyword(s):  
Control System ◽  
Dynamic Model ◽  
Power Plants ◽  
Pulverized Coal ◽  
Servo Control ◽  
Regulatory Control ◽  
Software Environment ◽  
Feed Composition ◽  
Load Following ◽  
The Impact

Traditional energy production plants are increasingly forced to cycle their load and operate under low-load conditions in response to growth in intermittent renewable generation. A plant-wide dynamic model of a supercritical pulverized coal (SCPC) power plant has been developed in the Aspen Plus Dynamics® (APD) software environment and the impact of advanced control strategies on the transient responses of the key variables to load-following operation and disturbances can be studied. Models of various key unit operations, such as the steam turbine, are developed in Aspen Custom Modeler® (ACM) and integrated in the APD environment. A coordinated control system (CCS) is developed above the regulatory control layer. Three control configurations are evaluated for the control of the main steam; the reheat steam temperature is also controlled. For studying servo control performance of the CCS, the load is decreased from 100% to 40% at a ramp rate of 3% load per min. The impact of a disturbance due to a change in the coal feed composition is also studied. The CCS is found to yield satisfactory performance for both servo control and disturbance rejection.

Grid-Connected Nuclear Power Plant Key Issues Summary

2014 ◽  
Vol 521 ◽  
pp. 530-535
Author(s):  
Meng Wang ◽  
Jian Ding ◽  
Tian Tang ◽  
Zhang Sui Lin ◽  
Zhen Da Hu ◽  
...  
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Large Scale ◽  
Power Modeling ◽  
Modeling Simulation ◽  
Load Following ◽  
Key Issues ◽  
The Impact

The current situation of nuclear power plants at home and abroad is described, and the impact of large-scale nuclear power accessing to the grid is analyzed, specifically in the aspects of nuclear power modeling, simulation, load following, reliability, fault diagnosis, etc. Nuclear power accessing to the grid will bring a series of problems, the causes of each problem, the main solutions and future development directions are summarized.

scholarly journals Relationship between Particle Size Distribution of Low-Rank Pulverized Coal and Power Plant Performance

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Rajive Ganguli ◽  
Sukumar Bandopadhyay
Keyword(s):  
Particle Size ◽  
Power Plant ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Power Plants ◽  
Pulverized Coal ◽  
Plant Performance ◽  
Low Rank ◽  
Volatile Content ◽  
The Impact

The impact of particle size distribution (PSD) of pulverized, low rank high volatile content Alaska coal on combustion related power plant performance was studied in a series of field scale tests. Performance was gauged through efficiency (ratio of megawatt generated to energy consumed as coal), emissions (SO2,NOx, CO), and carbon content of ash (fly ash and bottom ash). The study revealed that the tested coal could be burned at a grind as coarse as 50% passing 76 microns, with no deleterious impact on power generation and emissions. The PSD’s tested in this study were in the range of 41 to 81 percent passing 76 microns. There was negligible correlation between PSD and the followings factors: efficiency, SO2,NOx, and CO. Additionally, two tests where stack mercury (Hg) data was collected, did not demonstrate any real difference in Hg emissions with PSD. The results from the field tests positively impacts pulverized coal power plants that burn low rank high volatile content coals (such as Powder River Basin coal). These plants can potentially reduce in-plant load by grinding the coal less (without impacting plant performance on emissions and efficiency) and thereby, increasing their marketability.

Nuclear Power Plant Flexible Power Operation Capability Analysis

2017 ◽  
Author(s):  
Ye Cheng ◽  
Wang Minglu ◽  
Qiu Zhongming ◽  
Wang Yong
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Renewable Energy Sources ◽  
Frequency Regulation ◽  
Operational Mode ◽  
Load Following ◽  
Capability Analysis ◽  
Power Operation ◽  
The Impact

Nuclear power plants are used extensively as base load sources of electricity. This is the most economical and technically simple mode of operation. In this mode, power changes are limited to frequency regulation for grid stability purposes and shutdowns for safety purposes. However for countries with high nuclear shares or desiring to significantly increase renewable energy sources, the question arises as to the ability of nuclear power plants to follow load on a regular basis, including daily variations of the power demand. This paper give a detailed analysis of the technical and economic aspects of load-following with nuclear power plants, and summaries the impact of load-following on the operational mode.

scholarly journals Synthesis of control system with guaranteed accuracy for unmanned aircraft

