Performance monitoring of model predictive control(MPC)technology has received much attention in both academic and industrial circles.For model-based control technique

model accuracy is a key factor to ensure its performance.So model-plant mismatch(MPM)is important in the procedure of control performance monitoring.In recent years

the multi-step prediction error approach for MPC performance potential has been developed without requiring the knowledge of plant model and interactor matrix.However

since the MPC controller has strong robustness to MPM and other uncertainties

the multi-step prediction error approach is not sensitive to performance potential change in MPC controller which is caused by MPM.Considering that model prediction residuals of MPC controller could effectively reflect the information of MPM

an improved approach based on model prediction residuals was developed to resolve this problem.Meanwhile

a performance benchmark and real-time performance monitoring strategy based on the improved approach was defined to monitor MPC control performance.Theoretical analysis and experimental results showed that the improved approach not only possessed the advantages of the original approach

but also could better detect the change in MPC controller performance potential by MPM.Simulation example in the continuous stirred tank heater(CSTH)system illustrated the feasibility and effectiveness of this approach.