Classical Linear Control Systems—PID Control Systems
The main topic of this chapter is concentrated on the PID control system design and analysis. Three popular methods, root locus, Bode plot, and state space, are introduced and discussed in details with quite a few example projects. Starting from Sect. 5.2, the root locus strategy is discussed with some special properties used in this method. The effects of poles and zeros on time-domain specifications are discussed. Then the sketching of root locus by manually is introduced. Two typical compensators, phase lead (PD) and phase lag (PI), are introduced and analyzed with some examples. Some popular and powerful computer-aided design and analysis tools with root locus method, such as MATLAB root locus design functions and SISOTool, are discussed in details. The PID controller design with Bode plot frequency response method is introduced and analyzed in Sect. 5.3. Three popular computer-aided design tools, SISOTool, PIDTuner, and MATLAB Simulink, are discussed with some actual example systems. The Nyquist stability criterion is also introduced and discussed with some useful MATLAB functions. The PID controller design with state-space method is introduced in Sect. 5.4. Some important and related properties and features are discussed in detail in this part. An actual PID closed-loop controller for a real DC motor system is discussed as a case study in Sect. 5.5. A real DC motor, Mitsumi 448 PPR Motor, is utilized as a target plant for this closed-loop control system to help users to build a real control system with TM4C123GH6PM MCU system. The detailed control programming codes are provided with detailed discussions.