The management and control system of improving quality, reducing cost and increasing efficiency aims to establish a corresponding incentive target system around the business tasks and development goals of the enterpri...The management and control system of improving quality, reducing cost and increasing efficiency aims to establish a corresponding incentive target system around the business tasks and development goals of the enterprise, guides the company all units and departments to strengthen the internal management, full of all aspects of mining efficiency potential, enhances the endogenous development of the enterprise power, so as to effectively cope with the market crisis, improve enterprise efficiency. With the end of the "golden decade" of thermal power generation enterprise market, the production and operation of thermal power generation enterprises are increasingly difficult. In order to effectively deal with the power market under the declining price environment, tap the internal efficiency potential of enterprises, and realize the loss and gain. Combined with the characteristics and actual situation of the enterprise, on the basis of summarizing previous experience, focusing on the high-quality development of the enterprise, highlighting value creation, making up for shortcomings, promoting reform and increasing benefits, the paper proposes to construct a management and control system to improve quality, reduce cost and increase efficiency.展开更多
Wet Flue Gas Desulfurization(WFGD)unit based upon spray scrubber has beenwidely employed to control SO_(2) emissions from flue gas in coal-fired power plant.To clarify the dependence of desulfurization performance on ...Wet Flue Gas Desulfurization(WFGD)unit based upon spray scrubber has beenwidely employed to control SO_(2) emissions from flue gas in coal-fired power plant.To clarify the dependence of desulfurization performance on inter-phase transfer behaviors with non-ideal contacting patterns of flue gas and slurry droplets,three regions in spray scrubber are distinguished in terms of gas-slurry flow structures using CFD method in the Eulerian-Lagrangian framework.A comprehensive model is established by involving the transfer process between two phases and chemical reactions in aqueous phase,which is validatedwith the measured data froma WFGD scrubber of 330 MW coal-fired power unit.Numerical results show that the overall uniformity degree of flue gas in whole scrubber is largely determined by the force-balanced droplets in the middle part of scrubber,which is dominated by counter-current mode.Both momentum transfer behavior and SO_(2) chemical absorption process present the synchronicity with the evolution of gas-slurry flow pattern,whilst the heat transfer together with H_(2)O evaporation has little effect on overall absorption process.Three regions are firstly defined as Gas Inlet Region(GIR),Dominant Absorption Region(DAR)and Slurry Dispersed Region(SDR)from the bottom to top of scrubber.SO_(2) is mainly scrubbed in DAR,which provides much more intensive interaction between two phases compared to GIR or SDR.A better understanding of the desulfurization process is obtained from the fundamental relationship between transport phenomena and chemical reactions based upon the complicated hydrodynamics of gas-slurry two-phase flow,which should be useful for designing and optimizing the scrubber in coal-fired power unit.展开更多
Superheated steam temperature control system is an indispensable part of the unit, its performance and reliability has become an important factor to ensure the safety and economy of the unit. When the superheated stea...Superheated steam temperature control system is an indispensable part of the unit, its performance and reliability has become an important factor to ensure the safety and economy of the unit. When the superheated steam temperature is high, the thermal efficiency of the unit is relatively high. However, when the superheated steam temperature is too high, the metal material of the steam turbine cannot bear it. If the temperature is too low, the efficiency of the unit will be affected. The stability of superheated steam temperature is very important for the safe and economic operation of the unit, so there are higher requirements for its control. In the whole control system of power plant, there are many factors affecting superheated steam temperature, including steam flow disturbance, flue gas flow disturbance and desuperheating water disturbance. The spray desuperheating method is widely used at present, which is beneficial to the safe operation of superheater. Combined with the operation characteristics of the 300MW unit in Diaobingshan power plant, this paper studies and analyzes the superheated steam temperature control strategy, designs a set of control scheme under all working conditions, sets the relevant control parameters, and verifies its effect through simulation. The superheated steam temperature is regulated by two-stage spray desuperheating, and the first stage desuperheating is arranged at the inlet of platen superheater for coarse regulation of steam temperature. The secondary desuperheater is arranged at the inlet of high temperature superheater for fine adjustment. The superheated steam temperature at the outlet of the boiler is maintained at the set value by adjusting the water spray quantity of the primary and secondary superheaters.展开更多
