A regional integrated energy system based on solar, geothermal and natural gas is constructed to meet the multi-load demands of buildings, electric vehicles and hydrogen fuel vehicles. Hydrogen storage tank and heat storage tank are used to adjust the system flexibility, and to achieve systematic low-carbon economic operation on the basis of meeting the energy demand. Taking the residential community as an example, the distinctions of travel behavior for new energy vehicles on weekday and weekend are investigated, the change of travel frequency with different seasons are also considered, and the yearly loads of residential and new energy vehicles are determined. Primary energy saving rate, CO₂ emission reduction ratio and total annual expenditure reduction ratio of the proposed system are set as optimization objectives, and the capacity configuration of integrated system is optimized based on the mixed integer linear programming so as to evaluate the system performances from the aspects of economy, energy and environment. The results show that, primary energy saving rate, CO₂ emission reduction ratio, total annual expenditure reduction ratio and total investment income of the optimized system are 42.95%, 55.89%, 50.82% and 49.18%. In the integrated system, the input power of public grid only accounts for 16.93% of the total power load. This study provides theoretical basis for the integration of novel energy supply system considering coupling loads of residential building and new energy vehicles, which is helpful to promote the application of integrated energy system in building and transportation areas.

In order to understand the performance changes and potential risks of hydrogen assisted combustion in combustion chamber of a lean-combustion premixed gas turbine, a numerical simulation study of the hydrogen injection combustion process of natural gas was carried out in the combustion chamber of Siemens SGT-800 gas turbine. The fuel ignition, temperature distribution, flame formation and NO_x emission characteristics of the combustion chamber under five working conditions of 0, 5%, 10%, 15% and 30% were investigated. Studies have shown that hydrogen-doped combustion in the current combustion chamber will lead to an earlier ignition position of the fuel, an increase in temperature peaks, a shorter axial length of the flame, and a gradual convergence of the outer duty flame towards the central mixer. The temperature distribution and flame morphology in the combustion chamber will not change significantly when the hydrogen-doped ratio is below 15%, but the ignition position in the mixer tube is seriously retracted at 30% hydrogen-doped ratio, and the flame on the outside is close to the nozzle outlet, which has a risk of tempering. In addition, the NO_x emission value of the combustion chamber outlet increases with the hydrogen doping ratio, and the NO_x emission value exceeds the standard by nearly 1/3 at 30% hydrogen doping ratio, indicating that high NO_x emission is also one of the factors restricting the high proportion of hydrogen doping in gas turbines.

In order to improve thermal efficiency of the solar cavity particle receiver, this paper designs the quartz spiral tube solar cavity particle receiver with quartz spiral tube, and establishes flow model to conduct comparative analysis on the structural parameters of the receiver. Finally, the cone angle of the cavity is set to 5°, the number of spiral turns is set to 5, and quartz window is adopted. In order to analyze the heat transfer characteristics of this receiver, this paper studied the influence of different incident radiation intensities and particle mass flow on it. The results show that, within the range of incident radiation intensity of 100 000 W/m² to 350 000 W/m² and particle mass flow of 0.002 kg/s to 0.051 kg/s, the highest particle temperature at the outlet is 672 ℃, and the highest efficiency of the receiver is 70.12%. The research has reference significance for the design of high-temperature solar particle receivers.

The dynamic characteristics of the bottoming cycle of a gas turbine combined cycle have a significant influence on the load variation characteristics of the unit. Partially recuperation is a new method which can be used to improve the performance of combined cycle at partial load, it is an important part of system feasibility evaluation to study the effect of partially recuperation on the dynamic characteristics of the bottoming cycle. In this paper, a dynamic simulation model of the bottoming cycle system of a partially recuperative combined cycle unit is established by using modular modeling method, and the dynamic characteristics of inlet parameter disturbance and load shedding process are studied. The results show that, the dynamic model can accurately reflect the dynamic characteristics of the bottoming cycle, and the simulation results show that the dynamic response of partially recuperative units facing the disturbance of exhaust parameters is consistent with that of conventional units. The disturbance of exhaust temperature T₄ mainly affects the high-pressure superheated steam and reheated steam, and the influence range is larger. The disturbance of T₄ with 5% can reduce the bottoming cycle power by 16.32%. The response speed of the unit is slower, and the time constant of the steam turbine power is about 400. The disturbance of exhaust flow affects the steam of each stage, and the influence range is relatively small, the disturbance of 10% reduces the bottoming cycle power by 9.49%, the response speed of the unit is faster, the time constant of the steam turbine power is about 60. When the recuperative ratio is disturbed, the dynamic response of the unit is similar to that of the T₄ disturbance, and the operation strategy of recuperative regulation results in the load variation of the combined cycle being borne entirely by the bottoming cycle, the time needed for partially recuperative units to reach steady state is 1 100 s later than that of conventional units, and the recuperative regulation mode is suitable for use in the load interval below 51.4%.

