The Development of the Pneumatic Transmission Lag Compensator and its Effects

In order to minimize the transmission lags associated with the pneumatic instrumentation, the Transmission Lag Compensator (TLC) was developed. The construction and features of the TLC which is based on the phase lead compensation are described. The effects of applying the TLCs are investigated by experiments and simulations. Experiments with practical plants using the TLCs show the improvement of the control performance over the system without the TLC. The effects of applying the TLCs are also obtained quantitatively from the control performance simulations.