【正文】 n the device like the effects of saturation, so for an understanding of internal behaviour . There are two ways of looking at the equivalent circuit: (a) viewed from the primary as a sink but the referred load impedance connected across 39。 similarly 139。39。 221? . Consequently, 22212 )/(39。 alternatively, 221011 NININI ?? . At full load, the current 0I is only about 5% of the fullload current and so 1I is nearly equal to 122 /NNI . Because in mind that 2121 / NNEE ? , the input kVA which is approximately 11IE is also approximately equal to the output kVA, 22IE . The physical current has increased, and with in the primary leakage flux to which it is proportional. The total flux linking the primary , 111 ??????? mp , is shown unchanged because the total back .,（ dtdNE /111 ?? ） is still equal and opposite to 1V . However, there has been a redistribution of flux and the mutual ponent has fallen due to the increase of 1? with 1I . Although the change is small, the secondary demand could not be met without a mutual flux and . alteration to permit primary current to change. The flux s? linking the secondary winding has been further reduced by the establishment of secondary leakage flux due to 2I , and this opposes m? . Although m? and 2? are 5 indicated separately , they bine to one resultant in the core which will be downwards at the instant shown. Thus the secondary terminal voltage is reduced to dtdNV S /22 ??? which can be considered in two ponents, . dtdNdtdNV m // 2222 ????? or vectorially 2222 IjXEV ?? . As for the primary, 2? is responsible for a substantially constant secondary leakage inductance 222222 / ??? NiN . It will be noticed that the primary leakage flux is responsible for part of the change in the secondary terminal voltage due to its effects on the mutual flux. The two leakage fluxes are closely related。以此為分析基礎(chǔ)的電路會擁有一個既產(chǎn)生電壓大小的變化，也產(chǎn)生相位移的匝比，其阻抗也會與繞組的阻抗不同。 如果將激磁支路移至一次繞組端口，引起的誤差很小，但一些不合理的現(xiàn)象又會發(fā)生。2 RR ? ， 1239。2R ， 39。 類似地，與 222XI 成比例的漏磁場的磁場儲能 )2/1( 2LI ，求出后驗證與 39。 RNNR ? ， 22212 )/(39。 對于電流，由于對一次側(cè)作用的安匝數(shù)必須保持不變，因此 221222 39。在周期性交變中，有一次側(cè)漏磁通為零的瞬時，也有二次側(cè)漏磁通為零的瞬時，還有它們處于同一方向的瞬時。 如果我們討論一個足夠低的超前功率因數(shù)，二次側(cè)總磁通和互感磁通都會增加，從而使得二次側(cè)端電壓隨負載增加而升高。然而此時卻存在磁通的重新分配，由于 1? 隨 1I 的增加而增加，互感磁通分量已經(jīng)減小。增加的一次側(cè)電流和磁勢近似平衡了全部二次側(cè)磁勢。現(xiàn)在，我們要討論一種滯后功率因數(shù)。記住 2121 / NNEE ? ，近似等于 11IE 的輸入容量也就近似等于輸出容量 22IE 。與一次側(cè)漏磁通一樣， 2? 的作用也用一個大體為常數(shù)的漏電感 222222 / ??? NiN 來表征。 從上述圖中，還應(yīng)得出兩點：首先，為方便起見已假設(shè)匝數(shù)比為 1，這樣可使 39。因此，二次側(cè)繞組可用任意個在一次側(cè)產(chǎn)生2 相同匝數(shù) 1N 的等效繞組是方便的。/39。 39。 IENNINNEIEk V A ???? 。值得注意的是，對于一臺實際的變壓器， 239。當在電路中選擇了適當?shù)膮?shù)時，在一、二次側(cè)兩端測得的變壓器運行情況與在該電路相應(yīng)端所測得的請況是完全一致的。這對于高電壓和頻率超過 100Hz的情形是很重要的。 在上述兩種情況下，參數(shù)都可折算到二次繞組，這樣可 減小計算時間。39。XI will be found to check as 39。 . 239。2V ,or (b) viewed from the secondary as a source of constant voltage 1V with internal drops