The optimal operation of water distribution networks under local pipe failures, such as water main breaks, was proposed. Based on a hydraulic analysis and a simulation of water distribution networks, a macroscopic mod...The optimal operation of water distribution networks under local pipe failures, such as water main breaks, was proposed. Based on a hydraulic analysis and a simulation of water distribution networks, a macroscopic model for a network under a local pipe failure was established by the statistical regression. After the operation objectives under a local pipe failure were determined, the optimal operation model was developed and solved by the genetic algorithm. The program was developed and examined by a city distribution network. The optimal operation alternative shows that the electricity cost is saved approximately 11%, the income of the water corporation is increased approximately 5%, and the pressure in the water distribution network is distributed evenly to ensure the network safe operation. Therefore, the proposed method for optimal operation under local pipe failure is feasible and cost-effective.展开更多
This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously a...This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously and to improve power system's accountability and system performance parameters. Due to finding solution which is closer to realistic characteristics, load forecasting, market price errors and the uncertainties related to the variable output power of wind based DG units are put in consideration. This work employs NSGA-II accompanied by the fuzzy set theory to solve the aforementioned multi-objective problem. The proposed scheme finally leads to a solution with a minimum voltage deviation, a maximum voltage stability, lower amount of pollutant and lower cost. The cost includes the installation costs of new equipment, reconfiguration costs, power loss cost, reliability cost, cost of energy purchased from power market, upgrade costs of lines and operation and maintenance costs of DGs. Therefore, the proposed methodology improves power quality, reliability and security in lower costs besides its preserve, with the operational indices of power distribution networks in acceptable level. To validate the proposed methodology's usefulness, it was applied on the IEEE 33-bus distribution system then the outcomes were compared with initial configuration.展开更多
针对持续扰动下的分布式状态耦合非线性系统,提出一种新的多耦合分布式经济模型预测控制(Economic model predictive control,EMPC)策略.由于耦合非线性系统的经济性能函数的非凸性和非正定性,首先引入关于经济最优平衡点的正定辅助函...针对持续扰动下的分布式状态耦合非线性系统,提出一种新的多耦合分布式经济模型预测控制(Economic model predictive control,EMPC)策略.由于耦合非线性系统的经济性能函数的非凸性和非正定性,首先引入关于经济最优平衡点的正定辅助函数和相应的辅助优化问题.接着,利用辅助函数的最优值函数构造原始分布式EMPC的一类隐式收缩约束.然后,建立状态耦合分布式EMPC的递推可行性和闭环系统关于最优经济平衡点的输入到状态稳定性(Input-to-state stability,ISS).最后,以耦合的四个连续搅拌釜反应器(Continuous stirred tank reactors,CSTRs)为例,验证本文所提策略的有效性.展开更多
基金Project(50278062) supported by the National Natural Science Foundation of ChinaProject(003611611)supported by the Natural Science Foundation of Tianjin, China
文摘The optimal operation of water distribution networks under local pipe failures, such as water main breaks, was proposed. Based on a hydraulic analysis and a simulation of water distribution networks, a macroscopic model for a network under a local pipe failure was established by the statistical regression. After the operation objectives under a local pipe failure were determined, the optimal operation model was developed and solved by the genetic algorithm. The program was developed and examined by a city distribution network. The optimal operation alternative shows that the electricity cost is saved approximately 11%, the income of the water corporation is increased approximately 5%, and the pressure in the water distribution network is distributed evenly to ensure the network safe operation. Therefore, the proposed method for optimal operation under local pipe failure is feasible and cost-effective.
文摘This research develops a comprehensive method to solve a combinatorial problem consisting of distribution system reconfiguration, capacitor allocation, and renewable energy resources sizing and siting simultaneously and to improve power system's accountability and system performance parameters. Due to finding solution which is closer to realistic characteristics, load forecasting, market price errors and the uncertainties related to the variable output power of wind based DG units are put in consideration. This work employs NSGA-II accompanied by the fuzzy set theory to solve the aforementioned multi-objective problem. The proposed scheme finally leads to a solution with a minimum voltage deviation, a maximum voltage stability, lower amount of pollutant and lower cost. The cost includes the installation costs of new equipment, reconfiguration costs, power loss cost, reliability cost, cost of energy purchased from power market, upgrade costs of lines and operation and maintenance costs of DGs. Therefore, the proposed methodology improves power quality, reliability and security in lower costs besides its preserve, with the operational indices of power distribution networks in acceptable level. To validate the proposed methodology's usefulness, it was applied on the IEEE 33-bus distribution system then the outcomes were compared with initial configuration.
文摘针对持续扰动下的分布式状态耦合非线性系统,提出一种新的多耦合分布式经济模型预测控制(Economic model predictive control,EMPC)策略.由于耦合非线性系统的经济性能函数的非凸性和非正定性,首先引入关于经济最优平衡点的正定辅助函数和相应的辅助优化问题.接着,利用辅助函数的最优值函数构造原始分布式EMPC的一类隐式收缩约束.然后,建立状态耦合分布式EMPC的递推可行性和闭环系统关于最优经济平衡点的输入到状态稳定性(Input-to-state stability,ISS).最后,以耦合的四个连续搅拌釜反应器(Continuous stirred tank reactors,CSTRs)为例,验证本文所提策略的有效性.
