Series and Parallel Connection of Coupled Coils
There are four possible ways of connecting coil in series and parallel. We will analyze each case one by one.
Case-I : Series Aiding Connection
Figure (a) shows the series connection of two coupled inductors with self inductance L1, L2 and mutual inductance M. The currents in both inductors at any instant of time are in same direction relative to the like terminals. This is called series aiding connection. To find out total inductance in this case, consider the circuit given in the figure (b). Writing KVL in the loop, by taking mutual voltage into account.
Case-II : Series Opposing Connection
Figure (c) given below shows the series connection of two coupled inductors with self inductance L1, L2 and mutual inductance M. The currents in both inductors at any instant of time are in opposite direction relative to the like terminals. This is called series opposing connection. To find out a total inductance in this case, consider the circuit given in the figure (d). Writing KVL in the loop, by taking mutual voltage into account.
Case-III : Parallel Connection of Coupled Coils
Figure shows the parallel connection of the coupled coils L1 and L2 having mutual inductance M. The equivalent inductance for the circuit shown below in figure (e) is
Case-IV : Parallel Connection of Coupled Coils
Figure (f) shows the parallel connection of the coupled coils L1 and L2 having mutual inductance M. The equivalent inductance for the circuit shown below in figure (f) is
