電磁鋼片於弦波、脈寬調變之鐵損量測及新型環形測試器之研發

Abstract

本文係建立靜態鐵損測試系統以量測矽鋼片之電磁特性，自製包括一般環形測試器、標準25cm-Epstein 測試器及創新結構環形測試器；藉由控制不同的電壓輸入訊號，如弦波訊號及脈寬調變訊號，分析矽鋼片鐵損特性與輸入訊號間的關係，以作為設計變壓器或馬達時參考之用。研究內容分為四部分：（一）建立三種繞線方法之一般環形測試器，另依據ASTM 標準建立0.5kg、2kg 之25cm- Epstein測試器，並搭配資料擷取卡、線性功率放大器及電力計等相關設備完成靜態鐵損測試系統。（二）在弦波量測方面，量測範圍為50Hz~5kHz，將其實驗結果與中鋼之資料相互比對，以驗證自製測試系統之準確性，並比較環形測試器於不同繞線方式的差異性。此外，透過感應電壓之波形控制，顯著提升弦波鐵損之量測範圍。（三）在脈寬調變量測方面，設計一多功能全橋式PWM 換流器電路以完成PWM 鐵損量測系統，分析單極切換、雙極切換及不同調變指標等條件對鐵損所造成的影響。（四）研發一創新結構環形測試器，經實驗驗證不但具準確性，並可快速替換試片，方便量測其電磁特性，免除一般環形測試器繞線上的誤差及耗時等缺點，同時此一致性的測試條件更可分析出不同試片間的差異性。

This thesis sets up the static test system to measure the magnetic properties of the silicon steel sheets. For the research, we build some common ring testers, a standard 25cm Epstein tester and an innovative structure applied to ring specimens. The test setup is used to measure silicon steel sheet properties critical for electrical motors and transformers design. The setup is capable of measuring the iron losses of silicon steel sheets under different of magnetizing waveform such as sinusoidal and Pulse-Width Modulation (PWM) waveforms. This thesis is divided into four parts: first, we build the common ring testers with three winding types and a 25cm Epstein tester with 0.5kg and 2kg specimen frames according to the ASTM standard. The test setup integrates the testers, a data acquisition card, a linear power amplifier, and a power meter into the static testing system. The second part of the thesis shows the experimental results under sinusoidal magnetizing waveforms that match with those from CSC measurement within the 50Hz~5kHz region. We also analyze the variations between different winding types. The system is able to extend the measuring bandwidth by applying induced voltage waveform control. The third part of the thesis builds a multi-function PWM inverter to enable iron loss measurement under the same operating condition as in an electric motor. The setup enables steel sheets magnetic properties measurement under non-sinusoidal excitations while maintaining the desired modulation waveforms and the carrier frequencies with different switching modes (unipolar and bipolar). Finally, this thesis proposes a new reusable ring type magnetic testing apparatus. The innovative tester permits easy exchange of the test specimens and provides a unified winding environment to eliminate any influences induced by winding irregularities. The unified testing condition then allows one to compare the more detailed and sensitive properties of different specimens.