Efficiencies and Required Power Extraction Ratios for Closed-Cycle MPD Power Systems

1987 ◽  
Author(s):  
M. E. Talaat
Keyword(s):  
Power Systems ◽  
Closed Cycle ◽  
Power Extraction

scholarly journals 5 MW Closed Cycle Gas Turbine

1984 ◽  
Author(s):  
John L. Mason ◽  
Anthony Pietsch ◽  
Theodore R. Wilson ◽  
Allen D. Harper
Keyword(s):  
Power Systems ◽  
Gas Turbine ◽  
Oil Recovery ◽  
Low Cost ◽  
Pressure Ratio ◽  
Commercial Application ◽  
Solid Fuels ◽  
Closed Cycle ◽  
Emission Standards ◽  
Fluidized Bed Combustor

A novel closed-cycle gas turbine power system is now under development by the GWF Power Systems Company for cogeneration applications. Nominally the system produces 5 megawatts (MW) of electric power and 80,000 lb/hr (36,287 kg/hr) of 1000 psig (6895 kPa) steam. The heat source is an atmospheric fluidized bed combustor (AFBC) capable of using low-cost solid fuels while meeting applicable emission standards. A simple, low-pressure ratio, single spool, turbomachine is utilized. This paper describes the system and related performance, as well as the development and test efforts now being conducted. The initial commercial application of the system will be for Enhanced Oil Recovery (EOR) of the heavy crudes produced in California.

scholarly journals Simulation of industrial solar photovoltaic station with transformerless converter system

2020 ◽  
pp. 73-79
Author(s):  
D. V Tugay ◽  
S. I Korneliuk ◽  
O. O Shkurpela ◽  
V. S Akimov
Keyword(s):  
Power Systems ◽  
Thermal Characteristics ◽  
Maximum Power ◽  
Photovoltaic Module ◽  
Solar Photovoltaic ◽  
Systems Methodology ◽  
Detailed Model ◽  
Power Extraction ◽  
Solar Radiation Intensity ◽  
Multi Level

Purpose. Creation of a detailed model of a solar photovoltaic station with a converter system based on a cascaded multi-level inverter with the MPPT (maximum power point tracker) function to investigate its operating modes in distributed power systems. Methodology. To carry out the research, the paper used the methods of system synthesis, mathematical and computer modeling to create photovoltaic station models and components; a physical experiment in obtaining thermal characteristics of the photovoltaic module Solarday SDM72360 W; modern power theories for synthesis of the vector control system of a multi-level inverter. Findings. the Matlab-model of solar photovoltaic station with transformerless 29-level cascade voltage inverter is synthesized. The model confirmed the serviceability and efficiency of the converter system and the power plant as a whole. An algorithm is proposed and an MPP tracker with volt-ampere characteristics of the photovoltaic module, which corresponds to the maximum power extraction, is synthesized on the basis of the algorithm. The algorithm was validated by the model for any solar radiation intensity. Originality. The total mathematical model of the photoelectric module, which accounts for its energy and heat characteristics, is obtained and can be used for simulating the operation of any computer model of the photoelectric converter under Matlab/Simulink/SimPowerSystems environment. Practical value. The model results indicate the prospects of industrial implementation of transformerless multi-level converter systems to be used in the structure of powerful solar photovoltaic stations.

State-of-the-Art Review of Closed Cycle Gas Turbines Burning Dirty Fuels

1983 ◽  
Author(s):  
G. E. Provenzale
Keyword(s):  
Power Systems ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Detailed Examination ◽  
Full Potential ◽  
Development Programs ◽  
Closed Cycle ◽  
Cost Information ◽  
Steam Power ◽  
Critical Components

The Closed Cycle Gas Turbine (CCGT) offers potential savings in operating costs due to high system efficiency and the ability to direct fire coal. However, for the full potential of CCGT to be realized, more competitive cost information must be generated, correlated, and compared with conventional steam power systems. Current development programs are intended to resolve many of the remaining uncertainties in design, performance, and cost by detailed examination and testing of critical components of CCGT coal-fired power systems. This paper reviews current technology developments and economic considerations of the closed cycle gas turbine burning dirty fuels versus conventional steam power systems.

