The gasifier is an important component of energy sources. It is a typical nonlinear and coupled multivariable system with strict actuator saturation constraints. To handle with these challenges, an ...ALSTOM gasifier benchmark problem is proposed for controller design and control performance comparisons. A new control structure combining active disturbance rejection control (ADRC) and an actuator rate limit compensation is proposed for this benchmark problem in this paper. The corresponding design procedures for the proposed control structure are provided. Its superiority over other control structures is verified by extensive simulations and comparative experiments where the proposed control structure is the least sensitive to the rate limit uncertainty. The superiorities of the proposed control structure under the nominal condition and uncertain rate limit conditions are verified for the benchmark problem, where the average control performance indices of the proposed control structure are no more than 90.0% of the comparative control strategy for all loops under the nominal condition and the average ranges of the proposed control structure are no more than 7.0% of the comparative control strategy when the rate limit is perturbed in ±35% of the nominal value. In general, the proposed control structure is able to obtain satisfactory control performance and has a strong ability to handle rate limit uncertainties, while the comparative control strategy cannot guarantee the convergence of the gasifier system. ADRC with actuator rate limit compensation clearly has a great potential in industrial applications.
•An active disturbance rejection control structure with rate limit compensation is proposed.•The superiorities of the proposed structure are investigated by comparative experiments.•The ALSTOM gasifier system with the proposed structure obtains satisfactory control performance.
A new control solution based on a unique active disturbance rejection control (ADRC) paradigm is proposed for the ALSTOM gasifier control problem. In the new control method, the disturbances, ...including unknown dynamics and external disturbances to the system, are treated as an augmented state that is estimated and then eliminated in real-time. A first-order ADRC scheme for the ALSTOM gasifier is designed. The simulation results show that the new control method is superior to the PI solution by Simm and Xue in terms of the integral of the absolute error of gas pressure disturbance tests at 0% load, the no-overshoot peak value of the gas temperature and the short time for the bed mass to return to the set point during a ramping test, and the ability to reject large coal quality disturbances.
In this study, we used the thermoeconomic theory to evaluate the impact of residue cost formation on the cost of electricity generated from natural gas burned in a gas turbine that applied sequential ...combustion; we also analyzed the impact of the combustion process on the additional fuel consumption to compensate for a malfunction component. We used the Alstom GT24 gas turbine, which applied sequential combustion and generated 235 MW of power. Thermoeconomic analysis indicated that the exergy cost of power generation was 626.33 MW (30.42% corresponded to irreversibility costs, and 29.22% and 2.84% corresponded to the formation costs of physical and chemical residues, respectively). The exergoeconomic production cost of gas turbine was 10,098.71 USD/h, 34.76% from external resources and 65.24% from capital and operating costs. Thermoeconomic diagnosis revealed that a compressor deterioration (of 1-% drop in the isentropic efficiency) resulted in an additional fuel consumption of 4.05 MW to compensate for an increase in irreversibilities (1.97 MW) and residues (2.08 MW); the compressor generated the highest cost (49.9% of additional requirement). Thus, our study can identify the origin of anomalies in a gas-turbine system and explain their effects on the rest of the components.
The combined-cycle power plant is the effective way to increase power and thermal efficiency which can rise thermal efficiency up to 50% corresponding to low heat value of the fuel (LHV). This study ...focused on converting Zubair Oil Field Gas turbine (ALSTOM GT13E2) from single cycle into a combined cycle power plant. Models suggestion design have been presented with back-pressure steam turbine by Cycle-Tempo (5.1) thermodynamics simulation program, which presents value diagram and exergy flow diagram both are useful to understanding the thermodynamic performance of complicated systems.The result of exergy analysis explicate that huge amount of exergy loss firstly occurs in gas turbine combustor (about 60% due to high irreversibility), and heat recovery steam generation (HRSG) is the second major exergy loss in combined cycle power plant (about 30%) recently apparatus concepts less than 10% of exergy (like compressors and expanders). Also, in this study explained the effect of changing the ambient temperature on the performance of power plant by using four temperature parameters on the four simulation models at constant compression ratio. The results were the increase in gas turbine temperature inlet led to decrease the net power output of the CCPPs. Thermal and exergy efficiencies increase when ambient temperature increase due to growth turbine inlet temperature but this temperature restricted by creep rupture and thermal fatigue for combustor parts and turbine blades metal. Maximum thermal and exergy efficiencies can be reached to 55.74, 53.28% respectively at worst ambient temperature. The calculation results in this study were compared with two previous studies, with considerable differences in input parameters of the gas turbine and steam turbine also, the types of the gas turbine models. finally, the results showed acceptable agreement.
