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  1. Alec_t

    help with IR2110 chips

    Because a lot of voltage is dropped across the internal resistance of the coils, so power is wasted in heating up the coils. That is not the same configuration as I suggested originally. You have connected both terminals of V1 to the diodes. There is power gain, but not enough. You are not...
  2. Alec_t

    help with IR2110 chips

    At what wheel rotation rate? Are we talking real life or simulation? Is that 14V peak or RMS? How is the coil producing DC? Your fan (the inverter load) needs 15W of power to run at its rated speed. No inverter is 100% efficient; 85% is more typical. So the needed input power to an 85%...
  3. Alec_t

    help with IR2110 chips

    Exactly. But your fan is rated 15W. Allowing for inefficiencies in the inverter, you would need the generator to give you about 18W. Output voltage of a coil is proportional to rate of change of flux, hence wheel rotation rate. My sim was based on an assumed 40V peak out for a 2000 rpm speed...
  4. Alec_t

    help with IR2110 chips

    Ohm's Law. 100 Ohm load means less current draw, hence less voltage drop across the internal resistance of the coil.
  5. Alec_t

    help with IR2110 chips

    Here you go, assuming the 120 degree offset: The generated voltage using the four 54 Ohm coils arranged as two pairs depends a lot on load, as the traces below show : In practice, allowing for an ~85% efficient inverter, the power required from the generator will be ~18W, so even with the...
  6. Alec_t

    help with IR2110 chips

    The wave won't be a true sine-wave, because the coil inductance will vary as a magnet moves near it and the coil energisation is discontinuous.
  7. Alec_t

    help with IR2110 chips

    From the above pic it seems an N pole will be passing all four coils at the same time. Is that what you want? This should allow for a greater current by parallelling coils, but at the expense of greater ripple in the voltage. Isn't it usual with this type of generator to have a magnet number...
  8. Alec_t

    help with IR2110 chips

    How come, if the magnets on the back are angularly offset from those on the front, as shown in post #417? Also, the magnet polarities aren't shown.
  9. Alec_t

    help with IR2110 chips

    You could put two coils in parallel, with the same polarity, provided a magnet influences both equally at the same time.
  10. Alec_t

    help with IR2110 chips

    Because the circuit configuration uses both halves of the AC waveform and is in effect a voltage doubler. The peak voltage is 40V, the RMS is less, and the coil resistance drops voltage. I haven't forgotten. The coils aren't in parallel. The coil voltages are not in phase (they're in...
  11. Alec_t

    help with IR2110 chips

    Sadly, that's the case, unless you can source bigger coils with lower resistance but a similar number of turns. Driving a 15W load from a 30V supply needs 0.5A current, but 0.5A would drop 25V across a 50 Ohm coil resistance.
  12. Alec_t

    help with IR2110 chips

    Yes. Hold down the Ctrl key and left-click the title of the blue trace. You'll get average Wattage in a drop-down box.
  13. Alec_t

    help with IR2110 chips

    You reduced the internal resistance of your voltage sources V1-V4 from 54 ohms to zero! All those Ohms were starving the rest of the circuit of current. But now the modelled motor is dissipating about 65W.
  14. Alec_t

    help with IR2110 chips

    Trial and error in a sim, with the 'motor' driven by a 50Hz sine-wave. Nope. Nope. Lamination dimensions and permeability, plus the way the coil is wound (layers, size, wire gauge) all affect inductance. Yes.
  15. Alec_t

    PWM on 12volt winch?

    Why not simply use a geared AC motor with VFD control, rather than the winch?
  16. Alec_t

    help with IR2110 chips

    Judging by this article, accurate simulation of a shaded-pole motor would be tricky. I'd just use an inductor with appropriate inductance and resistance parameters. Edit: Try 1.3H, 50 Ohms. These give about 15W on a 230V rms 50Hz supply, but may be some way off realistic values.
  17. Alec_t

    help with IR2110 chips

    The more parameters you know and apply the closer the sim result to the real world. But guestimates should put you in the ball-park.
  18. Alec_t

    PWM on 12volt winch?

    More likely the winch motor would stall or cut out, if the chain has been properly specified. With half a ton of flywheel attached the inertial load could keep the motor nearly stalled for quite a while. Per the posted spec, the winch already has a manual clutch.
  19. Alec_t

    help with IR2110 chips

    The inductance ratio in the Spice program will affect the output voltage in the simulation. You don't (if the tranny spec doesn't give it), but as I said in post #366, "googling for properties of a similar size transformer may give some idea".
  20. Alec_t

    PWM on 12volt winch?

    Couldn't you simply pull the load via a strong coil spring to avoid the initial jerk? Are you sure the winch doesn't already have a soft-start feature?
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