"Transluctance" conveys the Transfer (or shift) in reluctance of a rotating magnetic field (RMF) disposed of a prime number of equally distributed coils via excitation shift of one only coil at a time. This principle can be described as a magnetic circuit disposed of an equal distribution of a prime number of smaller magnetic circuits (excited by coils) arranged to form a neutral position spanning the arc length of one coil.
When magnetically coupled to the centrally positioned rotor, said rotating magnetic field results in the mechanical counter-rotation of the rotor at HALF the RMF period. This unique feature allows for the combination of high pole and high phase count within a small frame. Rotor topologies include:
1) Permanent Magnet [PM]
2) Switched Reluctance [SR]
4) Separately Excited Synchronous
This arrangement is ideal for intermittent applications such as:
1) tidal power
2) VAWT and HAWT
As a small change in movement generates a high number of pulses converted to V.D.C. output with a crest factor of 1. This eliminates the need for back to back conversion conveying D.C. directly to the inverter instead of rectifying vcariable frequency V.A.C. to V.D.C. then inverting back to 60 hz V.A.C via D.C. link. Also, high voltage crest factor allows for HVDC transmission using a D.C. to D.C. boost converter from coastal areas to load centers.
By way of comparison Nikola Tesla's 3 phase a.c. machine had a pulse (or peak) count of 6 per cycle.
So…given Tesla's 2 pole machine spinning at 3600 rpm -
RMF Frequency = Synchronous Speed (Ns) or Rotor(RPM) x Poles/120.
e.g. 60 hz = 3600 rpm x 2 poles / 120
Pulse count can be increased by increasing either the pole count or the number of phases however physical size limits increasing both pole and phase count at the same time.
Transluctance disposes a prime number coil (or phase) distribution allowing for the increase of pole and phase count at the same time in a small frame size.
Transluctance Phase Freq can now be explained by:
F = Ns x Poles / 60 so therefore -
Given a 2-pole machine with 5 coils spinning at 3600 rpm as illustrated in the 2 pole 5 coil drawing
Phase cycle frequency is given by - 120 hz = 3600 x 2 / 60 (twice that of Tesla's machine)!
with a pulse count of 5 coils (10 slot) x 2 poles x 60 = 600 pulses/sec or 10 pulses/rev.
Increasing the pole count to 4 poles with 13 coils spinning at 3600 rpm as illustrated in the 4-pole, 13 coil drawing yields a step resolution of 6.93 degrees at a phase cycle frequency of:
- 240 hz = 3600 x 4 / 60
With a pulse count = 13 coils (26 slot) x 4-poles x 60 = 3120 pulses / sec
Increasing the pole count to 14 poles with 31 coils spinning at 3600 rpm
Phase cycle frequency = 840 hz = 3600 x 14
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