Displacement Threshold Vibration Compensation for Magnetically Suspended Turbomolecular Pump With Gradual Unbalance

As the core equipment of the ultra-high vacuum system, the magnetically suspended turbomolecular pump (MSTMP) is widely used in the semiconductor manufacturing equipment (SME). Nevertheless, the gradual unbalance caused by the corrosion and deposition of tail gas on the turbine rotor during semiconductor industry processes, significantly jeopardizes the long-term reliable operation of MSTMPs. To address this critical challenge, a displacement threshold vibration compensation method was proposed in this article by analyzing the MSTMP rotor system under automatic balance control. First, a normalized displacement threshold correction method is proposed to enhance the compensation accuracy by rectifying the fixed displacement threshold. Second, to mitigate the latency issues of power amplifiers at high rotational speeds, a double closed-loop compensation method was established. Finally, the effectiveness and feasibility of the proposed method in this article are verified by simulation and experiment. The method proposed in this article provides potential support for the promotion of MSTMP in the SME.