Recent content by alex.daciz

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    Understanding Autotransformers and Dot Convention: A Question on V1 and V2

    Thank you both for your input. I have found a similar example which may be useful at the bottom of page 77: http://nptel.iitm.ac.in/courses/IIT-MADRAS/Electrical_Machines_I/pdfs/1_11.pdf It seems to suggest that the current across L2 is I2-I1. In which case the 2 equations would be: V1 =...
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    Understanding Autotransformers and Dot Convention: A Question on V1 and V2

    Woops! Ok another attempt: V1 = [ jωI1 (L1 + M) ] - [ (I2-I1) (jωL2 + M) ] My thinking here is that L1 has self and mutually inductance emf components that are positive with respect to the dot and direction of I1. While L2 has current I2-I1 across it but itself and mutual inductances are...
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    Understanding Autotransformers and Dot Convention: A Question on V1 and V2

    Thanks for your pointer. So should V1 = jωL1I1 + jωMI2 ? because the current is entering at the dotted end of L1 and therefore the mutual inductance is added to the self inductance of L1?
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    Understanding Autotransformers and Dot Convention: A Question on V1 and V2

    Hello, I have the following question regarding autotransformers and dot convention (please see attached). Can anyone give any guidance? I think I have an answer for part (a) but not completely sure if this is correct as I haven't come across a similar example before, sorry about the lack of...
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    Solving rectangular form simultaneous equations?

    Hi, I have the following 3 simultaneous equations to solve for the currents I1, I2 and I3: I1(0-j5) + I1(5+j5) - I3(5+j5) - 20 = 0 I2(5+j5) + I2(0-j10) + I3(0-j10) - 20 = 0 I1(0-j5) + I3(10+j0) - I2(5+j5) = 0 Does anyone have the link to any online software I could use to solve the...
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    A.C. Voltage waveforms and harmonics?

    Sorry my calculator wasn't in radians! Would that then make the error 3.3%?
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    A.C. Voltage waveforms and harmonics?

    Well spotted, it should be -1.2 but re-calculating V at 20ms it's still 70.5V. How have I calculated the error incorrectly?
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    A.C. Voltage waveforms and harmonics?

    Hi, I have the following question: An A.C. voltage, V comprises of a fundamental voltage of 100V rms at a frequency of 120Hz, a 3rd harmonic which is 20% of the fundamental, a 5th harmonic which is 10% of the fundamental and at a phase angle of 1.2 radians lagging. (1) Write down an...
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    Linear and angular acceleration, flywheel

    Homework Statement Hi, I have the following question and was wondering if anyone could help: A mass of 0.5kg is suspended from a flywheel, of mass 3kg, outside radius 0.3m and radius of gyration 0.212m. If the mass is release from rest and falls a distance of 0.5m in 1.5 seconds...
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