Due to the impact of source-load prediction power errors and uncertainties,the actual operation of the park will have a wide range of fluctuations compared with the expected state,resulting in its inability to achieve...Due to the impact of source-load prediction power errors and uncertainties,the actual operation of the park will have a wide range of fluctuations compared with the expected state,resulting in its inability to achieve the expected economy.This paper constructs an operating simulation model of the park power grid operation considering demand response and proposes a multi-time scale operating simulation method that combines day-ahead optimization and model predictive control(MPC).In the day-ahead stage,an operating simulation plan that comprehensively considers the user’s side comfort and operating costs is proposed with a long-term time scale of 15 min.In order to cope with power fluctuations of photovoltaic,wind turbine and conventional load,MPC is used to track and roll correct the day-ahead operating simulation plan in the intra-day stage to meet the actual operating operation status of the park.Finally,the validity and economy of the operating simulation strategy are verified through the analysis of arithmetic examples.展开更多
This study proposes a combined hybrid energy storage system(HESS) and transmission grid(TG) model, and a corresponding time series operation simulation(TSOS) model is established to relieve the peak-shaving pressure o...This study proposes a combined hybrid energy storage system(HESS) and transmission grid(TG) model, and a corresponding time series operation simulation(TSOS) model is established to relieve the peak-shaving pressure of power systems under the integration of renewable energy. First, a linear model for the optimal operation of the HESS is established, which considers the different power-efficiency characteristics of the pumped storage system, electrochemical storage system, and a new type of liquid compressed air energy storage. Second, a TSOS simulation model for peak shaving is built to maximize the power entering the grid from the wind farms and HESS. Based on the proposed model, this study considers the transmission capacity of a TG. By adding the power-flow constraints of the TG, a TSOS-based HESS and TG combination model for peak shaving is established. Finally, the improved IEEE-39 and IEEE-118 bus systems were considered as examples to verify the effectiveness and feasibility of the proposed model.展开更多
An optimized device structure for reducing the RESET current of phase-change random access memory （PCRAM） with blade-type like （BTL） phase change layer is proposed. The electrical thermal analysis of the BTL cell ...An optimized device structure for reducing the RESET current of phase-change random access memory （PCRAM） with blade-type like （BTL） phase change layer is proposed. The electrical thermal analysis of the BTL cell and the blade heater contactor structure by three-dimensional finite element modeling are compared with each other during RESET operation. The simulation results show that the programming region of the phase change layer in the BTL cell is much smaller, and thermal electrical distributions of the BTL cell are more concentrated on the TiN/GST interface. The results indicate that the BTL cell has the superiorities of increasing the heating efficiency, decreasing the power consumption and reducing the RESET current from 0.67mA to 0.32mA. Therefore, the BTL cell will be appropriate for high performance PCRAM device with lower power consumption and lower RESET current.展开更多
Objective With the cranial aneurysm’s 3D-computational hemodynamics numerical simulation,we can get the cranial aneurysms and its ’s mother arteries ’blood flow rate,path and wall shearing stress and so on. Taking ...Objective With the cranial aneurysm’s 3D-computational hemodynamics numerical simulation,we can get the cranial aneurysms and its ’s mother arteries ’blood flow rate,path and wall shearing stress and so on. Taking use of the contrast analysis of the hemodynamics result and the findings in operation,we try to find hemodynamic character and mechanism of rupture展开更多
In this paper, a new concept of simulation operating system (SIMOS) is described. A detailed definition of SIMOS is given, and two integrated simulation software (IPSOS and IMSS) are introduced based on SIMOS.
