Radio Frequency Impedance Matching Based on Control Lyapunov Function

An impedance matching network is mandatory between a source and its load to get the maximum power transfer in any system. These systems can go from antenna adjustment or wireless power transmission to plasma processing technology, widely used in semiconductor wafer processing. Some control strategies have been proposed which aim a robust performance for different impedance matching network configurations; however, they display a slow dynamic or present a power reflection coefficient exhibiting a non-monotonic decreasing behavior, affecting the overall matching control performance. To solve this problem, in this paper, we propose a control technique based on a Control Lyapunov Function (CLF). A dynamic analysis is presented, proving the asymptotic stability of the system. Numerical simulations on a benchmark setup show the improvement of the proposed control scheme and its robustness under different non-ideal conditions.