Figure 3-36B.Three-legged, saturable-core reactor. SECOND HALF CYCLE
Another approach to solving the problem of load flux affecting control flux is shown in figure 3-37.
Figure 3-37 shows a toroidal saturable-core reactor. The shape of these cores is a toroid (donut shape).
The windings are wound around the cores so that the load flux aids the control flux in one core and
opposes the control flux in the other core.
During the first half cycle, the flux aids in the left core and opposes in the right core, as shown in
figure 3-37, view (A). During the second half cycle, the flux opposes in the left core and aids in the right
core, as shown in view (B). Regardless of the amount of load flux or polarity of the load voltage, there is
no net effect of load flux on control flux.
Figure 3-37A.Toroidal saturable-core reactor. FIRST HALF CYCLE