A multi-objective improved genetic algorithm is constructed to solve the train operation simulation model of urban rail train and find the optimal operation curve.In the train control system,the conversion point of op...A multi-objective improved genetic algorithm is constructed to solve the train operation simulation model of urban rail train and find the optimal operation curve.In the train control system,the conversion point of operating mode is the basic of gene encoding and the chromosome composed of multiple genes represents a control scheme,and the initial population can be formed by the way.The fitness function can be designed by the design requirements of the train control stop error,time error and energy consumption.the effectiveness of new individual can be ensured by checking the validity of the original individual when its in the process of selection,crossover and mutation,and the optimal algorithm will be joined all the operators to make the new group not eliminate on the best individual of the last generation.The simulation result shows that the proposed genetic algorithm comparing with the optimized multi-particle simulation model can reduce more than 10%energy consumption,it can provide a large amount of sub-optimal solution and has obvious optimization effect.展开更多
A CNC simulation system based on intemet for operation training of manufacturing facility and manufacturing process simulation is proposed. Firstly, the system framework and a rapid modeling method of CNC machine tool...A CNC simulation system based on intemet for operation training of manufacturing facility and manufacturing process simulation is proposed. Firstly, the system framework and a rapid modeling method of CNC machine tool are studied under the virtual environment based on PolyTrans and CAD software. Then, a new method is proposed to enhance and expand the interactive ability of virtual reality modeling language（VRML） by attaining communication among VRML, JavaApplet, JavaScript and Html so as to realize the virtual operation for CNC machine tool. Moreover, the algorithm of material removed simulation based on VRML Z-map is presented. The advantages of this algorithm include less memory requirement and much higher computation. Lastly, the CNC milling machine is taken as an illustrative example for the prototype development in order to validate the feasibility of the proposed approach.展开更多
Impulse turbine, working as a typical self-rectifying turbine, is recently utilized for the oscillating water column（OWC） wave energy converters, which can rotate in the same direction under the bi-directional air f...Impulse turbine, working as a typical self-rectifying turbine, is recently utilized for the oscillating water column（OWC） wave energy converters, which can rotate in the same direction under the bi-directional air flows. A numerical model established in Fluent is validated by the corresponding experimental results. The flow fields, pressure distribution and dimensionless evaluating coefficients can be calculated and analyzed. Effects of the rotor solidity varying with the change of blade number are investigated and the suitable solidity value is recommended for different flow coefficients.展开更多
A real-time operating system （RTOS）, also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-base...A real-time operating system （RTOS）, also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-based task division method is introduced and the multi-task software architecture is built in the software system for electronic unit pump （EUP） system. The V-model software development process is used to control algorithm of each task. The simulation results of the hardware-in-the-loop simulation system （HILSS） and the engine experimental results show that the OS is an efficient real-time kernel, and can meet the real-time demands of EUP system; The built multi-task software system is real-time, determinate and reliable. V-model development is a good development process of control algorithms for EUP system, the control precision of control system can be ensured, and the development cycle and cost are also decreased.展开更多
The development of micro-grid renewable energy system in China has achieved rapid growth in recent years,and the micro-grid renewable energy system has been drawing more and more attention by its flexible operation.Du...The development of micro-grid renewable energy system in China has achieved rapid growth in recent years,and the micro-grid renewable energy system has been drawing more and more attention by its flexible operation.Due to the randomness,fluctuation,uncertainty of the wind and photovoltaic renewable generation,abundant flexibility is required to meet the needs of safe,reliable and independent operation of the micro-grid energy system.We need to connect large energy systems to accept outside assistance when the micro-grid renewable energy system is short of adjustment capability.Independent operation and network operation will affect the economic benefit of the micro-grid energy system,so it is practically meaningful to study on the economic benefit evaluation of the micro-grid renewable energy system.This paper proposes a micro-grid energy system operation simulation model about wind and photovoltaic generation,the uncertainty of which is tackled based on the scenario generation and extraction techniques.Based on the proposed indices,the economic benefit could be evaluated by simulating the micro-grid energy system operation.The proposed method is validated by a real micro-grid energy system.展开更多