For a long time, with the continuous development of power enterprises, more and more construction projects need contractors to participate in the completion. While contractors provide business support for power enterp...For a long time, with the continuous development of power enterprises, more and more construction projects need contractors to participate in the completion. While contractors provide business support for power enterprises and reduce enterprise costs, the contradiction between the pursuit of profit maximization and safe production is also increasingly prominent. In recent years, the direct responsibility and main responsibility accidents of the contractors account for the vast majority of the safety accidents in power enterprises. The safety management of contractors has become a weak link and a difficult problem in the safety management of electric power enterprises. It is also the main problem that hinders the safety production of electric power enterprises and is the top priority in the safety management. This paper studies and analyzes the safety management of contractors, effectively reduces the occurrence of contractor accidents in exploration and practice, and steadily improves the safety management level of power enterprises.展开更多
In practical quantum key distribution(QKD)systems,a single photon-detector(SPD)is one of the most vulnerable components.Faint after-gate attack is a universal attack against the detector.However,the original faint aft...In practical quantum key distribution(QKD)systems,a single photon-detector(SPD)is one of the most vulnerable components.Faint after-gate attack is a universal attack against the detector.However,the original faint after-gate attack can be discovered by monitoring the photocurrent.This paper presents a probabilistic generalization of the attack,which we refer to as probabilistic faint after-gate attack,by introducing probability control modules.Previous countermeasures for photocurrent monitoring may fail in detecting the eavesdropper under some specific probabilities.To mitigate this threat,we provide a method to determine the detectable boundary in the limitation of precision of photocurrent monitoring,and investigate the security of QKD systems under such boundaries using the weak randomness model.展开更多
Along with the rapid development of the industrialization process in our country in recent years, overall for industrialized production and construction in China put forward the new requirements. It is important to en...Along with the rapid development of the industrialization process in our country in recent years, overall for industrialized production and construction in China put forward the new requirements. It is important to ensure that industrial production in the process of construction safety and quality, especially in recent years, our country the development of the circulating fluidized bed boiler equipment affected by the current state and factory industrial market. With the rapid development of science and technology in recent years, many new technologies and new equipment will be applied to the overall design of circulating fluidized bed boiler. This paper will be circulating fluidized bed boiler slag removal system in my company's actual application of a detailed introduction, clear circulating fluidized bed boiler slag removal system today's development.展开更多
Nanoparticles succeeded to enhance the dielectric properties of industrial insulation but the presence of voids inside the power cable insulation still leads to formation high electrical stress inside power cable insu...Nanoparticles succeeded to enhance the dielectric properties of industrial insulation but the presence of voids inside the power cable insulation still leads to formation high electrical stress inside power cable insulation material and collapse.In this paper,the dielectric strength of new design nanocomposites has been deduced as experimental work done to clarify the benefit of filling nanoparticles with different patterns inside dielectrics.Also,it has been studied the effect of electrical stress distribution in presence of air,water and copper impurities with different shapes(cylinder,sphere and ellipse)inside insulation of single core.In simulation model,it has been used finite element method(FEM)for estimating the electrostatic field distribution in power cable insulation.It has been applied new strategies of nanotechnology techniques for designing innovative polyvinyl chloride insula-tion materials by using nanocomposites and multi-nanocomposites.Finally,this research succeeded to remedy different partial discharges(PD)patterns according to using certain types and concentrations of nanoparticles.展开更多
