Digital switch power amplifier for magnetic suspension flywheel magnetic bearing system

Abstract

The invention is a digital switching power amplifier for magnetic bearing system of magnetic suspension flywheel, a device for actively controlling the current in the magnetic bearing coil, mainly comprising FPGA, isolated driving circuits, full-bridge main circuit, current detection circuit, conditioning circuit, A / D chip and overcurrent detection circuit. And the digital switch power amplifier makes PWM modulation by the error signal formed by the FPGA according to the given digital control quantity and sampling result of current feedback signal, directly control ON and OFF of power switches in the full bridge main circuit by the ready- modulated PWM signals through the isolated driving circuits, so as to achieve the purpose of controlling the current in the magnetic bearing coil. And the invention has advantages of simple structure and high reliability.

Description

technical field [0001] The invention relates to a digital switch power amplifier for a magnetic bearing system of a magnetic suspension flywheel, which is used for controlling the output current of the magnetic bearing coil of the magnetic suspension flywheel. Background technique [0002] The flywheel is the basic attitude control actuator on small and medium-sized satellites with stable three-axis attitude. Compared with the traditional mechanical bearing flywheel, the magnetic levitation flywheel has the advantages of no speed, zero friction and active vibration control. Therefore, it has the advantages of high-precision satellites. Broad application prospects. In addition, the magnetic bearing has no friction, which avoids the wear of the mechanical bearing itself due to friction. Its reliability depends on the reliability of the electronic components of the control system, so it has a longer service life than the mechanical bearing flywheel. [0003] As the actuator of...

AI Technical Summary

Problems solved by technology

Switching power amplifiers based on analog devices have low integration, high power consumption, and inflexible pulse width modulation methods, while switching power amplifiers based on single-chip DSP have a limited number of PWM signal outputs. Multi-chips are required to complete multi-channel control. DSP, resulting in reduced reliability, waste of resources, and fixed PWM modulation, so the magnetic bearing switching power amplifier based on analog devices and DSP is not suitable for space applications

In addition, in current switching power amplifiers, the isolation of PWM signals and the isolation of current feedback signals are generally implemented by switching optocouplers and linear optocouplers. In space environments, optocouplers have poor reliability and should be avoided when selecting satellite devices. Not suitable for use in space environment applications

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