Gas Turbine Power Generation System Research Articles

A Novel Day-Ahead Optimization-Oriented Low-Carbon Economic Scheduling Scheme for Integrated Energy Systems

As the global energy structure undergoes transformation and the low-carbon development process continues to advance, integrated energy systems have progressively emerged as crucial technical support for achieving sustainable development. In this paper, a joint-day optimal scheduling model is put forward considering the existence of dispatchable resources in community integrated energy systems (CIES). The aim is to cut down the system operation cost and enhance energy utilization efficiency. This model is founded on the concept of energy hubs and combines the shiftable, transferable, and reducible characteristics of demand-side flexible loads. It includes gas turbine power generation systems, energy storage, as well as wind and solar renewable resources. System operation cost and carbon trading cost are comprehensively taken into account, and ultimately, the CIES low-carbon economic dispatch model with the lowest total cost as the optimization objective is established. The Yalmip toolbox and Cplex solver are employed to solve the model. The optimization results of flexible electric and thermal loads participating in dispatching under different scenarios are analyzed through simulation. The economic benefits of electric and thermal independent dispatching are compared and analyzed, and the economic benefits of electric and thermal coupled dispatching are verified. The study reveals that the rational scheduling of user-side flexible loads can notably reduce operating costs, lower the load peak-to-valley difference and carbon emissions, and boost the comprehensive economic and environmental benefits of the system.

Research on Low Concentration Gas Catalytic Oxidation Power Generation System

In response to the difficulties in direct utilization of low concentration gas in coal mines and the slow development of industrial application of catalytic oxidation technology, a new mode of direct utilization of low concentration gas with a methane concentration of 1.0% in coal mines in catalytic oxidation gas turbine power generation is explored. And based on the development of a 30kW low concentration gas catalytic oxidation gas turbine power generation system, this paper introduces the design process of key equipment such as catalytic oxidation burners, low-temperature and low-pressure turbines, and countercurrent regenerators, providing a technical reference for the utilization of low concentration gas catalytic oxidation.

Economic analysis of gas turbine/supercritical carbon dioxide combined cycle under different cycle configurations

S–CO2 cycle systems have many advantages, but coupling with gas turbine power generation systems has been poorly studied. Considering the huge cold energy of LNG, it can not only be used as coolant in combined cycle system, but also the natural gas after heat exchange can be used as fuel input for combined cycle and the remaining part can be supplied to city users. In this paper, ten combined cycles were proposed for both water and LNG media, with/without intercooling process and the number of flue gas heat exchangers. A detailed analysis of the investment cost, operating income and payback period of the cycle power system is carried out by selecting the appropriate cost equation. The results show that increasing the number of flue gas heat exchangers, increasing the number of coolers and using LNG as the cooling medium can improve the energy efficiency. Cascade 9 (GT/two flue gas heat exchangers intercooled LNG tandem combined cycle system) has a maximum annual benefit of 19.59 (106$); a maximum cumulative benefit (20 years) of 204.78 (106$) for Cascade 9; Cascade 9 (GT/two flue gas heat exchangers intercooled LNG tandem combined cycle system) has a minimum payback period of 7.81 years.

Hybrid energy storage power allocation strategy based on parameter-optimized VMD algorithm for marine micro gas turbine power system

The power system onboard ships is typically a low-inertia, small-capacity isolated grid that is highly susceptible to system disturbances and instability, especially when connected to high power pulse loads. To mitigate power fluctuations and ensure stable operation, a hybrid energy storage system (HESS), which comprises the battery system and flywheel energy storage devices, has emerged as a promising solution. This paper explores the control strategy and coordinated operation of marine gas turbine power generation systems operating under pulse load conditions and presents a novel hybrid energy storage power allocation strategy based on variational mode decomposition (VMD). Specifically, we propose to implement parameter optimization of VMD using an artificial hummingbird algorithm (AHA), which enables effective primary allocation of hybrid energy storage power. To achieve secondary power allocation, we design two fuzzy controllers to optimize the state of charge (SOC) of battery system and speed of flywheel device. To evaluate the feasibility and effectiveness of the proposed control strategy, we establish a theoretical model of a shipboard micro gas turbine (MGT) direct current (DC) power system, which includes an MGT, generator, HESS, and pulse power load. Our simulation results demonstrate that the artificial hummingbird algorithm outperforms the particle swarm algorithm concerning search speed and calculation accuracy for parameter optimization of variational mode decomposition. Moreover, the proposed parameter-optimized VMD method can adaptively decompose pulse load power fluctuations and achieve optimal allocation of the flywheel and battery power in the HESS. Finally, the parallel fuzzy controller design effectively optimizes the operation ranges of the flywheel device and battery system, prevents over-charging and over-discharging of energy storage equipment, ensures that the SOC of energy storage equipment remains within a fixed interval, and reduces frequent and high-power charging and discharging of batteries.

