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Metaverse Application in Power Systems AI Introduction
Abstract：Metaverse is a new internet application and social form of virtual reality integration which is produced by integrating a variety of new technologies. With the goal of “carbon peak and carbon neutrality” and the proposal of new power system, the construction of power system in metaverse is the trend in the future. Considering the application of metaverse applications in power systems, this paper used digital twin technology and internet-of-things technology to understand the metaverse, and then analyzed the power systems in the metaverse. Different from the current virtual reality, the metaverse has four characteristics: virtual fusion, diversification, immersion, economic system and civilization. Focusing on the above two means and four characteristics, this paper introduced the metaverse from the perspective of science and engineering, and expounded the framework and functions of power systems. Finally, this paper discussed the potential applications and prospects of metaverse in power systems.Keywords：metaverse;new power system;digital twin;internet-of-things89|177|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06Research on Optimal Allocation of Multi-Energy Complementary Project of Wind-Solar-Thermal Integration AI Introduction
Abstract：Multi-energy complementary project of wind-solar-thermal integration can play a coordinating and mutually beneficial role among different generations, and is one of the implementation paths for safe and efficient use of renewable energy, and achieving carbon neutrality and carbon peak. How to reasonably match the installed capacity of thermal power, wind power, photovoltaic power and the transmission capacity, to ensure the full consumption and efficient utilization of wind power and photovoltaic power, is the core issue of the multi-energy complementary project of wind-solar-thermal integration. Based on the analysis of the output characteristics and multi-energy complementary characteristics of different generations, an optimal allocation model of multi-energy complementary project of wind-solar-thermal integration was constructed with the objective of minimizing the total cost and maximizing the matching degree between the sending curve and the receiving load curve. The installed capacity of wind power, photovoltaic power and the transmission capacity were optimized at the planning level, and the thermal power operation mode, output curve and transmission curve were optimized at the operation level. According to the case analysis, the optimal allocation model can optimize and determine the installed capacity of wind power, photovoltaic power and the transmission capacity, so that different generations can coordinate with each other on monthly and daily time scales. The transmission curve is more friendly to the receiving-end grid, and the horizontal multi-energy complementary and longitudinal generation-load coordination are realized.Keywords：new energy;carbon neutrality;carbon peak;wind-solar-thermal integration;multi-energy complementary;optimal allocation;mixed integer programming93|94|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06Modal Parameter Identification of Low Frequency Oscillation in Power System Based on Ambient Data AI Introduction
Abstract：Low frequency oscillation is one of the key problem affecting the safe and stable operation of interconnected power system, variational modal decomposition (VMD) was used to extract low-frequency oscillation signals from ambient data, and a method of low-frequency oscillation modal identification for power systems discrete Fourier transform (DFT)-based curve fitting was proposed in this paper. Firstly, the DC component of ambient data signals was filtered by VMD decomposition to extract low-frequency oscillation signals. The number of VMD decomposition was determined by modal correlation coefficient, which improved the timeliness of signal decomposition. Secondly, the auto regressive moving average (ARMA) model of ambient data was established to simulate the generation of data signals. The DFT curve fitting of low-frequency oscillation signal autocorrelation function was used to estimate the Laplace transform coefficient and extract characteristic parameters of electromechanical oscillation. Finally, Simulation data and some measured phasor measurement unit (PMU) data are used to verify the feasibility and effectiveness of the method. The experiment shows that the sampling VMD algorithm and the curve fitting method based on DFT can extract the characteristic parameters of low-frequency oscillation, which effectively improves the real-time performance of electromechanical small interference stability.Keywords：low frequency oscillation;ambient data;auto regressive moving average (ARMA) model;variational modal decomposition (VMD);discrete Fourier transform (DFT) curve-fitting70|280|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06- Abstract：Wireless power transfer (WPT) can transmit electric wirelessly. It performs better under some paticular circumstances compared with the traditonal transmission mode. In the trend of building a smarter power system, the vast majority power supply problem of these smart equipments can be solved by using magnetic coupling resonant WPT. This paper introduced several possible application of magnetic coupling resonant WPT in power system, including the electric vehicle (EV) wireless charging system, substation power inspection robot wireless charging system and unmanned aerial vehicle (UAV) wireless charging system. Starting from the structure of the system, this paper compared and analyzed the recent research results, and drew conclusions finally. There still exists some issues to be settled in terms of charging efficiency, high-power charging, system reliability and double-direction WPT. At the end of this paper, several suggestions were proposed.Keywords：wireless power transfer (WPT);power system;coupled magnetic resonance116|772|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06
