Non-Linear Control Techniques Applied to High Frequency Inverters for Induction Plasma Generator

An induction plasma generator is very attractive for several industrial applications especially in material processing, so a high-frequency power supply class-E inverter is required to generate the magnetic field at frequency ranging from hundreds of kilohertz to tens of megahertz offer high efficiencies at high power densities. A resonant inverter based on zero voltage switching and an adaptive control via a backstepping based on Lyapunov theory and tuning functions control is used as a power supply for inductively Plasma generator. A second technique is applied as a linear quadratic regulator is used as a power supply for plasma generator. This type of control does not only keep the output current and the voltage in phase but also makes the system operating in zero-voltage-switching mode for constant and variable load. On the strategy design of the gains which are determined by minimizing a cost function which reduces the tracking error and the control signal. A recursive least squares (RLS) estimator identifies the plant parameters at different load conditions. The evaluation of the state variables is obtained by estimation using Kalman Filter. Simulation results verified that the proposed strategy has good performance to variable loads providing fast transient response.