Design Of Electro Slag Shrink Control System And Research On Electrode Synchronous Melt

Traditional casting technology adopts bottom pouring, which means liquid steel gradually fills in ingot molds through the opening of the mold bottom. Due to the cooling features of ingot itself, the method causes cavity shrinkage. The usual solution to this problem is to change the pouring channel. However, the huge volume of heavy mold makes the transformation of pouring channel cost high and take slow effects. While a new attempt to employ the feeding technology of post stage of remitting to feed the top of ingots is able to solve the cavity shrinkage problem with lower cost and higher efficiency so that the new method is suitable for mass production and has great research potential.Based on the design of heavy molded ESHT ingot feeding project of a special steel factory, the technology features and equipment situation of single-phase bipolar tandem feeding method are firstly introduced and special stress is laid on analyzing power supply circuits. According to the requirements of single-phase bipolar tandem feeding process and equipment, computer control system hardware and software are designed and site commissioning is carried out. The lower machine uses Siemens PLCS7-300as its controller and host computer utilizes industrial control computer with WinCC as its monitoring software, thus achieving the design of interface. The system has passed the project examination and reaches all the control indicators.In order to guarantee the flexibility of the equipment, the power transformers for feeding process do not have neutral points. The control method of traditional processes will cause the melting rate of two electrodes unsynchronized, so feeding process cannot last long with lame phenomenon happening easily. This thesis models the circuits of feeding process ideally and proposes new control methods. In addition, this thesis makes promotions on the system by combining fuzzy control and traditional PID control methods. Simulations are conducted using Matlab/Simulink and preferred control effect of synchronous electrodes melting is achieved, which is a favorable trail for future design of feeding control.