From the mesoscopic point of view,a definition of soft point is introduced by considering the attributes of geometric profile and mass distribution.After that,this concept is used to develop the soft matching techniqu...From the mesoscopic point of view,a definition of soft point is introduced by considering the attributes of geometric profile and mass distribution.After that,this concept is used to develop the soft matching technique to simulate the chaotic behaviors of the equations.Especially,a tennis model with deformation factor a(t)is proposed to derive a generalized Newton-Stokes equation v′(t)=λ(v T-a(t)v(t)).Furthermore,a concept of duality of deformation factor a(t)and velocity v(t)with respect to the generalized NewtonStokes equation is established.To solve this equation,two data-driven models of a(t)are provided,one is based on the concept of soft matching,while the other is by using the amplitude modulation.Finally,the related iterative algorithm is developed to simulate the motion of the falling body via the duality of a(t)and v(t).Numerical examples successfully demonstrate the phenomenon of chaos,which consists of the continual random oscillations and sudden accelerations.Moreover,the algorithm is tested by using larger coefficients corresponding to the terminal velocity and shows more satisfactory results.It may enable us to characterize the total energy of the dynamical system more accurately.展开更多
The Regional Integrated Energy System(RIES)has brought new modes of development,utilization,conversion,storage of energy.The introduction of Soft Open Point(SOP)and the application of Power to Gas(P2G)technology will ...The Regional Integrated Energy System(RIES)has brought new modes of development,utilization,conversion,storage of energy.The introduction of Soft Open Point(SOP)and the application of Power to Gas(P2G)technology will greatly deepen the coupling of the electricity-gas integrated energy system,improve the flexibility and safety of the operation of the power system,and bring a deal of benefits to the power system.On this background,an optimal dispatch model of RIES combined cold,heat,gas and electricity with SOP is proposed.Firstly,RIES architecture with SOP and P2G is designed and its mathematical model also is built.Secondly,on the basis of considering the optimal scheduling of combined cold,heat,gas and electricity,the optimal scheduling model for RIES was established.After that,the original model is transformed into a mixed-integer second-order cone programming model by using linearization and second-order cone relaxation techniques,and the CPLEX solver is invoked to solve the optimization problem.Finally,the modified IEEE 33-bus systemis used to analyze the benefits of SOP,P2G technology and lithium bromide absorption chillers in reducing systemnetwork loss and cost,as well as improving the system’s ability to absorb wind and solar and operating safety.展开更多
In the present paper, we define Dislocated Soft Metric Space and discuss about the existence and uniqueness of soft fixed point of a cyclic mapping in soft dislocated metric space. We also prove the unique soft fixed ...In the present paper, we define Dislocated Soft Metric Space and discuss about the existence and uniqueness of soft fixed point of a cyclic mapping in soft dislocated metric space. We also prove the unique soft fixed point theorems of a cyclic mapping in the context of dislocated soft metric space. Examples are given for support of the results.展开更多
