panalog9
Full Member level 2
propeller clock design
Hi -
Short question is, what is the best way to get power to a rotating part, like on a propeller clock ?
A good method seems to be to use an air-core transformer. The primary is stationary, and transfers power to the secondary which is mounted on the rotating part.
See these links for some samples :
**broken link removed**
**broken link removed**
But what is the best/most efficient way to do this ? There are two basic methods :
1) Transformer. Coils are wound in phase, and power is sent over to secondary while primary is conducting. Two diodes and capacitor or two serve to smooth the power. Input waveform should be a nice clean sinewave.
2) Flyback transformer. Coils are wound out of phase, and power is only transferred when the primary STOPS conducting. The collapsing magnetic field generates the current in the secondary. Again, diode(s) and caps to smooth the power. Input waveform should be a ramp, rising smoothly, then shutting off sharply.
This is the theory at least - is this correct ? I've played around with it a bit, but not with much luck. I can't seem to get enough efficiency - not enough power to get to the rotating secondary.
-pana
Hi -
Short question is, what is the best way to get power to a rotating part, like on a propeller clock ?
A good method seems to be to use an air-core transformer. The primary is stationary, and transfers power to the secondary which is mounted on the rotating part.
See these links for some samples :
**broken link removed**
**broken link removed**
But what is the best/most efficient way to do this ? There are two basic methods :
1) Transformer. Coils are wound in phase, and power is sent over to secondary while primary is conducting. Two diodes and capacitor or two serve to smooth the power. Input waveform should be a nice clean sinewave.
2) Flyback transformer. Coils are wound out of phase, and power is only transferred when the primary STOPS conducting. The collapsing magnetic field generates the current in the secondary. Again, diode(s) and caps to smooth the power. Input waveform should be a ramp, rising smoothly, then shutting off sharply.
This is the theory at least - is this correct ? I've played around with it a bit, but not with much luck. I can't seem to get enough efficiency - not enough power to get to the rotating secondary.
-pana