Rogowski电流传感器及其在电阻焊数据采集中的应用

Rogowski线圈电流传感器由均匀密绕的挠性空心线圈和积分器构成,由于其原理和结构特点,特别适合于电阻焊次级电流的测量.讨论了Rogowski线圈工作原理、积分器设计及误差、传感器电路模型和灵敏度的频率响应,设计了用于电阻焊测量的电流传感器,据此研制出ADuC812单片机为核心的电阻焊数据采集系统,并进行了低碳钢板搭接点焊试验和电压电流等信号的采集.初步分析认为,焊接电压、电流信号及接头动态电阻、输入功率与熔核形态密切相关,可用于电阻点焊接头质量的在线监控.

Rogowski current transducer applied in data collection of for resistance spot welding

The Rogowski coil current transducer consisting of a flexible 'air cored' toroidal winding and an integrator is applicable specifically to the secondary current detection in resistance welding process, due to the its operation principle and structural feature. The operation principle of the Rogowski coil, design and error of the electronic integrator, circuit model and sensitivity response characteristic of the transducer are discussed. A data gathering system based on AduC812 MCU is developed with the designed current transducer for resistance spot welding, by which the voltage and current signals are acquired in resistance spot welding test for mild steel board. The preliminary analysis shows that the voltage and current signal waveform, dynamic resistance, and input power of the welded joint correlate closely with the morphology of melt nugget, and they can be utilized in on-line quality monitoring of resistance spot welding.