Window Motor Doubles Voltage At The Power Supply [Overunity ?]

[DadHav]

OK Guys. Let me fill you in on what tests I made. I have a few days to experiment before leaving again. I put a 37,000 mfd cap across the power supply terminals. I have a 1 amp diode between the supply and the motor circuit on the plus side. I have a 37,000 mfd 40 volt cap across the inputs of the circuit boare after the diode.
The circuit is the standard full wave sequential bipolar. only one trigger is being used the other is not connected. There is a switch on the board to return the voltage from the bridge back to the input or switch it to an external plug. the motor is 400 ft 400 turns trifiler; two triggers with #32 and one power coil #23, six magnets; two pound steel rotor.

OK with the diode in the circuit the motor runs more like it was on a battery. Under normal running conditions the the motor likes 20 -40 ma while at the 20 volt range. If I tune the circuit to run at 100 - 200 ma the motor has surprising torque.
First test: Power supply voltage 20 v @ 20 ma; Motor RPM=1750; Voltage on PS cap=20 volts; Voltage on circuit input cap=19.75 (normal IMO) Note the return switch is in the external position. A 37,000 mfd cap on the external output charges to 50 volts with some authority considering only drawing 20 ma; a 1.0 mfd 200 volt cap will charge to 75 volts instantly.
Second test: I disconnected the capacitor on the input of the circuit board after the diode; The RPM increased to 2112 RPM; The voltage on the power supply cap was 20 volts; the current draw went to 30 ma; The voltage measurement after the diode was 35.7 volts.
Third test: I placed the 1.0 mfd cap after the diode across the circuit board input; The motor increased in speed to 2670 RPM; the capacitor on the power supply was 20 volts; the current went to 40 ma on the power supply.
The motor in this combination ran smoother than ever before. It also ran from the capacitor on the power supply for a few minutes before stopping when the supply was turned off. I tried the same tests on a different make supply and they came out the same, although I didn't check the ma draw yet while on another sorce.
Maybe a few scope shots will be helpful. I haven't tried a picture yet. Let's see what happens. In case they don't work, what I saw was 20 volts dead solid before the diode, but after the diode there was quite a nice signal going an additional 30 to 40 volts above the 20 volt base line. This must have been what was getting back into the power supply to cause the anomaly. The pattern changed considerably with the small capacitor on it.

[dankie]

Very unusual scopeshots .

The drop time seems to be going backwards . And what is that double bump ?

[DadHav]

Keep in mind the scope is on the input side of the full wave circuit. Are you thinking about an h wave like the SSG circuit?
John

[gyulasun]

Hi John,

Many thanks for performing and sharing these tests. I do think now that the PS you use was malfunctioning whenever the output pulses or the rest of them via the diode bridge managed to foul the control circuits of the PS (when your turbo switch was on) and this manifested in an increased output voltage.
And Magluvin was right in saying the back emf (and if I may add the induced voltages at the switch off instants) were the main cause of the output pulses and these went back into the PS unavoidably via the switch.  The series diode (a one way switch) blocks the return of the pulses to the PS or any other source.  In case of operating the motor from a battery, there is no control circuit in it, so no problem from the created pulses, they dissipate in the battery.

I would ask and suggest two things.  In your test #1 with either the 37000uF or 1uF capacitor on the external output (turbo switch is off), what happens to the motor 20mA running current when you place a few kiloOhm resistor across the external output as a load? Will the overall 20mA motor current change and in what direction? 
My suggestion would be to your test #3 when you found that with only a 1uF capacitor after the diode you got the biggest rpm and smooth operation.  I think you could experiment here with a capacitor bank to find the "sweet" point i.e. the best cap value for the whole setup. This would involve a certain resonance case and a match between the rpm and your coil + best capacitor parallel resonant circuit combination.  This sounds like Hector's rotoverter circuit and I think it would be like that. The only drawback is when you load the motor shaft the resonant condition detunes and it ought to be retuned to the load's need again.

Thanks, Gyula

OK Guys. Let me fill you in on what tests I made. I have a few days to experiment before leaving again. I put a 37,000 mfd cap across the power supply terminals. I have a 1 amp diode between the supply and the motor circuit on the plus side. I have a 37,000 mfd 40 volt cap across the inputs of the circuit boare after the diode.
The circuit is the standard full wave sequential bipolar. only one trigger is being used the other is not connected. There is a switch on the board to return the voltage from the bridge back to the input or switch it to an external plug. the motor is 400 ft 400 turns trifiler; two triggers with #32 and one power coil #23, six magnets; two pound steel rotor.

OK with the diode in the circuit the motor runs more like it was on a battery. Under normal running conditions the the motor likes 20 -40 ma while at the 20 volt range. If I tune the circuit to run at 100 - 200 ma the motor has surprising torque.
First test: Power supply voltage 20 v @ 20 ma; Motor RPM=1750; Voltage on PS cap=20 volts; Voltage on circuit input cap=19.75 (normal IMO) Note the return switch is in the external position. A 37,000 mfd cap on the external output charges to 50 volts with some authority considering only drawing 20 ma; a 1.0 mfd 200 volt cap will charge to 75 volts instantly.
Second test: I disconnected the capacitor on the input of the circuit board after the diode; The RPM increased to 2112 RPM; The voltage on the power supply cap was 20 volts; the current draw went to 30 ma; The voltage measurement after the diode was 35.7 volts.
Third test: I placed the 1.0 mfd cap after the diode across the circuit board input; The motor increased in speed to 2670 RPM; the capacitor on the power supply was 20 volts; the current went to 40 ma on the power supply.
The motor in this combination ran smoother than ever before. It also ran from the capacitor on the power supply for a few minutes before stopping when the supply was turned off. I tried the same tests on a different make supply and they came out the same, although I didn't check the ma draw yet while on another sorce.
Maybe a few scope shots will be helpful. I haven't tried a picture yet. Let's see what happens. In case they don't work, what I saw was 20 volts dead solid before the diode, but after the diode there was quite a nice signal going an additional 30 to 40 volts above the 20 volt base line. This must have been what was getting back into the power supply to cause the anomaly. The pattern changed considerably with the small capacitor on it.

[Magluvin]

Ok guys, Just uploaded a vid with a funtional 2nd stage running off of the 1st stage bemf, and charging an old 12v 7ah bat off of the 2nd stage bemf.
http://www.youtube.com/watch?v=nXxvAQ_mdUk

I am letting the battery charge to see where it comes up to.
I am very happy with this setup. =]

Magluvin