Difference between revisions of "Lifefix"
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*[[http://www.wcmagnetics.com/catalog/highcurrent_inductor.php 85uH, Isat=17A, PN: 323-18 (WCM323 series)]] | *[[http://www.wcmagnetics.com/catalog/highcurrent_inductor.php 85uH, Isat=17A, PN: 323-18 (WCM323 series)]] | ||
*[[http://www.cooperbussmann.com/pdf/4935b080-1881-43db-b73d-e2176f2c5e73.pdf PDF 100uH, Isat=13.0A]] | *[[http://www.cooperbussmann.com/pdf/4935b080-1881-43db-b73d-e2176f2c5e73.pdf PDF 100uH, Isat=13.0A]] | ||
| − | *[[http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=M8377-ND Digikey 100uH, 14A, 18mohm]] | + | *[[http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=M8377-ND Digikey 1KHZ : 100uH, 14A, 18mohm]] |
| − | *[[http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=1539M26-ND Digikey 100uH, 14.4A, 25mohm]] | + | *[[http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=1539M26-ND Digikey 1KHZ : 100uH, 14.4A, 25mohm]] |
=Power Supplies= | =Power Supplies= | ||
[[http://www.thomasglobal.com/news/article/15970-500_watts_of_compact_power_at_72V_SPH500_7207_from_MGV/ 54V-80V, 500W DIN rail]] | [[http://www.thomasglobal.com/news/article/15970-500_watts_of_compact_power_at_72V_SPH500_7207_from_MGV/ 54V-80V, 500W DIN rail]] | ||
Revision as of 02:07, 4 August 2009
Contents
Copley supply voltage
- Peak motor input power : 25.2V * 30 amps = 756 watts
- torque advantage : 25k/7k = 3.57
- Maximum motor current = 30amps / 3.57 = 8.4amps
ir drop
- R = (450mohm + 160 mohm) * 3/4 (R of motor and inductors)
- IR = 3.4V
V=Ldi/dt
- L = (102uH + 160uH) * 3/4 = 200uH
- I=Io * sin(ft)
- f = 25krpm/60 * 2 elec cycles * 2pi = 5236 rads
- dI/dt=f * Io * cos(t) = f * Io (peak) = 5236 * 8.4 = 44e3 Amps/sec
- V = 200uH * 44e3 = 8.8V
back EMF
- EC30 speed const = 355 rpm/volt : 25000 = 70.4V
total supply
- total voltage = 70.4 + 3.4 + 8.8 = 82.6V
- max PWM = 96% (estimate) -> 86 volts needed on copley
What if only 4.2 amps at peak speed
- LdI/dt = 4.4V
- IR = 1.7V
- back EMF = 70.4VV
- total supply = 76.5/.96 = 79.7V
What if 4.2 amps at 23000 rpm
- LdI/dt = 4.05V
- IR = 1.7V
- back EMF = 64.8V
- total supply = 70.55/0.96 = 73.5V
Inductors
- [12 awg, 80uH, 50mohm air core]
- [85uH, Isat=17A, PN: 323-18 (WCM323 series)]
- [PDF 100uH, Isat=13.0A]
- [Digikey 1KHZ : 100uH, 14A, 18mohm]
- [Digikey 1KHZ : 100uH, 14.4A, 25mohm]
