"抽头转换开关" can be translated into English as "tap-changer switch" or simply "tap changer" (when the context makes it clear that it refers to the switching device).
Tap-changer switch emphasizes the switching function of the device used for changing taps.
Tap changer is a more common and concise term in the electrical engineering field, referring to the entire mechanism or device for changing taps, which inherently includes the switching function.
In most technical contexts, especially in electrical engineering and power systems, "tap changer" is widely recognized and used.