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- Abstract：With economic development, the world's energy structure will undergo major changes, and energy will be transformed to low-carbon, market-oriented and digitalized direction. China clearly proposes to achieve the goal of peaking carbon emissions by 2030 and achieving carbon neutrality by 2060. After the rapid development of electric power industry in China, a large number of large-scale, centralized energy system are constructed. By the end of 2019, total installed capacity of power generation was 2.01 billion kW in China, ranking the first of the world. However, there are many problems in energy field in China, such as unreasonable energy structure, tight constraints of resources and environment, low energy utilization efficiency, and insufficient flexible peak-regulating power supply. Therefore, efficient and clean energy utilization is the inevitable result of energy development and reform. This paper systematically analyzed the current situation of Energy system in Europe, the path of energy transformation in Europe and the role of distributed energy system in the process of energy transformation. It also analyzed the current situation of energy structure and faced situation in China, the role of distributed energy system in the energy transition, and the key path of China's future energy transition. At the same time, it further analyzed the development status of distributed energy system and the research status of domestic and foreign research institutions in the field of multi-energy complementary and efficient cascaded utilization. Finally, based on the implementation of regional strategies such as the Yangtze River Delta, Pearl River Delta, Tianjin-Beijing-Hebei Region, economic belt along Yangtze River and Hainan Free Trade Zone, this paper analyzed the development prospects of regional energy systems centered on distributed energy system.Keywords：distributed energy system;energy structure transition;regional energy system56|72|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
- Abstract：The regional energy supply system is powered by high-grade energy, which has problems such as high energy consumption and serious environmental pollution. However, based on the principle of "energy grade matching, and cascade utilization", through utilizing various high, medium and low temperature waste heat recovery technologies, the integrated energy efficiency of the system can be significantly improved, as well as the overall energy consumption and environmental pollution can be reduced, so it is of great concern. Through sorting out the technologies of waste heat recovery in the energy industry of steel, metallurgy and cement, and summarizing the technological progress of low-temperature grade energy waste heat recovery and its application to district heating/cooling systems, the characteristics of various waste heat recovery technologies in the heating/cooling systems were inquired. Finally, the feasibility and economy for application of waste heat recovery technologies in the field of the heating/cooling systems were analyzed with project cases. The results show that by utilizing the waste heat recovery technologies, the integrated energy efficiency of the district heating system can be improved by more than 8%. And the operation cost can be saved by 20% in the district cooling system through combining cold storage technology with waste heat recovery.Keywords：low temperature waste heat;waste heat recovery;district heating/cooling systems;energy saving103|549|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
Distributed Energy
- Abstract：Based on the probabilistic reliability, the configuration of the trough solar power plant was optimized. Firstly, the SAM software was used to simulate the 50 MW trough solar power plant. Then, by considering the randomness caused by the uncertainty factor, the uncertainty model of the trough solar power plant based on its solar multiple, the full load hours of storage system and the row spacing distance of the collector was established by neural network-Monte Carlo method. Secondly, the reliability calculation model was established, levelized cost of energy (LCOE), capacity factor (CF) and total generation efficiency were selected as key performance indicators (KPI), then the KPI were optimized based on the reliability indexes of each KPI. Finally, the optimal configuration of each design parameter obtained under the uncertainty model was compared with the optimization result under the deterministic model. Since the influence of the uncertainty factor is considered, the calculation result under the uncertainty model is closer to the actual situation.Keywords：trough solar power plant;probabilistic reliability;optimization design;uncertainty;neural network28|52|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
- Abstract：The methods of damage state detection and fault diagnosis of wind turbine blades were reviewed, and the research status and problems worthy of study were pointed out. The fault types and corresponding fault mechanism of wind turbine blades, several commonly used methods of state detection and fault diagnosis of wind turbine blades were summarized. The advantages and disadvantages of various detection techniques were analyzed. It is found that all kinds of damage detection technology can effectively detect defects in wind turbine blades, but single detection technology has been unable to meet the requirements of blade damage fault detection. Therefore, a variety of detection techniques can be used to conduct comprehensive detection of the blade.Keywords：wind turbine blade;fault diagnosis;status detection139|1754|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
