In order to overcome the low precision and weak applicability problems of the current municipal water network state simulation model, the water network structure is studied. Since the telemetry system has been applied...In order to overcome the low precision and weak applicability problems of the current municipal water network state simulation model, the water network structure is studied. Since the telemetry system has been applied increasingly in the water network, and in order to reflect the network operational condition more accurately, a new water network macroscopic model is developed by taking the auto-control adjusting valve opening state into consideration. Then for highly correlated or collinear independent variables in the model, the partial least squares (PLS) regression method provides a model solution which can distinguish between the system information and the noisy data. Finally, a hypothetical water network is introduced for validating the model. The simulation results show that the relative error is less than 5.2%, indicating that the model is efficient and feasible, and has better generalization performance.展开更多
This paper probes into the feasibility of equilibrating pressure of water distribution network through (using auto-control valves) in theory and in the economy. An optimal valve control model is designed to minimize t...This paper probes into the feasibility of equilibrating pressure of water distribution network through (using auto-control valves) in theory and in the economy. An optimal valve control model is designed to minimize the sum of squares of residual pressure in the network. Such an analog simulation has been performed on the year 2003 programming network of a certain littoral district in North China, through which this paper confirms that it is feasible to equilibrate pressure with auto-control valves in theory. The research work has brought about a discovery of applicable conditions of valves in economic feasibility, which avoids a great economic loss due to the wild use of auto-control valve. In addition, simulated annealing algorithm is applied to optimize valve settings and shown to identify global optimum or near-optimum.展开更多
废气再循环EGR(exhaust gas recirculation)阀能有效降低燃油车尾气排放,但气流扰动、摩擦力、驱动电机特性等非线性因素影响了EGR阀位置控制的性能。针对EGR阀位置伺服控制的要求,提出了一种基于扩展状态观测器、线性误差状态反馈控制...废气再循环EGR(exhaust gas recirculation)阀能有效降低燃油车尾气排放,但气流扰动、摩擦力、驱动电机特性等非线性因素影响了EGR阀位置控制的性能。针对EGR阀位置伺服控制的要求,提出了一种基于扩展状态观测器、线性误差状态反馈控制律和跟踪微分器的自抗扰控制策略,以扩展状态观测的方式估计外部扰动与系统动力学不确定性扰动,进一步以反馈控制的方式进行补偿,提高了系统对于不确定性扰动的抑制能力,实现了较好的位置伺服控制精度。最后设计了基于MATLAB的仿真平台,验证控制策略的有效性。展开更多
基金Supported by Tianjin Natural Science Foundation( No. 003611611).
文摘In order to overcome the low precision and weak applicability problems of the current municipal water network state simulation model, the water network structure is studied. Since the telemetry system has been applied increasingly in the water network, and in order to reflect the network operational condition more accurately, a new water network macroscopic model is developed by taking the auto-control adjusting valve opening state into consideration. Then for highly correlated or collinear independent variables in the model, the partial least squares (PLS) regression method provides a model solution which can distinguish between the system information and the noisy data. Finally, a hypothetical water network is introduced for validating the model. The simulation results show that the relative error is less than 5.2%, indicating that the model is efficient and feasible, and has better generalization performance.
文摘This paper probes into the feasibility of equilibrating pressure of water distribution network through (using auto-control valves) in theory and in the economy. An optimal valve control model is designed to minimize the sum of squares of residual pressure in the network. Such an analog simulation has been performed on the year 2003 programming network of a certain littoral district in North China, through which this paper confirms that it is feasible to equilibrate pressure with auto-control valves in theory. The research work has brought about a discovery of applicable conditions of valves in economic feasibility, which avoids a great economic loss due to the wild use of auto-control valve. In addition, simulated annealing algorithm is applied to optimize valve settings and shown to identify global optimum or near-optimum.
文摘废气再循环EGR(exhaust gas recirculation)阀能有效降低燃油车尾气排放,但气流扰动、摩擦力、驱动电机特性等非线性因素影响了EGR阀位置控制的性能。针对EGR阀位置伺服控制的要求,提出了一种基于扩展状态观测器、线性误差状态反馈控制律和跟踪微分器的自抗扰控制策略,以扩展状态观测的方式估计外部扰动与系统动力学不确定性扰动,进一步以反馈控制的方式进行补偿,提高了系统对于不确定性扰动的抑制能力,实现了较好的位置伺服控制精度。最后设计了基于MATLAB的仿真平台,验证控制策略的有效性。
