Constrained Thermal Plant Control Based on the Second Order Models

This paper deals with the control design for a thermal plant with constrained input signal based on the second order time delayed models. The design follows the requirement of the fastest possible transient processes without overshoot. It is limited to the case when the control signal can potentially attack both the upper and lower saturation limit. For the basic PD controller tuning it is usually enough to use approximation of the original plant by the I2Td model (double integrator + deadtime). The piecewise constant (or slowly varying) disturbances are compensated by a windupless integral action added to the controller output. Here, the loop properties can be improved by using also more sophisticated 2^nd order plant approximation.