Objective: To observe the therapeutic effect of acupuncture of "Xi" (Cleft) points in treatment of soft tissue injury. Methods: 335 cases of soft tissue injury patients were divided into Cleft point group (2...Objective: To observe the therapeutic effect of acupuncture of "Xi" (Cleft) points in treatment of soft tissue injury. Methods: 335 cases of soft tissue injury patients were divided into Cleft point group (264 cases) and Ashi point group (control group, 71 cases) randomly. In Cleft point group, the 16 Cleft points were used in combination with Ahshi points. In control group, only local Ahshi points were punctured. The treatment was conducted once every day, with 5 sessions being a therapeutic course. After 2 courses of treatment, the therapeutic effect was analyzed. Results: Results showed that the therapeutic effect of cleft point group was significantly better than that of control group (P<0.05), particularly in treatment of acute soft tissue. Conclusion: Cleft point acupuncture has a better therapeutic effect in treatment of soft tissue injury in comparison with Ashi point.展开更多
In the present paper,70 cases of acute sprain of soft tissue were treated withacupuncture at pressure pain points on the lateral of the second metacarpal bone.Results showedthat the cure rate was 58.6% and the total ...In the present paper,70 cases of acute sprain of soft tissue were treated withacupuncture at pressure pain points on the lateral of the second metacarpal bone.Results showedthat the cure rate was 58.6% and the total effective rate was 94.3%.Also,its mechanisms werestudied preliminarily.The present therapy is simple,convenient,easy to operate and it producesrapidly desired effects with a higher cure rate,so it is suited to be popularized clinically.展开更多
分布式可再生能源大量并网成为必然趋势,合理的设备规划可以提升配电系统运行灵活性,保证可再生能源的有效消纳。智能储能软开关(soft open points integrated with energy storage system,ESOP)具有时空双尺度运行灵活性,有利于分布式...分布式可再生能源大量并网成为必然趋势,合理的设备规划可以提升配电系统运行灵活性,保证可再生能源的有效消纳。智能储能软开关(soft open points integrated with energy storage system,ESOP)具有时空双尺度运行灵活性,有利于分布式能源并网。因此,考虑规划决策者不完全理性特点,提出一种配电网ESOP规划方法。首先,建立了含ESOP的配电网运行模型;然后,提取出多种面向高渗透率可再生能源并网下的ESOP规划经济性指标;最后,基于前景理论描述不完全理性特征,构建了配电网功率损失减少、购电成本减少、弃风弃光惩罚减少及投资成本属性的前景值模型,以年度综合前景值最大为目标构建ESOP的规划模型。通过线性化凸松弛等手段将原规划模型转化为混合整数二阶锥规划模型。改进的IEEE33节点系统与实际配电网算例结果表明,ESOP可以通过时序特性和柔性互联特性提升配电网消纳能力和运行经济性;同时,决策者对于各属性的重视程度和期望值会对规划结果产生影响。展开更多
分布式新能源出力具有波动性,且接入位置不均匀,当其规模化接入配电网后将增大发生故障的概率。在配电网发生故障时,增强并网电力电子设备的低电压穿越(low voltage ride through,LVRT)性能是保障配电网稳定运行的技术关键,已成为当前...分布式新能源出力具有波动性,且接入位置不均匀,当其规模化接入配电网后将增大发生故障的概率。在配电网发生故障时,增强并网电力电子设备的低电压穿越(low voltage ride through,LVRT)性能是保障配电网稳定运行的技术关键,已成为当前研究热点之一。以柔性互联配电网中的柔性电力电子开关(soft open point,SOP)为对象,结合配电网馈线线路阻抗特性,提出一种基于线路阻抗特性的SOP LVRT控制策略。首先,分析线路阻抗对换流器接入公共耦合点(point of common coupling,PCC)电压的影响,并推导出利用换流器注入功率抬升电压的机理;其次,提出基于馈线出线侧及换流器本地量测数据的PCC点至故障点的线路等效阻抗测量方法;然后,构建基于阻抗测量法的SOP LVRT整体策略;最后,在PSCAD仿真平台上验证所提控制策略,结果表明,在不同电压跌落范围内,所提SOP LVRT控制策略能同时补偿有功功率和无功功率,较仅采用无功补偿能更明显提升PCC电压水平。展开更多
随着分布式能源与随机负荷的大量接入,配电台区三相负荷不平衡与变压器轻重载运行问题日益突出,这将威胁台区安全可靠运行。然而,既有关于互联台区的研究鲜有兼顾三相不平衡与轻重载运行问题的综合治理。对此,该文提出一种基于四桥臂智...随着分布式能源与随机负荷的大量接入,配电台区三相负荷不平衡与变压器轻重载运行问题日益突出,这将威胁台区安全可靠运行。然而,既有关于互联台区的研究鲜有兼顾三相不平衡与轻重载运行问题的综合治理。对此,该文提出一种基于四桥臂智能软开关(four-leg soft open point,F-SOP)的柔性互联配电台区三相不平衡与轻重载综合调控策略。首先,分析了F-SOP和变压器的综合损耗特性,结果表明不平衡度和负载率均会影响设备运行效率;其次,建立三相不平衡与轻重载综合调控策略模型,设立变压器输出功率不平衡度与负载率的指标约束,以系统综合损耗最小为优化目标求解F-SOP最优调控指令。接着,针对F-SOP拓扑架构及其功率调控的需求,提出一种改进对等控制方法,进一步提高F-SOP稳定性能与动态性能,确保综合调控策略的实现。最后,通过算例分析与仿真实验验证了所提综合调控策略的有效性和可行性。展开更多
