Observation of state variables in resonant DC-DC converter using the high gain design approach

We are considering the problem of state observation for in series resonant converters (SRC). This is a crucial issue in SRC output voltage control because the control model is nonlinear and involves nonphysical state variables, namely real and imaginary parts of complex electrical variables. A high gain observer is designed that ensures global exponential convergence of state estimates to their true values. The observer design involves no resolution of complex dynamical or algebraic equation. The global and exponential features of state estimate convergence make the observer utilizable in control.