2020 ◽  
pp. 66-70
Author(s):  
О.В. Збруцький ◽  
А.С. Довгополий ◽  
О.Е. Кописов ◽  
O.O. Білобородов
Keyword(s):  
Adaptive Control ◽  
Control System ◽  
Dynamic Model ◽  
Unmanned Aerial Vehicle ◽  
Synthesis Method ◽  
Actual State ◽  
Forecast Horizon ◽  
Guaranteed Accuracy ◽  
Aerial Vehicle ◽  
The Impact

Unmanned aerial vehicle must be controllable and fend off disturbing influences. The quality and effectiveness of fulfilling these tasksare completely determined by the instrumentation system and the software of the control system, which ensures the safety and reliability of the unmanned aerial vehicle. The synthesis of adaptive control algorithms in the presence of disturbances in most cases suggests the use of a certain disturbance model and is associated with the use of integral regulators, which increases the order of the system, and sometimes they are substantially non-linear. Adaptive algorithms use both predictive methods for assessing the dynamics of an object. For the synthesis of the control system, was considered the dynamic model of an unmanned aerial vehicle as a solid. Then the linearized equations of transverse motion can be represented by a system of differential equations. The study performed the synthesis of control system regulators by integrating the equations of the dynamic model of the object for a given control program, made a forecast of the movement of an unmanned aerial vehicle for a certain final period of time. By optimization of program control, was taking into account the restrictions imposed on the control and adjustable variables, the adjustable variables of the forecasting model approach the corresponding control signals on the forecast horizon. At the calculation step, which is a fixed small part of the forecast horizon, the optimal control found was realized and the actual state of the unmanned aerial vehicle was measured at the end of the step. The forecast horizon moves forward one step, and this procedure is repeated. The efficiency of the model predictive control as synthesis method for unmanned aerial vehicle’s control system is analyzed. A new synthesis method of adaptive control system with guaranteed accuracy under an arbitrary external disturbance is shown. The method is based on evaluating the effect of disturbances, predicting the behavior of the system and compensating the impact on the control object by the formation of a law for changing the parameters of the additional controller, which does not directly affect the quality of the control system.The results of control system’s mathematical modeling for aircraft and multicopter types of unmanned aerial vehicles are presented.

Simulation of Ancillary Services in Thermal Power Plants in Energy Systems With High Impact of Renewable Energy

2017 ◽  
Author(s):  
Moritz Huebel ◽  
Conrad Gierow ◽  
Jens Hinrich Prause ◽  
Sebastian Meinke ◽  
Egon Hassel
Keyword(s):  
Renewable Energy ◽  
Control System ◽  
Power Plants ◽  
Thermal Power ◽  
Ancillary Services ◽  
Electricity Production ◽  
Thermal Power Plants ◽  
Secondary Control ◽  
Primary And Secondary Control ◽  
The Impact

In many parts of the world, the impact of renewable energy, especially from intermittent sources as wind and solar is continuously increasing. In Germany, the share of renewable energy in electricity production is believed to increase from 32.5% in 2015 to 50% in 2030. In order to operate an electrical system and control the mains frequency, the power supply must match the consumption at any time. Ancillary services like primary and secondary control are used to balance the system on a time-scale of several seconds up to 15 minutes. Those control reserves are usually provided by thermal power plants. Particularly in times of high shares of fluctuating renewable feed-in, thermal power plants are turned off or operated at minimum load to avoid electricity production at low electricity prices. However, an amount of about 3000 MW of fast responding primary control need to be provided in the European network of transmission system operators for electricity grid to maintain stable operation even in case of two simultaneous large unit outages. This requirement leads to situations, where thermal power plants are operated in minimum load below their marginal cost to provide control reserves even if there is a surplus of energy in the grid. Operation in low load while at the same time providing control reserves leads to new challenges. As the relation between energy production and the thermal storage capacities provided by the metal and fluid mass in the boiler is decreasing with the load, the ability of responding to control demands is naturally slowed down. Dynamic simulation of the thermodynamic power plant process turned out to be an efficient method to investigate such operational modes. Using comprehensive process models coupled with a control system model, equipment adaptions or control system updates can be evaluated in order to provide faster responses. By increasing the specific amount of ancillary services per unit, the number of units necessary to provide the total amount of primary and secondary control could be reduced in situations with energy surplus.

