R
[email protected]
- Jan 1, 1970
- 0
My Usenet reader is playing up so if this is a double post I
apologize:
I am experimenting with a wind turbine home built with a brushless,
permanent magnet,
three phase Fisher and Paykel washing machine motor.
To do some tests, I have used a variable resistive load and, by
manually
varying the load on the wind turbine, I have found that a 6km/h wind
can
generate 10W, a 12km/h wind can generate 80W, a 23km/h wind can
generate
640W and a 46km/h wind can generate over 5KW.
The problem is when I use batteries instead of a variable load.
At lower wind speeds, the produced voltage of the motor
is not higher than the batteries, so the turbine just spins and spins
but
does not make any useable power. The turbine only starts charging the
batteries at 20km/h winds, which is a shame as a lot of power just
flies by
without being collected. This is a battery impedance mis-match
problem.
So I think it would be very worth while designing a circuit that
doubles
triples or quadruples the voltage at lower wind speeds, so that I can
get
every last bit out of the wind.
I have looked at voltage multipliers, and since the F&P motor is three
phase, I wonder what your opinion is of this circuit right at the
bottom of
the page:
http://home.earthlink.net/~jimlux/hv/cw1.htm
I was thinking of using a microprocessor to control mosfets to select
the
optimum output voltage for the RPM of the wind turbine. Each mosfet
would be
connected to each subsequent voltage doubler point.
I am not too familiar with voltage multipliers, hence if anyone has
any
opinions on their use in this purpose, I would be very interested to
know.
Voltage ripple is not much of an issue, I am more interested in what
the
efficiency of such a circuit would be or any drawbacks that I have not
forseen.
apologize:
I am experimenting with a wind turbine home built with a brushless,
permanent magnet,
three phase Fisher and Paykel washing machine motor.
To do some tests, I have used a variable resistive load and, by
manually
varying the load on the wind turbine, I have found that a 6km/h wind
can
generate 10W, a 12km/h wind can generate 80W, a 23km/h wind can
generate
640W and a 46km/h wind can generate over 5KW.
The problem is when I use batteries instead of a variable load.
At lower wind speeds, the produced voltage of the motor
is not higher than the batteries, so the turbine just spins and spins
but
does not make any useable power. The turbine only starts charging the
batteries at 20km/h winds, which is a shame as a lot of power just
flies by
without being collected. This is a battery impedance mis-match
problem.
So I think it would be very worth while designing a circuit that
doubles
triples or quadruples the voltage at lower wind speeds, so that I can
get
every last bit out of the wind.
I have looked at voltage multipliers, and since the F&P motor is three
phase, I wonder what your opinion is of this circuit right at the
bottom of
the page:
http://home.earthlink.net/~jimlux/hv/cw1.htm
I was thinking of using a microprocessor to control mosfets to select
the
optimum output voltage for the RPM of the wind turbine. Each mosfet
would be
connected to each subsequent voltage doubler point.
I am not too familiar with voltage multipliers, hence if anyone has
any
opinions on their use in this purpose, I would be very interested to
know.
Voltage ripple is not much of an issue, I am more interested in what
the
efficiency of such a circuit would be or any drawbacks that I have not
forseen.