In this paper,two new models suitable for power system stability analysis with considering time delays are derived.They are constraint time-delayed ordinary differential equation model(CTODE model) and constraint time...In this paper,two new models suitable for power system stability analysis with considering time delays are derived.They are constraint time-delayed ordinary differential equation model(CTODE model) and constraint time-delayed differential algebraic equation model(CTDAE model).In these two models,dimension of the time-delayed equation is significantly reduced so as to speed up the calculation efficiency.Detail derivations to their nonlinear and incremental linear forms are given.And,some of their good features are discussed.Finally,a typical time-delayed system and single-machine-infinite-bus system are selected to validate the new models through Lyapunov-Krasovskii criterion and eigenvalue locus tracing procedure.It reveals that some unnecessary calculations in the algorithm can be avoided to achieve higher efficiency based on new models.The new models and new criterion given in this paper are helpful to design wide area protectors for bulk power systems.展开更多
Environmentally clean photovoltaic(PV)generation has found wider application,but the power f luctuation generated from PV can negatively impact the operation of power system.A properly designed energy storage system(E...Environmentally clean photovoltaic(PV)generation has found wider application,but the power f luctuation generated from PV can negatively impact the operation of power system.A properly designed energy storage system(ESS)can stabilize power system by absorbing and injecting instantaneous power.Suitable control strategy of ESS is studied in order to accommodate the power f luctuation.It adopts negative feedback which considers the relationship between real power and voltage in the distribution network because resistor is comparable to reactance of the lines in the distribution network.A universal model of ESS is established,the characteristic parameters such as time-delay of system response,limitation of charging and discharging and restraint of energy storage capacity are taken into account.The validity of the proposed model is verif ied by user-def ined modules in power system analysis software package(PSASP).The operation of PV generation at Wuhan Railway Station in both grid-connected mode and island mode at Wuhan Railway Station is analyzed in detail.The performances of the local distribution network with PV under different weather conditions are summarized,and the key parameter of ESS suitable for PV generation at Wuhan Railway Station is also recommended.展开更多
基金supported by Special Fund of the National Basic Research Program of China("973"Program)(Grant No.2009CB219701)National Natural Science Foundation of China(Grant No.51277128)State Grid Corporation of China(Grant No.SGCC-MPLG028-2012)
文摘In this paper,two new models suitable for power system stability analysis with considering time delays are derived.They are constraint time-delayed ordinary differential equation model(CTODE model) and constraint time-delayed differential algebraic equation model(CTDAE model).In these two models,dimension of the time-delayed equation is significantly reduced so as to speed up the calculation efficiency.Detail derivations to their nonlinear and incremental linear forms are given.And,some of their good features are discussed.Finally,a typical time-delayed system and single-machine-infinite-bus system are selected to validate the new models through Lyapunov-Krasovskii criterion and eigenvalue locus tracing procedure.It reveals that some unnecessary calculations in the algorithm can be avoided to achieve higher efficiency based on new models.The new models and new criterion given in this paper are helpful to design wide area protectors for bulk power systems.
基金Key Project of National Natural Science Foundation China(50837003)The National Basic Research Program(973 Program)(2009CB219702)
文摘Environmentally clean photovoltaic(PV)generation has found wider application,but the power f luctuation generated from PV can negatively impact the operation of power system.A properly designed energy storage system(ESS)can stabilize power system by absorbing and injecting instantaneous power.Suitable control strategy of ESS is studied in order to accommodate the power f luctuation.It adopts negative feedback which considers the relationship between real power and voltage in the distribution network because resistor is comparable to reactance of the lines in the distribution network.A universal model of ESS is established,the characteristic parameters such as time-delay of system response,limitation of charging and discharging and restraint of energy storage capacity are taken into account.The validity of the proposed model is verif ied by user-def ined modules in power system analysis software package(PSASP).The operation of PV generation at Wuhan Railway Station in both grid-connected mode and island mode at Wuhan Railway Station is analyzed in detail.The performances of the local distribution network with PV under different weather conditions are summarized,and the key parameter of ESS suitable for PV generation at Wuhan Railway Station is also recommended.
