Power electronics topologies for plasma generators

The nature of the industrial plasma load requires power electronics topologies with high switching frequencies and tailored output impedance. Depending on the method of coupling to the plasma, the power circuit topology should be selected to provide these characteristics as an inherent property of the circuit. Two design examples of practical interest are given, one for a magnetically coupled toroidal plasma generator and one for a RF generator modulator. This design approach allows the choice of circuit topology to provide load stabilization at the switching frequency, without need for broad band feedback loops and their noise and stabilization problems. This paper describes the specific design of each converter, and presents experimental results supporting the selection of these topologies. These experimental results are measured on full scale units designed for industrial use as products. Results include circuit diagrams, simulations, experimental voltage waveforms, and performance results on plasma loads.