- Abstract：In order to solve the problem that the unmanned aerial vehicle (UAV) image is not clear due to the influence of fog particles, a UAV image dehazing algorithm based on simple linear iterative clustering (SLIC) optimization was proposed. Through the physical model of fog imaging, the prior law of dark channel, homogeneous filtering and SLIC algorithm, the influence of white area and uneven light in power inspection image was improved, the efficiency of UAV image dehazing was improved, and the adaptive calculation of atmospheric light intensity parameters was carried out to prevent the distortion in the dehazing process. The experimental results show that the algorithm can effectively restore the original details of the power inspection image. Through the comparison of subjective visual evaluation and fusion of a variety of objective evaluation indexes, it shows the superiority of the algorithm compared with the traditional algorithms.Keywords：wind farm;power inspection;image dehazing;homogeneous filtering;simple linear iterative clustering (SLIC)51|167|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
- Abstract：Spatial correlation prediction of wind speed is an effective method for wind power prediction. In order to improve the effect of spatial correlation prediction of wind speed, the basic equations of atmospheric motion in dynamic meteorology were analyzed, and pressure gradient force, Earth gravity force and the friction force are the basic forces of atmospheric motion. In the time scale of short-term and super-short-term wind power prediction, gravity and friction of the earth can usually be regarded as known quantities or invariants, so pressure gradient force is the primary force causing wind. The value of development spatial correlation and prediction was quantitative analyzed on the southeastern coast of China. It shows that the spatial correlation of monsoon region in China is obviously higher than that in Europe and America, and the southeast coast of offshore wind power are significantly higher than the land, especially suitable for spatial correlation prediction. The spatial correlation of atmospheric pressure prediction is one of the reliable basics methods for prediction of monsoon wind power in China.Keywords：wind power prediction;wind speed;atmospheric pressure;pressure difference;spatial correlation54|307|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
- Abstract：In view of the uncertainty of power generation in renewable energy, especially wind power and photovoltaic power generation, the improved K-means clustering method was used to segment the state of power generation. Firstly, the uncertainty model of wind power and photovoltaic power generation was established, and the appropriate probability density function was used to fit. Then the basic K-means clustering algorithm was improved by combining density clustering and proposed hybrid evaluation function, to solve the problem that the initial clustering center and the number of clusters were difficult to select. The improved K-means clustering was used to cluster the wind and photovoltaic scenes in a certain place, thus transforming the uncertainty problem into a deterministic problem. Finally, the practicability of the proposed method was verified by analyzing an example of scenario division.Keywords：wind power generation;photovoltaic power generation;density clustering;K-Means clustering;scenario division91|470|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
- Abstract：Studying on new energy developing roadmap helps to provide the important reference for the formulation of medium and long-term development plan of new energy in China. This paper put forward a set of analysis methods and models of development roadmap involving resources evaluations, total capacity, developing sequences and layout according to energy development strategy and characteristics of new energy development in China. The wind, photovoltaic and photothermal power generation developing capacity sequences and layout in 2030 and 2050 were also studied. The results show that there will be a rapid speed for China's new energy development, pushing the new energy to become the dominated power after 2030. Wind power will be concentered in "Three North" areas, while the solar power presents a combination of centralized development and distributed utilization.Keywords：new energy;developing road map;developing capacity;developing sequence49|834|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
New and Renewable Energy
- Abstract：Under the development trend of continuous growth of the peak of power load and large scale renewable energy penetration, in order to achieve renewable energy accommodation and stabilize power grid fluctuation, the means of demand side civil controllable load participating in demand response can be adopted for regulation. In particular, the control of family controllable load is extended from single family control to multiple families, and finally large-scale load group control can be realized. Firstly, the research results of demand response mode, load classification modeling and control strategy in recent years were summarized, and the general models of various loads were summarized based on the characteristics of load power consumption. Then, the characteristics and shortcomings of multi-objective optimization control strategy, hierarchical control strategy, multi-time scale control strategy and priority control strategy were analyzed. Finally, the further research direction of different control strategies in the control of demand response was pointed out. And combined with the situation of our country, the development prospect of demand response was prospected from the perspective of civil controllable load participating in demand response regulation.Keywords：renewable energy accommodation;power system;demand response;controllable load;control strategy;smart grid57|534|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
