Study Of Excitation System For AC Excited Generator

The excitation current of AC Excited Generator (ACEG) is consist of low frequency AC, with the operation and control of frequency and magnitude and phase, ACEG can work on subsynchronous and synchronous and supersynchronous modes of operation, it is mean that ACEG works on variable speed constant frequency(VSCF)modes of operation, and active power & reactive power can be controlled. it cannot lose step even if it operated in deep lead phase, so it may improve the stability of electric power system. Especially, it has been applied to wind power generation system, ACEG has been operated successfully in some countries, so it is deserved that we study on the excitation control strategy for power system development.With the excitation control of the ACEG as the research subject, this dissertation made complete study by simulation and experiment. First, this dissertation analyzes ACEG operation theory, including mathematic modle of ACEG, coordinate transformation, ACEG operation characteristics, ACEG power relationship, which establishes the theoretical foundation for succeeding study. The second, based on mathematic modle of ACEG, we accept vector oriented and vector decoupled analysis. In order to realize decoupled control of ACEG actice & reactive power, a general control strategy based on stator flux oriented vector control was proposed as well. The third, the characteristics of dual PWM converter and the gride-side PWM rectifier are analyzed. The four, A single-machine infinite-bus system model of ACEG was established in this dissertation, with this modle of ACEG, simulation and compare has been worked based on stator flux oriented vector control strategy and direct power control strategy, conclusively ,stator flux oriented vector control strategy was choosed as excitation control strategy of ACEG. At last, an integrated experimental equipment of ACEG was founded, some experiment was done with DSP as processor.