Reactive power compensation for spot welding machine using thyristor switched capacitor

High-power industrial spot-welding machines make use of transformers that have very high reactive power consumption. Simple reactive power compensation schemes cannot be used however, because of the cyclic nature of the spot welding transformer operating. This paper describes the development of a simple reactive power compensator solution for the spot-welding machines. Focus is also put on the transformer saturation and current transients that can emerge from deployment of such reactive power compensation methods.