受限于车身空间容量限制和单一的工作模式,既有柴发型和储能型等移动式应急装备(mobile equipment for emergency,MEE)存在续航能力差、工能单一、闲置率高等弊端。如何改造既有装备,发掘或拓展其功能模式以提高其参与供电恢复的效果是...受限于车身空间容量限制和单一的工作模式,既有柴发型和储能型等移动式应急装备(mobile equipment for emergency,MEE)存在续航能力差、工能单一、闲置率高等弊端。如何改造既有装备,发掘或拓展其功能模式以提高其参与供电恢复的效果是当前亟待解决的问题。为此,突破传统应急装备仅能单端入网的思维,结合多端柔性互联装置与MEE的优势,提出了一种移动式储能软开关(energystored vehicle with soft open point,ESV-SOP),并详细阐述了其装备架构及工作原理,讨论了其在多种工况下的运行工作模式。同时,基于其独特的工作特性及多端口入网方式,进一步设计了面向ESV-SOP与多资源协同供电的恢复策略。首先,建立ESV-SOP多种工作模式柔性切换的数学模型及其约束。考虑灾后路网承载力变化对ESV-SOP调度的影响,提出了一种适用动态路网-配电网耦合结构的ESV-SOP移动路径表征方法。接着,在计及配电网网络重构、ESV-SOP调度、多类资源运行的基础上,综合考虑投资成本、失电经济损失、新能源消纳率等目标,设计了所提策略求解流程。最后,基于IEEE 33和IEEE 69节点系统分别验证所提ESV-SOP及其供电恢复策略的有效性与先进性。展开更多
The integration of distributed generation brings in new challenges for the operation of distribution networks,including out-of-limit voltage and power flow control.Soft open points(SOP)are new power electronic devices...The integration of distributed generation brings in new challenges for the operation of distribution networks,including out-of-limit voltage and power flow control.Soft open points(SOP)are new power electronic devices that can flexibly control active and reactive power flows.With the exception of active power output,photovoltaic(PV)devices can provide reactive power compensation through an inverter.Thus,a synergetic optimization operation method for SOP and PV in a distribution network is proposed.A synergetic optimization model was developed.The voltage deviation,network loss,and ratio of photovoltaic abandonment were selected as the objective functions.The PV model was improved by considering the three reactive power output modes of the PV inverter.Both the load fluctuation and loss of the SOP were considered.Three multi-objective optimization algorithms were used,and a compromise optimal solution was calculated.Case studies were conducted using an IEEE 33-node system.The simulation results indicated that the SOP and PVs complemented each other in terms of active power transmission and reactive power compensation.Synergetic optimization improves power control capability and flexibility,providing better power quality and PV consumption rate.展开更多
基金supported by the National Natural Science Foundation of China(Nos.12061160462,11631015)。
文摘From the mesoscopic point of view,a definition of soft point is introduced by considering the attributes of geometric profile and mass distribution.After that,this concept is used to develop the soft matching technique to simulate the chaotic behaviors of the equations.Especially,a tennis model with deformation factor a(t)is proposed to derive a generalized Newton-Stokes equation v′(t)=λ(v T-a(t)v(t)).Furthermore,a concept of duality of deformation factor a(t)and velocity v(t)with respect to the generalized NewtonStokes equation is established.To solve this equation,two data-driven models of a(t)are provided,one is based on the concept of soft matching,while the other is by using the amplitude modulation.Finally,the related iterative algorithm is developed to simulate the motion of the falling body via the duality of a(t)and v(t).Numerical examples successfully demonstrate the phenomenon of chaos,which consists of the continual random oscillations and sudden accelerations.Moreover,the algorithm is tested by using larger coefficients corresponding to the terminal velocity and shows more satisfactory results.It may enable us to characterize the total energy of the dynamical system more accurately.
