A 500W high efficiency class-E power amplifier for heating a variable plasma load at 10MHz

In this contribution, a high efficiency class-E power amplifier is presented, which is optimized with respect to heat a variable plasma load at 10MHz. First of all, the design of the class-E amplifier is demonstrated. Therefore, after the fundamental design equations, the dimensioning of amplifier's lumped elements is presented. Furthermore, simulations and measurements are performed in order to verify the functionality and efficiency. During this, two high power MOSFETs from Microsemi and IXYS are compared. An efficiency of 90.7% at 507W output power and 50Ω load is achieved. The resistance of the plasma load can change between 200Ω and 300Ω. Therefore, an optimized matching network, which provides an almost constant output power of ±1% in the desired load resistance range, is presented.