Under partial shading conditions (PSC), the P-U characteristics of a solar photovoltaic array may exhibit multi-peak phenomena. Conventional algorithms tend to fall into local maximum power point (LMPP), while maximum power point tracking (MPPT) methods based on meta heuristic algorithms are difficult to balance speed and accuracy. In this regard, this paper designs a hybrid algorithm based on the improved particle swarm optimization (IPSO) with embedded the improved perturbation and observation (IP&O). The velocity and position of the particle are first updated by the IPSO algorithm. Then, perform MPPT based on the position of particles using the IP&O algorithm. The tracked power is used as the fitness value of the particles, so that IPSO can find the global maximum power point (GMPP) among many LMPPs. Finally, with the global optimal output of IPSO as the initial position, IP&O is used again for global maximum power point tracking (GMPPT). Comparing the proposed algorithm with IP&O, IPSO, and IPSO-P&O through simulation, the simulation results show that the proposed algorithm performs excellently in tracking speed and accuracy, especially in the case of a wide voltage search range, and has smaller power oscillations during the tracking process.

For the analysis of the heat applied to equipment outside the system boundary, the energy utilized was outside the GB/T 10184 standard, and the boiler efficiency calculation could not take advantage of the existing standard. The external heat loss of hot air was divided into two categories: hot air reuse and hot air non-reuse. Based on the GB/T 10184 calculation framework, the calculation methods of these two categories of external heat loss of hot air were proposed. Taking a 350 MW boiler as a practical example, under the same load, continuous operation of hot air external use and shutdown of hot air external use were compared. According to the actual test data and analysis results, the calculation method was used to compare the actual operating conditions. The influence of external loss of hot air on boiler efficiency was analyzed. The results showed that the test results of combustible materials in two working conditions were basically the same. The external loss of hot air in T01 (cold air recovery) was 0.82%, the external loss of hot air (cold air nonrecovery) was 0.13%, and the external loss of hot air in T02 was 0. The measured boiler efficiency in T01 and T02 conditions was 93.10% and 94.00% respectively. The operation of external hot air system reduced the boiler efficiency by about 0.9 percentage point.

The effects of tray parameters on desulfurization efficiency and energy consumption of desulfurization towers are investigated. Through the large-scale hot test platform, the effects of different pore diameters, opening ratio, opening form, weir plate height and different installation positions on desulphurization efficiency and energy consumption are studied. In this paper, the energy consumption efficiency ratio is proposed for the first time as an index to evaluate the operation economy of desulfurization tower. It is found that, under the conditions of experimental platform, when the liquid-gas ratio is not more than 13.6 L/m³, it is economically advantageous to choose sieve plate with medium aperture, high weir board, small opening rate, low-level arrangement, and new aperture design. When the liquid-gas ratio is large than 13.6 L/m³, it is economically advantageous to choose sieve plate with medium aperture, high weir board, large opening rate, high-level arrangement, and new aperture design. The conclusion is of guiding significance for the design and selection of sieve plates for desulfurization and desulfurization towers.

The typical faults of wind turbines are summarized. The fault data and non-fault data of converter system, generator system, variable propeller system and auxiliary power system with high fault frequency of wind turbines in a wind farm are selected for fault diagnosis research. The fault diagnosis model is established by ELM, SVM, KELM and WOA-KELM algorithms respectively. At the same time, Laplacian scores are used to sort and select the importance degree of model characteristic variables. WOA-KELM algorithm achieves better diagnostic effect by optimizing the regularization parameter C and kernel parameter γof KELM algorithm. The results show that, the diagnostic accuracy of the four algorithms for non-fault types is 100% under different sample numbers. The average diagnostic accuracy of WOA-KELM algorithm improves from 88.0% to 93.2% after feature screening by using Laplace scores. In the range of 250~500 samples, the diagnostic accuracy of WOA-KELM algorithm reaches the maximum of 96.0% after feature screening. It is proved that this model can effectively realize the fault diagnosis of wind turbine, and provide guidance and reference for field operation and maintenance personnel.

In order to explore the formation and evolution of soot during the combustion of coal, this paper uses Pingdingshan coal as combustion material, and uses the light scattering method coupled with the thermophoretic sampling article diagnostic method to measure the soot mass in flame. A light scattering measurement system capable of precise vertical movement is constructed to measure the light scattering intensity at different heights of the flame. The particle size distribution is obtained by the thermophoretic sampling particle diagnostic method, and the soot mass at different heights when the flame is calculated by Mie scattering theory. The results show that as the flame rises, the median mass diameter of soot firstly increases and then decreases. When the flame burns stably, a large amount of soot is formed at a height of H=10 mm. As the flame rises, the mass of soot decreases rapidly in the H=10~30 mm range. In the range of 10~20 mm, the soot mass of Pingdingshan coal decreases by 58.62%. When H>40 mm, the soot mass of Pingdingshan coal slowly decreases.

As the global climate continues to warm, capturing carbon dioxide in the air has become one of the most effective measures to reduce greenhouse gas pollution. Carbon dioxide storage systems not only store carbon dioxide in the air, but also consume excess electricity to fill the shortage of electricity supply during peak periods. As the core equipment of CO₂ storage system, the performance of the compressor directly affects the overall performance of the system. This paper summarizes the application scope and performance characteristics of seven different forms of carbon dioxide compressors and the current status of research at home and abroad. The potential problems that may exist in the application of piston, centrifugal and axial flow compressors in CO₂ energy storage systems are discussed, and corresponding suggestions and improvement ideas are given. The results of the study can provide a reference for the design and optimization of CO₂ compressors in the future.