| 词条 | Shading coil |
| 释义 |
A shading coil or Shading ring (Also called Frager spire or Frager coil) is a single (or a few) turn of electrical conductor (usually copper or aluminum) located in the face of the magnet assembly or armature. The main alternating magnetic flux induces currents in the Frager coil. So, these induced currents create an auxiliary magnetic flux. This auxiliary flux is out of phase from the main flux[1]. The property of property allows the armature sealed-in when the main flux falls to zero (e. 100 (or 120) times / second with 50 (or 60) cycles AC). Without this shading ring, the armature would tend to open each time the main flux goes through zero and create noise, heat and mechanical damages on the magnet faces (e.g. reducing the bouncing[3] of relay or power contacts and the chatter)[4] Shaded-pole AC motorsA Shaded Pole motor is an AC single phase induction motor. The auxiliary winding, is composed of a copper ring, called a shading ring (or shading coil when more shorted turns)[5]. Shaded-pole motors are provided with a main winding connected to the single-phase electric supply. In addition, that kind of AC motors have a permanently short-circuited winding, known as a shading coil and located ahead of the main winding in the direction of rotation. This shading coil consists of one (e.g. shading ring) or more (e.g. shading coil) shorted turns. The shading coil allows to delay the establishment of magnetic flux in the region that it encircles and producing thereby a small component of rotating field at standstill[6]. References1. ^{{cite web|url=https://www.researchgate.net/figure/Sketch-of-the-contactors-electromagnet-dimensions-in-centimeter-Not-to-scale_fig2_259577477|title=Figure 2. Sketch of the contactor's electromagnet, dimensions in...|website=ResearchGate}} 2. ^{{cite web|url=https://prod.cheggstudy.prod2.cheggnet.com/homework-help/explain-shading-coil-ac-contactor-reduces-chatter-chapter-13-problem-2rq-solution-9780130612106-exc|title=Chegg.com|website=prod.cheggstudy.prod2.cheggnet.com}} 3. ^{{cite book|chapter-url=https://www.researchgate.net/publication/224355001|chapter=Design of Shading Coils for Minimizing the Contact Bouncing of AC Contactors|doi=10.1109/HOLM.2008.ECP.34|title=2008 Proceedings of the 54th IEEE Holm Conference on Electrical Contacts|pages=130–136|year=2008|last1=Riba|first1=J. R.|last2=Espinosa|first2=A. G.|last3=Cusido|first3=J.|last4=Ortega|first4=J. A.|last5=Romeral|first5=L.|isbn=978-1-4244-1901-2}} 4. ^https://cr4.globalspec.com/thread/56783/Shading-Ring 5. ^{{cite web|url=https://www.johnsonelectric.com/zh/resources-for-engineers/ac-motors/principle-of-operation|title=Principle of Operation - 德昌电机|website=www.johnsonelectric.com}} 6. ^{{cite web|url=https://www.britannica.com/technology/electric-motor|title=Electric motor - Capacitor induction motor|website=Encyclopedia Britannica}} External links{{Commons category|AC motors}}
4 : AC motors|Electromagnetic components|Power engineering|Relays |
| 随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。