Hi. I have been following your circuit tips for a little while. Very helpful and informative!
I was wondering if you can help me out.
This is the deal. I have a beautiful recumbent exercise bike I
inherited from my dad. Its a TRUE PS/100. It has a three phase induction
AC motor. 250watts at 1amp.
I also have a small solar system.
5 X 38wah Lithium Ion Batteries 12V in parallel. They are hooked up to
two 245 watt 10amp (each) Poly Panels. The solar system works
great…getting 18-19amps at peak sun…more than enough to charge the
Now..on cloudy or rainy days..and obviously at night I
am not getting any power into my lithium battery bank. So…. here’s
the question…. I have wanted to utilize my exercise bike to install a
bridge rectifier..(which I did)…three phase AC to single phase
DC…the problem is…its still too much voltage to charge my 12 volt
battery bank with…. how can I step down the voltage to 24volts (from
@150-200 Rectified DC) to lessen the Back EMF coming into the bike which
makes it difficult to peddle…and lower the voltage so I don’t blow the
batteries??… What type of circuit do you suggest? Resistors? 400volt
caps? a transistor perhaps?? I’m not formally trained in circuit..design.
Please help! Thanks!
Initially it appeared to me that the request was regarding operating the bike from alternative source but after reading it the second time I realized that actually it’s regarding using the exercise bike for charging batteries by generating electricity from the bike motor.
The easiest way to use a treadmill as a battery charger is by reducing its voltage through a shunt regulator circuit.
I have already discussed a few shunt regulator circuits in this website, which can be viewed through the following relevant links: