Research on Vacuum Consumable Arc Remelting Furnace Control System with Drop Short Pulses Testing

Abstract

Stable and Reliable automatic control system of Vacuum Consumable Arc Remelting (VAR) furnace is the key to smelt successfully special alloy metal and high temperature alloy metal, which is related to special properties of remelting ingot directly. This paper makes a deep study for drop short pulse testing and controlling system, and digital signal processing is used to obtain drop short pulse value with different frequency ranges. Firstly, basic theory analysis of drop short pulse measuring and controlling is researched. Secondly, high-speed digital signal processing technology is adopted to sample furnace voltage signal real-timely, band pass filter group is designed directly to process and calculate the amount of drop short pulses in different frequency ranges, Finally, the relationship between drop short pulse frequency and special alloy materials is analyzed, fuzzy PID control method is used to adjust electrode gap and control arc length. Field experiment results show the effectiveness of the whole drop short pulse testing and controlling system.