- Abstract：As a major branch of integrated energy system, micro-grid is widely used in the local consumption of distributed generation. With the introduction of cold, heat and gas, the requirement of micro-grid security control is becoming higher and higher. The grid-connected and off-grid mode of micro-grid and the transition process between two operating states were analyzed, furthermore, a control strategy based on improved virtual synchronous generator (VSG) model was proposed. By using appropriate virtual impedance, the characteristics of synchronous reactance were effectively simulated, which ensured the stability of off-grid operation and makes the transition from grid-connected mode to off-grid mode smooth without adding additional control. An improved pre-synchronization control model was proposed for the switching from off-grid mode to grid-connected mode, which could accurately and quickly track the voltage amplitude, frequency and phase. Finally, the model was simulated in Matlab/Simulink environment with a practical example to verify the correctness and advantages of the proposed model.Keywords：micro-grid;seamless switch;virtual synchronous generator (VSG);virtual impedance;improved pre-synchronization control77|499|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
- Abstract：Aiming at the problem of low voltage ride through (LVRT) of the generation side uncontrollable rectifying permanent magnet wind turbine in the low voltage microgrid, the operating characteristics of the permanent magnet synchronous generator (PMSG) wind turbine during the grid voltage drop were researched. Based on the analysis of the DC link voltage instability mechanism, a LVRT control strategy was proposed combined operation method of the maximum current output of the grid side converter and chopper circuit. After judging the operating status of the wind turbine, the chopper circuit and the grid-side converter were coordinated controlled. In the case of full load, the DC link voltage was controlled by the chopper circuit, and the grid-side converter outputs the maximum current. In the case of light load, the DC link voltage was controlled by a conventional voltage loop, and the residual current capacity of the grid-side converter was used to transmit reactive power. The simulation results of the system show that LVRT can be achieved effectively by the generation side uncontrollable rectifying permanent magnet wind turbine under two working conditions.Keywords：low voltage microgrid;wind turbine;low voltage ride through (LVRT);chopper circuit;maximum current output53|338|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
- Abstract：Voltage source converter (VSC) is the main power electronic components of wind power, photovoltaic and converter stations. It's control mode and parameter setting have important influence on system operation. Based on real time digital simulator (RTDS) hardware-in-loop simulation and digital simulation, a new method of parameter fitting applied to characterize physical VSC was proposed. Taking a typical single VSC grid connected system model as an example, firstly, based on the principle of phase-locked loop (PLL), an adaptive observation coordinate system was proposed to compare and fit the step response of two simulation models. Then the fitting methods of PLL, current inner loop and DC voltage outer loop in VSC control system were introduced separately. Self-adaptive observational coordinate system was used in the process of current inner loop parameter fitting. Finally, the efficiency of the proposed method was verified by the comparative analysis of simulations.Keywords：voltage source controller (VSC);parameter fitting;self-adaptive observation coordinate system;phase-locked loop (PLL)83|175|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
- Abstract：In order to improve the ability of clean energy consumption and the reliability of power supply, distribution network operation is attracting more and more attention. In view of the non-convergence of the traditional forward and backward substitution method, an improved power flow algorithm for distribution network with ring network was proposed by combining the loop analysis method with the forward and backward generation power flow algorithm. The branch current was decomposed to compensate the split-point current, and the non-convergence phenomenon was changed. The validity and accuracy of the algorithm were verified by data simulation with Matlab.Keywords：distribution network;distributed generation;loop operation;loop analysis;forward and backward substitution method26|293|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
Energy Internet
- Abstract：In order to study the reasons for serious corrosion problem of induced draft fan blades of a 2×300 MW circulating fluidized bed unit which were blended burning solid waste fuel, the samples of the corroded blade and ash from different positions were taken. The analysis results of X-Ray diffractomer (XRD), scanning electron microscope (SEM) and X-ray fluorescence (XRF) show that Cl element is found in the rust samples and on the surface of the blades, and no trace of S element is found. Therefore, it is determined that the cause of the corrosion of the blades is Cl corrosion. Through the test of ash samples at different positions of the boiler, it is found that the ash hardened on the air preheater and the ash collected by bag filter behind the semi-dry flue gas desulfurization are enriched in Cl, which is the key to cause the Cl corrosion of the equipment. The blended burning solid waste fuel and sludge are the main sources of Cl. The enrichment of Cl in the ash hardened on the air preheater is found related to NH3 escaped from selective non-catalytic reduction, the reason of Cl enrichment in desulfurized ash needs further study.Keywords：circulating fluidized bed;boiler;solid waste fuel;blade corrosion;Cl corrosion42|311|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