Smart Grid
Research Progress of Hydrogen Production by Methanol Reforming for Fuel Cell Power Generation AI Introduction
Abstract：Proton exchange membrane fuel cells take advantages of high efficiency, no pollution and good fuel adaptability. The green energy network formed by combining fuel cells with reliable hydrogen production is an effective way to achieve carbon neutrality. It is expected to promote the technological research and upgrading of new energy vehicles, unmanned air vehicles, ships and other industries those use fuel cells as electricity and thermal power source. However, a safe and stable hydrogen supply technology is a major bottleneck limiting the development of fuel cell power generation applications in mobile scenarios. Hydrogen production by in-situ methanol reforming is hopeful to make a breakthrough in mobile hydrogen source technology based on fuel cell. In this paper, the research progress of methanol reforming hydrogen production, the research progress of reactors for methanol reforming hydrogen production and the application of methanol reforming fuel cell power generation system were reviewed to provide reference and guidance for promoting the commercial development and application of methanol reforming fuel cell in the field of new energy.Keywords：carbon neutrality;methanol reforming for hydrogen production;fuel cell power generation;catalyst;reactor256|706|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06Analysis of Power Generation Technology Trend in 14th Five-Year Plan Under the Background of Carbon Peak and Carbon Neutrality AI Introduction
Abstract：The deep decarbonization of the energy and power industry will play a vital role in achieving the goal of carbon peak and carbon neutrality in China, and the important breakthrough point lies in the innovation of science and technology. Therefore, the current status of carbon peak and carbon neutrality at home and abroad were analyzed. In addition, the major deployment of China’s electric power industry to achieve the “3060 target” in detail was analyzed. Based on a lot of the latest energy and power policy documents, literatures and reports, the key power generation technologies in the process of carbon peak and carbon neutrality were analyzed. Furthermore, the development trend, emphasis and space layout of power generation-side technology in China during the 14th Five-Year Plan were analyzed and summed up. The research results will provide reference for grasping the important technical deployment and development direction of each power supply and realizing the high quality development of energy power industry.Keywords：carbon peak;carbon neutrality;power generation technology;energy and power39|295|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06Research on Application of Hydrogen in Power Industry Under “Double Carbon” Circumstance AI Introduction
Abstract：Hydrogen is a secondary clean energy which can be stored, moved and controlled. It is an ideal power energy carrier. The development and utilization of hydrogen as an energy source is an important means to tackle the climate change, ensure the national energy security and realize low-carbon transformation of the whole society. As an important greenhouse gas emission industry, the power industry, especially the power generation industry, should develop new energy applications including hydrogen as soon as possible to achieve zero-carbon energy transformation in the industry. According to the requirements of the “double carbon” goal, this paper analyzed the current situation of hydrogen application in China’s power industry, and put forward the main problems existing in the current hydrogen application. Based on the experience of power application development in major international hydrogen countries, combined the requirements of “re-electrification”, this paper put forward suggestions for the development of hydrogen power application from the perspectives of regulation formulation, policy support, financial innovation, and power industry scenario application. That is, during the “14th Five-Year Plan” period, it is necessary to make good technical reserves for hydrogen development, seize the opportunities for industrial development, and actively promote the transformation and upgrading of power system energy.Keywords：hydrogen;new energy;double carbon;carbon neutrality;zero-carbon transformation66|303|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06
Carbon Neutrality
- Abstract：Phosphoric acid fuel cell (PAFC) has become one of the fastest growing commercial fuel cells due to its short start-up time, no pollution and simple structure. According to the first and second laws of thermodynamics, the energy, exergy and ecology performances of PAFC were studied. The mathematical expressions of electric efficiency, output power, exergy destruction rate, exergy efficiency, ecological function and ecological coefficient of performance for fuel cell were derived. Considering the trade-off between various optimization criteria, the optimal working area of PAFC under different performance parameters was obtained. Finally, the effects of some main operating conditions and design parameters on the performance of PAFC system were discussed in detail. This work considers the benefits and losses of energy from the perspective of protecting natural resources, and the results can provide some theoretical support for the design of high-performance PAFC system.Keywords：phosphoric acid fuel cell (PAFC);energy efficiency;exergy;ecology characteristics58|156|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06
