In this submission, we address the possibility of using tandem synchronous machines in a stabilized slipped-pole condition as a free energy prime mover for driving a third synchronous generator feeding the grid.

When I was an electrical engineering student in machines class, one of the students asked, "What happens when a synchronous machine slips a pole?" The answer was something like, "large torque pulsations occur, huge transients flow, and breakers trip..."

This was clearly an unstable slipped-pole condition whereas this document claims to investigate a stabilized slipped-pole condition. The questions arise "How do we achieve that, and what does it look like?"

The answer involves connecting two synchronous
machines by one solid shaft with the desired slip-angle appearing
between the spinning open-circuit voltages. Then the phases are
connected together A to A', B to B', and C to C' where the primed
open-circuit voltages of one machine lag the unprimed voltages of
the other by 60 degrees.

If interested parties
construct the phasor diagrams for current and voltage and calculate the
complex power for each machine, I believe you will find a net real
positive power (Pnet) for both machines in sum, and thus a net positive
driving torque, which can be used to drive the third generator feeding
and synchronized to the grid.