Multi-objective Robust Optimal Control Of The Simulation Study

With the development of science and technology, the control systems become more and more complicated, and at the same time the requirements of control objective increases. To improve system stabilization and performance, multi-objective robust control is presented. So far, robust control has developed almost 80 years and yielded many methods such as H∞,μ-analysis and synthesis etc. They have been applied in many control projects. During the recent 20 years, multi-objective optimization control has developed greatly. For instance, mix H₂/H_∞ control has been applied in the industry, traffic, space flight and so on.At the same time, control system computer aided design (CSCAD) has made great progress continuously. For multi-variable system, researchers have presented many CSCAD software packages or simulation platforms that have been integrated with various different control policies. Applying multi-channel design idea to continuous-time multivariable linear time invariant (LTI) systems, the dissertation makes a deep study of multi-objective robust optimization control theories. And Following these theories, a simulation platform named Motools is presented. The main contributions of the dissertation are as follows:1. First of all, it gives an overview of the development of robust control, multi-objective control and CSCAD. Many typical results about these theories are also introduced and their advantage and disadvantage are discussed. Furthermore, The domestic and overseas development situation of CSCAD is compared.2. On the base of these theories and methods introduced in the dissertation, some study on simulation software has been carried out. The achievements are showed as follows:1) Uses state equations to denote multivariable system, describes the structure of generalized plant, discusses the methods of balance realization and model reduction. Based on the above methods, we havedeveloped two modules: the modeling module and model reduction module.2) The temporal and frequency analysis methods about multivariable system are discussed and realized in Motools software package.3) After introduction of the concep of robust analysis and synthesis, several robust control methods based on output-feedback are discussed. All of these methods are integrated into the package Motools, so that the selections of different methods to design for the same model and comparant of their results are more conveniently.3. Following the multi-channel design idea, we present the output-feedback multi-objective control methods: H∞/H2/GH2/GL2. Their analysis and synthesis in LMIs are discussed. Applying these methods to Motools, we have developed the multi-objective optimization control module, which makes it more efficient in choosing objectives and channels, so we can design the controller again and again until the best result is achieved.4. At the end, we apply the software package Motools to analyze the typical examples of control system. The results indicate that the Motools is useful in education, research and design of control system. Finally, we summarize the limitation of Motools and give some advice to improve it.