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Figure shows the single-strand equivalent circuit diagram of a three-phase asynchronous machine with Squirrel-cage rotor for the fundamental.

single-strand equivalent circuit diagram The following parameters are known: R1 = 0.5 Ω R2` = 0.8 Ω Χ1σ = 2.0Ω Χ2σ`= 3.00ΧΗ = 2000 The reactances specified apply to the machine's nominal frequency fn = 50 Hz. It should be assumed that the windings in the stator and rotor are free of current displacement.Friction is neglected.Magnetic saturation phenomena are also not taken into account The increase in resistance due to heating of the winding is not considered. The canceled rotor sizes have already been converted to the stator. The asynchronous machine is operated at no-load on a power converter. the Fundamental slip is close to zero (s1 ~ 0). The fundamental rms value of the phase voltage is U1 = 400 V, the Fundamental frequency is f₁ = f = 50 Hz. Also includes the output voltage 11th and 13th order harmonics. U₁₁/U₁ = 0.15 and U₁3/U₁ = 0.12. Harmonics with higher ordinal numbers can be neglected. Harmonics of the 5th and 7th order do not occur thanks to an optimized pulse pattern. a) Calculate the fundamental current l₁. b) Calculate the harmonic currents l₁1 and 113. Hint: Please state the effective values of the phase currents for a) and b). c) Calculate the Joule heat losses Pv₁ of the fundamental oscillation in no-load operation. d) Calculate the Joule heat losses Pv₁1 and Pv13 of the 11th and 13th harmonic. e) Calculate the total current heat losses PVCu total when the machine is idling.

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