基于FPGA的磁悬浮轴承电控系统设计

Electric control system design of magnetic bearings based on FPGA

针对模拟或基于DSP的磁悬浮轴承控制器和功率放大器,具有集成度和可靠性低及体积庞大的局限性,设计了一种基于现场可编程门阵列(FPGA)的磁悬浮轴承电控系统.首先应用MAT-LAB对各部分进行了建模,然后针对各部分参数对其性能的影响进行了仿真研究,最后对基于FP-GA的数字功率放大器的纹波与动态特性进行了试验,并将它们应用到磁悬浮球系统中实现了悬浮球的稳定悬浮.结果表明:该数字控制器使磁悬浮球悬浮时的振动量控制在15μm;设计的数字功率放大器在母线电压为150 V,开关频率为25 kHz,负载线圈电感为40 mH,静态电流为2 A时,功率放大器的电流纹波为300 mA,截止频率在350 Hz左右.

To solve the problems of low integration level and reliability of magnetic bearing system controllers and power amplifiers based on analog circuits or DSP,a new type of magnetic electric control system was designed based on the field programmable gate array（FPGA）.The control system was modeled by MATLAB to simulate the influences of parameters on system performance.According to the ripple and dynamic characteristics of FPGA digital power amplifier,the new system was applied for magnetic suspension ball system to realize ball suspending.The results show that the vibration magnitude of the ball can be controlled at 15 μm.Under the operating conditions,bus voltage of 150 V,switching frequency of 25 kHz,load coil inductance of 40 mH and static current of 2 A,FPGA-based system can realize stable suspension with power amplifier current ripple of 300 mA and cut-off frequency of 350 Hz.This new type digital controller can meet the demands of AMB system.