When integrating the generation of large-scale renewable energy,such as wind and solar energy,the supply and demand sides of the new power system will exhibit high uncertainty.Pumped storage power stations can improve...When integrating the generation of large-scale renewable energy,such as wind and solar energy,the supply and demand sides of the new power system will exhibit high uncertainty.Pumped storage power stations can improve flexible resource supply regulation in the power system,which is the key support and important guarantee for building low-carbon,safe,and efficient new power systems.Limited by the current operation mode and electricity price mechanism,the pumped storage power station cost cannot be effectively recovered,and the value cannot be reasonably compensated,resulting in difficult return on investment,single investment subjects,and notable industry development difficulties.According to the operational requirements of the new power system,combined with the various functions of pumped storage power stations,the value of pumped storage power stations in the new power system was analyzed.Based on the equivalent value substitution principle and system operation simulation,a pumped storage value evaluation method for the new power system was proposed.The new power system operation was simulated considering the dispatching model of wind and photovoltaic power abandonment penalties.Under the same dispatching objectives,the output of various power sources and power generation operating costs with and without pumped storage power stations in the system were compared.From economic,safety,social,and environmental benefit perspectives,a quantitative model of the pumped storage power station value was established,covering seven dimensions:asset investment savings,power generation operating cost reduction,flexible adjustment capability improvement,system resilience enhancement,power outage loss reduction,renewable energy consumption,and emission reduction promotion.Based on the new power system operation and planning data for southern China,the value of typical pumped storage power stations was analyzed,and the results showed that with new power system’s construction and development,the value of pumped storage power stations is increasing,and the value structure is closely related to power grid characteristics.This value evaluation method could provide references for pumped storage investment decisions,subsidy policies,and price mechanisms to fully utilize the role of pumped storage power stations and promote high-quality development of new power systems.展开更多
In a UHV DC and AC combined system the UHVDC’s blocking fault becomes the most serious load balance contingency of the receiving end power system due to its large capacity.The amount of contingency reserve thus is la...In a UHV DC and AC combined system the UHVDC’s blocking fault becomes the most serious load balance contingency of the receiving end power system due to its large capacity.The amount of contingency reserve thus is largely increased.This paper proposes three distinct schemes for allocating contingency reserve to cover the power shortage caused by UHVDC’s blocking fault,and compares the economic cost of these schemes.An operation simulation method using a unit commitment technique is proposed for evaluating the operation costs associated with increasing contingency reserve.A real case study for a Jiangsu Province power system in China is presented to demonstrate that the best scheme is to share the contingency reserve with neighborhood power systems through the transmission capacity of UHVAC lines.展开更多
As massive distributed energy resources(DERs)are integrated into distribution networks(DNs)and the distribution automation facilities are widely deployed,the DNs are evolving to active distribution networks(ADNs).This...As massive distributed energy resources(DERs)are integrated into distribution networks(DNs)and the distribution automation facilities are widely deployed,the DNs are evolving to active distribution networks(ADNs).This paper introduces the architecture and main function modules of an integrated distribution management system(IDMS)and its applica-tions in China.This system consists of three subsystems,including the real-time operation and control system(OCS),outage management system(OMS),and operator training simulator(OTS).The OCS has a hierarchical architecture with three levels,including the local controller for DER clusters,the optimization of DNs incorporated with multi-clusters,and the coordina-tion operation of integrated transmission&distribution(T&D)networks.The OMS is developed based on the geographical information system(GIS)and coordinated with OCS.While in the OTS,both the ADN and its host transmission network(TN)are simulated to make the simulation results more credible.The main functions of the three subsystems and their interaction data flows are described and some typical application scenarios are also presented.展开更多
基金supported by the Science and Technology Project of State Grid Shanxi Electric Power Research Institute:Research on Data-Driven New Power System Operation Simulation and Multi Agent Control Strategy(52053022000F).
文摘Due to the impact of source-load prediction power errors and uncertainties,the actual operation of the park will have a wide range of fluctuations compared with the expected state,resulting in its inability to achieve the expected economy.This paper constructs an operating simulation model of the park power grid operation considering demand response and proposes a multi-time scale operating simulation method that combines day-ahead optimization and model predictive control(MPC).In the day-ahead stage,an operating simulation plan that comprehensively considers the user’s side comfort and operating costs is proposed with a long-term time scale of 15 min.In order to cope with power fluctuations of photovoltaic,wind turbine and conventional load,MPC is used to track and roll correct the day-ahead operating simulation plan in the intra-day stage to meet the actual operating operation status of the park.Finally,the validity and economy of the operating simulation strategy are verified through the analysis of arithmetic examples.
基金supported by the State Grid Science and Technology Project (No.52999821N004)。
文摘This study proposes a combined hybrid energy storage system(HESS) and transmission grid(TG) model, and a corresponding time series operation simulation(TSOS) model is established to relieve the peak-shaving pressure of power systems under the integration of renewable energy. First, a linear model for the optimal operation of the HESS is established, which considers the different power-efficiency characteristics of the pumped storage system, electrochemical storage system, and a new type of liquid compressed air energy storage. Second, a TSOS simulation model for peak shaving is built to maximize the power entering the grid from the wind farms and HESS. Based on the proposed model, this study considers the transmission capacity of a TG. By adding the power-flow constraints of the TG, a TSOS-based HESS and TG combination model for peak shaving is established. Finally, the improved IEEE-39 and IEEE-118 bus systems were considered as examples to verify the effectiveness and feasibility of the proposed model.