Heat Transfer Enhancement of a Cascaded Latent Heat Thermal Energy Storage System by Fins With Different Uneven Layouts AI Introduction
Abstract：The cascaded latent heat thermal energy storage (CLH-TES) is a kind of thermal energy storage technology with promising commercial prospects. The heat transfer enhancement of CLH-TES system by adding uneven number/height of fins for different phase change material (PCM) layers (uneven number/height layout) was numerically investigated. Firstly, for the system adding same number/height of fins for all the PCM layers (even number/height layout), the influences of number and height of fins on the charging and discharging performance were compared. Then, the charging and discharging performances of the systems with uneven number/height layout of fins were calculated. The results show, comparing to the even number layout,the system with uneven number layout can shorten the total time for the melting and solidification processes by 5.2% and increase the average charging rate by 12.6%. Besides, comparing to the even height layout, the system with uneven height layout can slightly decrease the total time for the melting and solidification processes but hardly affect the average charging and discharging rate. The findings can guidance the design of heat transfer enhancement to the CLH-TES with fins.Keywords：solar thermal power generation;cascaded latent heat thermal energy storage (CLH-TES);phase change material (PCM);heat transfer enhancement;uneven fins;numerical simulation45|144|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06- Abstract：The phase change thermal storage technology has broad application prospects in the field of solar thermal power generation and the fins can effectively increase the charge and release rate of the phase change heat storage. However, the dynamic nonlinear characteristics of phase change heat storage seriously restrict the optimization of fin structures. Therefore, this paper proposed a fast optimization algorithm for optimizing the fin structure of the phase change heat storage. The algorithm takes the shortest distance from the phase change material to the fin and the cold source as the optimization objective, and uses the genetic algorithm to optimize the structure of fin. This method solves the time-consuming problem of traditional numerical optimization methods. The one-level Y-shaped fin in a shell and tube phase change heat storage was taken as an example. Under the premise of meeting a certain amount of fin material, the width ratio and length of each branch and the angle between branches of Y-shaped fin were selected as the design variables, and the influence of the number of fins was analyzed. The results show that the optimization objective proposed in this paper is feasible, and the optimized fin structure presents an arrow shape. Under the heat release conditions studied in this paper, compared with the traditional Y-shaped fins, the optimized fin structure can shorten the complete solidification time by 41.3%-62.1% when the number of fins is 1-3.Keywords：phase change theermal storage;solidification process;Y-shaped fin;structure optimization;genetic algorithm63|170|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06
Energy Storage
Study on Maximum Power Tracking Strategy of 10 MW Medium Voltage Six-Phase Direct-Drive Permanent Magnet Wind Turbine AI Introduction
Abstract：In order to maximize the grid-connected power of high-power offshore wind turbines, a maximum power tracking strategy suitable for medium voltage six-phase permanent magnet synchronous generator (MVSPMSG) was proposed in the paper based on the use of MVSPMSG and distributed neutral point clamped converters to form a 10 MW wind power generation system. The optimal reference value of torque was given according to the speed feedback value, and the dual dq current control loop of the permanent magnet synchronous generator (PMSG) stator winding was designed through the feedforward decoupling method. The maximum power output control of the MVSPMSG was completed by the closed-loop combination of torque and double dq current loop. At the same time, a midpoint potential balance method with modulation coefficient and vector group selection coordinated adjustment was proposed to suppress the neutral point potential fluctuations on the DC side of the neutral point clamped converter. The method of adjusting the magnitude of modulation coefficient to suppress the fluctuation of the neutral point potential was first adopted. Meanwhile, the coordination vector group selection was applied to control the neutral point potential balance when the modulation factor exceeds the limit. Finally, a 10 MW permanent magnet wind power generation system model was established in MATLAB to verify the effectiveness of the control strategy proposed in the paper.Keywords：wind power;six-phase permanent magnet synchronous generator;distributed neutral point clamped converter;maximum power tracking;neutral point potential balance68|81|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06- Abstract：In order to evaluate the temporary overvoltage level of the wind power transmission system based on permanent magnet synchronous generator (PMSG) in case of load rejection, it is necessary to clarify the temporary overvoltage characteristics and its influencing factors after the fault. According to the mathematical analysis of the control and protection strategies of PMSG-based wind turbine, it was known that the DC bus rated voltage of the wind turbine, the modulation ratio of the grid side converter (GSC), the DC bus overvoltage protection setting, the wind turbine overvoltage protection setting and its action strategy were the main factors affecting the temporary overvoltage of the system. In addition, the type of reactive power compensation and configuration were also the factors influencing the temporary overvoltage of the system. PSCAD/EMTDC was used to verify the above factors. The results show that the relative control and protection strategies of PMSG-based wind turbine should be considered in wind turbine design and the calculation of the temporary overvoltage for wind farm.Keywords：offshore wind power;permanent magnet synchronous generator (PMSG);temporary overvoltage;control and protection strategy;reactive compensation55|287|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06
