继电保护原理与应用(第三版)3.1-3.5(18)

相反，相位旋转或相序是指逆时针旋转时相量出现的顺序。今天的标准顺序是：a，b，c；a，b，c；1，2，3；或者在某些区域r，s，t。在图3.3b中，顺序是a，b，c，如图所示。IEEE字典（IEEE 100）仅定义相序；因此，这是首选。然而，相位旋转已经使用了很多年，并且仍在实践中。
Not all power systems operate with phase sequence a, b, c, or its equivalent. There are several large electric utilities in the United States that operate with a, c, b phase sequence. Occasionally, this sequence is used throughout the system; for others, one voltage level may be a, b, c, and another voltage level, a, c, b. The specific phase sequence is only a name designation that was established arbitrarily early in the history of a company, and it is difficult to change after many years of operation.
并非所有的电力系统都以相序a、b、c或其等效物运行。美国有几家大型电力公司采用a、c、b相序运行。有时，该序列在整个系统中使用；对于其他系统，一个电压等级可以是a、b、c，另一个电压等级可以是a、c、b。特定的相序只是在公司历史早期任意建立的名称名称，在运行多年后很难改变。
Knowledge of the existing phase sequence is very important in threephase connections of relays and other equipment; therefore, it should be clearly indicated on the drawings and information documents. This is especially true if it is not a, b, c. The connections from a, b, c to a, c, b or vice versa can generally be made by completely interchanging phases b and c for both the equipment and the connections.