Mitigation effect of flywheel energy storage on the performance of marine gas turbine DC microgrid under high-power load mutation

Due to the slow response of output power of the traditional marine micro gas turbine, the directly connecting of high-power load to a shipboard micro gas turbine power generation system usually causes large power imbalance and instability instantly. To address this issue, a flywheel energy storage system (FESS) is applied to compensate the transient power changes, mitigate load fluctuations and maintain the voltage of the shipboard direct current (DC) bus. Based on a practical 100 kW micro gas turbine generator set, a detailed model of DC microgrid for the micro gas turbine generation system including micro gas turbine, FESS, synchronous generator, excitation system and load is established. The coordinated control strategy of micro gas turbine, FESS and load system is designed. The mitigation effects of FESS on marine gas turbine DC microgrid under high-power load mutation are explored by performing simulation with sudden load changes of 25%, 50% and 75% rated power and comparing the performance with and without FESS. The effectiveness of the control strategy has been verified by simulation analysis. The simulation results show that by reasonably designing the coordinated control strategy, the fluctuation of the power system can be effectively mitigated when sudden load, especially high-power sudden load is considered. The stability of the marine gas turbine microgrid has been greatly improved.

Feasibility of Hybrid Desalination Plants Coupled with Small Gas Turbine CHP Systems

Nowadays, several technologies for desalination processes are available and widely employed. However, they consume a considerable amount of energy and involve high capital and operating costs. Therefore, the techno-economic analysis of a system coupling different energy sources with the desalination processes is of value. The possibility of coupling a small gas turbine combined heat and power system (GT CHP) with hybrid desalination plants (HDPs) has been assessed in this study. The proposed gas turbine power generation system, based on a single-stage centrifugal compressor and an uncooled centripetal turbine, provides design simplicity and reasonable installation costs for the power generating plant. The hybrid desalination technique, based on the use of two different desalination technologies, i.e., Reverse Osmosis (RO) and a thermal desalination process, has been chosen to better exploit the electrical and thermal energy produced by the mini CHP plant. The proposed solution is numerically investigated from both thermodynamic and economic points of view, and the results of the thermodynamic analysis of the cycle are used as input for the evaluation of the amount of freshwater produced and of costs. The economic assessment of standalone desalination systems is also shown for the comparison with the hybrid solutions here proposed. Results show that the total cost of the water produced by MED + RO was less than the total cost of the water obtained by MSF + RO, and that the energy cost of MED + RO hybrid desalination system was about 15% less than that for stand-alone RO desalination technology. Thus, the MED + RO hybrid desalination system can be considered a promising solution for the coupling with the proposed mini GT CHP plant, which, due to the small size and cost, as well as the easy installation, can be easily applied in off-grid or remote areas.

