Parameterization of all robust tracking internal model controllers and its comparison with conventional IMC

By using the transfer-function-based factorization approach in the frequency domain, the parameterized representation of all feedforward controllers and feedback filters is derived for internal model control (IMC) systems, which can eliminate steady-state tracking error under the model mismatches and for any given reference input and disturbance. The obtained results can be applied to both continuous-time and discrete-time systems and afford a foundation for further performance optimizations in the frequency domain. An example is given to demonstrate the design process of controller parameterization and optimization. A comparison with conventional IMC and simulation results are also given.