The Research On Excitation Control System Of Synchronous Based On Nonlinear Theory

The excitation of synchronous generator plays an important role in power system. A good design excitation can maintain voltage effectively, and improve the stability of system. Compare to other measure focus on improve stability of power system, excitation is more inexpensive and more easily to carry out.Firstly, the paper introduces the developing tendency of excitation of the excitation means and the excitation controller. The mathematics models of single generator-infinity strap transmit electricity system and something about the stability of power system also lucubrated in this paper. Secondly, the paper studies the basic ideas of nonlinear PID controller (NPID), composed of the nonlinear tracking-differentiator (TD) and nonlinear combination, which is advanced by professor Han in Chinese Academy of Sciences. The theory of chaos optimization of parameters, which using the chaos variables' property of stochastic, ergodic and regular, also analyzed in this paper.Based on forenamed knowledge, the paper designs a double-loop NPID excitation controller, which has parallel feedback of voltage and error of rotate-speed. By using chaos optimization algorithm, the paper tunes the parameters of NPID excitation controller. Compared with PID and LOEC methods, it has good robust to disturbances of power system, it can improve not only the voltage characteristic, but also the steady state stability and transient stability of power system. The simulation processes are mostly depending on Matlab, and the simulation results of the control system are satisfactory.Aim to the demand of Hunan Unis Measure & Control Co. Ltd., the paper designs a digital excitation controller, which will mainly apply to miniature hydropower station. The paper deals with the design of the 16-bit single-chip-based excitation controller's hardware and the configuration, flowchart and realization methods of its software from the aspects of min-system of single-chip, I/O channel, human-machine interface, formation and amplify of the trigger pulse etc. As well as, the practical measures of hardware and software to resist the interfering are explained in the paper. The results of testing show that the digital excitation controller have simple and reliable structure, convenient application and maintaining, flexible control, but it need to test its adjust performance more by experiments at present.-n-In the paper, the nonlinear PID controller is applied to excitation control of synchronous, which parameters tuning quote the method of chaos optimization. The way effectively disposes the difficulty of parameters tuning of NPID controller, offer a new idea of excitation control of synchronous. The digital excitation controller has favorable performance and low cost, which designed by the idea. It holds for most of the miniature hydropower station, has good benefit for the economy and society.