为分析智能软开关(soft open point,SOP)连续调节能力对柔性配电网(flexible distribution network,FDN)风险的影响。首先,实现基于三点估计的FDN风险评估方法;采用三点估计法结合交直流交替迭代法和Gram-Charlier级数展开法进行FDN概...为分析智能软开关(soft open point,SOP)连续调节能力对柔性配电网(flexible distribution network,FDN)风险的影响。首先,实现基于三点估计的FDN风险评估方法;采用三点估计法结合交直流交替迭代法和Gram-Charlier级数展开法进行FDN概率潮流计算,获得节点电压与支路有功功率的概率密度函数,使用越限偏移量结合风险偏好型效用函数构建严重度函数,根据风险评估理论建立并计算风险评估指标。其次,在此基础上,提出一种计及SOP参数优化的FDN风险评估方法;以系统总风险最低为目标,建立计及SOP参数优化的FDN风险评估模型,采用粒子群优化算法结合基于三点估计的FDN风险评估方法对其进行求解,用得到的结果去配置SOP,并对此FDN进行风险评估。以3个IEEE 33节点网络通过三端口SOP互联形成的FDN为例,验证了所提风险评估方法的有效性,分析了SOP连续调节能力以及不同接入位置对FDN风险的影响。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
Objective To observe the anti-CVB3 （ Coxsackievirus B3 ） effect of sophocarpine （SC） extracted from Sophora flavescens, a traditional Chinese herb in vitro. Methods Cardiomyocytes from the neonatal rat were cultur...Objective To observe the anti-CVB3 （ Coxsackievirus B3 ） effect of sophocarpine （SC） extracted from Sophora flavescens, a traditional Chinese herb in vitro. Methods Cardiomyocytes from the neonatal rat were cultured to establish the viral myocarditis model The cells were divided into four groups： infected group （ infected by CVB3 ） , SC treated group （ added SC 100 μg/mL after viral infection ）, SC control group （ added SC 100 μg/mL only）, and normal control group. The cytopathic effect （CPE） and the beating frequency of the myocardial cells were observed and the LDH levels in the supernatant were measured at day 2,3, and 5. The cultured myocytes were added different concentrations of SC （ 12. 5 -400 μg/mL ） after infection with CVB3, the CPE was observed and the concentrations of LDH were measured and compared at day 2, 3, and 5. Results In the SC treated group （ 100 μg/mL ） , the cytopathic effect was lighter and the LDH level was lower than the infected group. SC in a concentration of 12. 5 - 300 μg/mL could relieve the CPE and lower the LDH level, while in a higher concentration （400 μ/m ） , it exacerbated the CPE caused by the virus, and the LDH levels were higher than the infected cells. Conclusion SC in certain concentration could protect the cultured rat cardiomyocytes from CVB3 infection.展开更多
文摘为分析智能软开关(soft open point,SOP)连续调节能力对柔性配电网(flexible distribution network,FDN)风险的影响。首先,实现基于三点估计的FDN风险评估方法;采用三点估计法结合交直流交替迭代法和Gram-Charlier级数展开法进行FDN概率潮流计算,获得节点电压与支路有功功率的概率密度函数,使用越限偏移量结合风险偏好型效用函数构建严重度函数,根据风险评估理论建立并计算风险评估指标。其次,在此基础上,提出一种计及SOP参数优化的FDN风险评估方法;以系统总风险最低为目标,建立计及SOP参数优化的FDN风险评估模型,采用粒子群优化算法结合基于三点估计的FDN风险评估方法对其进行求解,用得到的结果去配置SOP,并对此FDN进行风险评估。以3个IEEE 33节点网络通过三端口SOP互联形成的FDN为例,验证了所提风险评估方法的有效性,分析了SOP连续调节能力以及不同接入位置对FDN风险的影响。
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.
文摘Objective To observe the anti-CVB3 （ Coxsackievirus B3 ） effect of sophocarpine （SC） extracted from Sophora flavescens, a traditional Chinese herb in vitro. Methods Cardiomyocytes from the neonatal rat were cultured to establish the viral myocarditis model The cells were divided into four groups： infected group （ infected by CVB3 ） , SC treated group （ added SC 100 μg/mL after viral infection ）, SC control group （ added SC 100 μg/mL only）, and normal control group. The cytopathic effect （CPE） and the beating frequency of the myocardial cells were observed and the LDH levels in the supernatant were measured at day 2,3, and 5. The cultured myocytes were added different concentrations of SC （ 12. 5 -400 μg/mL ） after infection with CVB3, the CPE was observed and the concentrations of LDH were measured and compared at day 2, 3, and 5. Results In the SC treated group （ 100 μg/mL ） , the cytopathic effect was lighter and the LDH level was lower than the infected group. SC in a concentration of 12. 5 - 300 μg/mL could relieve the CPE and lower the LDH level, while in a higher concentration （400 μ/m ） , it exacerbated the CPE caused by the virus, and the LDH levels were higher than the infected cells. Conclusion SC in certain concentration could protect the cultured rat cardiomyocytes from CVB3 infection.