The Nuclear Gas Turbine: Towards Realization After Half a Century of Evolution

1995 ◽  
Author(s):  
Colin F. McDonald
Keyword(s):  
Power Systems ◽  
Gas Turbine ◽  
Nuclear Reactor ◽  
Electrical Power ◽  
District Heating ◽  
Small Scale ◽  
Closed Cycle ◽  
Furnace Gases ◽  
The Usa ◽  
Space Power Systems

This paper has been written exactly 50 years after the first disclosure of a closed-cycle gas turbine concept with a simplistic uranium heater. Clearly, this plant was ahead of its time in terms of technology readiness, and the closed-cycle gas turbine was initially deployed in a cogeneration mode burning dirty fuels (e.g., coal, furnace gases). In the 1950s through the mid 1980s about 20 of these plants operated providing electrical power and district heating for European cities. The basic concept of a nuclear gas turbine plant was demonstrated in the USA on a small scale in 1961 with a mobile closed-cycle nitrogen gas turbine [330 KW(e)] coupled with a nuclear reactor. In the last three decades, closed-cycle gas turbine research and development, particularly in the U.S. has focused on space power systems, but today the utility size gas turbine-modular helium reactor (GT-MHR) is on the verge of being realized. The theme of this paper traces the half century of closed-cycle gas turbine evolution, and discusses the recent enabling technologies (e.g., magnetic bearings, compact recuperator) that now make the GT-MHR close to realization. The author would like to dedicate this paper to the late Professor Curt Keller who in 1935 filed the first closed-cycle gas turbine patent in Switzerland, and who exactly 50 years ago, first described a power plant involving the coupling of a helium gas turbine with a uranium heater.

SECONDARY POWER SYSTEM EVALUATIONS FOR ADVANCED AIRCRAFT

1999 ◽  
Vol 23 (1B) ◽  
pp. 117-127
Author(s):  
R. Lykins ◽  
M. Ramalingam ◽  
B. Donovan ◽  
E. Durkin ◽  
J. Beam
Keyword(s):  
Power Systems ◽  
Power System ◽  
Data Transfer ◽  
Engine Performance ◽  
Air Power ◽  
Power Extraction ◽  
Resultant Data ◽  
Shaft Power ◽  
The Impact ◽  
Engine Cycle

A computerized analytical program is being developed to help investigate the impact of power system requirements on aircraft performance. The program has an user interface that operates in MS-EXCEL, linking several subsystems analysis programs for execution and data transfer in the power systems analysis. The program presently includes an encoded propulsion engine cycle code, which allows the inspection of power extraction effects on engine performance. To validate the results of the encoded engine program, a study was conducted to investigate the separate effects of shaft power extraction and pneumatic bleed. The selected engine cycle was that for a standard tactical fighter, with a flight condition of varied altitude (sea level to 40,000 ft) and constant Mach Number (0.9). As expected the resultant data showed that the engine performance was more sensitive to pneumatic bleed than to shaft power extraction. The paper’s efficiency comparisons between shaft power and bleed air power helps indicate the higher efficiency for the power system of a more-electric type aircraft. Present efforts on the analytical interface are to incorporate a fuel thermal management analysis capability.

Applying Combined Pinch and Exergy Analysis to Closed-Cycle Gas Turbine System Design

1995 ◽  
Vol 117 (1) ◽  
pp. 47-52 ◽  
Author(s):  
V. R. Dhole ◽  
J. P. Zheng
Keyword(s):  
Power Systems ◽  
Gas Turbine ◽  
Gas Turbines ◽  
Power Plants ◽  
Exergy Analysis ◽  
Energy Savings ◽  
Design Guidelines ◽  
Closed Cycle ◽  
Practical Design ◽  
Pinch Technology

Pinch technology has developed into a powerful tool for thermodynamic analysis of chemical processes and associated utilities, resulting in significant energy savings. Conventional pinch analysis identifies the most economical energy consumption in terms of heat loads and provides practical design guidelines to achieve this. However, in analyzing systems involving heat and power, for example, steam and gas turbines, etc., pure heat load analysis is insufficient. Exergy analysis, on the other hand, provides a tool for heat and power analysis, although at times it does not provide clear practical design guidelines. An appropriate combination of pinch and exergy analysis can provide practical methodology for the analysis of heat and power systems. The methodology has been successfully applied to refrigeration systems. This paper introduces the application of a combined pinch and exergy approach to commercial power plants with a demonstration example of a closed-cycle gas turbine (CCGT) system. Efficiency improvement of about 0.82 percent (50.2 to 51.02 percent) can be obtained by application of the new approach. More importantly, the approach can be used as an analysis and screening tool for the various design improvements and is generally applicable to any commercial power generation facility.

