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- Abstract：Power system transient stability control based on response is one of the main applications of wide-area measurement system (WAMS). WAMS that can obtain real-time dynamic response data of the whole power grid, provides a strong technical support to the responsebased power system transient stability. The key technologies of the response-based power system transient stability are summarized, mainly including three aspects, i.e., post-fault trajectory prediction of transient stability, transient stability assessment, transient stability emergency control. The disadvantages of the existing methods were presented, as well as the characteristics of the response-based transient stability control technology were summarized, and on this basis the key problems to be solved in the future were pointed out.Keywords：wide-area measurement system (WAMS);transient stability;post-fault trajectory prediction;transient stability assessment;emergency control43|503|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
- Abstract：The mode of multi-micro-grid connection mainly has single grid connected mode and joint coordinated grid connection mode. The different working state of micro power supply inside the two types of grid connection leads to different generating cost. To reduce the cost of power generation, an optimal scheduling model of multi micro grid energy and an optimal scheduling model for single micro grid were established on the premise of satisfying the constraints of the related micro power supply. Due to the low accuracy and slow convergence rate of the traditional artificial fish swarm algorithm, an improved artificial fish swarm algorithm (SA_AFSA algorithm) based on simulated annealing algorithm was proposed, which overcomes the shortcoming of the traditional fish swarm algorithm. Combined with a specific example, the algorithm is used to solve the economic optimal scheduling problem of single micro-grid and multi-micro-grid, and the cost of power generation under two grid connection modes was compared. The experimental results show that under the premise of only considering the economy, the cost of generation and coordination of multi micro-grid is lower than that of single micro-grid.Keywords：multi-micro-grid;single grid connection;joint coordination and grid connection;optimal scheduling;SA_AFSA algorithm;generation cost32|239|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
- Abstract：With the government's supporting and incentives policy, the electric vehicle market obtains rapid development, which greatly stimulates the construction and operation of electric vehicle charging facilities. And this brings great impact on the safety of power grid. This paper introduced the security risk factors of electric vehicle charging on the power grid. Based on identifying the factors, the impact of electric vehicle charging and discharging on the distribution grid was analyzed by simulation analysis, and the security risks was also assessed. Finally the management controls of security risks in the planning, construction, operation, and self-management of electric vehicle charging facilities are proposed.Keywords：electric vehicle;charging facilities;power grid;simulation analysis;management control79|514|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
- Abstract：The development of the Energy Internet is the general trend, requiring both a high-quality top-level design and a mature underlying technology. Starting from energy storage, which is the important technical support of Energy Internet, the goals of energy storage to achieve and the basic requirements for energy storage in Energy Internet are analyzed. Then the main functions of the energy storage system are summarized from the power generation side, system side, and user side. In addition to peak-load shifting, and improving power quality, the main functions include realizing energy network coupling and promoting new energy usage modes. According to the function of the energy storage system, the function of energy storage in the Energy Internet is analyzed. Finally, the corresponding relationship between the Energy Internet's demand for energy storage, the main function of energy storage, and the mode of action of energy storage was pointed out.Keywords：energy internet;energy storage;demand;function;action manner38|310|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
Energy Internet
- Abstract：To have a better understanding about coal gasification process in HTW pressurized fluidized bed, the model was developed using process simulation software Aspen Plus. Gas composition, low heating value(LHV), gas yield and cold gas efficiency were simulated with the change in the oxygen/coal ratio and steam/coal ratio. The results show that with the oxygen/coal ratio increaseing, outlet temperature decreases, the yield of CO increases, H2 first increases and then decreases slightly, CO and CH4 decreases, gas yield increases, LHV decreases, cold gas efficiency decreases. The usual operating temperature of high-temperature Winkler(HTW) pressurized fluidized bed gasifier is about 1050℃, and the corresponding oxygen/coal ratio is 0.71. The steam/coal ratio less affects the operating performance of HTW pressurized fluidized bed gasifier. The result of the simulation was meaningful for the following research about coal gasification process in HTW pressurized fluidized bed and the design of the gasifier.Keywords：HTW pressurized fluidized gasifier;Aspen Plus;coal gasification46|273|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
