科创中国

选择IGC(产业梯度系数)作为衡量区域产业梯度水平的指标,通过计算豫沪苏浙产业梯度系数,结合国情、省情,明确在"十二五"期间,河南省宜承接的工业产业.

Further development of the photovoltaic industry is restricted by the productivity of mono-crystalline silicon technology due to its requirements of low cost and high efficient photocells.The heat shield is not only the important part of the thermal field in Czochralski(Cz)mono-crystalline silicon furnace,but also one of the most important factors influencing the silicon crystal growth.Large-diameter Cz-Si crystal growth process is taken as the study object.Based on FEM numerical simulation,different heat shield structures are analyzed to investigate the heater power,the melt-crystal interface shape,the argon flow field,and the oxygen concentration at the melt-crystal interface in the process of large Cz-Si crystal growth.The impact of these factors on the growth efficiency and crystal quality are analyzed.The results show that the oxygen concentration on the melt-crystal interface and the power consumption of the heater stay high due to the lack of a heat shield in the crystal growth system.Argon circumfluence is generated on the external side of the right angle heat shield.By the right-angle heat shield,the speed of gas flow is lowered on the melt free surface,and the temperature gradient of the free surface is increased around the melt-crystal interface.It is not conducive for the stable growth of crystal.The shape of the melt-crystal interface and the argon circulation above the melt free surface are improved by the inclined heat shield.Compared with the others,the system pulling rate is increased and the lowest oxygen concentration is achieved at the melt-crystal interface with the composite heat shield.By the adoption of the optimized composite heat shield in experiment,the real melt-crystal interface shapes and its deformation laws obtained by Quick Pull Separation Method at different pulling rates agree with the simulation results.The results show that the method of simulation is feasible.The proposed research provides the theoretical foundation for the thermal field design of the large diameter Cz-Si monocrystalline growth.

The existing research of the acceleration control mainly focuses on an optimization of the velocity trajectory with respect to a criterion formulation that weights acceleration time and fuel consumption. The minimum-fuel acceleration problem in conventional vehicle has been solved by Pontryagin's maximum principle and dynamic programming algorithm, respectively. The acceleration control with minimum energy consumption for battery electric vehicle(EV) has not been reported. In this paper, the permanent magnet synchronous motor(PMSM) is controlled by the field oriented control(FOC) method and the electric drive system for the EV(including the PMSM, the inverter and the battery) is modeled to favor over a detailed consumption map. The analytical algorithm is proposed to analyze the optimal acceleration control and the optimal torque versus speed curve in the acceleration process is obtained. Considering the acceleration time, a penalty function is introduced to realize a fast vehicle speed tracking. The optimal acceleration control is also addressed with dynamic programming(DP). This method can solve the optimal acceleration problem with precise time constraint, but it consumes a large amount of computation time. The EV used in simulation and experiment is a four-wheel hub motor drive electric vehicle. The simulation and experimental results show that the required battery energy has little difference between the acceleration control solved by analytical algorithm and that solved by DP, and is greatly reduced comparing with the constant pedal opening acceleration. The proposed analytical and DP algorithms can minimize the energy consumption in EV's acceleration process and the analytical algorithm is easy to be implemented in real-time control.

电机温升对电机的性能有重要影响,是电机设计的关键.基于流体动力学原理,对矿用防爆电机的热流耦合场进行数值计算,得到了电机内部流场特性、电机整体温度分布、电机各部件峰值温度及所在位置.通过方案比较,确定定、转子铁心长度;然后进行结构优化,采用电机内置风扇、定转子铁心增设通风孔两种方法增强电机内部冷却效果,并验证数值计算的可行性.所得结论为电机设计提供了一定的理论参考.

针对为胶囊内窥镜供能的无线能量传输技术在应用过程中对人体组织可能造成伤害的问题,进行了无线能量传输系统发射线圈优化设计研究.分析了人体组织安全性与无线能量传输系统发射线圈之间的关系,提出用磁场均匀度、频率稳定度等指标来评价发射线圈性能,并建立了以能量传输效率为目标函数、以人体安全性和能量需求为约束条件的最优化模型.该模型可用来全面评价发射线圈性能,从而为发射线圈的设计提供依据.采用上述方法对4种类型的发射线圈进行了评价,评价结果证明了该方法的可行性.