理解原线圈电流与电压的相位关系  

Understanding the phase relation between voltage and current of the primary coil

作　　者：涂泓[1] 方伟[1] TU Hong;FANG Wei(Mathematics and Science College, Shanghai Normal University, Shanghai 200234, China)

机构地区：[1]上海师范大学数理学院,上海200234

出　　处：《大学物理》2019年第4期4-7,共4页College Physics

摘　　要：当理想变压器连接纯电阻负载时,原线圈的电压与电流是同相的,但不少初学者对于这一点存有误解和困惑,因此在用瞬时值分析时容易出现疏漏,得出两者相位差等于π/2的错误结论.本文用矢量法分析理想变压器各物理量之间的相位关系,并给出正确的瞬时值分析过程,从而指出上述错误结论的来源.When an ideal transformer is connected to a pure resistive load, the voltage and the current of the primary coil are in phase. However, many beginners are confused about this point. As a result, possible errors and omissions in instantaneous value analyses can lead to a clearly wrong conclusion that there is a phase difference of π/2 between the voltage and the current of the primary coil. In this paper, the phase relations between the physical quantities of an ideal transformer are analyzed using vector diagrams. The correct instantaneous value analysis is also given, so that the main reason of the wrong conclusion is pointed out.

关 键 词：变压器 相位 磁通 空载电流 

分 类 号：O441.1[理学—电磁学]