- Abstract：With the increasing share of renewable energy in power system, more and more coal-fired power units participate flexibility generation. For clarifying the air emission characteristics of flexibility generation, the operation history data of two subcritical coal-fired power units (600 MW and 300 MW) are used for regression analysis. In normal cyclic operation, power ramping-down will lead to a little increase in coal consumption rate and CO2 emissions factor. Meanwhile, the NOx emissions factor will decrease firstly and then increase when ramping down and the amplitude of variation is little in clean flue gas. The SO2 emissions factor will decrease a little while dust factor will increase a little when ramping down. In deep cycling operation, the increase in coal consumption rate and CO2 emissions factor will be much larger, while the NOx and dust emissions factors will increase substantially when SO2 emissions factor continues to decrease in clean flue gas. In start-up process, the NOx and dust emissions are much larger while SO2 emissions are slightly smaller than regular operating conditions. In addition, larger ramping rate has remarkable impact on NOx and SO2 in untreated flue gas and on dust in clean flue gas in deep cycling conditions.Keywords：coal-fired power unit;flexibility generation;air emissions characteristics;regression analysis56|307|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
- Abstract：In order to reduce environmental effect by open coal yard in power plant, coal yard in power plants is required to be transformed into a closed space. The closed transformation of the coal yard adopts a large steel structure. After the structural optimization design of the large-scale steel structure by the finite element analysis software, the output graphics cannot meet the requirements of the construction drawings. This article uses AutoLISP programming to automatically standardize the AutoCAD graphics output by finite element software, this method alleviates the heavy manual modification work and shortens the post processing time of the output drawings, it will greatly improve the working efficiency of large-scale steel structure design.Keywords：coal-fired power plant;coal yard;steel house;drawings normalization51|195|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
- Abstract：Flow distribution in electrostatic-fabric integrated precipitator is one of the most important factors for affecting collection efficiency. The standard k-ε turbulence model was used to simulate flow field distribution at five kinds of filtration velocity. The results show that obvious partition of flow velocity was observed, the high-speed zone was observed at the lower space of the electrostatic precipitator dust bag, the area was minimum when the filtration rate of speed was 1.6 m/min, at the same time, the filter bag narrow stream was observed at the gathering area, which the bag loading unevenness was increased. In the lower region of the bag dust, bag dust chamber area and net cross-sectional area representatives were tested. The unevenness was smallest at 0.8 m/min of filtration velocity, and areas were increasing with speed bag dust increases, but increases with height overall have shown a downward trend.Keywords：electrostatic-fabric integrated precipitator;filtration velocity;numerical simulation26|81|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
- Abstract：Direct dry cooling system adopts large-scale axial flow fan group to cool exhaust steam of turbine. So the noise of direct dry cooling system becomes one of the hazards of power plants. By using computational fluid dynamics software Fluent, the simulation of flow field and noise forecast of direct dry cooling cell and system were performed in this paper. The changes of flow field and noise of ACCs (air-cooled steam condensers) were simulated after increasing the noise reduction wall. The large eddy simulation was applied to analyze the flow field. Noise forecast was proceeded by means of the unsteady and implicit solver. The results show that the porous sound-absorbing materials decorated inside the wind wall have no effect on the flow field of ACCs. But they could effectively reduce the noise level of ACCs, especially reducing the low frequency noise.Keywords：direct dry cooling;axial flow fan;flow field simulation;noise forecast;noise reduction measures38|238|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
- Abstract：In recent years, the wind and PV power curtailment is becoming more and more serious, and the demand for deep peaking capacity of coal-fired power plants is also increasing. In this paper, the flexibility transformation of 350MW super-critical cogeneration units was studied combined with the relevant policies of thermal power unit's deep peak shaving compensation in North China. The optimal scheme suitable for our factory was obtained through analyzing several mainstream flexibility transformation technologies, comparing the advantages and disadvantages, investment costs and operating costs of various technologies, evaluating the effect of unit flexibility on later operation combined with the compensation for peak adjustment in the region. The results show that the low-pressure cylinder zero output heating technology is the lowest cost scheme coping thermoelectric decoupling. When the unit price of standard coal is below 700 yuan per ton, the unit is not suitable for peak adjustment and should be loaded with more load; and when the price of the standard coal is above 700 yuan per ton, it is possible to reduce unit load to reduce loss through peak regulation.Keywords：cogeneration unit;flexibility transformation;deep peak regulation;wind power curtailment;photovoltaic energy curtailment76|118|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
- Abstract：The article explains the heating supply technology retrofit for 135 MW and 300 MW grade units at high back pressure condition. The performance indicators of high back pressure operational conditions are obtained through performance test after retrofit. At high back pressure operational mode, the heat consumption rate of pure condensing condition is among 3690~3740 kJ/(kW·h), the heat consumption rate of extraction steam condition is among 3690~4060 kJ/(kW·h). The effect of retrofit technology, cold end design parameters and operational parameters on performance indicators has been analyzed. For the same 135 MW grade unit, under full load condition, the difference of circulating water being 3500 t/h, the difference of condenser pressure is 15 kPa. The difference of generator power at full condition is 26.7 MW. By peak regulation capacity test during heat supply period, the peak regulation range and adaptation with high back pressure operational mode have been determined. The power load regulation capacity of 300 MW unit is 65 MW, being 22% of rated capacity before retrofit. The power load regulation capacity of 135 MW unit is 35~60 MW, being 26%~44% of rated capacity before retrofit. The reason that resulting peak regulation range narrow and peak regulation decrease also have been analyzed.Keywords：extraction condensing unit;high back pressure retrofit;heating supply with circulating water;performance indicators;peak regulation capacity78|287|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
