Current Measurement of Resistance Spot Welding Using DSP

This study aims to calculate the resistance spot welding current digitally at a fast speed. The conventional open-loop spot welding machine cannot measure the current, thus the welding quality varies. The welding time of spot welder is very short, but the welding current is strong and it is hard to be measured, thereby resulting in the uncontrollability of welding quality. This study uses a high speed, low price and high-performance 32-bit ADSP21065 SHARC digital signal processor (DSP) as the core to measure the welding current in real time. The experimental results are compared with the commercial welding current meter to prove that the proposed method can quickly and accurately calculate the welding current.