An investigation of turbogenerator dynamics and control

Mohammed, Zakaria Fadlalmoula (1996) An investigation of turbogenerator dynamics and control. PhD thesis, University of Glasgow.

Abstract

This thesis provides an investigation of the dynamics and control of turbogenerators from a multivariable control viewpoint. The multivariate control framework chosen -Individual Channel Analysis and Design- is particularly appropriate since it encapsulates the dynamical characteristics of the uncontrolled system with a view to exposing the potential and limitations for subsequent closed-loop control. The main contribution of the thesis is a complete new insight into why excitation/governor control with Power System Stabilisers (PSS) has been so successful for the control of turbogenerators connected to an infinite bus provided by the small-signal multivariable analysis framework, Individual Channel Analysis and Design. The multivariable analysis justifies treating the turbogenerator system as a pseudo- Single-Input Single-Output, (SISO) system where the governor loop is first closed and the exciter loop is treated as a SISO system for the prime purpose of rejecting voltage disturbances.

The function of the PSS is identified as that of overcoming an awkward switch-back frequency-domain characteristic of the excitation channel so as to permit high-performance excitation channel bandwidths up to 10 rad/sec that otherwise could not be obtained. Thus, in addition to the control requirements of set point regulation of the terminal voltage and shaft speed, the PSS provides for a second control requirement of strong voltage disturbance rejection over the important frequency range of 0 to 10 rad/sec. The PSS control option is also assessed against other control options. Several other results concerning stability robustness to system uncertainties in different system configurations follow from the analysis in a transparent and immediate way.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Subjects: T Technology > TK Electrical engineering. Electronics Nuclear engineering
• Colleges/Schools: College of Science and Engineering > School of Engineering
• Supervisor's Name: O'Reilly, Prof. John
• Date of Award: 1996
• Depositing User: Elaine Ballantyne
• Unique ID: glathesis:1996-1727
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 15 Apr 2010
• Last Modified: 10 Dec 2012 13:45
• URI: https://theses.gla.ac.uk/id/eprint/1727