So back to this little gem of a brain bleed waiting to happen .
Precision Microdrives provides a selection of methods for stabilising DC motor speed, without the use of external sensors
www.precisionmicrodrives.com
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Solving for
I5:5=ℎ(ℎ+1)×2ℎ(+2)+(ℎ+1)2×
So the output voltage is equal to:=5×=ℎ(ℎ+1)××2ℎ(+2)+(ℎ+1)2××
And for no load operation:=ℎℎ+1××
The output voltage between points
A and
B is independent from power supply and motor current, both with no load and in loaded operation. It is dependent on
h, and when increased the output voltage is also increased.
As mentioned previously, the armature resistance will change with temperature – unbalancing the bridge and affecting the output
Vrpm. The bridge should be tuned with the motor is at operating temperature to minimize this effect.
This method of speed stabilization was a popular solution for governor rotor speed controllers found in tape recorders using analogue electronics. In the era of the tape recorder, many companies made chips for DC motor control to ensure the tape moved at a constant speed. This was an interesting solution because it operated linearly and didn’t produce any noise, like PWM based controllers.
[/~snip]