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 second heat sink area from thermal resistance and power loss

    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 second heat sink area from thermal resistance and power loss

    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...
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