Jamie wrote:

Yes, 2 phase of 90 degree's still exist, so why is that ok but 180
degree's isn't?

Because the decomposition of two 90º phasor contains an imaginary part.
Without a real part AND an imaginary part, no distinct phases could be
constructed or generated.

There is no imaginary part in the decomposition of two 180º apart vectors,
and, therefore there is no way to construct other phases (phasors).

Sorry, you need to know phasors to understand this principle.

--
Mark Cross
If Linux doesn't have the solution, you have the wrong problem.