The Test Research On The Stability Of New High-speed Turbine Generator Rotor System

As the supplement of the centralized power supply system, distributed energy supply system has incomparable advantages. So the world’s major developed countries pay great attention to it. The distributed energy supply system is also in the rapid development. As the power and energy source, the safe and stable operation of the micro turbine plays a vital role to the distributed energy supply system. Modern micro-turbines always occupy the coaxial high-speed permanent magnet generator, gas-lubricated bearing and other advanced technology. Therefore, the vibration characteristics of the high-speed permanent magnet generator are also received great attention.This article is based on the national science and technology support project" The research and demonstration of distributed energy system". In the article, a finite element analysis of a new type high-speed permanent magnet generator was done. The vibration characteristic experiments of rotor system with different structures, different working conditions were done. The following work was finished:The finite element model of the bearing-rotor system was founded. Based on the model, the inherent characteristic of the system was calculated. The calculations under different gas pressures when the rotor was consisted of single thrust disk and four disks were conducted with the ANSYS software. The Campbell drafts with different supply pressures were obtained which is helpful to the rising speed experiments.The high-speed permanent magnet generator test bench was established. It contained bearing-rotor system, gas supply piping and control system, vibration monitoring and collection system and load system, which was helpful to the conduction of the experiments. The bearing-rotor system was consisted of compressor and turbine, with four disks in rotor. The rotor was supported by the gas-lubricated bearing, which is the same construction with the high-permanent generator.Based on the test bench above, the inherent characteristics of different supply pressures were tested. A comparison between the test results and the calculation results was made. They had a high consistency and the error range was within10%. It indicates the correctness of the finite element analysis.The speed-rising experiments were done with the rotor consisted of four magnet disks and a thrust plate. Through the experiments, the complex spectrum was observed, and the axial rubbing characteristics and parts fall off were observed. In order to increase the stability of the rotor system, the one thrust plate was changed into two thrust plates. The complex spectrum, parts fallen caused by the axial friction were also observed. The axial structure and the magnetic disk analysis were done. The reasons of axial rubbings were concluded, which were helpful to the design of high-speed permanent generator.