Decoupling PI controller design for aeroengine

In discrete-time domain, the optimal PI controller design problem for aeroengine was researched. Firstly, a general coupling PI controller design method was presented. The key ideas were to construct Lyapunov function to guarantee the closed-loop stability, and the performance was optimized under the given evaluation index. The controller design results can be cast as a convex optimization problem involving a set of linear matrix inequalities (LMIs), which can be solved efficiently with commercially available software. Then, considering engineering application status in China, to suit for the large thrust turbo fan aeroengine model characteristics and meet the control requirements, a decoupling PI controller design method was developed based on the general method, by constructing special PI controller and matrix variables. The influence of performance evaluation index matrix selection to controller design results was discussed, and the suggested structure of performance evaluation index matrix was presented. Finally, an example was presented to verify the proposed theoretical results.