基金Project Supported by National Natural Science Foundation of China(51777193).
文摘The Regional Integrated Energy System(RIES)has brought new modes of development,utilization,conversion,storage of energy.The introduction of Soft Open Point(SOP)and the application of Power to Gas(P2G)technology will greatly deepen the coupling of the electricity-gas integrated energy system,improve the flexibility and safety of the operation of the power system,and bring a deal of benefits to the power system.On this background,an optimal dispatch model of RIES combined cold,heat,gas and electricity with SOP is proposed.Firstly,RIES architecture with SOP and P2G is designed and its mathematical model also is built.Secondly,on the basis of considering the optimal scheduling of combined cold,heat,gas and electricity,the optimal scheduling model for RIES was established.After that,the original model is transformed into a mixed-integer second-order cone programming model by using linearization and second-order cone relaxation techniques,and the CPLEX solver is invoked to solve the optimization problem.Finally,the modified IEEE 33-bus systemis used to analyze the benefits of SOP,P2G technology and lithium bromide absorption chillers in reducing systemnetwork loss and cost,as well as improving the system’s ability to absorb wind and solar and operating safety.
文摘In the present paper, we define Dislocated Soft Metric Space and discuss about the existence and uniqueness of soft fixed point of a cyclic mapping in soft dislocated metric space. We also prove the unique soft fixed point theorems of a cyclic mapping in the context of dislocated soft metric space. Examples are given for support of the results.
文摘Objective: To observe the therapeutic effect of acupuncture of "Xi" (Cleft) points in treatment of soft tissue injury. Methods: 335 cases of soft tissue injury patients were divided into Cleft point group (264 cases) and Ashi point group (control group, 71 cases) randomly. In Cleft point group, the 16 Cleft points were used in combination with Ahshi points. In control group, only local Ahshi points were punctured. The treatment was conducted once every day, with 5 sessions being a therapeutic course. After 2 courses of treatment, the therapeutic effect was analyzed. Results: Results showed that the therapeutic effect of cleft point group was significantly better than that of control group (P<0.05), particularly in treatment of acute soft tissue. Conclusion: Cleft point acupuncture has a better therapeutic effect in treatment of soft tissue injury in comparison with Ashi point.
文摘In the present paper,70 cases of acute sprain of soft tissue were treated withacupuncture at pressure pain points on the lateral of the second metacarpal bone.Results showedthat the cure rate was 58.6% and the total effective rate was 94.3%.Also,its mechanisms werestudied preliminarily.The present therapy is simple,convenient,easy to operate and it producesrapidly desired effects with a higher cure rate,so it is suited to be popularized clinically.
