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Diffstat (limited to '3731/CH6/EX6.14/Ex6_14.sce')
| -rw-r--r-- | 3731/CH6/EX6.14/Ex6_14.sce | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/3731/CH6/EX6.14/Ex6_14.sce b/3731/CH6/EX6.14/Ex6_14.sce new file mode 100644 index 000000000..292b73078 --- /dev/null +++ b/3731/CH6/EX6.14/Ex6_14.sce @@ -0,0 +1,16 @@ +//Chapter 6:Induction Motor Drives +//Example 14 +clc; + +mprintf("When operating at a frequency K times rated frequency f then") +mprintf("\nIm**2=[((Rr_/Ksf)**2+(2*pi*Lr_)**2)/((Rr_/Ksf)**2+(2*pi*Lm+2*Pi*Lr_)**2)]*Is**2----(1)") +mprintf("\nSince Im is constant for constant flux,") +mprintf("\nK*s*f=constant--------(2)") +mprintf("\nK*Wms*s=constant-------(3) which is the slip speed") +mprintf("\ns*K=constant----------(4)") +mprintf("\nThereofre for a frequency K*f") +mprintf("\nT=(3/K/Wms)*[(Is*K*Xm)**2*(Rr_/s)/((Rr_/s)**2+K**2*(Xm+Xr_)**2]") +mprintf("\nT=(3/K/Wms*s)*[(Is*Xm)**2*(Rr_)/((Rr_/s/K)**2+(Xm+Xr_)**2]-------(5)") +mprintf("\nHence for a given slip speed (K*Wms*s),K*s is constant and from (1) for a given K*s*f and constant flux") +mprintf("\noperation Is is fixed. Now from (5) T is also fixed. Thus, motor develps a constant torque and draws a") +mprintf("\nconstant current from the inverter at all frequencies for a given slip speed") |