基金Supported by the Strategic Priority Research Program of the Chinese Academy of Sciences under Grant No XDA09020402the National Integrate Circuit Research Program of China under Grant No 2009ZX02023-003+1 种基金the National Natural Science Foundation of China under Grant Nos 61261160500,61376006,61401444 and 61504157the Science and Technology Council of Shanghai under Grant Nos 14DZ2294900,15DZ2270900 and 14ZR1447500
文摘An optimized device structure for reducing the RESET current of phase-change random access memory （PCRAM） with blade-type like （BTL） phase change layer is proposed. The electrical thermal analysis of the BTL cell and the blade heater contactor structure by three-dimensional finite element modeling are compared with each other during RESET operation. The simulation results show that the programming region of the phase change layer in the BTL cell is much smaller, and thermal electrical distributions of the BTL cell are more concentrated on the TiN/GST interface. The results indicate that the BTL cell has the superiorities of increasing the heating efficiency, decreasing the power consumption and reducing the RESET current from 0.67mA to 0.32mA. Therefore, the BTL cell will be appropriate for high performance PCRAM device with lower power consumption and lower RESET current.
文摘Objective With the cranial aneurysm’s 3D-computational hemodynamics numerical simulation,we can get the cranial aneurysms and its ’s mother arteries ’blood flow rate,path and wall shearing stress and so on. Taking use of the contrast analysis of the hemodynamics result and the findings in operation,we try to find hemodynamic character and mechanism of rupture
文摘In this paper, a new concept of simulation operating system (SIMOS) is described. A detailed definition of SIMOS is given, and two integrated simulation software (IPSOS and IMSS) are introduced based on SIMOS.
基金This work was supported by the Youth Backbone Teachers Training Program of Henan Colleges and Universities under Grant No.2016ggjs-287the Project of Science and Technology of Henan Province under Grant Nos.172102210124 and 202102210269.
文摘A multi-objective improved genetic algorithm is constructed to solve the train operation simulation model of urban rail train and find the optimal operation curve.In the train control system,the conversion point of operating mode is the basic of gene encoding and the chromosome composed of multiple genes represents a control scheme,and the initial population can be formed by the way.The fitness function can be designed by the design requirements of the train control stop error,time error and energy consumption.the effectiveness of new individual can be ensured by checking the validity of the original individual when its in the process of selection,crossover and mutation,and the optimal algorithm will be joined all the operators to make the new group not eliminate on the best individual of the last generation.The simulation result shows that the proposed genetic algorithm comparing with the optimized multi-particle simulation model can reduce more than 10%energy consumption,it can provide a large amount of sub-optimal solution and has obvious optimization effect.
基金Selected from Proceedings of the 7th International Conference on Frontiers of Design and Manufacturing (ICFDM'2006)This project is supported by National Natural Science Foundation of China (No.50775047)Scientific and Technological Foundation of Guangdong Province,China(No.2004B10201032).
文摘A CNC simulation system based on intemet for operation training of manufacturing facility and manufacturing process simulation is proposed. Firstly, the system framework and a rapid modeling method of CNC machine tool are studied under the virtual environment based on PolyTrans and CAD software. Then, a new method is proposed to enhance and expand the interactive ability of virtual reality modeling language（VRML） by attaining communication among VRML, JavaApplet, JavaScript and Html so as to realize the virtual operation for CNC machine tool. Moreover, the algorithm of material removed simulation based on VRML Z-map is presented. The advantages of this algorithm include less memory requirement and much higher computation. Lastly, the CNC milling machine is taken as an illustrative example for the prototype development in order to validate the feasibility of the proposed approach.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.51279190 and 51311140259)the Shandong Province Natural Science Foundation for Distinguished Young Scholars(Grant No.JQ201314)
文摘Impulse turbine, working as a typical self-rectifying turbine, is recently utilized for the oscillating water column（OWC） wave energy converters, which can rotate in the same direction under the bi-directional air flows. A numerical model established in Fluent is validated by the corresponding experimental results. The flow fields, pressure distribution and dimensionless evaluating coefficients can be calculated and analyzed. Effects of the rotor solidity varying with the change of blade number are investigated and the suitable solidity value is recommended for different flow coefficients.
文摘A real-time operating system （RTOS）, also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-based task division method is introduced and the multi-task software architecture is built in the software system for electronic unit pump （EUP） system. The V-model software development process is used to control algorithm of each task. The simulation results of the hardware-in-the-loop simulation system （HILSS） and the engine experimental results show that the OS is an efficient real-time kernel, and can meet the real-time demands of EUP system; The built multi-task software system is real-time, determinate and reliable. V-model development is a good development process of control algorithms for EUP system, the control precision of control system can be ensured, and the development cycle and cost are also decreased.
基金the Ministry of Education in China(MOE)Project of Humanities and Social Sciences(Grant No.16YJC630141)the Social Science Foundation of Shaanxi Province(Grant No.2015R016)+1 种基金the Soft Science Research Program of Shaanxi Province(Grant No.2017KRM034)the Social Science Foundation of Xi’an City(Grant No.18J141).
