Energy management strategy of battery in isolated micro-grid based on state of charge(SOC)
Through the research on modeling and SOC estimation of the battery in the isolated Micro-grid, the behavior characteristics of the battery was analyzed under normal and stable operation, and further more, the condition was determined to guarantee the stability of system based on SOC of the battery. Under the premise of stable operation, a control strategy was put forward based on SOC to adjust the battery charging or discharging. The simulation shows that, compared with the system under traditional control strategy, the security and reliability of the power system is improved evidently. Keywords-Battery SOC Estimation Micro Grid Matlab/Simulink Simulation
Voltage characteristics of Li-ion power battery for EVs
The focus of this research is LiMn_2O_4 Li-ion battery and LiFePO_4 Li-ion battery for electric vehicles in the field of application of power.The voltage characteristics of four kinds of domestic power LIB batteries are tested and researched.The test results show that,there are significant differences on the voltage characteristics between LiMn_2O_4 LIB and LiFePO_4 LIB.Low temperature has the significant influence on LiFePO_4 LIB's voltage characteristics;PNGV model is applicable to the simulation of voltage characteristics when LiFePO_4 LIB is under the dynamic pulse current driving schedule.
Numerical tools applied to power reactor noise analysis
In order to be able to calculate the space- and frequency-dependent neutron noise in real inhomogeneous systems in two-group theory, a code was developed for the calculation of the Green's function (dynamic transfer function) of such systems. This paper reports on the development as well as the test and application of the numerical tools employed. The code that was developed yields the space-dependence of the fluctuations of the neutron flux induced by fluctuating properties of the medium in the two-group diffusion approximation and in a two-dimensional representation of heterogeneous systems, for both critical systems and non-critical systems with an external source. Some applications of these tools to power reactor noise analysis are then described, including the unfolding of the parameters of the noise source from the induced neutron noise, measured at a few discrete locations throughout the core. Other concrete applications concern the study of the space-dependence of the Decay Ratio in Boiling Water Reactors, the noise-based estimation of the Moderator Temperature Coefficient of reactivity in Pressurized Water Reactors, the modeling of the beam- and shell-mode core-barrel vibrations in Pressurized Water Reactors, and the investigation of the validity of the point-kinetic approximation in subcritical systems driven by an external source. In most of these applications, calculations performed using the code are compared with at-power plant measurements. Power reactor noise analysis applications of the above type, i.e. core monitoring without disturbing plant operation, is of particular interest in the framework of the extensive program of power uprates worldwide.