Research On Synchronous Generator Digital Brushless Excitation Based On Rotating Converter

With the rapid developments of large scale integrated circuits, digital control and computer technology, the digital electronic technology has been gradually applied to modern excitation systems, replacing the traditional analog excitation controller and form the digital automatic excitation controller.This paper introduces a novel digital brushless excitation technique of synchronous generator based on rotating converter. This new technique is based on Rotary Inductive Power Transfer technique. The key component of this system is the rotating transformer which connects the static part and the rotating part. The primary part of this transformer is static, while the secondary part is integrated with the rotor which can rotate with the shaft.It can supply a constant and adjustable exciting current to synchronous generator by transferring electric power from a static part of the converter to the rotating part without a real connection.This new excitation technology is more reliable and durable than traditional electrical sliding, and has a more extensive application prospects.The software and hardware platform of digital brushless excitation system was designed successfully based on DSP56F8013,a low-cost DSP production of freescale.There are two research parts in this paper. Firstly, it introduces the design of digital phase-shifted full-bridge rotating converter, including the principle of rotating converter,ZVS mode analysis of rotating converter and the principle and working characteristics of the rotating transformer. Secondly, it does some research of the synchronous generator used for brushless experiments. The simulation model and experiment platform for the whole brushless system are established, The results between simulation and experiments are given, and it illustrates that the rotating converter can meet the requirements of the synchronous generator excitation system. So the technique of rotating converter is not only a break through on brushless excitation of synchronous motor, but a new direction for the research of this field.This subject is supported by NSF(NO.50477013)...