This paper proposes a new method for service restoration of distribution network with the support of transportable power sources(TPSs)and repair crews(RCs).Firstly,a coupling model of distribution networks and vehicle...This paper proposes a new method for service restoration of distribution network with the support of transportable power sources(TPSs)and repair crews(RCs).Firstly,a coupling model of distribution networks and vehicle routing of TPSs and RCs is proposed,where the TPSs serve as emergency power supply sources,and the RCs are used to repair the faulted lines.Considering the uncertainty of traffic congestion,the probability distribution of the travel time spent on each road is derived based on the Nesterov user equilibrium model,and a two-stage stochastic program is formulated to determine the optimal routings of TPSs and RCs.To efficiently solve the proposed stochastic mixed-integer linear program(MILP),a two-phase scenario reduction method is then developed to scale down the problem size,and an adaptive progressive hedging algorithm is used for an efficient solution.The effectiveness of the proposed methods and algorithms has been illustrated in a modified IEEE 33-bus system.展开更多
The rapid development of electric vehicles(EVs)is strengthening the bi-directional interactions between electric power networks(EPNs)and transportation networks(TNs)while providing opportunities to enhance the resilie...The rapid development of electric vehicles(EVs)is strengthening the bi-directional interactions between electric power networks(EPNs)and transportation networks(TNs)while providing opportunities to enhance the resilience of power systems towards extreme events.To quantify the temporal and spatial flexibility of EVs for charging and discharging,a novel dynamic traffic assignment(DTA)problem is proposed.The DTA problem is based on a link transmission model(LTM)with extended charging links,depicting the interaction between EVs and power systems.It models the charging rates as continuous variables by an energy boundary model.To consider the evacuation requirements of TNs and the uncertainties of traffic conditions,the DTA problem is extended to a two-stage distributionally robust version.It is further incorporated into a two-stage distributionally robust unit commitment problem to balance the enhancement of EPNs and the performance of TNs.The problem is reformulated into a mixed-integer linear programming problem and solved by off-the-shelf commercial solvers.Case studies are performed on two test networks.The effectiveness is verified by the numerical results,e.g.,reducing the load shedding amount without increasing the unmet traffic demand.展开更多
This paper describes the planned power transmission from west to east through three channels. It presents the main characteristics of these three channels and the problems need to be solved.
随着电力系统对通信技术依赖性增强,传统通信框架已无法满足其高效率和高安全性需求。光传送网(Optical Transport Network,OTN)技术凭借其高带宽、高可靠性以及优异的网络管理能力,成为现代电力系统通信的理想选择。文章深入探讨OTN技...随着电力系统对通信技术依赖性增强,传统通信框架已无法满足其高效率和高安全性需求。光传送网(Optical Transport Network,OTN)技术凭借其高带宽、高可靠性以及优异的网络管理能力,成为现代电力系统通信的理想选择。文章深入探讨OTN技术在电力系统通信中的应用,包括提高数据传输速率、增强网络可靠性与故障恢复能力、优化网络资源分配,并通过冗余设计和灾难恢复策略增强系统的整体稳定性。最后,进行技术应用测试,验证OTN技术在实际电力系统中的应用效果和潜在价值。展开更多
Wave reflection and transmission in a beam containing a semi-infinite crack are studied analytically based on Timoshenko beam theory., Two kinds of crack surface conditions： non-contact （open） and fully contact （c...Wave reflection and transmission in a beam containing a semi-infinite crack are studied analytically based on Timoshenko beam theory., Two kinds of crack surface conditions： non-contact （open） and fully contact （closed） cracks, are considered respectively for an isotropic beam. The analytical solution of reflection and transmission coefficients for a semi-infinite crack is obtained. The power reflection and transmission ratios depend on both the frequency and the position of the crack. Numerical results show the conservation of power transport. The transmitted energy among various wave modes is also investigated. A finite element method is used to verify the validity of the analytical results.展开更多
在电力通信传输领域,网络的宽带容量、延迟表现、安全性是衡量其性能的关键指标。光传送网(Optical Transport Network,OTN)技术具有独特的网络层次结构和高效的数据传输能力,能够支持高带宽数据传输,利用有效的波分复用(Wavelength Div...在电力通信传输领域,网络的宽带容量、延迟表现、安全性是衡量其性能的关键指标。光传送网(Optical Transport Network,OTN)技术具有独特的网络层次结构和高效的数据传输能力,能够支持高带宽数据传输,利用有效的波分复用(Wavelength Division Multiplexing,WDM)和光交换技术,降低网络延迟和提升数据传输的安全性。文章设计了一种基于OTN技术的电力通信传输网络优化系统,分析系统设计的总体框架、关键技术的选择和应用、设计实现的具体步骤,并全面探讨如何利用OTN技术提高电力通信网络的宽带、降低网络延迟以及提升增强网络安全性。展开更多
Titanylphthalocyanine （TiOPc） as hole transporting material （HTM） was successfully synthesized by a simple process with low cost. Perovskite solar cells using the TiOPc as HTM were fabricated and characterized. Ti...Titanylphthalocyanine （TiOPc） as hole transporting material （HTM） was successfully synthesized by a simple process with low cost. Perovskite solar cells using the TiOPc as HTM were fabricated and characterized. TiOPc as HTM plays an important role in increasing the power conversion efficiency （PCE） by minimizing recombi- nation losses at the perovskite/Au interface because TiOPc as HTM can extract photogenerated holes from the perovskite and then transport quickly these charges to the back metal electrode. In the research, the β-TiOPc gives a higher PCE than α-TiOPc for the devices due to sufficient transfer dynamics, The β-TiOPc was applied in perovskite solar cells without clopping to afford an impressive PCE of 5.05% under AM 1.5G illumination at the thickness of 40 nm which is competitive with spiro-OMeTAD at the same condition. The present work suggests a guideline for optimizing the photovoltaic properties ofperovskite solar cells using the TiOPc as the HTM.展开更多
基金supported by National Natural Science Foundation of China(No.72171026).
