Heavy duty inverter welders with high overvoltage immunity

The main objectives of using inverter welders instead of line frequency welders are portability, increased performance, the need to weld special materials such as aluminium or stainless steel, i.e. versatility, and also cost at higher power levels. This paper gives a brief introduction of inverter welders on the market worldwide, and also highlights the special requirements for inverter welders used in African conditions. The zero voltage switching partial series resonant converter, a new robust DC-DC converter having inherent higher overvoltage immunity is presented. It features the use of IGBTs at high switching frequencies, and provides outstanding welding characteristics for a number of different welding processes.