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Qian H.,Beijing Shougang Automation Information Technology Co. | Hu P.,Beijing Shougang Automation Information Technology Co. | Zhang J.,University of Science and Technology Beijing
Advanced Materials Research | Year: 2012

Solidus temperature is one of the important key parameters to describe the non-equilibrium solidification states. However, the study of the non-equilibrium solidus is not enough presently. In present work, the key Influence factors on solidus temperature have been discussed, and it can be calculated by a mathematical model for solute microsegregation during the solidification. The calculated solidus can be agree with the recommended values by some dynamic soft reduction model. It is shown clearly the thermal analysis with non-equilibrium solidus was consistent with the pin shooting experiments. And the effect of the non-equilibrium solidus temperature on solid fraction and the length of soft reduction zone at the solidifying front has been studied sufficiently. Dynamic soft reduction metallurgical effect with the non-equilibrium solidus has been agreed by carbon segregation index and Macroetched experiment. © (2012) Trans Tech Publications. Source


Xiao X.,University of Science and Technology Beijing | Zhang Y.-J.,University of Science and Technology Beijing | Wang J.,University of Science and Technology Beijing | Su H.-Y.,Beijing Shougang Automation Information Technology Co.
Gongcheng Kexue Xuebao/Chinese Journal of Engineering | Year: 2015

One kind of detection and prediction method for abnormal grid voltage has been designed due to the case that modern power electronic equipment is sensitive to non-stationary time-varying voltage signal. This method sends the network voltage abnormal warning signal to control-circuits of modern equipment through detecting the grid voltage in time. To eliminate the conventional noise jamming of the voltage signal, this scheme adopts linear tracking differentiator to filter the signal. On this basis, wavelet transform modulus maxima are proposed in singularity detection, so as to accurately forecast abnormal harm points in power electronic devices caused by the grid voltage. Simulation and experimental results show that the wavelet analysis based on linear tracking differentiator can obtain the best approximation of the ideal signal and provide more useful forecasting signals for power electronics equipment, thus the fault detection speed and efficiency are improved significantly. © All right reserved. Source


Wang G.,University of Science and Technology Beijing | Li Z.,Beijing Shougang Automation Information Technology Co. | Sun T.,University of Science and Technology Beijing | Xie L.,University of Science and Technology Beijing
CSAE 2012 - Proceedings, 2012 IEEE International Conference on Computer Science and Automation Engineering | Year: 2012

Aimed at the common-mode voltage produced by PWM inverter in motor drive system, the reduction method of three-level PWM inverter output common-mode voltage is investigated. This paper gave the basic principle of three-level inverter, and according to the relation between switch state and the corresponding space vector, then came to a conclusion that common-mode voltage can be reduced by using improved reference vector composes with zero voltage vector and medium voltage vector. At the same time, an improvement space vector modulation program is proposed to reduce the common-mode voltage. The program is simulated by PS IM platform, the simulation results conform to the theory analysis. © 2012 IEEE. Source


Cui H.,University of Science and Technology Beijing | Tian E.-H.,University of Science and Technology Beijing | Chen B.,Shougang Corporation | Qing J.,Hebei Shougang Qian An Iron and Steel CO. | Wang W.,Beijing Shougang Automation Information Technology Co.
Beijing Keji Daxue Xuebao/Journal of University of Science and Technology Beijing | Year: 2014

The influence of the holding time of molten steel in the ladle after RH vacuum process on the T[O] content and non-metal inclusion content of interstitial-free (IF) steel in the tundish was studied to optimize the RH process parameters and improve the cleanliness of IF steel after RH treatment. Experimental results show that as the holding time increases, the T[O] and non-metal inclusion contents decrease at first and then increase. The T[O] content is basically steady below 30 × 10-4 % in the holding time range of 30 min to 40 min except for 4.76% of heats. It is suggested that under current process conditions, the steel mill should control the holding time between 30 min and 40 min. Source


Guo L.,Beijing Shougang Automation Information Technology Co. | Gao L.,Beijing Shougang Automation Information Technology Co.
Proceedings of the 10th International Conference on Steel Rolling | Year: 2010

Because the precision of optimization mathematic model used in load distribution is not high enough, it is difficult to obtain the optimum load distribution and sometimes the regular production is affected, ii the optimization result is used in field direcdy. According to this condition, the paper presents that the fuzzy cluster analysis based on fuzzy equivalence relation can be used to self-adapt the optimization results, using the actual load distribution in field. And then, the results of self-adaption will be optimum and available. It is proved that the method is validity. It gives a self-adaption method to improve the precision of load distribution. Source

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