Thermodynamic Assessment of Membrane-Assisted Premixed and Non-Premixed Oxy-Fuel Combustion Power Cycles

Abstract This study focuses on the investigations of gas turbine power generation system that works on oxy-combustion technology utilizing membrane-assisted oxygen separation. The two investigated systems are (i) a premixed oxy-combustion power generation cycle utilizing an ion transport membrane (ITM)-based air separation unit (ASU) which selectively allows oxygen to permeate from the feeding air and (ii) a non-premixed oxy-fuel combustion power cycle, where oxygen separation takes place, with cogeneration of hydrogen in an integrated combustor. A gas turbine combined cycle that works on conventional air–methane combustion was considered as the base case for this work. Commercial software package Hysys V8 was utilized to conduct the process simulation for the proposed cycles. The two novel cycle designs were proposed and evaluated in comparison with that of the conventional cycle. The first law efficiency of the premixed combustion power cycle was calculated to be 45.9%, a loss of 2.4% as an energy penalty for the oxygen separation. The non-premixed cycle had the lowest first law efficiency of 39.6%, which was 8.7% lower than the efficiency of the base cycle. The lower effectiveness of the cycle could be attributed to the highly endothermic H2O splitting reaction for oxygen production. High irreversibility in the H2O-splitter and the reactor was identified as the main cause of exergy losses. The overall second law efficiency of the non-premixed power cycle was around 50% lesser than that of the other cycles. The energy penalty related to air separation is dominated as the parameter that reduces the efficiencies of the oxy-fuel combustion cycles; however, the premixed combustion cycle performance was found to be comparable to that of the conventional air-combustion cycle.

Operating scenario of 3GWth class FFHR power plant with bypass controlled supercritical CO2 gas turbine power generation system

Abstract In order to achieve high power generation efficiency, facility compactness, high safety, and high coexistence with fuel tritium in the 3 G Wth class FFHR(Force Free Helical Reactor) power plant, optimization, performance and operation scenario of the power generation system of the power plant model using the axial flow type uniaxial supercritical CO2 gas turbine power generation system were examined. As a result, the following conclusions were obtained. (1) The most efficient and compact axial flow uniaxial design supercritical CO2 gas turbine power generation system suitable for 3 G WthFFHR power plant has a maximum heat capacity of 1.5GWth×2, and the gas turbine conversion rate at that time was evaluated as 46.9 %(= 1,267MWe/2,700MWth). Therefore, split connection with two power generation systems is optimal for a 3 G Wth class FFHR power plant. Here, the operating speed of the turbo equipment was set to 3600 rpm in order to adapt this plant model to the power supply system in Japan. (2) Simultaneous supply of 818MWe/300 s electricity and 300MWth/30days heat is required at startup of the FFHR. (3) The in-house power during steady operation under the self-ignition condition was reduced to about 31.7MWe, and the amount of power generated at the transmission end was evaluated as 1,234MWe.

Effects of thermophysical and thermochemical recuperation on the performance of combined gas turbine and organic rankine cycle power generation system: Thermoeconomic comparison and multi-objective optimization

In this paper, effects on the performance of a combined gas turbine and organic Rankine cycle (GT/ORC) system of using thermophysical and thermochemical recuperation based on methane steam reforming (MSR) process is investigated from the viewpoint of thermoeconomics. For this purpose, three power generation systems consisting of simple GT/ORC, GT/ORC with thermophysical recuperators (TPR) and GT/ORC with thermophysical and thermochemical recuperators (TPCR) are proposed and compared thermodynamically and economically. In addition, the multi-objective optimization using genetic algorithm is conducted for the systems and the systems characteristics at the final optimum design points are compared. Resultsreveals that the thermodynamic, economic and environmental performance of all three proposed power generation systems are enhanced as the combustion temperature raises. In addition, the power generation system with TPR shows the best performance from the thermodynamic perspective with the 22.86% and 27.52% improvement in the exergy efficiency compared to the simple GT/ORC and GT/ORC with TPCR, respectively. However, under the operating thermodynamic conations obtained by the multi-objective optimization approach, the product cost associated with the system using TPCR is less than that of the other configurations.

Progress in Modeling and Control of Gas Turbine Power Generation Systems: A Survey

This paper reviews the modeling techniques and control strategies applied to gas turbine power generation plants. Recent modeling philosophies are discussed and the state-of-the-art feasible strategies for control are shown. Research conducted in the field of modeling, simulation, and control of gas turbine power plants has led to notable advancements in gas turbines’ operation and energy efficiency. Tracking recent achievements and trends that have been made is essential for further development and future research. A comprehensive survey is presented here that covers the outdated attempts toward the up-to-date techniques with emphasis on different issues and turbines’ characteristics. Critical review of the various published methodologies is very useful in showing the importance of this research area in practical and technical terms. The different modeling approaches are classified and each category is individually investigated by reviewing a considerable number of research articles. Then, the main features of each category or approach is reported. The modern multi-variable control strategies that have been published for gas turbines are also reviewed. Moreover, future trends are proposed as recommendations for planned research.