New Energy
Cost Benefit Analysis for Maintenance Strategy of Gas Turbine Inlet Filtration System AI Introduction
Abstract：Maintaining the normal operation of inlet filtration system is of great significance to ensure the operation efficiency of gas turbine unit. The maintenance economic benefit analysis model of gas turbine inlet filtration system was established, and the total maintenance cost was divided into three parts, i. e., initial cost, shutdown cost and performance degradation cost. Secondly, based on the model, the optimization methods of filter replacement and compressor washing maintenance cycle were proposed. Finally, the adjustment mode of maintenance strategy under the condition of abnormal degradation of inlet filtration system was explored. The results show that the economic benefits of gas turbine operation can be significantly improved by combining the degradation state evaluation of inlet filtration system and adjusting the maintenance cycle accordingly.Keywords：gas turbine;inlet filtration system;life cycle cost analysis;shutdown cost88|207|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06Study on Supercritical CO2 Cycle Coal-fired Power Generation System for Low Temperature Scenario AI Introduction
Abstract：Supercritical CO2 cycle can be used in the low temperature scenario to reduce the end temperature of the cycle and increase the cycle pressure ratio, which can well match with the coal-fired boiler to form a high-efficiency coal-fired power plant. Considering the climate and coal mine distribution, the coal mine bases in northern China, such as eastern Inner Mongolia and northern Xinjiang, have low atmospheric temperature conditions for more than four months in winter and spring, which is good for the constrution of high-efficiency supercritical CO2 coal-fired power plants. For the end temperature condition of 3-15 ℃, the thermodynamic calculation of supercritical CO2 cycle was carried out, and the economic and social benefits of the unit were analyzed. The results show that the supercritical CO2 cycle generator with 620 ℃/30 MPa initial parameters can obtain more than 48% of the net plant power generation efficiency in the low temperature scenario below 9 ℃, which is expected to surpass the efficiency of double-reheat ultra supercritical steam turbine unit. Supercritical CO2 cycle coal-fired power plants can supplement the power generation gap of renewable energy generation in winter and spring, and realize the efficient utilization of coal resources in the north through “North to South Power Transmission”.Keywords：supercritical CO2 cycle;coal-fired power generation;low temperature environment54|110|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06Thermodynamic Analysis of a New Combined Cooling, Heating and Power System Using CO2 Working Fluid AI Introduction
Abstract：In order to develop and utilize low-grade thermal energy such as solar energy, geothermal energy, industrial waste heat, etc, this paper proposed a combined cooling, heating and power system using CO2 as the working fluid. The system, coupling the supercritical CO2 Brayton power generation cycle and the transcritical CO2 compression refrigeration cycle by sharing the condenser, can provide users with electricity, refrigerant water and domestic hot water at the same time. This paper established the thermodynamic mathematical models of the proposed system in detail, and conducted numerical simulation of its operating conditions. The simulation results showed that the net output power of the simulated system is 140.34 kW, cooling capacity is 340.50 kW, heating capacity is 5 332.75 kW, thermal efficiency is 113.27%, and exergy efficiency is 41.24%. Then, on this basis, the sensitivity analysis of thermodynamic parameters of the system was carried out, and the effects of five thermodynamic parameters, including turbine inlet pressure, turbine outlet pressure, turbine inlet temperature, evaporator pressure and CO2 flow ratio of top cycle and bottom cycle, on the performance of the system were obtained.Keywords：carbon dioxide;combined cooling, heating and power;numerical simulation;parameter analysis46|81|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06Prediction and Comparison of Ash Fusion Temperatures Based on BP Neural Network and Least Squares Support Vector Machine AI Introduction
Abstract：To predict the slagging on heating surface of coal-fired boilers, BP neural network (BPNN) and least squares support vector machine (LSSVM) prediction models were established to predict ash fusion temperature, deformation temperature (DT) and softening temperature (ST). The models take ash metal oxide, SO3 content of ash and slagging evaluation indexes as independent variables, and take DT and ST as dependent variables. Regression analysis and error analysis show that when predicting DT with a large number of samples, the prediction accuracy of the two models is similar, and the confidence of prediction is over 95%. The correlation coefficients are both about 0.92, and the average relative errors are about 3.4%. When predicting ST with less samples, LSSVM model is better with a correlation coefficient of 0.950 52, which is higher than 0.904 26 of BPNN model. The average relative error is 4.98%, and the number of large error points is less than the BPNN model. Therefore, LSSVM model can predict DT and ST of fly ash more accurately.Keywords：BP neural network (BPNN);least squares support vector machine (LSSVM);ash fusion point;ash composition;slagging evaluation index88|171|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06Study on SO3 Removal Performance of Low-low Temperature Electrostatic Precipitator System AI Introduction