The push for renewable energy emphasizes the need for energy storage systems(ESSs)to mitigate the unpre-dictability and variability of these sources,yet challenges such as high investment costs,sporadic utilization,an...The push for renewable energy emphasizes the need for energy storage systems(ESSs)to mitigate the unpre-dictability and variability of these sources,yet challenges such as high investment costs,sporadic utilization,and demand mismatch hinder their broader adoption.In response,shared energy storage systems(SESSs)offer a more cohesive and efficient use of ESS,providing more accessible and cost-effective energy storage solutions to overcome these obstacles.To enhance the profitability of SESSs,this paper designs a multi-time-scale resource allocation strategy based on long-term contracts and real-time rental business models.We initially construct a life cycle cost model for SESS and introduce a method to estimate the degradation costs of multiple battery groups by cycling numbers and depth of discharge within the SESS.Subsequently,we design various long-term contracts from both capacity and energy perspectives,establishing associated models and real-time rental models.Lastly,multi-time-scale resource allocation based on the decomposition of user demand is proposed.Numerical analysis validates that the business model based on long-term contracts excels over models operating solely in the real-time market in economic viability and user satisfaction,effectively reducing battery degradation,and leveraging the aggregation effect for SESS can generate an additional increase of 10.7%in net revenue.展开更多
Under the back-side windy condition,the convection and radiation heat transfer characteristics in an iso-flux upward-facing cylindrical cavity were studied by three-dimensional numerical simulation.The impacts of cavi...Under the back-side windy condition,the convection and radiation heat transfer characteristics in an iso-flux upward-facing cylindrical cavity were studied by three-dimensional numerical simulation.The impacts of cavity tilt angle,wind incident angle and wind speed on convection and radiation heat transfer Nusselt number Nuc and Nur were analyzed,and the possible explanations for their impacts were presented.Results show that due to the disturbance of wind,the influence of cavity tilt angle becomes more complicated and is related to wind incident angle and wind speed.The variation of Nuc or Nur with wind incident angle is different for different cavity tilt angles.Despite of the changes of cavity tilt angle or wind incident angle,the Nuc increases with the wind speed while the Nur presents a declination with the increasing of wind speed.Hence,compared with cavity tilt angle and wind incident angle,wind speed may be the dominant factor affecting or controlling the convective and radiation heat transfer of cavity.展开更多
Hong-Ou-Mandel(HOM)interference is one of the most important experimental phenomena in quantum optics.It has drawn considerable attention with respect to quantum cryptography and quantum communication because of the a...Hong-Ou-Mandel(HOM)interference is one of the most important experimental phenomena in quantum optics.It has drawn considerable attention with respect to quantum cryptography and quantum communication because of the advent of the measurement device independent(MDI)quantum key distribution(QKD)protocol.Here,we realize HOM interference,having a visibility of approximately 38.1%,using two independent heralded single-photon sources(HSPSs).The HOM interference between two independent HSPSs is a core technology for realizing the long-distance MDI QKD protocol,the quantum coin-tossing protocol,and other quantum cryptography protocols.展开更多
文摘The management and control system of improving quality, reducing cost and increasing efficiency aims to establish a corresponding incentive target system around the business tasks and development goals of the enterprise, guides the company all units and departments to strengthen the internal management, full of all aspects of mining efficiency potential, enhances the endogenous development of the enterprise power, so as to effectively cope with the market crisis, improve enterprise efficiency. With the end of the "golden decade" of thermal power generation enterprise market, the production and operation of thermal power generation enterprises are increasingly difficult. In order to effectively deal with the power market under the declining price environment, tap the internal efficiency potential of enterprises, and realize the loss and gain. Combined with the characteristics and actual situation of the enterprise, on the basis of summarizing previous experience, focusing on the high-quality development of the enterprise, highlighting value creation, making up for shortcomings, promoting reform and increasing benefits, the paper proposes to construct a management and control system to improve quality, reduce cost and increase efficiency.
基金This work was supported by the National Natural Science Foundation of China(51706070 and U1910215)the Fundamental Research Funds for the Central Universities(2018ZD03,2020MS008 and 2020MS078).