- Abstract：Cabinet A and cabinet B of generator protection group of a power plant respectively reported "protection action of stator zero sequence high voltage section", which caused unit trip. It was found that the generator outlet potential transformer(PT) B phase 5042PT was obviously overheated. The accident process, through the breakdown PT finish straight resistance, insulation, excitation characteristic curve, and no-load current test, PT interturn short circuit are the main reasons of the unit tripping. In view of how to find early export PT insulation fault, the corresponding measures to prevent cracking was proposed. Specification requirements must be strictly according to the forecast to complete generator export PT partial discharge, triple frequency withstand voltage test, etc. In addition, the trend analysis was carried out on the data of various routine pre-test projects to detect the abnormality timely. The analysis of PT turn-to-turn short circuit fault at the generator outlet plays a good role in finding out the safety hidden danger and improving the reliability of the equipment. The regular completion of relevant tests in accordance with the standard requirements and the emphasis on the trend analysis of test data can effectively reduce the occurrence probability of the same type of accidents and reduce the scope of accidents.Keywords：generator outlet PT;interturn short circuit;zero sequence voltage95|273|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
- Abstract：A PID control system based on feedforward prediction was designed according to the thought of predictive control, in view of the existing model of electro-hydraulic servo control system.. The control system does not rely on the exact mathematical model of the object, and uses the characteristics of the fast and adaptive predictive control to determine the current control of the system by the combination of rolling optimization and PID. The simulation results show that the new type of controller can satisfy control performance requirements of the existing electro-hydraulic servo control system, achieving the rapid precise control of the system.Keywords：forecast;PID control;feedforward;electrohydraulic servo61|315|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
Power Generation and Environment Protection
- Abstract：Due to the complementarity of wind power and hydropower, the coordinated operation of the two has been studied a lot, but in the consumption process of "bundling" the wind power and hydropower, balancing the interests of all parties is a key issue in the coordinated operation of wind power and hydropower. Only by ensuring the fairness of the distribution of benefits, the cooperation of wind power and hydropower can be promoted for a long time, thus ensuring the maximum benefit. Then it summarizes and analyzes the advantages and disadvantages of the wind power and hydropower cooperative operation, its advantages and disadvantages were analyzed. Considering the characteristics of wind power and hydropower coordinated operation, it points out that risk input capacity, input resource level and resource utilization rate will affect the profit distribution result. The research direction was also prospected.Keywords：coordinated operation of wind power and hydropower;profit distribution;influencing factor19|128|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
- Abstract：With the rapid development of wind power, the large-scale wind power integration brings a new range of issues in dispatching operation of provincial power grid. Firstly, the important characteristics of wind power output and its specific impact on power grid operation were analyzed. Secondly, in order to gain a better grasp of the influence caused by wind power combined to the grid, the impact characteristic index was established. Then, according to the actual output data of multiple wind farm groups, the distribution characteristics, volatility and correlation of wind power output time series were analyzed from different time and space scales. Finally, based on a provincial grid data and its integrated wind power output data, the impact of wind power time-sequence characteristic on power grid, such as the frequency regulation, peak load regulation was studied, which can provide the reference for wind power optimal dispatching of power grid.Keywords：wind farm group output;time-sequence characteristic;spatial and temporal scale;frequency control;peak load regulation76|534|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
- Abstract：The design of nuclear power equipment is concerned with structural integrity and stability of the equipment in running process. Using the finite element analysis software, the stress calculation and seismic analysis were carried out on the fram structure of the air-cooled chiller unit in a nuclear power station. The calculation results show that the structure strength and bolts strength of the air-cooled chiller can meet the requirements of all working conditions. Finally some suggestions for the design of unit frame were put forward, which could provide reference for the optimization design and seismic performance improvement of air-cooled chiller in nuclear power plant in the future.Keywords：nuclear power plant;air-cooled chiller;framing;anchoring parts;seismic analysis33|252|0<HTML><L-PDF> <Meta-XML>Updated：2025-06-06
New and Renewable Energy
