The Research Of Control System Of Magnetic Suspending Bearing Based On DSP

Active Magnetic Bearing (AMB) is a kind of novel high performance bearing which can suspend the rotor by magnetic force. Because of its contact-free manner between the rotor and stator, comparing with other bearings, it has huge advantages: it has longer lifetime, lower power loss, almost no wear and needs no lubrication, so the rotor can rotate at a very high speed.This paper studies on the control system of AMB with the machine tool in the background. On the basic of analyzing the principle of magnetic suspension bearing, the mathematic model of four-freedom-degree rotor system is erected. Also, I introduce the hardware system's design based on TMS320LF2407A, which concludes hardware and software.The design of hardware: The ADC module integrated in DSP Sample quadruplex signals, then DAC7725P is adopted to convert the dates to low voltage signals, at last, power enlarge circuit amplify the low voltage signals and produce the prospective control signals. The system works at double voltage supplies, and the CMOS chips' proceeding speeds are variable, so it's necessary to design the peripheral circuits, which is as follows: power supply convert circuit, time-delay circuit, etc. To prevent the system confusing, the system adopts CPLD to produce logic coding, which improves the systems' security and reduces the cost.The master-slave working style is used and the parameters of the controller can be revised on line. Adopting the Fuzzy PID method and making reference to experts' experiences, the Fuzzy PID controller according with our experiment is designed. It always makes the system work on the optimum conditions, which is verified by emulation and experiment.