TWI Industrial Member Report Summary 410/1990
By M Amin
A linear voltage-current synergic control unit has previously been developed at The Welding Institute to regulate automatically the steady DC open arc MIG operation. Originally, the unit was designed to work with a versatile but high cost transistor controlled power source and then adapted to a low cost and more widely used thyristor controlled power source.
At present, a newly developed inverter controlled power source has become popular because it is small, light, efficient and relatively low cost. Therefore, to promote the wider use of synergic control technology, the control unit has been adapted and tested with an inverter controlled power source in this study.
Two techniques have been used to adapt the control unit to the inverter controlled power source. One uses the generalised 'reference voltage-output current' relationship to take account of the characteristics of the inverter controlled power source. An alternative approach uses the 'voltage feedback control' technique to accommodate the power source characteristics.