Practical Bumpless Transfer Design for Switched Linear Systems: Application to Aeroengines

Since the output signal of the controller is prone to jump suddenly when a switching occurs, the practical system usually suffers from undesired bumps. To address this "bump" phenomenon, a parameters-free bumpless transfer structure based on multiple differentiators and a cointegrator is proposed in this article. The proposed structure is applicable for switching between manual and automatic modes, as well as switching during steady state and transient state. Unlike the previous compensator-based BT methods, our structure exploits the continuous property of the integrator, which prompts optimal performance and preserves original performance. Furthermore, sufficient conditions based on the dynamic dwell time are given to guarantee the stability of switched linear systems. At last, the designed BT approach is applied to a bivariate turbofan engine and a micro-turbojet engine, wherein the hardware-in-the-loop tests and real bench tests are performed, respectively, so as to demonstrate the significant improvement and potential for practical engineering.