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In this dissertation, the author proposed two control methods for starting
induction motors with better transient performance. For the
squirrel-cage-rotor type induction motors, solid-state soft-starter is
usedand a new control strategy (called consine-control) is introduced to
regulate the output voltage of the ac voltage controller. For the
woundrotor induction motors, an external chopper-controlled resistor is
added onto the rotor circuit to adjust the rotor resistance during
starting periods.
In order to simulate the transient characteristics of induction machines,
a hybrid model has been proposed to retain the advantages of both
direct-phase model and d-q axis model when power converter is introduced
in either stator or rotor circuit. The proposed starting methods are
simulated by using this hybrid model. The satisfactory resule are obtained
from both computer simulations and experimental tests, and the hybrid
model is proven to be the most convenient dynamic model for such
applications.
感應電動機為目前工業應用最廣泛的電動機械，然而，其啟動斬態一直是令人困擾的
問題。本文旨在探討感應電動機之啟動暫態特性，提出控制方法。
對於鼠籠式轉子感應機，本文提出一種新的餘弦控制方式，以調變交流相位控制器之
輸出電壓。較之現今所使用之方法，此控制方式可以較小之有效電流產生較大之平均
轉矩，在較短時間內將電動機啟動完成。對於繞線式轉子感應機，本文提出二種啟動
方式：〈一〉限電流啟動，〈二〉最大轉矩啟動，以外加截波器電路控制轉子之等效
電阻，將電動機快速平滑地啟動。
為了探討感應機之動態特性，作者結合直接相模型和交直軸模型，兼採兩者之優點，
提出一種混合式之動態模型。當定子或轉子介入電力電子電路時，此一混合模型可以
避免費時繁複之運算，並可獲得所欲得知之實際電壓和電流，用以偵測電子開關元件
之換向動作。
本文利用此混合動態模型模擬前述控制方式之暫態，探討其在各種負載狀態下之啟動
特性，並以實驗證實之。
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