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In order to improve the performance of the active vibration isolation system (AVIS) with electromagnetic actuator, several problems of vibration control are studied. Position control is a critical component in suspension systems, and the position sensor noise can extremely affect the stability of the system, so a tracking differentiator (TD) is proposed to obtain effective differential signal from relative position sensor. In vibration control, the feedback of acceleration combined with PD position feedback is presented to suppress transmission of periodic vibrations. Then, taking the acceleration transmission as the evaluation index, the acceleration transmission under the presented control method is derived, and the influence of control parameters on vibration isolation performance is discussed in detail. The vibration isolation performance is improved from 24.47 dB to 2.4 dB at resonance frequency, and −34 dB attenuation is achieved at 100 Hz with respect to vibration isolation mount system tested on the ground. The experimental results demonstrate that the performance of active vibration isolation system are improved by the proposed acceleration feedback control.

In the clean air conditioning system, in order to ensure that the temperature and humidity in the room are within the allowable accuracy range, it is necessary to control the dew point temperature. However, due to the inconsistency of the temperature and humidity control systems, the delay and inertia time constant of each channel are very different, so the dew point temperature is difficult to control. In order to achieve accurate control, multiple valves are opened at the same time in the system, which leads to energy loss, and usually a single circuit works normally. But when multiple chains work at the same time, the system is not easy to be stable. Therefore, in order to ensure the long-term safe operation of multi-parameter control system, making full use of mature technology and single variable control experience is an effective method to manage multi-parameter system.

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