Underwater Power From Aluminum

1968 ◽  
Vol 90 (2) ◽  
pp. 255-260 ◽  
Author(s):  
F. H. Bobb
Keyword(s):  
Power Systems ◽  
Low Temperatures ◽  
Sea Water ◽  
Combustion Process ◽  
Prime Mover ◽  
Closed Cycle ◽  
Design Concepts ◽  
Reaction Test ◽  
Open Cycle ◽  
Deep Depth

A thermochemical power system having the highest theoretical performance (hp-hr/cu ft propellants) and particularly suited for underwater applications (power, heat, and propulsion) is described. In this system aluminum is reacted exothermally with sea-water to produce gaseous exhaust products, hydrogen-and steam. The exhaust products are expanded through a prime mover to produce shaft horsepower, or a combustion process can be added before the prime mover to convert the hydrogen to steam for applications that require condensable exhaust products. Open cycle (shallow depth operation) and closed cycle (deep depth operation) systems are described. The technique for reacting aluminum and water at low temperatures is discussed and aluminum-water reaction test data are presented. Design concepts of practical systems are shown, and typical power systems are compared relative to total energy, volume, and weight.

scholarly journals Power Extraction Control of Variable Speed Wind Turbine Systems Based on Direct Drive Synchronous Generator in All Operating Regimes

2018 ◽  
Vol 2018 ◽  
pp. 1-17 ◽  
Author(s):  
Youssef Errami ◽  
Abdellatif Obbadi ◽  
Smail Sahnoun ◽  
Mohammed Ouassaid ◽  
Mohamed Maaroufi
Keyword(s):  
Power Systems ◽  
Control Strategy ◽  
Wind Farm ◽  
Electrical Power ◽  
Synchronous Generator ◽  
Performance Comparison ◽  
Direct Drive ◽  
Power Extraction ◽  
Wide Range ◽  
Farm System

Due to the increased penetration of wind energy into the electrical power systems in recent years, the turbine controls are actively occupied in the research. This paper presents a nonlinear backstepping strategy to control the generators and the grid sides of a Wind Farm System (WFS) based Direct Drive Synchronous Generator (DDSG). The control objectives such as Tracking the Maximum Power (TMP) from the WFS, pitch control, regulation of dc-link voltage, and reactive and active power generation at varying wind velocity are included. To validate the proposed control strategy, simulation results for 6-MW-DDSG based Wind Farm System are carried out by MATLAB-Simulink. Performance comparison and evaluation with Vector Oriented Control (VOC) are provided under a wide range of functioning conditions, three-phase voltage dips, and the probable occurrence of uncertainties. The proposed control strategy offers remarkable characteristics such as excellent dynamic and steady state performance under varying wind speed and robustness to parametric variations in the WFS and under severe faults of grid voltage.

scholarly journals Validation of Novel PLL-driven PI Control Schemes on Supporting VSIs in Weak AC-Connections

Energies ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1373 ◽  
Author(s):  
Panos C. Papageorgiou ◽  
Konstantinos F. Krommydas ◽  
Antonio T. Alexandridis
Keyword(s):  
Power Systems ◽  
Stability And Convergence ◽  
Voltage Source ◽  
Phase Locked Loops ◽  
System Management ◽  
Long Distance ◽  
Voltage Source Inverters ◽  
Power Extraction ◽  
Control Schemes ◽  
Stable Performance

The integration of distributed energy resources (DERs) in modern power systems has substantially changed the local control capabilities of the grid since the majority of DERs are connected through a controlled dc/ac inverter interface. Such long-distance located DER installations, usually represented by current regulated dc sources, can inject large amounts of power into the main ac grid at points where the strength of the ac connection is low. The efficient and stable performance of such a power scheme is related to the capability of the control applied to retain the power extraction close to the maximum and simultaneously to regulate the dc-side voltage as well as the ac-side voltage magnitude at the weak ac connection point. This is implemented by designing the controllers of the voltage source inverters (VSIs) in a manner that reliably satisfies the above tasks. To this end, decentralized cascaded control schemes, driven by novel, locally implemented phase locked loops (PLLs), suitable to work in weak ac connections, are proposed for the VSI performance regulation by using new fast inner-loop proportional-integral (PI) current controllers. A decisive innovation is proposed by inserting an extra damping term in the inner-loop controllers to guarantee stability and convergence to the desired equilibrium. This is analytically proven by a rigorous analysis based on the entire nonlinear system model, where advanced Lyapunov-based methods are deployed in detail. As a good transient response of the VSI interface is indeed critical for the energy and grid system management, the conducted simulation and experimental results confirm that the proposed scheme efficiently supports the ac- and dc-side voltages of the VSI under different varying conditions in the power production or any voltage changes of the main grid.

Sign in / Sign up

Export Citation Format

Share Document