Low-voltage Electromagnetic Riveting Equipment Control System

Electromagnetic riveting is a new kind of riveting process and has been employed in aerospace industry. It is a key technique to be used to solve problems such as riveting of high strength rivets, large diameter rivets ,composite structures etc. Electromagnetic riveting equipment in our country is not good enough to be used. Researches have been done on controlling system of low voltage electromagnetic riveting equipment in this paper, to expect to apply low voltage electromagnetic riveting in the manufacturing process.The discharge circuit of electromagnetic riveting equipment had been set up to find out the factors that have effect on electromagnetic riveting process. The appropriate capacitor and charging voltage parameters of controlling system have also been obtained according to practical application.A new controlling system of low voltage electromagnetic riveting equipment based on Programmable Controller (PLC) is designed. Hardware circuits include bridge charging circuit with thyristors, triggering circuit with TCA785 chip and capacitors discharging circuit. PLC software mainly uses charging current and voltage to implement series-wound PID closed-loop control. The result of PID is regarded as control voltage of triggering circuit to ensure charging quickly and accurately. PLC software executes PID closed-loop control, so the controlling system has good flexibility.The low voltage electromagnetic riveting tank based on electromagnetism compatibility and practical application is worked out.