矽鋼片於高頻脈寬調變激磁狀態下之電磁特性分析

Abstract

本研究的目的在於探討電磁鋼片操作在脈衝寬度調變波形（PWM）下，調整電壓波形參數所對於矽鋼片的電磁特性影響。 研究方法以調整PWM兩參數：振幅調變指數（ma）、頻率調變指數（mf），討論其變化與鐵損值的相關性，並進一步探究振幅調變指數大於1操作下的電磁特性表現。 主要的鐵損分析與討論分成以下部份：（一）各情況下感應電壓波形的諧波分析，討論諧波分佈、大小對鐵損的影響；（二）物理定義上磁滯損、渦流損與異常渦流損的鐵損分離估測，分析不同PWM波形下各鐵損組成的差異；（三）單極切換模式下，以形狀因子係數對鐵損進行估測的效果；（四）雙極切換的小磁滯迴圈現象。 由以上有系統的分析量測實驗，配合即時顯示電磁特性的量測系統，可以有效分析電磁鋼片之特性，有利於電磁鋼片的應用和將來材料的研發工作。

The purpose of this research is to explore the electro-magnetic characteristics of the silicon steel sheets under PWM excitation. The relationship of iron loss and two PWM parameters, including amplitude modulation index (ma) and frequency modulation index (mf), are discussed. Furthermore, the performance of silicon steel sheets which operated under amplitude modulation index higher than 1 is discussed. Analysis and discussions include the following topics: (1) Harmonic analysis of induced voltage waveform and the effect of harmonics magnitude and distribution on the iron loss; (2) To divide iron loss into three parts: hysteresis loss, eddy current loss and excess loss, discussing the difference under various PWM waveform excitation; (3) The estimation of iron loss by form factor coefficient under unipolar switching PWM; (4) The phenomenon and analysis of minor loops under bipolar switching PWM excitation. With the developed systematic measurement and analysis processes, the properties of silicon steel can be obtained by the real-time display software system. This study could be helpful for silicon steel applications and future material development.