Abstract：In order to fully characterize the emission reduction performance of SO3 by low-low temperature electrostatic precipitator system (FGC+ESP), a method to test low-concentration SO3 was proposed, namely “two-stage controlled condensation + one-stage isopropanol absorption” sampling method, which can improve the accuracy of its test data. According to this method, in the pilot test, the SO3 removal efficiency of the low-low temperature electrostatic precipitator (LL-ESP) system (90 ℃ at ESP entrance) was 96.15%. In four groups of field measured data from three engineering projects, the SO3 removal efficiency of LL-ESP system was 69.1%-96.6%. The mechanism of SO3 adsorption and agglomeration by fly ash particles under low-low temperature conditions was verified. The study results can provide reference for the large-scale promotion and application of LL-ESP technology and SO3 emission reduction of coal-fired power plants.Keywords：coal-fired power plant;ultra-low emission;low-low temperature electrostatic precipitator system;SO3 test method;removal performance54|81|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06- Abstract：Wet electrostatic precipitation technology can effectively reduce the concentration of soot emission during thermal power generation. In order to study the effect of spray on the internal flow field of wet electrostatic precipitator during operation, the position of nozzle and the internal flow field of the wet electrostatic precipitator before and after using the nozzle were simulated by using the computational particle fluid dynamics (CPFD) method, the flow field, droplet distribution and spray trajectory were analyzed. The results show that when the nozzle is started, the velocity of flue gas near the nozzle is increased, and the velocity field of flue gas in the honeycomb tube is uneven. When the nozzle is arranged in the tube, it will accelerate the velocity of flue gas in the tube, which is not conducive to dust capture. The research results provide a theoretical reference for the adjustment of atomization region in practical engineering.Keywords：thermal power generation;computational particle fluid dynamics (CPFD);wet electrostatic precipitator;two-phase flow;numerical simulation;spray47|354|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06
Pareto Fronts of Mixed Coal Quality and Cost in Power Plant Based on Chance Constraints AI Introduction
Abstract：Coal blending models usually take the composition or properties of coal as constraints to optimize the cost of mixed coal for the blending scheme in power plant. Properties of coal are essentially not optimized with this kind of blending model. Therefore, the maximum likelihood quality of design coal of boiler was defined, when the compositions of raw coal can be regarded as random variables. A multi-objective optimization model of coal properties and cost based on chance constraint was established. Pareto fronts of the multi-objective model were presented by genetic algorithm. Analysis of Pareto fronts shows that the optimal data of coal properties and cost are reasonable, and the chance constraints are met well. The blending model can employ the stability of mixed coal as the optimization objective additionally. According to different characteristics of the generator unit and the actual coal to be blended, the optimization model can have different objectives and constraint combinations, which means the good flexibility and practicability.Keywords：thermal power generation;coal blending;maximum likelihood principle;chance constraint;multi-objective programming;Pareto fronts50|140|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06Performance Evaluation and Analysis of Key Parameters of SCR Ultra-low Emission for 1 000 MW Coal-fired Unit AI Introduction
Abstract：1 000 MW coal-fired unit, as one of the best domestic advanced units, the performance evaluation and analysis of the key parameters of its denitrification unit after the ultra-low emission reformation can provide reference and guidance for stable and safe operation of selective catalytic reduction (SCR) flue gas denitrification unit under ultra-low emission of coal-fired units. Taking the SCR denitrification unit of a 1 000 MW coal-fired unit that had achieved ultra-low denitrification emission as an example, the key operating parameters of the SCR denitrification unit were studied, such as denitrification efficiency, NOx concentration distribution at the inlet and outlet, ammonia escape, etc., the main performance of the denitrification unit was analyzed. The test results show that the overall performance of the SCR denitrification unit is good after the ultra-low emission transformation, but the problems of poor flow field uniformity and excessive ammonia escape still exist. Therefore, the adjustment of low nitrogen combustion, the optimization of ammonia injection, the uniformity test of flow field and the life-cycle management of catalyst should be strengthened.Keywords：1 000 MW coal-fired unit;selective catalytic reduction (SCR);ultra-low emission;performance evaluation99|92|0<HTML><L-PDF> <WORD> <Meta-XML>Updated：2025-06-06
Power Generation and Environmental Protection
