功率放大器(简称功放)是磁轴承控制系统中的重要组成部分,磁轴承功放只有具备较宽的通频带范围和良好的响应特性,才能满足系统在大范围内变化时,转子平稳起浮,可靠、稳定旋转。一般商品化的功放产品不能满足使用要求,而应专门设计。由于开关功放的高频毛刺很大,一时无法根除,导致主轴的振动幅度居高不下,为了解决这个问题,提出了利用线性功率放大器的噪声小、振动幅度小的优点,构建大功率线性放大器的设想。其主要思想是将线性大功率晶体管进行并联使用,以扩大其输出的能力。经反复实验和改进,确定了一种实用并联型线性大功率晶体管,为功率放大器的研究提供了一种技术参考。
The power amplifier is the important component of magnetic bearing control system,only when the power amplifier of magnetic bearing has wide frequency band and good response characteristic,the rotor can rotate stably and reliably.General commercial power amplifier can not meet the use but be specially designed.Because of big high frequency burr,the vibration amplitude of spindle is high.In order to solve this problem,the construction of large power linear amplifier was proposed in this paper with the advantages of low noise and small vibration amplitude.The linear power transistor was used in parallel to expand its output.After repeated experiments and improvements,a practical parallel linear power transistor was ultimately determined,which provided a technical reference for future research on the power amplifier.