文摘This paper proposes a new method for service restoration of distribution network with the support of transportable power sources(TPSs)and repair crews(RCs).Firstly,a coupling model of distribution networks and vehicle routing of TPSs and RCs is proposed,where the TPSs serve as emergency power supply sources,and the RCs are used to repair the faulted lines.Considering the uncertainty of traffic congestion,the probability distribution of the travel time spent on each road is derived based on the Nesterov user equilibrium model,and a two-stage stochastic program is formulated to determine the optimal routings of TPSs and RCs.To efficiently solve the proposed stochastic mixed-integer linear program(MILP),a two-phase scenario reduction method is then developed to scale down the problem size,and an adaptive progressive hedging algorithm is used for an efficient solution.The effectiveness of the proposed methods and algorithms has been illustrated in a modified IEEE 33-bus system.
文摘The rapid development of electric vehicles(EVs)is strengthening the bi-directional interactions between electric power networks(EPNs)and transportation networks(TNs)while providing opportunities to enhance the resilience of power systems towards extreme events.To quantify the temporal and spatial flexibility of EVs for charging and discharging,a novel dynamic traffic assignment(DTA)problem is proposed.The DTA problem is based on a link transmission model(LTM)with extended charging links,depicting the interaction between EVs and power systems.It models the charging rates as continuous variables by an energy boundary model.To consider the evacuation requirements of TNs and the uncertainties of traffic conditions,the DTA problem is extended to a two-stage distributionally robust version.It is further incorporated into a two-stage distributionally robust unit commitment problem to balance the enhancement of EPNs and the performance of TNs.The problem is reformulated into a mixed-integer linear programming problem and solved by off-the-shelf commercial solvers.Case studies are performed on two test networks.The effectiveness is verified by the numerical results,e.g.,reducing the load shedding amount without increasing the unmet traffic demand.
文摘This paper describes the planned power transmission from west to east through three channels. It presents the main characteristics of these three channels and the problems need to be solved.
文摘随着电力系统对通信技术依赖性增强,传统通信框架已无法满足其高效率和高安全性需求。光传送网(Optical Transport Network,OTN)技术凭借其高带宽、高可靠性以及优异的网络管理能力,成为现代电力系统通信的理想选择。文章深入探讨OTN技术在电力系统通信中的应用,包括提高数据传输速率、增强网络可靠性与故障恢复能力、优化网络资源分配,并通过冗余设计和灾难恢复策略增强系统的整体稳定性。最后,进行技术应用测试,验证OTN技术在实际电力系统中的应用效果和潜在价值。
基金the National Natural Science Foundation of China(Nos.50478037 and 10572058)the Research Foundation for the Doctoral Program of Higher Education(No.20050287016).
文摘Wave reflection and transmission in a beam containing a semi-infinite crack are studied analytically based on Timoshenko beam theory., Two kinds of crack surface conditions： non-contact （open） and fully contact （closed） cracks, are considered respectively for an isotropic beam. The analytical solution of reflection and transmission coefficients for a semi-infinite crack is obtained. The power reflection and transmission ratios depend on both the frequency and the position of the crack. Numerical results show the conservation of power transport. The transmitted energy among various wave modes is also investigated. A finite element method is used to verify the validity of the analytical results.
文摘在电力通信传输领域,网络的宽带容量、延迟表现、安全性是衡量其性能的关键指标。光传送网(Optical Transport Network,OTN)技术具有独特的网络层次结构和高效的数据传输能力,能够支持高带宽数据传输,利用有效的波分复用(Wavelength Division Multiplexing,WDM)和光交换技术,降低网络延迟和提升数据传输的安全性。文章设计了一种基于OTN技术的电力通信传输网络优化系统,分析系统设计的总体框架、关键技术的选择和应用、设计实现的具体步骤,并全面探讨如何利用OTN技术提高电力通信网络的宽带、降低网络延迟以及提升增强网络安全性。
基金supported by the National Nature Science Foundation of China (NO.21206110)Tianjin Science and Technology Support Plan Key Projects (NO.13ZCZDGX00900)
文摘Titanylphthalocyanine （TiOPc） as hole transporting material （HTM） was successfully synthesized by a simple process with low cost. Perovskite solar cells using the TiOPc as HTM were fabricated and characterized. TiOPc as HTM plays an important role in increasing the power conversion efficiency （PCE） by minimizing recombi- nation losses at the perovskite/Au interface because TiOPc as HTM can extract photogenerated holes from the perovskite and then transport quickly these charges to the back metal electrode. In the research, the β-TiOPc gives a higher PCE than α-TiOPc for the devices due to sufficient transfer dynamics, The β-TiOPc was applied in perovskite solar cells without clopping to afford an impressive PCE of 5.05% under AM 1.5G illumination at the thickness of 40 nm which is competitive with spiro-OMeTAD at the same condition. The present work suggests a guideline for optimizing the photovoltaic properties ofperovskite solar cells using the TiOPc as the HTM.
