Authors: Alexandre Furtado Ferreira
Abstract: In the present work, a technique and model for temperature prediction at the blow end are briefly discussed, along with their limitations and perspectives for application. As a result of this analysis, a mathematical model based in heat and mass balances has been developed with a view to evaluating the possibility of improving this prediction capability. The study here presented focuses the development of a semi-dynamic control model in the LD-KGC converter (Linz-Donawitz-Kawasaki Gas Control Converter). The control model enables one to predict the temperature of the blow end by solving both the energy and mass equations. The inputs to the control model are the load data of the LD-KGC converter at the blow beginning and the collected data by the lance to 89% of oxygen blow. The results obtained in the present work were compared to the data measured in steelmaking. The semi-dynamic control model results agree well with data for LD-KGC converters.
298
Abstract: Paper presents a practical circuit topology and analyzes the converter working process. The converter leading pipe is used MOSFET to achieve a zero voltage turn-on and turn-off, and lagging using is used IGBT to achieve a zero current turn-on and turn-off. After the topology circuit parameters selected by the relevant waveform acquisition, the converter design is verified correct. By running on the power supply operation, converter excellent performance meets the market requirements.
450
Authors: Yue Hua Huang, Zhe Heng Zhou, Hong Tao Fan, Jian Qi
Abstract: In this research, a converter, suitable for the convert station of the HVDC light technology, is proposed and optimized. The converter mainly consists of AC chopper, rectifier transformer, low-pass filters and smoothing reactor. This system can restrain the disturbance of the input power and output the power with high quality. This research is going to analyze the working principle of the converter and then optimize the output wave through filters. Circuit’s simulation is carried out by MATLAB to verify the reliability and feasibility of this converter topology.
1988
Authors: Xian Sui Han, Qi Hui Liu
Abstract: In order to investigate the impacts of large scale PV power plants on the stability of power system, dynamic PV models are of particular interest to the industry for simulating large-scale power systems. The transient model of large scale grid-connected PV generation system was given based on the model of each component of PV generation system. Response of the model was simulated respectively when the illumination changes. The methods proposed could be applied to the power grid with photovoltaic generation integration.
367
Abstract: The key equipment of Light HVDC Technology is the converter and the filter. The main function of the converter is AC / DC conversion, which plays a vital role in converter station. The filter is also an important tool for harmonic suppression. Therefore, in this paper, the HVDC converter and the harmonic suppression are studied. Our paper discussed the advanced converter VSC which is currently being put into operation, its key technology--the MMC topology and the connection mode of VSC. Meanwhile, the production, effect and suppression of the harmonic are analyzed. Compared active power filter to the passive filter, finally, we chose the active filter as the research object. Successful experience of the HVDC Light project which has been put into operation or will be put into use showed that, the technology is in great progress and will be widely used.
391
Authors: Wei Lin Zhang, Jing Xiong, Yu Jiong Gu, Ping Zhu
Abstract: Considering decentralization of the micro-source units and loads in the micro-grid and concentrating on generation types and models of the storage devices, droop control strategy is used in controller design for the distributed generation units. The generation units adopting droop control method based on the droop characteristics can facilitate load power sharing when the powers of loads vary, and can also maintain the system frequency when a unit fault occurs and the micro-grid islands. Then, the operation variations of the micro-grid are analyzed when it runs with load changes in islanding mode and runs with the load power of micro-source varied suddenly. The corresponding rules of the active power, voltage and current for each micro-source and the frequency for the micro-grid are obtained. The simulation data results show the correctness and validity of the droop control strategy.
1151
Authors: Zi Xu Lin, Hong Hua Xu
Abstract: With respect to the permanent magnet synchronous generator, electrical excitation synchronous generator (EESG) can control excitation and its price does not fluctuate with the rare earth materials market, so it has been applied widely. This paper introduces the converter which controls power on excitation instead of the traditional vector control technology. This system has a simple hardware structure, high system efficiency. The simulation results demonstrate the correctness of the proposed converter control strategy.
2563
Abstract: It is very common that the power consumption is too high and the efficiency ratio is too low in the field of the current full-bridge ZVZCS Converter, thus a practical circuit topology is designed and its working process is analyzed to solve the problem. The converter lead pipe can achieve a zero voltage turn-on and turn-off by using MOSFET, and a zero current turn-on and turn-off lagging by using IGBT. By analyzing the relevant waveform of the converter, the correctness of the converter designed is verified.
2863
Authors: Yi Zhen Liu, Xian Yu Deng, Jing Yu
Abstract: The technological process of water treatment automatic control of the steelmaking converter, hardware and software design of the control system are introduced in this paper. The design and realization of water supply automatic control system are based on the S7-400 Programmable Logic Controller.
2356
Authors: Xiao Yan Sun, Yong Qiang Zhu
Abstract: New energy power generation system needs interface converter to connect to the grid. Because the type of new energy is different, its interface converter is also different. In order to adapt to the diversification of the modeling and control strategy of the converter, a generalized interface model is established in this paper. The model is based on the electromechanical transient simulation, which ignores the physics switching device and simplifies the control module. Finally, adaptive verifications are made in PSCAD/EMTDC and Matlab/Simulink for photovoltaic power generation system and wind power generation system. The results of simulation prove the validity of the generalized model.
326