Design and analysis of renewable hydrogen production from biogas by integrating a gas turbine system and a solid oxide steam electrolyzer

In this paper, design and performance analysis of a biogas (60%CH4 + 40%CO2) fueled gas turbine (GT) power generation system integrated with a flameless boiler for steam generation for hydrogen production in a solid oxide steam electrolyzer (SOSE) is reported. In this design, the exhaust gases from GT is conducted to a flameless boiler where diluted and preheated exhaust gases are employed as an oxidizer in this process. Using a small amount of biogas in the flameless boiler enables the hybrid system to produce required steam for SOSE process and the whole generated electrical power by GT is employed in SOSE as well to produce hydrogen. The effects of biogas blends and flowrate, turbine inlet temperature (TIT), steam temperature and the electrode characteristics on the performance of the hybrid system are evaluated. The results indicate that by purification of biogas and increasing CH4 concentration up to 80%, the generated electrical power and produced hydrogen of the hybrid system augment 24% and 20% respectively. In GT system, the TIT should be set at the temperatures higher than 1300 K to prepare a desirable circumstance for the operation of flameless mode in the boiler. At the constant electrical power, when steam temperature increases, the overall SOSE potential decreases and consequently the current of the SOSE enhances which result in the enhancement of the overall hydrogen production in high steam temperatures. To increase the steam temperature from 850 K to 1450 K, the rate of overall biogas consumption of the system increases 1% while the amount of overall hydrogen production from SOSE system augments from 0.01 to 0.052 mol/s. The presented analysis in this paper can be employed to perform more analyses to achieve insightful understanding of the green hydrogen production using hybrid systems.

Comparative Study Between Three Modeling Approaches for a Gas Turbine Power Generation System

This paper presents a comparison between three modeling approaches for a gas turbine power generation system. These approaches involve artificial neural network (ANN), state space subspace and physical-based methods. The purpose is to compare the adopted methods in terms of modeling, simulations and control systems feasibility. It is proved that ANN is the most accurate methodology in reflecting constant outputs and large variation trends as the ANN is found to be able to capture the severe nonlinearity of the process easily. However, the state space is found be more feasible than other techniques for control system stability studies and applicability of control system algorithms in addition to best simulating small variation trends of the output, such as frequency excursions and temperature variations. The method used for state space system identification is based on the standard realization theory of controllability and observability matrices with the use of singular value decomposition technique to compute the system parameters. The superiority of the physical-based model is the acquisition of the physical insight necessary to study the system abnormalities, such as transient stability studies of the generator, and keeping better performance for simulating small trends or excursions even in the verification phase. The physical laws are rooted from thermodynamic relations, torque balance equation that governs the turbine-generator interactions, and the two-axis relations of the rotor and stator dynamics, and the physical model parameters were identified using genetic algorithm. The comparison that justifies the diversity in the capabilities of the models has been reported for guidance in future research.

Performance Assessment and Economic Analysis of a Gas-Fueled Islanded Microgrid—A Malaysian Case Study

In this study, the performance of an islanded gas turbine power generation system in Malaysia was investigated. Considering the low fuel efficiency of the plant during peak and part-load operations, an economic analysis was also carried out, over the period of one year (2017). The case study was conducted on the isolated electrical network of the Universiti Teknologi PETRONAS (UTP), which consists of two gas turbine units with a total capacity of 8.4 MW. Simple performance indicators were developed to assess the performance, which can also be applied to other power stations in Malaysia and elsewhere. Meanwhile, the economy of variable load operations was analyzed using the statistical data of generation, fuel consumption, and loads. The study reveals that the capacity factor of the microgrid in the period was between 52.77–63.32%, as compared to the industrial best practice of 80%. The average plant use factor for the period under review was 75.04%, with a minimum of 70.93% and a maximum of 78.61%. The load factor of the microgrid ranged from 56.68–65.47%, as compared to the international best practice of 80%, while the utilization factor was between 44.22–67.655%. This study further reveals that high fuel consumption rates, due to the peak and part-load operations, resulted in a revenue loss of approximately 17,379.793 USD per year. Based on the present performance of the microgrid, suggestions are made for the improvement of the overall performance and profitability of the system. This work can be valuable for microgrid utility research to identify the most economical operating conditions.

