Application of fuzzy adaptive control to a MIMO nonlinear time-delay pump-valve system

•A new application of fuzzy adaptive method to fluid machinery.•Combined fuzzy adaptive control with extended Smith predictor.•The controller only uses inaccurate system model, is insensitive to model accuracy.•Results of the experiment show that the controller is well performed.

In this paper, a control strategy to balance the reliability against efficiency is introduced to overcome the common off-design operation problem in pump-valve systems. The pump-valve system is a nonlinear multi-input-multi-output (MIMO) system with time delays which cannot be accurately measured but can be approximately modeled using Bernoulli Principle. A fuzzy adaptive controller is applied to approximate system parameters and achieve the control of delay-free model since the system model is inaccurate and the direct feedback linearization method cannot be applied. An extended Smith predictor is introduced to compensate time delays of the system using the inaccurate system model. The experiment is carried out to verify the effectiveness of the control strategy whose results show that the control performance is well achieved.