This project investigates the energy cost of CO2 capture for NGCC (natural gas combined cycle) power plants and studies the effect of solar thermal energy on the energy penalty for such a system.
The ...gas turbine used in this study is the ALSTOM GT26. Alongside the standard case, other cases include an EGR (exhaust gas recirculation) and a pre-combustion case that utilises EGR with the capture taking place after the compression stage of the gas turbine. The solar thermal technology used in these simulations is a solar tower system capable of reaching 1000 °C. The integration of the solar energy is used to provide heat to the first of the two combustion chambers in the gas turbine. Cases are optimized for 75% capture.
For a NGCC it was found that using EGR decreased the specific energy penalty as well as capture energy penalty. The pre-combustion case showed a reduction in the energy penalty over the standard and EGR cases but at a reduced capture rate. The addition of solar thermal shows a reduction in the total energy penalty. This is due to a reduction in the total CO2 produced in the system, hence a reduction in the total CO2 captured.
•EGR (exhaust gas recirculation) can be used to reduce the specific energy penalty of the NGCC (natural gas combined cycle) power plant.•Compressed gas to capture in the pre-combustion case reduces the energy penalty.•Solar thermal reduces total energy penalty, increases specific energy penalty.•Solar thermal and EGR leads to comparable reboiler duties compared EGR base case.
•The performance of Alstom gasifier for coal quality variations is investigated.•The baseline controller is tuned by Multi objective Particle Swarm Optimisation algorithm.•TOPSIS algorithm chooses ...the best dominant values as controller constants.•The designed controller meets the performance requirements at 0%, 50% and 100% loads.•This paper provides best results for coal quality variations in comparison with recent proposals.
Coal gasifier, an essential part of Integrated Gasification Combined Cycle (IGCC) converts coal into synthesis gas (syngas or producer gas) under certain pressure and temperature. The quality of syngas is highly influenced by quality of coal (calorific value) and hence greatly affects the power generation. Gasifier control seems to be highly difficult since it involves many variables and inherent nonlinearity. The baseline PI controller provided with ALSTOM benchmark challenge II (benchmark model of coal gasifier) fails to satisfy the constraints at 0% load for sinusoidal pressure disturbance and coal quality variations (±18%). This paper evaluates the tuning parameters of ALSTOM benchmark challenge II using Multi-Objective Particle Swarm Optimisation (MOPSO) algorithm. Robustness of the optimal PI controller is tested under sinusoidal and step pressure disturbance tests at 100%, 50% and 0% load conditions with decreased and increased coal quality variations. Test results show that the optimal PI controller meets all the constraints comfortably at all load conditions and provides better results for coal quality variations.
According to the latest IEA report, Carbon Capture and Storage (CCS) from fossil fuel fired power plants is a key option to mitigate CO2 emissions in the 450 scenario. In addition it is the only ...technology capable of large CO2 emission reduction from industrial applications and in combination with biomass firing the only currently available technology for reducing CO2 concentration in the atmosphere by means of negative emission performance. Alstom develops CCS technologies for post- combustion and oxy-combustion, and have shown that these technologies can compete with renewable power generation on the basis of Levelized Cost of Electricity (LCoE). It is now essential that governments give the same priority to CCS as to renewables in order for large demonstration plants to be built, a necessary step in the development of the technology. The Norwegian Government, through its special purpose company Gassnova, is at the forefront of making this happen by construction of the world's largest test site for Carbon Capture. The Technology Center Mongstad (TCM) is owned by Gassnova, Statoil, Shell and Sasol. The unique location of TCM, next to the Mongstad refinery, provides interesting opportunities in terms of gases to be treated. The plant at TCM is designed to treat both refinery off-gas from a cracker operation as well as the exhaust from a gas turbine based combined heat and power plant. In addition, the captured CO2 can be recycled to achieve any CO2 concentration between 4 and 13% by volume. The Alstom Chilled Ammonia Process (CAP) is post-combustion technology that captures CO2 emitted from power plants or industrial sources. Deployment of this technology requires operating data and validated simulation tool for design that can evaluate various CAP configurations to achieve the lowest possible capital cost, energy demand and operating cost. A special focus will be directed to the CAP Installation at TCM, which was commissioned in 2012. The plant is designed to treat both refinery off-gas from a cracker operation as well as the exhaust from a gas turbine based combined heat and power plant.
