設計與分析含短路圈之音圈馬達

Abstract

近年來，由於音圈馬達重量輕、價格低廉而且重現度好，正廣泛地應用在工業上，譬如數位相機和手機相機，因此值得研究音圈馬達的設計與控制。在本文中，以音圈馬達作為致動器，此音圈馬達的永久磁鐵為不動件，纏繞線圈的部分為動件。本研究旨在使音圈馬達線圈的移動時間縮短，移動速度加快。為此，設計了含短路圈之音圈馬達，短路圈位於線圈外側，目的是要大量降低線圈的電感效應，使線圈的電阻-電感電路作用近乎於電阻電路，使電流響應更加快速，並使移動線圈能有更大的加速力量。本文針對含短路圈之音圈馬達做理論推導，並對其系統性能與響應進行電腦模擬。在磁場分析方面，以有限元素方法分析此音圈馬達之磁場。在定位控制方面，本研究以狀態回授控制、模糊控制與順滑模態控制分別對此機構進行補償，進行Matlab軟體的控制模擬與分析，並使安定時間縮短。此研究並製作含短路圈之音圈馬達進行定位控制實驗，並利用雷射位移計測量其位移結果。結果顯示含短路圈之馬達耗費較少的電壓輸入，而且能獲得較大行程。

Recently, the voice coil motor is widely used in the industry owing to it has advantages of light weight, lowest price and good repeatability as digital camera and mobile phone camera. The voice coil motor's design and control are worth to study. In this research, we use the voice coil motor as an actuator. The fixed part of the voice coil motor is a permanent magnet and the moving part is the coil. This study aims to fast move the coil so that the move time can be shortened. To that end, this research places a copper tube (shorted turn) in the outer moving coil. The objective is that an effective inductance seen by the coil is drastically reduced, thus making the coil act more like a resistive element instead of a resistance-inductance circuit. Accordingly, the coil current rises quickly, providing a greater accelerating force right from the start. This theoretical derivation and study computer simulation to investigate controller performance and response. In the magnetic field analysis, this study uses finite element method to analyze the voice coil motor. In addition, concerning positioning control, this research uses state feedback control to compare with fuzzy control and sliding mode control to compensate the mechanism, respectively. We carried out the Matlab simulation and analysis and shorten the settling time. This research designs and fabricates the voice coil motor with shorted turn for positioning control experiment and uses laser displacement sensor to measure the displacement. According to experimental results, the motor with shorted turn in positioning requires less voltage input and generates longer stroke.