1. PARALLEL OPERATION OF SINGLE PHASE TRANSFORMER
Mehran University Of Engineering & Technology, SZAB Khairpur Mirs Campus
PARALLEL OPERATION OF SINGLE PHASE TRANSFORMER
ENGR. AHSANULLAH MEMON LECTURER DEPARTMENT OF ELECTRICAL ENGINEERING MUCET KHAIRPUR MIRS

2. INTRODUCTION
The transformers are connected in parallel when load on one of the transformers is more than its capacity.
Two transformers are said to be connected in parallel if the primary windings are connected to supply busbars and secondary windings are connected to load busbars.
The reliability is increased with parallel operation than to have single larger unit.
The cost associated with maintaining the spares is less when two transformers are connected in parallel.

3. Conditions for Parallel Operation

4. CONDITION (I)

5. CONDITION (II)

7. CONDITION (III)

8. CONDITION(IV)
If the reactance/resistance ratios of the two transformers are not equal, the power factor of the load supplied by the transformers will not be equal.
In other words, one transformer will be operating with a higher and the other with a lower power factor than that of the load.