文摘Wet Flue Gas Desulfurization(WFGD)unit based upon spray scrubber has beenwidely employed to control SO_(2) emissions from flue gas in coal-fired power plant.To clarify the dependence of desulfurization performance on inter-phase transfer behaviors with non-ideal contacting patterns of flue gas and slurry droplets,three regions in spray scrubber are distinguished in terms of gas-slurry flow structures using CFD method in the Eulerian-Lagrangian framework.A comprehensive model is established by involving the transfer process between two phases and chemical reactions in aqueous phase,which is validatedwith the measured data froma WFGD scrubber of 330 MW coal-fired power unit.Numerical results show that the overall uniformity degree of flue gas in whole scrubber is largely determined by the force-balanced droplets in the middle part of scrubber,which is dominated by counter-current mode.Both momentum transfer behavior and SO_(2) chemical absorption process present the synchronicity with the evolution of gas-slurry flow pattern,whilst the heat transfer together with H_(2)O evaporation has little effect on overall absorption process.Three regions are firstly defined as Gas Inlet Region(GIR),Dominant Absorption Region(DAR)and Slurry Dispersed Region(SDR)from the bottom to top of scrubber.SO_(2) is mainly scrubbed in DAR,which provides much more intensive interaction between two phases compared to GIR or SDR.A better understanding of the desulfurization process is obtained from the fundamental relationship between transport phenomena and chemical reactions based upon the complicated hydrodynamics of gas-slurry two-phase flow,which should be useful for designing and optimizing the scrubber in coal-fired power unit.
文摘Superheated steam temperature control system is an indispensable part of the unit, its performance and reliability has become an important factor to ensure the safety and economy of the unit. When the superheated steam temperature is high, the thermal efficiency of the unit is relatively high. However, when the superheated steam temperature is too high, the metal material of the steam turbine cannot bear it. If the temperature is too low, the efficiency of the unit will be affected. The stability of superheated steam temperature is very important for the safe and economic operation of the unit, so there are higher requirements for its control. In the whole control system of power plant, there are many factors affecting superheated steam temperature, including steam flow disturbance, flue gas flow disturbance and desuperheating water disturbance. The spray desuperheating method is widely used at present, which is beneficial to the safe operation of superheater. Combined with the operation characteristics of the 300MW unit in Diaobingshan power plant, this paper studies and analyzes the superheated steam temperature control strategy, designs a set of control scheme under all working conditions, sets the relevant control parameters, and verifies its effect through simulation. The superheated steam temperature is regulated by two-stage spray desuperheating, and the first stage desuperheating is arranged at the inlet of platen superheater for coarse regulation of steam temperature. The secondary desuperheater is arranged at the inlet of high temperature superheater for fine adjustment. The superheated steam temperature at the outlet of the boiler is maintained at the set value by adjusting the water spray quantity of the primary and secondary superheaters.
文摘For a long time, with the continuous development of power enterprises, more and more construction projects need contractors to participate in the completion. While contractors provide business support for power enterprises and reduce enterprise costs, the contradiction between the pursuit of profit maximization and safe production is also increasingly prominent. In recent years, the direct responsibility and main responsibility accidents of the contractors account for the vast majority of the safety accidents in power enterprises. The safety management of contractors has become a weak link and a difficult problem in the safety management of electric power enterprises. It is also the main problem that hinders the safety production of electric power enterprises and is the top priority in the safety management. This paper studies and analyzes the safety management of contractors, effectively reduces the occurrence of contractor accidents in exploration and practice, and steadily improves the safety management level of power enterprises.
文摘In practical quantum key distribution(QKD)systems,a single photon-detector(SPD)is one of the most vulnerable components.Faint after-gate attack is a universal attack against the detector.However,the original faint after-gate attack can be discovered by monitoring the photocurrent.This paper presents a probabilistic generalization of the attack,which we refer to as probabilistic faint after-gate attack,by introducing probability control modules.Previous countermeasures for photocurrent monitoring may fail in detecting the eavesdropper under some specific probabilities.To mitigate this threat,we provide a method to determine the detectable boundary in the limitation of precision of photocurrent monitoring,and investigate the security of QKD systems under such boundaries using the weak randomness model.
