To deal with the stabilizing and robustness problem of the unstable process with timedelay, a novel structure with PIDtype controllers based on BP neural network (BPNN) was proposed. The controller in the inner loop was used to stabilize the unstable process while the outer loop controller which was designed with the BP neural network and PID stabilizing theory purposed by Guillermo was used to improve the performance of the overall system. Simulation result shows that the proposed BPNNPID has good performance in both setpoint tracking and disturbance rejection.

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