- Abstract：The frequent fast closing action of the governing valve in a 1000 MW ultra-supercritical unit occurred during the cold running process, which caused the valve body to sway greatly and could not continue to speed up. The problem had not been solved by governing the impulse parameters, checking the solenoid valve oil circuit, retesting the control oil quality and other measures. Therefore, starting from the speed control logic, the conditions of fast closing action and the change of proportional integral (PI) regulating quantity were analyzed. It was concluded that the main factor affecting the total flow instruction (the final valve position opening) in the process of fast closing is the feedforward change of speed regulation, not the change of PI output. Based on this analysis, the boundary value of feedforward quantity of speed control was calculated without changing the impulse parameters and the flow characteristic curve of the valve. Through many attempts to establish the optimal value of feedforward quantity, the fast closing action of the governing valve can be avoided due to the unreasonable parameter setting in the control logic. After optimization, the actual speed rises steadily with the set value, the valve opening is opened linearly, and there is no more frequent swing, which meets the requirements of speed up control.Keywords：ultra-supercritical unit;frequent fast closing;speed control;regulating quantity;feedforward quantity;optimum value44|420|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
- Abstract：With the development of gas-steam combined cycle power generation technology, the requirements of generator capacity and parameters are constantly improving. The generators of H class gas-steam combined cycle generator unit need to have more stable, efficient and safe starting requirements. It also stimulates improvement of static frequency converter (SFC) technology facing more challenge. SFC technology has displayed its advantages in controlling accurately, flexibly and efficiently. Meanwhile, SFC brings more harmonic components to influence the quality of power system. SFC start-up simulation model of H class gas turbine generator was built by Matlab/Simulink to simulate the generator start-up process, the evolvement of various parameters was researched and the proportion of harmonic components during the generator starting was analyzed. The simulation results show that the SFC start-up can increase the speed of the generator flexibly by adjusting the frequency and amplitude of the output current, and the impact of the generator start-up is small. However, large numbers of nonlinear electrical components built in SFC will cause higher proportion of harmonic components appear in power system and influence power quality. Therefore, two optimization schemes for SFC access were proposed to suppress harmonic effects, which are the scheme of adding input reactor before SFC and the scheme of changing generator end of input power supply. Through the simulation, it was proved that the two schemes can effectively suppress or reduce the harmonic effect and meet the requirements of power quality.Keywords：gas-steam combined cycle power generation;static frequency converter (SFC);variable frequency speed regulation;heavy duty gas turbine generator;harmonic analysis65|416|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
- Abstract：Because the traditional steam sootblowing technology has a dead corner, it needs a lot of high quality steam, and the safety of the steam is affected by the scouring of the heating surface. Therefore, in recent years, many new power plants tend to adopt built-in array acoustic sootblower in the low-temperature flue to purge the low-temperature reheater, low-temperature superheater and economizer. Combined with the application of acoustic sootblower in a 660 MW power plant, the economic evaluation was studied. The sootblowing economy was evaluated by two indexes:boiler efficiency at boiler side and steam turbine thermal efficiency at turbine side. The boiler anti-balance method was used to calculate the boiler efficiency variation when the exhaust gas temperature changed 1℃ under a certain load. The increase of boiler efficiency was calculated by the decrease of flue gas temperature after sootblowing, and the decrease of coal consumption was further calculated. By using the calculation method of heat carrying out system by working medium in the equivalent enthalpy drop method, the influence of sootblowing steam on the heat consumption of steam turbine was obtained, and the increase of coal consumption was further calculated. The economic gain of acoustic sootblower was obtained by considering the economic evaluation of boiler side and steam turbine side. The results show that compared with the conventional steam sootblower, the annual cost saving of the built-in array acoustic sootblower is more than 1 million yuan. In addition, it will have better energy-saving effect for units with poor economic performance for many years.Keywords：coal-fired generating units;built-in array acoustic sootblower;energy-saving analysis;economic evaluation27|426|0<HTML><L-PDF> <Meta-XML>Updated：2025-07-04
Power Generation and Enviromental Protection
