Abstract: In this paper, a linearized mathematical model of the delayed negative feedback oscillation is derived. In order to improve the sta-bility and disturbance rejection o.f the cabin temperature control system,a new approach to the design of pre-sensing bridge circuit is presented. The pro-sensing brige so designed can realise a lead-correction with time-constant as high as a few thousand seconds. Besides,by employing the existing engine control system installations, without any additional parts a feedforward control method for rejecting disturbance can be achieved.

Key words: oscillation linearization, pre-sensing bridge, feed-forward control