PDF《博士学位论文公示材料》

Chapters

6 and

7 describe fault-tolerant compensation schemes for the PID systems that have been put into operation, i.e., the closed-loop control systems;

in the absence of the stochastic measurement and process noise, that is, under the condition that the aforesaid noise is very small and therefore can be neglected, Chapters

3 and 4, respectively, devote themselves to the solutions to the output-feedback fault-tolerant linear quadratic regulator (LQR) and L2 control problems considering both the actuator and plant failures;

by means of a proposed ADP methodology, Chapter

5 further gives an approach to output-feedback fault-tolerant nearly optimal control in the presence of random noise;

Chapter

6 discusses how to compensate for the actuator and plant faults of digital PID systems with unknown dynamics;

Chapter

7 gives a compensation strategy for multiple simultaneous sensor drift faults in such PID systems. Furthermore, all the theoretical results have been tested by experiment or simulation. The main contents of each chapter in the dissertation are summarized below. Chapter

1 covers the background and significance of this study, and introduces current developments of data-driven FTC technology. Chapter

2 includes a nomenclature part and describes the software and hardware environment of two experimental platforms, i.e., a dual-chamber electric heating furnace and a DC servo system. In Chapter 3, the data-driven design of a residual generator (via a full-rank transformation matrix) is given and a fault detection mechanism is constructed. With the help of the above transformation matrix, the ―4― relation between system state vectors and input-output data is built. As a result, an output-feedback ADP algorithm is devised so as to accomplish the LQR optimal control of unknown linear time-invariant (LTI) discrete-time systems with several outputs. Besides, the chapter presents a time-varying value function approximation structure that is based on both the input-output information and the fault detection mechanism. On this basis, an output-feedback fault-tolerant LQR optimal control scheme without employing any model parameters is proposed. From a control engineering perspective, this scheme is more feasible than the state-feedback-based FTC methodology in [1], where the input matrix of the controlled plant needs to be known. Finally, two numerical examples and a simulation example of a DC motor control system are used to demonstrate the effectiveness and advantages of the suggested methods. In Chapter 4, an output-feedback L2 controller for unknown LTI plants is developed in terms of the data-driven form of residual generators;

for implementation of the tracking control of the closed-loop system constructed with the L2 controller, a pre-filte........