文摘分布式可再生能源大量并网成为必然趋势,合理的设备规划可以提升配电系统运行灵活性,保证可再生能源的有效消纳。智能储能软开关(soft open points integrated with energy storage system,ESOP)具有时空双尺度运行灵活性,有利于分布式能源并网。因此,考虑规划决策者不完全理性特点,提出一种配电网ESOP规划方法。首先,建立了含ESOP的配电网运行模型;然后,提取出多种面向高渗透率可再生能源并网下的ESOP规划经济性指标;最后,基于前景理论描述不完全理性特征,构建了配电网功率损失减少、购电成本减少、弃风弃光惩罚减少及投资成本属性的前景值模型,以年度综合前景值最大为目标构建ESOP的规划模型。通过线性化凸松弛等手段将原规划模型转化为混合整数二阶锥规划模型。改进的IEEE33节点系统与实际配电网算例结果表明,ESOP可以通过时序特性和柔性互联特性提升配电网消纳能力和运行经济性;同时,决策者对于各属性的重视程度和期望值会对规划结果产生影响。
文摘分布式新能源出力具有波动性,且接入位置不均匀,当其规模化接入配电网后将增大发生故障的概率。在配电网发生故障时,增强并网电力电子设备的低电压穿越(low voltage ride through,LVRT)性能是保障配电网稳定运行的技术关键,已成为当前研究热点之一。以柔性互联配电网中的柔性电力电子开关(soft open point,SOP)为对象,结合配电网馈线线路阻抗特性,提出一种基于线路阻抗特性的SOP LVRT控制策略。首先,分析线路阻抗对换流器接入公共耦合点(point of common coupling,PCC)电压的影响,并推导出利用换流器注入功率抬升电压的机理;其次,提出基于馈线出线侧及换流器本地量测数据的PCC点至故障点的线路等效阻抗测量方法;然后,构建基于阻抗测量法的SOP LVRT整体策略;最后,在PSCAD仿真平台上验证所提控制策略,结果表明,在不同电压跌落范围内,所提SOP LVRT控制策略能同时补偿有功功率和无功功率,较仅采用无功补偿能更明显提升PCC电压水平。
文摘随着分布式能源与随机负荷的大量接入,配电台区三相负荷不平衡与变压器轻重载运行问题日益突出,这将威胁台区安全可靠运行。然而,既有关于互联台区的研究鲜有兼顾三相不平衡与轻重载运行问题的综合治理。对此,该文提出一种基于四桥臂智能软开关(four-leg soft open point,F-SOP)的柔性互联配电台区三相不平衡与轻重载综合调控策略。首先,分析了F-SOP和变压器的综合损耗特性,结果表明不平衡度和负载率均会影响设备运行效率;其次,建立三相不平衡与轻重载综合调控策略模型,设立变压器输出功率不平衡度与负载率的指标约束,以系统综合损耗最小为优化目标求解F-SOP最优调控指令。接着,针对F-SOP拓扑架构及其功率调控的需求,提出一种改进对等控制方法,进一步提高F-SOP稳定性能与动态性能,确保综合调控策略的实现。最后,通过算例分析与仿真实验验证了所提综合调控策略的有效性和可行性。
文摘受限于车身空间容量限制和单一的工作模式,既有柴发型和储能型等移动式应急装备(mobile equipment for emergency,MEE)存在续航能力差、工能单一、闲置率高等弊端。如何改造既有装备,发掘或拓展其功能模式以提高其参与供电恢复的效果是当前亟待解决的问题。为此,突破传统应急装备仅能单端入网的思维,结合多端柔性互联装置与MEE的优势,提出了一种移动式储能软开关(energystored vehicle with soft open point,ESV-SOP),并详细阐述了其装备架构及工作原理,讨论了其在多种工况下的运行工作模式。同时,基于其独特的工作特性及多端口入网方式,进一步设计了面向ESV-SOP与多资源协同供电的恢复策略。首先,建立ESV-SOP多种工作模式柔性切换的数学模型及其约束。考虑灾后路网承载力变化对ESV-SOP调度的影响,提出了一种适用动态路网-配电网耦合结构的ESV-SOP移动路径表征方法。接着,在计及配电网网络重构、ESV-SOP调度、多类资源运行的基础上,综合考虑投资成本、失电经济损失、新能源消纳率等目标,设计了所提策略求解流程。最后,基于IEEE 33和IEEE 69节点系统分别验证所提ESV-SOP及其供电恢复策略的有效性与先进性。
基金supported by the Science and Technology Project of SGCC(kj2022-075).
文摘The integration of distributed generation brings in new challenges for the operation of distribution networks,including out-of-limit voltage and power flow control.Soft open points(SOP)are new power electronic devices that can flexibly control active and reactive power flows.With the exception of active power output,photovoltaic(PV)devices can provide reactive power compensation through an inverter.Thus,a synergetic optimization operation method for SOP and PV in a distribution network is proposed.A synergetic optimization model was developed.The voltage deviation,network loss,and ratio of photovoltaic abandonment were selected as the objective functions.The PV model was improved by considering the three reactive power output modes of the PV inverter.Both the load fluctuation and loss of the SOP were considered.Three multi-objective optimization algorithms were used,and a compromise optimal solution was calculated.Case studies were conducted using an IEEE 33-node system.The simulation results indicated that the SOP and PVs complemented each other in terms of active power transmission and reactive power compensation.Synergetic optimization improves power control capability and flexibility,providing better power quality and PV consumption rate.