文摘Along with the rapid development of the industrialization process in our country in recent years, overall for industrialized production and construction in China put forward the new requirements. It is important to ensure that industrial production in the process of construction safety and quality, especially in recent years, our country the development of the circulating fluidized bed boiler equipment affected by the current state and factory industrial market. With the rapid development of science and technology in recent years, many new technologies and new equipment will be applied to the overall design of circulating fluidized bed boiler. This paper will be circulating fluidized bed boiler slag removal system in my company's actual application of a detailed introduction, clear circulating fluidized bed boiler slag removal system today's development.
基金The present work was supported by the Nanotechnology Research Center at Aswan University that is established by aiding the Science and Technology Development Fund(STDF),Egypt,Grant No:Project ID 505,2009-2011.
文摘Nanoparticles succeeded to enhance the dielectric properties of industrial insulation but the presence of voids inside the power cable insulation still leads to formation high electrical stress inside power cable insulation material and collapse.In this paper,the dielectric strength of new design nanocomposites has been deduced as experimental work done to clarify the benefit of filling nanoparticles with different patterns inside dielectrics.Also,it has been studied the effect of electrical stress distribution in presence of air,water and copper impurities with different shapes(cylinder,sphere and ellipse)inside insulation of single core.In simulation model,it has been used finite element method(FEM)for estimating the electrostatic field distribution in power cable insulation.It has been applied new strategies of nanotechnology techniques for designing innovative polyvinyl chloride insula-tion materials by using nanocomposites and multi-nanocomposites.Finally,this research succeeded to remedy different partial discharges(PD)patterns according to using certain types and concentrations of nanoparticles.
基金supported by National Natural Science Foundation of China(No.U2066601).
文摘The push for renewable energy emphasizes the need for energy storage systems(ESSs)to mitigate the unpre-dictability and variability of these sources,yet challenges such as high investment costs,sporadic utilization,and demand mismatch hinder their broader adoption.In response,shared energy storage systems(SESSs)offer a more cohesive and efficient use of ESS,providing more accessible and cost-effective energy storage solutions to overcome these obstacles.To enhance the profitability of SESSs,this paper designs a multi-time-scale resource allocation strategy based on long-term contracts and real-time rental business models.We initially construct a life cycle cost model for SESS and introduce a method to estimate the degradation costs of multiple battery groups by cycling numbers and depth of discharge within the SESS.Subsequently,we design various long-term contracts from both capacity and energy perspectives,establishing associated models and real-time rental models.Lastly,multi-time-scale resource allocation based on the decomposition of user demand is proposed.Numerical analysis validates that the business model based on long-term contracts excels over models operating solely in the real-time market in economic viability and user satisfaction,effectively reducing battery degradation,and leveraging the aggregation effect for SESS can generate an additional increase of 10.7%in net revenue.
基金funded by National Key Research and Development Program of China(Grant No.2017YFB0602002,and Grant No.2016YFC0203700)。
文摘Under the back-side windy condition,the convection and radiation heat transfer characteristics in an iso-flux upward-facing cylindrical cavity were studied by three-dimensional numerical simulation.The impacts of cavity tilt angle,wind incident angle and wind speed on convection and radiation heat transfer Nusselt number Nuc and Nur were analyzed,and the possible explanations for their impacts were presented.Results show that due to the disturbance of wind,the influence of cavity tilt angle becomes more complicated and is related to wind incident angle and wind speed.The variation of Nuc or Nur with wind incident angle is different for different cavity tilt angles.Despite of the changes of cavity tilt angle or wind incident angle,the Nuc increases with the wind speed while the Nur presents a declination with the increasing of wind speed.Hence,compared with cavity tilt angle and wind incident angle,wind speed may be the dominant factor affecting or controlling the convective and radiation heat transfer of cavity.
文摘Hong-Ou-Mandel(HOM)interference is one of the most important experimental phenomena in quantum optics.It has drawn considerable attention with respect to quantum cryptography and quantum communication because of the advent of the measurement device independent(MDI)quantum key distribution(QKD)protocol.Here,we realize HOM interference,having a visibility of approximately 38.1%,using two independent heralded single-photon sources(HSPSs).The HOM interference between two independent HSPSs is a core technology for realizing the long-distance MDI QKD protocol,the quantum coin-tossing protocol,and other quantum cryptography protocols.
