Project 1
Problem Statement:
Simulation of starting behaviour of a 5 horsepower(3.75kW), 3-phase 3-wire, 230V, 60Hz, 4-pole squirrel cage induction machine with parameters:
rs=0.531Ω, Lls=Llr=2.52mH
rf=0.408Ω Lm=84.7mHLm=84.7mH
J=0.1kgm2
Procedure:
Below is simulink model designed based on given parameter
Fig.1
Fig.2
Fig.3
- Start up behaviour of induction motor represented in stationary d-q frame where w=0
In that case rotor speed reaches approx. 375 rad/s on appying load speed decreases by some value and after removal of load it again increases.
Fig.4
Fig.5
Fig.6
Fig.7
2. Start up behaviour of induction motor represented in synchronous reference frame where w=wsyn (wsyn = 120f/p= (120*60)/4 = 1800 rpm = ((2*3.14)/60)*1800 = 188.4 rad/s
In that case rotor speed reaches approx. 575 rad/s on appying load speed decreases by some value and after removal of load it again increases.
Fig.8
Fig.9
Fig.10
Fig.11
3. Start up behaviour of induction motor represented in rotor reference frame where w=wr. In that case rotor speed contineously increasing over the period of time and on appying load speed decreases by some value and after removal of load it again increases contineously.
Fig.12
Fig.13
Fig.14
Fig.15
4. Start up behaviour of induction motor represented in rotor flux reference frame where wslip is calculated and based on it wr is recalculated.
In that case reference speed was nearly zero and slip is contineously decreasing in negative direction please see fig 20.
Fig.16
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Fig.18
Fig.19
Fig.20