随着多能源不断接入电网,对多能源长输电系统的仿真研究得到了越来越多的关注。为了进一步提高多能源长输电线系统的仿真效率和实现系统的大规模仿真,提出一种基于长输电线路模型法的仿真接口算法。同时,针对电磁暂态迭代计算中出现的...随着多能源不断接入电网,对多能源长输电系统的仿真研究得到了越来越多的关注。为了进一步提高多能源长输电线系统的仿真效率和实现系统的大规模仿真,提出一种基于长输电线路模型法的仿真接口算法。同时,针对电磁暂态迭代计算中出现的延时问题,提出一种对分割接口进行延时补偿的方法,使得系统在仿真时具有更高的仿真精度。其中,在模型接口算法中采用受控源作为分割接口的控制对象,以实际多能源多电压等级长输电线系统为算例,分别在Matlab/Simulink、实时仿真机(UREP_300)和RT-LAB仿真平台中进行验证。结果表明:设计的长输电线模型(transmission line model,TLM)接口算法与分布式接线用于长输电系统传输时的暂态和稳态结果基本一致,该接口算法适用于离线仿真与实时仿真平台,在提高仿真效率方面具有一定的优势。展开更多
To simulate the process of electrode operation, a dynamic model describing the electrode system of three-phase electric arc furnace was developed. This new model can be divided into three submodels in terms of the pra...To simulate the process of electrode operation, a dynamic model describing the electrode system of three-phase electric arc furnace was developed. This new model can be divided into three submodels in terms of the practical situation. They are the power supply system model the electric arc model and the hydraulic actuator system model. According to the basic circuit theory, the power supply system model where the high voltage transmission circuit and mutual inductances were considered, was set up. The electric arc model, which was novel for the electrode control, served as the electrical load and was connected to the power supply system model. The hydraulic actuator system model consists of the proportional valve part that is modeled to capture the dead-zone nonlinear characteristics and the hydraulic cylinder part where the impact of the load force is taken into account. By comparing simulation data and actual data, the results show that the electrode system model is proved to be accurate.展开更多
The new techniques were presented for preventing undesirable distance relay maloperation during voltage collapse and power swings in transmission grids. Initially, the work focused on the development of a fast detecti...The new techniques were presented for preventing undesirable distance relay maloperation during voltage collapse and power swings in transmission grids. Initially, the work focused on the development of a fast detection of voltage collapse and a three-phase fault at transmission lines by using under impedance fault detector (UIFD) and support vector machine (SVM). Likewise, an intelligent approach was developed to discriminate a fault, stable swing and unstable swing, for correct distance relay operation by using the S-transform and the probabilistic neural network (PNN). To illustrate the effectiveness of the proposed techniques, simulations were carried out on the IEEE 39-bus test system using the PSS/E and MATLAB software.展开更多
The equivalent two-port network model of a middle range wireless power transfer(WPT) system was presented based on strongly coupled multiple resonators. The key parameters of the WPT system include self-inductance, re...The equivalent two-port network model of a middle range wireless power transfer(WPT) system was presented based on strongly coupled multiple resonators. The key parameters of the WPT system include self-inductance, resistance, parasitic capacitance, mutual inductance and S-parameters of coils & resonators were analyzed. The impedance matching method was used to optimize load power and transmission efficiency of the multi-resonator WPT system, and the impedance matching method was realized through adjusting the distances between the coils and resonators. Experiments show that the impedance matching method can effectively improve load power and transmission efficiency for middle range wireless power transfer systems with multiple resonators, at distances up to 3 times the coil radius with efficiency more than 70% and load power also close to 3.5 W.展开更多
文摘随着多能源不断接入电网,对多能源长输电系统的仿真研究得到了越来越多的关注。为了进一步提高多能源长输电线系统的仿真效率和实现系统的大规模仿真,提出一种基于长输电线路模型法的仿真接口算法。同时,针对电磁暂态迭代计算中出现的延时问题,提出一种对分割接口进行延时补偿的方法,使得系统在仿真时具有更高的仿真精度。其中,在模型接口算法中采用受控源作为分割接口的控制对象,以实际多能源多电压等级长输电线系统为算例,分别在Matlab/Simulink、实时仿真机(UREP_300)和RT-LAB仿真平台中进行验证。结果表明:设计的长输电线模型(transmission line model,TLM)接口算法与分布式接线用于长输电系统传输时的暂态和稳态结果基本一致,该接口算法适用于离线仿真与实时仿真平台,在提高仿真效率方面具有一定的优势。
基金Projects(2007AA04Z194, 2007AA041401) supported by the National High-Tech Research and Development Program of China
文摘To simulate the process of electrode operation, a dynamic model describing the electrode system of three-phase electric arc furnace was developed. This new model can be divided into three submodels in terms of the practical situation. They are the power supply system model the electric arc model and the hydraulic actuator system model. According to the basic circuit theory, the power supply system model where the high voltage transmission circuit and mutual inductances were considered, was set up. The electric arc model, which was novel for the electrode control, served as the electrical load and was connected to the power supply system model. The hydraulic actuator system model consists of the proportional valve part that is modeled to capture the dead-zone nonlinear characteristics and the hydraulic cylinder part where the impact of the load force is taken into account. By comparing simulation data and actual data, the results show that the electrode system model is proved to be accurate.
文摘The new techniques were presented for preventing undesirable distance relay maloperation during voltage collapse and power swings in transmission grids. Initially, the work focused on the development of a fast detection of voltage collapse and a three-phase fault at transmission lines by using under impedance fault detector (UIFD) and support vector machine (SVM). Likewise, an intelligent approach was developed to discriminate a fault, stable swing and unstable swing, for correct distance relay operation by using the S-transform and the probabilistic neural network (PNN). To illustrate the effectiveness of the proposed techniques, simulations were carried out on the IEEE 39-bus test system using the PSS/E and MATLAB software.
基金Project(61104088)supported by the National Natural Science Foundation of ChinaProject(12C0741)supported by Scientific Research Fund of Hunan Provincial Education Department,China
文摘The equivalent two-port network model of a middle range wireless power transfer(WPT) system was presented based on strongly coupled multiple resonators. The key parameters of the WPT system include self-inductance, resistance, parasitic capacitance, mutual inductance and S-parameters of coils & resonators were analyzed. The impedance matching method was used to optimize load power and transmission efficiency of the multi-resonator WPT system, and the impedance matching method was realized through adjusting the distances between the coils and resonators. Experiments show that the impedance matching method can effectively improve load power and transmission efficiency for middle range wireless power transfer systems with multiple resonators, at distances up to 3 times the coil radius with efficiency more than 70% and load power also close to 3.5 W.
