Distributed generations(DGs)are main components for active distribution networks(ADNs).Owing to the large number of DGs integrated into distribution levels,it will be essential to schedule active and reactive power re...Distributed generations(DGs)are main components for active distribution networks(ADNs).Owing to the large number of DGs integrated into distribution levels,it will be essential to schedule active and reactive power resources in ADNs.Generally,energy and reactive power scheduling problems are separately managed in ADNs.However,the separate scheduling cannot attain a global optimum scheme in the operation of ADNs.In this paper,a probabilistic simultaneous active/reactive scheduling framework is presented for ADNs.In order to handle the uncertainties of power generations of renewable-based DGs and upstream grid prices in an efficient framework,a stochastic programming technique is proposed.The stochastic programming can help distribution system operators(DSOs)make operation decisions in front of existing uncertainties.The proposed coordinated model considers the minimization of the energy and reactive power costs of all distributed resources along with the upstream grid.Meanwhile,a new payment index as loss profit value for DG units is introduced and embedded in the model.Numerical results based on the 22-bus and IEEE33-bus ADNs validate the effectiveness of the proposed method.The obtained results verify that through the proposed stochastic-based power management system,the DSO can effectively schedule all DGs along with its economic targets while considering severe uncertainties.展开更多
In traditional power systems,besides the conventional power plants that provide the necessary reactive power in transmission system,the shunt capacitors along with the tap changers of transformers are also employed in...In traditional power systems,besides the conventional power plants that provide the necessary reactive power in transmission system,the shunt capacitors along with the tap changers of transformers are also employed in distribution networks.In future years,because of the high number of distributed resources integrated into the distribution networks,it will be essential to schedule complete active-reactive power at distribution level.In this research work,an economic framework based on the active-reactive power bids has been developed for complete active-reactive power dispatch scheduling of smart distribution networks.The economical complete active-reactive power scheduling approach suggested in this study motivates distributed energy resources(DERs)to cooperate in both active power markets and the Volt/Var control scheme.To this end,using DER’s reactive power capability,a generic framework of reactive power offers for DERs is extracted.A 22-bus distribution test system is implemented to verify the impressiveness of the suggested active-reactive power scheduling approach.展开更多
Unified power quality conditioner(UPQC)holds the capability of solving power quality problems,especially shows good performance in the voltage sag compensation. In this paper, a compensation strategy based on simultan...Unified power quality conditioner(UPQC)holds the capability of solving power quality problems,especially shows good performance in the voltage sag compensation. In this paper, a compensation strategy based on simultaneous reactive power injection for UPQC(namely UPQC-SRI) is proposed to address the issue of voltage sag. The proposed UPQC-SRI determines the injection angle of compensation voltage with consideration of optimal configuration of UPQC current-carrying.Moreover, the compensation strategy also considers the current-carrying limit of UPQC, and then the zero active power injection region of UPQC-SRI(also called UPQCSRI region) is obtained. Under the conditions which exceed the UPQC-SRI region, the limit value of shunt current is determined by this proposed strategy. Finally, the proposed strategy and the corresponding algorithm are verified under the PSCAD/EMTDC platform. The result indicates the proposed UPQC-SRI strategy in this paper can provide more persistent voltage sag compensation than the previous strategies for the sensitive load.展开更多
文摘Distributed generations(DGs)are main components for active distribution networks(ADNs).Owing to the large number of DGs integrated into distribution levels,it will be essential to schedule active and reactive power resources in ADNs.Generally,energy and reactive power scheduling problems are separately managed in ADNs.However,the separate scheduling cannot attain a global optimum scheme in the operation of ADNs.In this paper,a probabilistic simultaneous active/reactive scheduling framework is presented for ADNs.In order to handle the uncertainties of power generations of renewable-based DGs and upstream grid prices in an efficient framework,a stochastic programming technique is proposed.The stochastic programming can help distribution system operators(DSOs)make operation decisions in front of existing uncertainties.The proposed coordinated model considers the minimization of the energy and reactive power costs of all distributed resources along with the upstream grid.Meanwhile,a new payment index as loss profit value for DG units is introduced and embedded in the model.Numerical results based on the 22-bus and IEEE33-bus ADNs validate the effectiveness of the proposed method.The obtained results verify that through the proposed stochastic-based power management system,the DSO can effectively schedule all DGs along with its economic targets while considering severe uncertainties.
文摘In traditional power systems,besides the conventional power plants that provide the necessary reactive power in transmission system,the shunt capacitors along with the tap changers of transformers are also employed in distribution networks.In future years,because of the high number of distributed resources integrated into the distribution networks,it will be essential to schedule complete active-reactive power at distribution level.In this research work,an economic framework based on the active-reactive power bids has been developed for complete active-reactive power dispatch scheduling of smart distribution networks.The economical complete active-reactive power scheduling approach suggested in this study motivates distributed energy resources(DERs)to cooperate in both active power markets and the Volt/Var control scheme.To this end,using DER’s reactive power capability,a generic framework of reactive power offers for DERs is extracted.A 22-bus distribution test system is implemented to verify the impressiveness of the suggested active-reactive power scheduling approach.
基金supported by the twelfth five-year National Mega-projects of Science and Technology (2011BAA01B03)
文摘Unified power quality conditioner(UPQC)holds the capability of solving power quality problems,especially shows good performance in the voltage sag compensation. In this paper, a compensation strategy based on simultaneous reactive power injection for UPQC(namely UPQC-SRI) is proposed to address the issue of voltage sag. The proposed UPQC-SRI determines the injection angle of compensation voltage with consideration of optimal configuration of UPQC current-carrying.Moreover, the compensation strategy also considers the current-carrying limit of UPQC, and then the zero active power injection region of UPQC-SRI(also called UPQCSRI region) is obtained. Under the conditions which exceed the UPQC-SRI region, the limit value of shunt current is determined by this proposed strategy. Finally, the proposed strategy and the corresponding algorithm are verified under the PSCAD/EMTDC platform. The result indicates the proposed UPQC-SRI strategy in this paper can provide more persistent voltage sag compensation than the previous strategies for the sensitive load.
