We study the effect of potential and thermal gradient induced non-equilibrium magnetization in quasi1-d itinerant magnets.A semi-phenomenological theory is employed in conjunction with the drift-diffusion model forthi...We study the effect of potential and thermal gradient induced non-equilibrium magnetization in quasi1-d itinerant magnets.A semi-phenomenological theory is employed in conjunction with the drift-diffusion model forthis study.Using the methods of non-equilibrium thermodynamics,we derive the transport currents correspondingto charge,heat,and magnetization flows in the presence of non-equilibrium magnetization textures.It is shown howtime-dependent magnetic textures give rise to charge and thermal currents even in the absence of external potential andthermal gradients through spin pumping.The presence of dynamical textures also affect the thermodynamic parametersof the system.As an application,we consider the case of a helimagnet.展开更多
To select the type and value of the impedance of fault current limiters（FCLs） for power network designers, we introduce a new method to calculate the optimum value of FCL impedance depending on its position in the n...To select the type and value of the impedance of fault current limiters（FCLs） for power network designers, we introduce a new method to calculate the optimum value of FCL impedance depending on its position in the network. Due to the complexity of its impedance, the costs of both real and imaginary parts of FCL impedance are considered. The optimization of FCL impedance is based on a goal function that maximizes the reduction of the fault current while minimizing the costs. While the position of FCL in the network has an effect on the calculation of the optimum impedance value, the method for selecting FCL location is not the focus of this study. The proposed method for optimizing FCL impedance can be used for every network that has symmetrical and/or asymmetrical faults. We use a 14-bus IEEE network as an example to explain the process. The optimum FCL impedance used in this network is calculated by considering the vast range of costs for both real and imaginary parts of FCL impedance.展开更多
文摘We study the effect of potential and thermal gradient induced non-equilibrium magnetization in quasi1-d itinerant magnets.A semi-phenomenological theory is employed in conjunction with the drift-diffusion model forthis study.Using the methods of non-equilibrium thermodynamics,we derive the transport currents correspondingto charge,heat,and magnetization flows in the presence of non-equilibrium magnetization textures.It is shown howtime-dependent magnetic textures give rise to charge and thermal currents even in the absence of external potential andthermal gradients through spin pumping.The presence of dynamical textures also affect the thermodynamic parametersof the system.As an application,we consider the case of a helimagnet.
文摘To select the type and value of the impedance of fault current limiters（FCLs） for power network designers, we introduce a new method to calculate the optimum value of FCL impedance depending on its position in the network. Due to the complexity of its impedance, the costs of both real and imaginary parts of FCL impedance are considered. The optimization of FCL impedance is based on a goal function that maximizes the reduction of the fault current while minimizing the costs. While the position of FCL in the network has an effect on the calculation of the optimum impedance value, the method for selecting FCL location is not the focus of this study. The proposed method for optimizing FCL impedance can be used for every network that has symmetrical and/or asymmetrical faults. We use a 14-bus IEEE network as an example to explain the process. The optimum FCL impedance used in this network is calculated by considering the vast range of costs for both real and imaginary parts of FCL impedance.