Using inlet guide vane to improve load following ability of solid oxide fuel cell and gas turbine hybrid cycle

High efficiency and high reliability with low emission of solid oxide fuel cell make them one of the best choices for distributed generation systems. Furthermore, the gas turbine power generation systems are completely developed in recent decades. Hybrid cycle of SOFC and gas turbine gathers these points and introduces the highest possible efficient system for building heating and power. The behavior of this cycle can be studied from a model of fuel cell, gas turbine and balance of plant. For each component a model is developed and the performance of the overall system analyzed by integrating each model. Load variation for SOFC-GT hybrid cycle in residential application is very wide. To adjust the net power and choosing best operation point for SOFC-GT hybrid cycle, an inlet guide vane (IGV) is used in the inlet of the compressor. In this study by using a dynamic model, transient effect of IGV angle on performance of SOFC-GT hybrid cycle is investigated. Also this model can be used for designing a controller for safe operation of this cycle while satisfying constraints of the hybrid cycle. Results showed that by using IGV, the off-design performance of the SOFC-GT cycle is enhanced.

Cooperative controls of micro gas turbine and super capacitor hybrid power generation system for pulsed power load

Due to slow response of conventional micro gas turbine(MGT) generator system, pulse power load(PPL) will cause large voltage sags and overshoot of direct current(DC) bus voltage, and even lead to instability. In this paper, super capacitor(SC) energy storage system(ESS) is applied to MGT to form a hybrid power generation system. Then the two cooperative control methods of hybrid generation system are proposed. One is the PI-based control algorithm, and the other is the fast power coordinated control method through MGT output power forecast. The fast power dynamic response of SC ESS can compensate for low dynamic response of MGT, which makes the hybrid generation system in equilibrium state of transient power in real time. Voltage of DC bus is smooth, and adaptability of MGT to PPL is enhanced. The second control algorithm is proposed according to power output characteristics of MGT, and has the advantages of fast and balanced power distribution. The algorithm of fast charging and exiting of SC ESS is proposed based on load conditions, and the charging process will not cause any impact. Finally, simulation model is established to verify the effectiveness of the two control algorithms, and the results are compared.

Use of hot supercritical CO2 produced from a geothermal reservoir to generate electric power in a gas turbine power generation system

CO2 capture and sequestration in deep saline aquifers is widely considered to be a leading option for controlling greenhouse gas emissions. One such possibility involves injection of supercritical carbon dioxide into a high-permeability geothermal reservoir. In addition to the benefit of sequestering the CO2 in the reservoir, the CO2 can be used to mine geothermal heat for utilization above ground. This paper describes one of the options for generating power from hot supercritical CO2 obtained from CO2 production wells connected to a geothermal reservoir, where the original source of the CO2 is CO2 captured from fossil-fired power plants or industrial processes. The cost of power generated using CO2 produced from a geothermal reservoir with a gas turbine generation system is compared to the cost of generating power from a conventional geothermal steam power plant.