文摘The development of micro-grid renewable energy system in China has achieved rapid growth in recent years,and the micro-grid renewable energy system has been drawing more and more attention by its flexible operation.Due to the randomness,fluctuation,uncertainty of the wind and photovoltaic renewable generation,abundant flexibility is required to meet the needs of safe,reliable and independent operation of the micro-grid energy system.We need to connect large energy systems to accept outside assistance when the micro-grid renewable energy system is short of adjustment capability.Independent operation and network operation will affect the economic benefit of the micro-grid energy system,so it is practically meaningful to study on the economic benefit evaluation of the micro-grid renewable energy system.This paper proposes a micro-grid energy system operation simulation model about wind and photovoltaic generation,the uncertainty of which is tackled based on the scenario generation and extraction techniques.Based on the proposed indices,the economic benefit could be evaluated by simulating the micro-grid energy system operation.The proposed method is validated by a real micro-grid energy system.
基金Supported by the Innovation Project of the China Southern Power Grid Co.,Ltd. (020000KK52210005).
文摘When integrating the generation of large-scale renewable energy,such as wind and solar energy,the supply and demand sides of the new power system will exhibit high uncertainty.Pumped storage power stations can improve flexible resource supply regulation in the power system,which is the key support and important guarantee for building low-carbon,safe,and efficient new power systems.Limited by the current operation mode and electricity price mechanism,the pumped storage power station cost cannot be effectively recovered,and the value cannot be reasonably compensated,resulting in difficult return on investment,single investment subjects,and notable industry development difficulties.According to the operational requirements of the new power system,combined with the various functions of pumped storage power stations,the value of pumped storage power stations in the new power system was analyzed.Based on the equivalent value substitution principle and system operation simulation,a pumped storage value evaluation method for the new power system was proposed.The new power system operation was simulated considering the dispatching model of wind and photovoltaic power abandonment penalties.Under the same dispatching objectives,the output of various power sources and power generation operating costs with and without pumped storage power stations in the system were compared.From economic,safety,social,and environmental benefit perspectives,a quantitative model of the pumped storage power station value was established,covering seven dimensions:asset investment savings,power generation operating cost reduction,flexible adjustment capability improvement,system resilience enhancement,power outage loss reduction,renewable energy consumption,and emission reduction promotion.Based on the new power system operation and planning data for southern China,the value of typical pumped storage power stations was analyzed,and the results showed that with new power system’s construction and development,the value of pumped storage power stations is increasing,and the value structure is closely related to power grid characteristics.This value evaluation method could provide references for pumped storage investment decisions,subsidy policies,and price mechanisms to fully utilize the role of pumped storage power stations and promote high-quality development of new power systems.
基金supported by National Natural Science Foundation of China(No.51325702)Science-Technology Project of State Grid Corporation of China(No.GHJS1500009)State Grid Excellent Innovation Foundation of Tsinghua University(No.2011079).
文摘In a UHV DC and AC combined system the UHVDC’s blocking fault becomes the most serious load balance contingency of the receiving end power system due to its large capacity.The amount of contingency reserve thus is largely increased.This paper proposes three distinct schemes for allocating contingency reserve to cover the power shortage caused by UHVDC’s blocking fault,and compares the economic cost of these schemes.An operation simulation method using a unit commitment technique is proposed for evaluating the operation costs associated with increasing contingency reserve.A real case study for a Jiangsu Province power system in China is presented to demonstrate that the best scheme is to share the contingency reserve with neighborhood power systems through the transmission capacity of UHVAC lines.
基金the National Science Foundation of China(No.U2066601 and No.51725703).
文摘As massive distributed energy resources(DERs)are integrated into distribution networks(DNs)and the distribution automation facilities are widely deployed,the DNs are evolving to active distribution networks(ADNs).This paper introduces the architecture and main function modules of an integrated distribution management system(IDMS)and its applica-tions in China.This system consists of three subsystems,including the real-time operation and control system(OCS),outage management system(OMS),and operator training simulator(OTS).The OCS has a hierarchical architecture with three levels,including the local controller for DER clusters,the optimization of DNs incorporated with multi-clusters,and the coordina-tion operation of integrated transmission&distribution(T&D)networks.The OMS is developed based on the geographical information system(GIS)and coordinated with OCS.While in the OTS,both the ADN and its host transmission network(TN)are simulated to make the simulation results more credible.The main functions of the three subsystems and their interaction data flows are described and some typical application scenarios are also presented.
