Abstract：Biased current control consumes large amounts of power which increases system temperatures and causes temperature drift in sensors which then affects the levitation accuracy. The rotor suspension is also affected by unbalanced forces, sensor runout and other effects which lead to vibrations. This paper presents a zero-bias current strategy based on a multiple frequency notch filter. The zero-bias current control algorithm reduces the power consumption, handles the nonlinearities in the zero-bias current strategy, and translates the nonlinear relationship between the current and the displacement into a linear relationship between the magnetic force and the displacement so that a linear control strategy can be used. The multiple frequency notch filter then suppresses the vibrations. Three controllers are analyzed in tests with no unbalanced control, only single frequency notch filter control and multiple frequency notch filter control to verify the system effectiveness. The method not only suppresses the vibrations, but also significantly reduces the power consumption.
荣海, 周凯, 毛飞龙. 基于零偏置电流的磁悬浮电主轴动不平衡力抑制[J]. 清华大学学报（自然科学版）, 2019, 59(8): 683-688.
RONG Hai, ZHOU Kai, MAO Feilong. Suppression of imbalance vibrations in magnetically suspended spindles based on zero-bias current control. Journal of Tsinghua University(Science and Technology), 2019, 59(8): 683-688.
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