scholarly journals TRANSITION OF PULVERIZED COAL BOILERS TПП-210A OF TRУPILLIA POWER PLANT TO BURNING SOLID FUEL WITH TECHNICAL CHARACTERISTICS DIFFERENT FROM THE PROJECT ONES

2017 ◽  
pp. 4-8
Author(s):  
Yo.S. Mysak ◽  
T.Yu. Kravets ◽  
S.Yo. Mysak ◽  
D.D. Shatylo ◽  
E.N. Yakymiv
Keyword(s):  
Power Plant ◽  
Solid Fuel ◽  
Power Plants ◽  
Pulverized Coal ◽  
Lean Coal ◽  
The Impact ◽  
First Time

As a consequence of combatting actions in the east of Ukraine there has been a reduction of supply of Donetsk anthracite and lean coal to power plants that used it as the main fuel. That is why in work, for the first time, they managed to resolve scientific and practical problems, in particular, ensure the possibility of safe and economic burning of solid fuel with technical characteristics different from the project ones in boilers of Trypillia power plant. The provided results of tests of the boiler ТПП-210А in the range of loads from 331/334 t/hour to 499/500 t/hour (respectively body A/body Б) in two-body mode of work and with load of 415 t/hour in one-bode mode when burning fuel with technical characteristics different from the project ones (coal imported from the Southern African Republic) allowed to determine the impact of the excess of air in mode crossing on the boiler’s work, and correct the mode map of its work. Bibl. 3, Fig. 3.

АКУСТИЧНА ПОМІТНІСТЬ БЕЗПІЛОТНИХ ЛІТАЛЬНИХ АПАРАТІВ З СИЛОВИМИ УСТАНОВКАМИ НА БАЗІ ПОРШНЕВИХ ДВИГУНІВ

2020 ◽  
pp. 62-80
Author(s):  
В. В. Руденко ◽  
И. В. Калужинов ◽  
Н. А. Андрущенко
Keyword(s):  
Control System ◽  
Internal Combustion Engine ◽  
Power Plants ◽  
Combustion Engine ◽  
Spectral Characteristics ◽  
Experimental Studies ◽  
Internal Combustion ◽  
Detection Range ◽  
Acoustic Signature ◽  
Static Conditions

The presence in operation of many prototypes of UAVs with propeller propellers, the use of such devices at relatively low altitudes and flight speeds makes the problem of noise reduction from UAVs urgent both from the point of view of acoustic imperceptibility and ecology.The aim of the work is to determine a set of methods that help to reduce the visibility of UAVs in the acoustic range. It is shown that the main source of noise from the UAV on the ground is the power plant, which includes the engine and the propeller. The parameters of the power plants influencing the processes that determine the acoustic signature of the UAV were investigated. A comprehensive analysis of the factors affecting visibility was carried out. The power plants include two-stroke and four-stroke engines, internal combustion and two-blade propellers. The use of silencers on the exhaust of the internal combustion engine was considered. The spectral characteristics of the acoustic fields of the propeller-driven power plants for the operating sample of the UAV "Eco" were obtained. The measurements were carried out in one-third octave and 1/48 octave frequency bands under static conditions. The venue is the KhAI airfield. Note that the propellers that were part of the power plants operated at Reynolds numbers (Re0,75<2*105), which can significantly affect its aerodynamic and acoustic characteristics. It is shown that when choosing a UAV control system, one should take into account the fact that two-stroke piston engines are the dominant source in the noise of propeller-driven control systems in the absence of a hood and mufflers in the intake and exhaust tracts. The use of a four-stroke internal combustion engine significantly reduces the noise of the control system. In the general case, the position of the boundaries of the zone of acoustic visibility of a UAV at the location of the observer is determined by the ratio between the intensity of acoustic radiation perceived by the observer from the UAV and the intensity of sound corresponding to the natural acoustic background and depends on the degree of manifestation of acoustic effects accompanying the propagation of sound in a turbulent atmosphere - the refraction of sound waves. Absorption and dissipation of acoustic energy. The calculation and comparison of the UAV detection range was carried out taking into account the existing natural maskers.The results of experimental studies are presented that allow assessing the degree of acoustic signature of the UAV. A set of measures aimed at reducing the intensity of the acoustic signature of the UAV in various regions of the radiation spectrum has been determined.

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