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With the renewable energy application fields of film capacitors gradually expanding, mining film capacitors' data is an important issue. When the aging mechanism and environment are unfamiliar, it will be hard to extract the capacitance's variation law and predict its changes. At the same time, the parallel operation of film capacitor components also brings practical needs and data basis for collaborative prediction. In this work, the capacitance of five film capacitors at room temperature and humidity for 70 days was measured and the characteristics of capacitance variation were analyzed. Then, the capacitance law extraction, single prediction, and collaborative prediction methods for film capacitors were proposed based on the smoothing splines theory. Finally, the effectiveness and application potential of the single prediction and collaborative prediction methods were verified by actual data. The performance of the single prediction and collaborative prediction methods is evaluated by error analysis. The single prediction and collaborative prediction methods proposed in this work can also provide a reference for the prediction and evaluation of other parameters like equivalent series resistance of film capacitors, and help to effectively and accurately explore the aging mechanism.

To design a non-overlap vertical electrostatic combdriver for the optical translational micromirror of an optical phase modulator,a mathematic model based on the conformal mapping was built to research the driving performance of the combdriver in detail.According to the theory of complex variable function,an analytical model was established for the electrostatic field of comb actuator by conformal mapping.Then,the electrostatic force in a certain displacement range was deduced by the analytical model for researching the movable comb finger.The results were compared with the corresponding resolution by the Finite Element Method(FEM).Finally,a non-overlap vertical combdriver was successfully fabricated by Micro Electronic Mechanic System(MEMS) process,and an optical Michelson interference system was constructed to measure the static driving charateristics of the comb driver.The result shows that the displacement of proposed non-overlap vertical electrostatic combdriver is 325 nm(phase difference 2π) with a dc driving voltage of 28 V and the offset vertical comb actuator can be actuated to 2.07 μm under a dc driving voltage of 90 V.The measured results accord excellently with the simulated results using the conformal mapping and FEM method,which proves proposed analytical model to be correct.It can provide theoretical and pratical bases for design of non-overlap vertical electrostatic combdrivers.

In order to obtain a micro-mirror array with large torsional angles and large sizes under limited driving voltages,a novel micro-mirror array with a multi-terraced-plate structure was proposed and demonstrated based on the Micro-optoelectro mechanical System(MOEMS).The different characteristics of the electrostatic driver between multi-terraced-plate structure and parallel-plate structure were analyzed.The key fabrication process for the multi-terraced-plate structure was researched and a bulk micro-mechanical technology was used to fabricate a micro-mirror array with the multiterraced-plate structure.The obtained micro-mirror array contaning 52 micromirrors has the size in 600 μm by 200 μm,and a high fill-factor in excess of 97%.The test results show that the micro-mirror array achieves a maximum torsional angle about 1.1° under a driving voltage of 164 V,and the multi-terraced-plate structure greatly reduces the driving voltage as compared with the traditional parallel-plate structure.