and some formulas for calculating electric motor speed
Raising voltage on a DC electric engine quite often works, But two things can truly harm it. 1) An engine running on more voltage will run more sizzling, Don't give it a chance to get so hot that your wire windings begin to notice (smoldering varnish) extremely hindering. 2) An engine on considerably more voltage can eat it's brushes on the commutator speedier then it can get hot. Just piece of information you get is a few sounds and the welder like arcing on the off chance that you can see into the brush hole. Likewise seems like you are both battery and engine constrained. When you change to a higher rigging and the engine velocity does not move go down close to it's past rate before long.
Basic DC motors work like this, The motor rotation generates a back EMF so the current is the voltage difference divided by the motor resistance. The current varies as the torque. So the stalled torque (zero EMF) varies as the input voltage divided by the motor resistance. But given no load, the motor will spin up to the point where the EMF matches the input voltage and current falls towards zero. The back EMF is the product of the speed and the field strength, so if you reduce the magnetic field, the motor will have to turn faster to generate the same EMF. Normally this would require more current but if you reduced the load as well, it could run faster without increasing the current.
AC motors usually have the following on the nameplate: Rated output power – Pr (kilowatts – kW or Horsepower – Hp) Rated speed – nr (revolutions per minute – RPM) Rated voltage – Vr (volts – V) Rated frequency – fr (hertz – Hz) Rated current – Ir (amperes – A) Other parameters (not on the nameplate): Rated torque – Mr (Newton meters – Nm or pounds feet – lbs-ft) Mr=9550xPr/nr for Mr in Nm Pr in kW Mr=5252xPr/nr for Mr in Hp Pr in lbs-ft Number of poles – p (always an even number, only north/south pairs are possible) With 3-phase induction motors, speed can be increased or decreased by changing the frequency: Speed, n = 120f/p To have available torque remain constant at M = Mr without current exceeding rated current, voltage must be increased or decreased with frequency change such that V = f x Vr/fr. Speed increase is limited by the motor’s ability to tolerate the electrical stress due to increased voltage and the mechanical stress due to increased speed above the rated values. If the frequency is increased above the rated value without increasing the voltage, the available torque will be reduced. Up to about 50% above rated speed, the available torque is approximately the torque that will produce the rated output power. Under some load conditions, some types of single phase motors can be controlled in the same way to a more limited extent. Under some load conditions, with some types of single phase and three phase motors voltage reduction can be used to reduce speed to a limited extent.