This paper will report on the first results of Chilled Ammonia Process (CAP) as part of Alstom's development program of commercial solution for carbon capture, at Technology Center Mongstad in 2012.
Alstom Power and The Dow Chemical Company have jointly developed an Advanced Amine Process (AAP) utilizing Dow's advanced amine solvent formulation UCARSOL™ FGC-3000 for the capture of CO2 from ...fossil fuel power plant-generated flue gas. This development effort includes the use of facilities to address operational issues such as energy efficiency and solvent management, along with environmental factors such as emissions and wastes. A new demonstration facility has been constructed in Le Havre, France, through a partnership between Alstom and Électricité de France (EDF) with support from ADEME, the French Environment and Energy Management Agency. This facility is designed to capture 25 tonnes of CO2/day at a 90% capture rate on a slip- stream flue gas from a hard coal-fired power plant.
The EDF-Le Havre demonstration plant is equipped with flue gas conditioning for controlling the water content, temperature and SOx level of the incoming flue gas stream. The CO2 absorber column contains structured packing selected for optimal CO2 capture efficiency and fluid flow characteristics. The exiting flue gas passes through a water wash section designed to capture residual amine emissions. Amine solvent management comprises an amine reclamation system and assisted by an on-site amine solvent analytical laboratory.
The quality of the incoming flue gas, the exiting flue gas and CO2 product gas streams are assessed through various gas sample locations in the pilot plant. Amine solvent sampling is available at various locations throughout the amine circulation loop as well as the liquid discharge locations for waste assessment. Additionally, the EDF facility is also equipped with an oxygen stripper to study the impact on solvent degradation.
The current status of the Alstom Advanced Amine Process at EDF will be discussed in this paper. The presented results include the performance of the UCARSOL™ FGC-3000 amine solvent evaluated under varied process conditions in an advanced flow scheme set-up. The test campaign comprised several series of tests, including energy consumption at varied liquid-to-gas flow ratios (L/G) in the absorber while maintaining 90% CO2 removal, the effect of varying process conditions at a set solvent circulation rate, and the effect of different absorber intercooling and recirculation configurations on energy consumption. Results show that the advanced flow scheme effectively reduced power and energy demand by over 30% at a 90% CO2 capture rate versus a conventional process scheme with MEA solvent.
We address the issue of the relevance in the transnational arena of the concept of patriotic vigilance, as expressed by French Minister Arnaud Montebourg in 2014. Firstly, we examine the ...globalization paradox with its underpinnings in the literature and its illustration through the recent Alstom saga. Secondly, we review the idea of a paradigm shift in world monetary affairs signaled by the recent crisis. Finally, drawing on Kant’s ideas on cosmopolitism, we sketch out an alternative to the globalization paradox.
Decentralized integral controllability (DIC) is an important property of industrial and process multivariable control systems. In this paper, some of the previously proposed conditions for the study ...of the DIC of certain systems are extended to treat systems with correlated and independent uncertainty. These conditions are based on the concept of the stability of Polytopic and Interval family of matrices, and evaluation of the Lyapunov condition only at special vertices of these families. By comparison with previous sufficient conditions, and known necessary conditions, it is demonstrated that the newly proposed criteria are significantly less conservative, especially in the case of correlated uncertainties.
► We study integrity of uncertain systems with integral action decentralized control. ► The Decentralized Integral Controllability condition is studied. ► The conditions consider both independent and correlated uncertainties. ► The conditions are less conservative that previously proposed conditions.
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