Henan Zhongfu The 300ka Grade Aluminum Electrolytic Steady Flow Control System And Application

Aluminum electrolysis is a high-energy consumption industry and the energy saving of production process is a problem needed to be solved urgently. In the production process, to keep series current stable can improve the current efficiency of electrolysis process and reduce the electric power consumption and anode effect times. The improvement of the stability and current stabilizing precision of the rectifier power system can reduce the power consumption per ton aluminum and increase the yield. It is significant to improve the economic benefit and market competitiveness for the enterprise.Under the background of technique reformation of the rectifier power system of 110KV rectifying station in Zhongfu, Henan province, the basic situation of rectifier power system for aluminum electrolysis and the present situation of automatic stabilized current control system are analyzed. The working principle and implementation method of digital stabilized current control system are illustrated and the general design scheme of the system and the hardware design scheme are proposed. It adopts the control and communication technology based on the programmable logic controller and uses the isolated gate bipolar transistor (IGBT) as the power unit, using the technology of pulse width modulation to realize the current regulation. The double-loop control strategy of digital stabilized current system based on PI regulation is established, imbedded with big closed-loop and small closed-loop. Furthermore, using the WinCC and STEP 7 as development tools, the software of automatic stabilized current control system is developed. Finally, after the system installation, the overall field debugging of the stabilized current control system is completed. The system has been put into operation in industrial production process successfully.The running results showed that the current stabilizing precision and stability of the system are improved. Moreover, the safety and stability of the rectifier transformer and rectifier cabinet are enhanced greatly. It is significant to lower single ton aluminum consuming of the electricity and reduce pollution of the environment with the application of the system for the enterprise.