{"id":2820,"date":"2024-08-25T13:13:06","date_gmt":"2024-08-25T13:13:06","guid":{"rendered":"https:\/\/workhouse.sweetdishy.com\/?p=2820"},"modified":"2024-08-25T13:13:06","modified_gmt":"2024-08-25T13:13:06","slug":"star-or-wye-y-connection","status":"publish","type":"post","link":"https:\/\/workhouse.sweetdishy.com\/index.php\/2024\/08\/25\/star-or-wye-y-connection\/","title":{"rendered":"STAR OR WYE (Y) CONNECTION"},"content":{"rendered":"\n

In star or wye (Y) connections, the similar ends (either start or finish) of the three windings are connected to a common point called star or neutral point. The three line conductors are run from the remaining three free terminals called line conductors. Ordinarily, only three wires are carried to the external circuit giving three-phase, three-wire star-connected system. However, sometimes a fourth wire is carried from the star point to the external circuit, called neutral wire, giving three-phase, four-wire star-connected system.<\/p>\n\n\n\n

As shown in\u00a0Figure 8.4, the finish terminals a2<\/sub>, b2<\/sub>, and c2<\/sub>\u00a0of the three windings are connected to form a star or neutral point. From the remaining three free terminals, three conductors are run, named R, Y, and B. The current flowing through each phase is called phase current\u00a0I<\/em>ph<\/sub>and current\u00a0flowing through each line conductor is called line current IL<\/sub>. Similarly, voltage across each phase is called phase voltage (Eph<\/sub>) and voltage across two line conductors is called line voltage (EL<\/sub>).<\/p>\n\n\n\n

\"image\"\/<\/figure>\n\n\n\n

Fig. 8.4  <\/strong> (a) 3-phases connected in star (b) Star connected system<\/p>\n\n\n\n

8.9.1  Relation between Phase Voltage and Line Voltage<\/h4>\n\n\n\n

The connections are shown in Figure 8.5(a)<\/a>. Since the system is balanced, three voltages E<\/em>NR<\/sub>, E<\/em>NY<\/sub>,and E<\/em>NB<\/sub>are equal in magnitude, but displaced from one another by 120\u00b0 electrical. Their phasor diagrams are shown in Figure 8.5(b)<\/a>. The arrow heads on emfs and currents indicate the positive direction and not their actual direction at any instant.<\/p>\n\n\n\n

Now, E<\/em>NR<\/sub> = E<\/em>NY<\/sub> = E<\/em>NB<\/sub> <\/sub><\/em>= E<\/em>ph<\/sub>(in magnitude)<\/p>\n\n\n\n

\"image\"\/<\/figure>\n\n\n\n

Fig. 8.5<\/strong>  (a) Circuit representing phase and line voltages and currents in star connections (b) Phasor diagram of phase and line voltages in star connections<\/p>\n\n\n\n

It may be seen that between any two lines, there are two phase voltages.<\/p>\n\n\n\n

Tracing the loop NRYN, we get \"image\"<\/p>\n\n\n\n

or<\/p>\n\n\n\n

\"image\"\/<\/figure>\n\n\n\n

To find the vector sum of E<\/em>NY<\/sub>and \u2212E<\/em>NR<\/sub>, reverse the vector E<\/em>NR<\/sub>and add it vectorially with E<\/em>NY<\/sub>as shown in Figure 8.5(b)<\/a>.<\/p>\n\n\n\n

Therefore,<\/p>\n\n\n\n

\"image\"\/<\/figure>\n\n\n\n

or<\/p>\n\n\n\n

\"image\"\/<\/figure>\n\n\n\n

Similarly,<\/p>\n\n\n\n

\"image\"\/<\/figure>\n\n\n\n

Hence, in star connections, <\/em>line voltage = \"image\" phase voltage.<\/p>\n\n\n\n

8.9.2  Relation between Phase Current and Line Current<\/h4>\n\n\n\n

From\u00a0Figure 8.5(a), it is clear that same current flows through phase winding as well as the line conductor since line conductor is just connected in series with the phase winding.<\/p>\n\n\n\n

 <\/p>\n\n\n\n

I<\/em>R<\/sub>= I<\/em>NR<\/sub>;<\/em> I<\/em>Y<\/sub>= I<\/em>NY<\/sub>and I<\/em>B<\/sub>= I<\/em>NB<\/sub><\/p>\n\n\n\n

 <\/p>\n\n\n\n

where I<\/em>NR<\/sub>= I<\/em>NY<\/sub>= I<\/em>NB<\/sub>= I<\/em>ph<\/sub>(phase current) and I<\/em>R<\/sub>= I<\/em>Y<\/sub>= I<\/em>B<\/sub>= I<\/em>L<\/sub> <\/sub><\/em>(line current)<\/p>\n\n\n\n

Hence, in star connections, line current = phase current.<\/p>\n","protected":false},"excerpt":{"rendered":"

In star or wye (Y) connections, the similar ends (either start or finish) of the three windings are connected to a common point called star or neutral point. The three line conductors are run from the remaining three free terminals called line conductors. Ordinarily, only three wires are carried to the external circuit giving three-phase, […]<\/p>\n","protected":false},"author":1,"featured_media":2812,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[411],"tags":[],"class_list":["post-2820","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-three-phase-ac-circuits"],"jetpack_featured_media_url":"https:\/\/workhouse.sweetdishy.com\/wp-content\/uploads\/2024\/08\/ac-voltage-source.png","_links":{"self":[{"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/posts\/2820","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/comments?post=2820"}],"version-history":[{"count":1,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/posts\/2820\/revisions"}],"predecessor-version":[{"id":2821,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/posts\/2820\/revisions\/2821"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/media\/2812"}],"wp:attachment":[{"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/media?parent=2820"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/categories?post=2820"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/tags?post=2820"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}