Recent content by ramox3

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    Firing angle in rectifiers and inverters.

    but what is the relevant line voltage for the inverter? isn't it the same?
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    Firing angle in rectifiers and inverters.

    here's the figure :D http://imageshack.us/photo/my-images/69/figure3t.png
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    How do I solve 31 = (47.872 L θ +90˚)

    How do I solve for theta: 31 = (47.872 L θ +90˚)
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    Firing angle in rectifiers and inverters.

    Homework Statement Hello everyone I am a newbie to electrical engineering, I have this problem I've been strugling with, no textbook seems to cover this problem..A three-phase, 440-V, generator delivers 5400W of active power through two recti-fies, A and B, into a three-phase, 230-V, line as...
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    How do I calculate the power factor of a 3 phase synchronous generator?

    When I have the Vphase (254 V) S phase (6.2KVA) and I (24A) ? Help !
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    Firing angle in rectifiers and inverters.

    Hello everyone I am a newbie to electrical engineering, I have this problem I've been strugling with, no textbook seems to cover this problem..A three-phase, 440-V, generator delivers 5400W of active power through two recti-fies, A and B, into a three-phase, 230-V, line as shown in Figure 3...
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    Calculating Armature Current from Active & Reactive Power & Voltage

    so what can I say about the value of the current in the armature?
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    Calculating Armature Current from Active & Reactive Power & Voltage

    How do calculate the current when I have the active power and reactive power and voltage? A single-phase, full-wave controlled bridge rectifier supplies a permanent magnet dc motor. The rectifier is connected to a 240V ac voltage source and absorbs 1200W of active power and 1000VAR of...
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    Engineering Calculating the armature current of the motor.

    Homework Statement A single-phase, full-wave controlled bridge rectifier supplies a permanent magnet dc motor. The rectifier is connected to a 240V ac voltage source and absorbs 1200W of active power and 1000VAR of reactive power from the source. If power loss in the rectifier is negligible...
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    Finding the Surface Area of a Heat Sink: A Homework Guide

    I wasn't given any other figures, I have managed to solve it this way, please correct me if I am wrong: Q is the power dissipated by the device = 25W TJ is the junction temperature in the device = 85˚C TC is the temperature at its case=? TH is the temperature where the heat sink is...
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    Finding the Surface Area of a Heat Sink: A Homework Guide

    Hello I've been stuck with this for ever, can't find the relevant formulas Homework Statement Given that the surface area of the first heat sink, S1= 500 cm2 = 0.05 m2 2nd heat sink = ? The thermal resistance between p-n junction and case, RTjb = 0.6˚C/W The thermal resistance...