A systematic approach to find the best road map for enhancement of a power plant with dew point inlet air pre-cooling of the air compressor

Dimensional characteristics and operating parameters of the optimized Maisotsenko indirect evaporative cooler for pre-cooling of the compressor’s inlet air and consequently enhancement of the gas-turbine power generation system as well as the best investment strategy for it were found for an in-operation combined cycle power plant through a systematic approach. Four optimization scenarios were proposed considering different combinations of annual average of net power of the gas-turbine power generation system, payback period time and enthalpy difference of exhaust gases compared to the reference state of each gas-turbine power generation system as objective functions. In each scenario, optimization was conducted for different possible percentages of investment allocated to the research and development of the project. After that, analytical hierarchy process was used to find the best percentage of investment allocated to the research and development of the project of each scenario and the final selected one. Having introduced the approach, it was implemented for Montazer-Ghaem combined cycle power plant in Iran. The results showed for that case study, the analytical hierarchy process selected an optimization scenario in which the annual average of the net power and the enthalpy difference of the exhaust gases compared to the reference state were the objective functions and 15% of the total profit of the gas-turbine power generation system sold electricity was dedicated to the improvement project. This optimization had the payback period time of 2.67years and it also improved the annual average of the net power of gas-turbine power generation system and enthalpy difference of the exhaust gases compared to the reference state 6.02 and 8.92%, respectively.

Grey Prediction Control for Gas Turbine Power Generation System

With the rapid development of CCHP, the construction of Energy Internet, the mature mining technology for natural gas and the improvement of P2G technology, the proportion of gas turbine units for generating electricity is higher and higher. As the energy conversion hub of gas and electricity, the stability of gas turbine is of great significance to the safe, economical and reliable operation of power system. In order to improve its stability, this paper applied grey prediction to its speed control system, and a simulation model for gas turbine power generation system in the mode of island operation was built on the Matlab/Simulink. The simulation results have shown that grey prediction can reduce the overshoot and accelerate the response speed of the system under both the small and large disturbance, and it can enhance the robustness of gas turbine and improve the stability of gas turbine power generation system effectively.

Power balance control of micro gas turbine generation system based on supercapacitor energy storage

In view of the impact load problems in the traditional micro gas turbine (MT) power generation system, this paper analyzes its working mechanism and finds the reason lies in the slow response of the micro turbine output power adjustment. In order to make up for the shortage of the instantaneous output power of micro turbine, the method of instantaneous power fast control is proposed. Control algorithm of instantaneous compensation power is raised by power response prediction of MT. The high power dynamic response of super-capacitor energy storage can compensate low dynamic response problem of MT output power, so the instantaneous power of the system is real balance to ensure that the DC bus voltage is smooth and adaptability of MT power generation system is enhanced for impact load. Finally, the correctness and feasibility of the proposed control strategy are verified by simulation results.

Performances and emission characteristics of NH3–air and NH3[sbnd]CH4–air combustion gas-turbine power generations

For the first time, NH3–air combustion power generation has been successfully realized using a 50kW class micro gas turbine system at the National Institute of Advanced Industrial Science and Technology (AIST), Japan. Based on the global demand for carbon-free power generation as well as recent advances involving gas-turbine technologies, such as heat-regenerative cycles, rapid fuel mixing using strong swirling flows, and NOx reduction using selective catalytic reduction (SCR), allow us to realize NH3–air combustion gas-turbine system, which was abandoned in the 1960′s. In the present system, the combustor adopted gaseous NH3 fuel and diffusion combustion to enhance flame stability. The NH3 pre-cracking apparatus for combustion enhancement using generated H2 was not employed. The NH3–air combustion gas-turbine power generation system can be operated over a wide range of power and rotational speeds, i.e., 18.4kW to 44.4kW and 70,000rpm to 80,000rpm, respectively. The combustion efficiency of the NH3–air gas turbine ranged from 89% to 96% at 80,000rpm. The emission of NO and unburnt NH3 depends on the combustor inlet temperature. Emission data indicates that there are NH3 fuel-rich and fuel-lean regions in the primary combustion zone. It is presumed that unburnt NH3 is released from the fuel-rich region, while NO is released from the fuel-lean region. When diluted air enters the secondary combustion zone, unburnt NH3 is expected to react with NO through selective non-catalytic reduction (SNCR). NH3CH4–air combustion operation tests were also performed and the results show that the increase of the NH3 fuel ratio significantly increases the NO emission, whereas it decreases the NO conversion ratio. To achieve low NOx combustion in NH3–air combustion gas turbines, it is suggested to burn large quantities of NH3 fuel and produce both rich and lean fuel mixtures in the primary combustion zone.