Different ends of mesh or delta connection are connected together at the end points of 3 phase windings. As per this statement, at the end point of one phase which can be seen as its starting point is connected to the other point of the different phase known as the finishing end.
This diagram or figure showcases mesh or delta connection.
As per this figure, in order to form one close mesh, 3 windings are connected in a sequence or series. To highlight the leads in an outward direction, which is taken as positive, those 3 leads are taken into consideration (showcased via their junction).
Relationship between phase currents and line currents
From the above diagram, it is clear that phase current is the reason where the vector difference gives out the resultant as line current. In case of phase current, the concerned aspect related to 2 phases.
So, its equation can be relayed as,
So, now on the basis of the assumption where delta connected network is concerned, we will consider this system to be balanced. Therefore, in each of these windings, phase current is equivalent, and its equation is highlighted as,
This is achieved with the help of this figure (below) and the angular difference (phase difference) between 2 phase current -IRB and IYR. This difference is of 60 electric degrees.
Relationship between phase voltages and line voltages
If we see through the first diagram, it is clearly depicted that in the line outers between any pairs only one phase is linked in a mesh or delta connected system. Hence, the potential difference that is between line outers is equivalent to phase voltage. So,
Phase voltage (Eph) = Line voltage(EL)
With respect to line values, the expression for power in accordance with the above figure,
Phase power factor angle= Ф
Important points regarding mesh or delta connected system
- Line currents are seen to be times phase current
- Phase voltages are equivalent to line voltages.
- In case of line currents, they lag behind their individual phase current by 30°.
- The angular distance between line currents is seen to be 120°.
- If we see the resultante.m.f. ina balanced system, it is zero in a closed circuit. Its equation can be highlighted by,
EBR +EYB +ERY = 0.
Consideration for this e.m.f is based on primary colors.
- As in accordance with star system, angle between line voltages and line currents is (Ф ± 30°)
Therefore, in the mesh system, there will not be any circulating current if the linked aspect is no-load to that specific line.