Question

2. Short Answer (20 points) 1. Please draw the equivalent circuit of a 3-phase asynchronous motor (after winding and frequency conversions), explain the meaning of the resistance in rotor circuit and draw the phasor diagram of the machine. (5 points) Please write down the mathematical model of an asynchronous motor and try to make comparison among the control methods (VVVF, VC & DTC) of asynchronous motor. (5 points) 2. 3. It is known for 3-phase double-layer short-pitch distributed windings that: q-2, yi-5, n,-2. Taking one of three phases as example, please draw the winding distribution diagram and calculate the following parameters: pole distance (unit: slots), slop-pitch angle, short-pitch (10 points) coefficient, distributed coefficient.

Answer 1

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onou metor an Jnd Nr--> Actor Speed Ns-dneh ro n cuu Speed Xi Is 工。 E 2. Rc stalor x,→ ancluetance ot the statin. urn cling Re-Core Joss Componun → power Js-> Supply a Equivalent cuuit e ×2→h.ctor wundung inductan a hetmedL6 sta zu

Stala no load Cwrnent VIs talo back em uing uihe above equatien draw the pheses diagnam at tthe above standsill Ii Ic ep- E2:12-2

Phase. Cuagano at tuli İnad atip has oa ol ndu ed omf at any slip s Ni I, 90°チ。 no I,12