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diff --git a/1092/CH9/EX9.1/Example9_1.sce b/1092/CH9/EX9.1/Example9_1.sce
new file mode 100755
index 000000000..87435c925
--- /dev/null
+++ b/1092/CH9/EX9.1/Example9_1.sce
@@ -0,0 +1,34 @@
+// Electric Machinery and Transformers

+// Irving L kosow 

+// Prentice Hall of India

+// 2nd editiom

+

+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS

+// Example 9-1

+

+clear; clc; close; // Clear the work space and console.

+

+// Given data

+phase = 3 ; // Number of phases

+n = 3 ; // Slots per pole per phase

+f = 60 ; // Line frequency in Hz

+

+// Calculations

+// case a

+P = 2 * n ; // Number of poles produced

+Total_slots = n * P * phase ; // Total number of slots on the stator

+

+// case b

+S_b = (120*f)/P ; // Speed in rpm of the rotating magnetic field

+

+// case c

+f_c = 50 ; // Changed line frequency in Hz

+S_c = (120*f_c)/P ; // Speed in rpm of the rotating magnetic field

+

+// Display the results

+disp("Example 9-1 Solution : ");

+printf(" \n a: P = %d poles \n    Total slots = %d slots \n", P ,Total_slots );

+

+printf(" \n b: S = %d rpm  @ f = %d Hz \n ", S_b , f );

+

+printf(" \n c: S = %d rpm  @ f = %d Hz ", S_c ,f_c );

diff --git a/1092/CH9/EX9.10/Example9_10.sce b/1092/CH9/EX9.10/Example9_10.sce
new file mode 100755
index 000000000..6a5e01bd5
--- /dev/null
+++ b/1092/CH9/EX9.10/Example9_10.sce
@@ -0,0 +1,64 @@
+// Electric Machinery and Transformers

+// Irving L kosow 

+// Prentice Hall of India

+// 2nd editiom

+

+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS

+// Example 9-10

+

+clear; clc; close; // Clear the work space and console.

+

+// Given data

+P = 4 ; // Number of poles in WRIM

+f = 60 ; // Frequency in Hz

+V = 220 ; // Line voltage in volt

+V_p = 220 ; // Phase voltage in volt (delta connection)

+hp_WRIM = 1 ; // Power rating of WRIM in hp

+S_r = 1740 ; // Full-load rated speed in rpm 

+R_r = 0.3 ; // rotor resistance per phase in ohm/phase 

+R_x = 0.7 ; // Added resistance in ohm/phase 

+X_lr =1 ; // Locked rotor reactance in ohm

+

+// Calculations

+S = (120*f)/P ; // Speed in rpm of the rotating magnetic field

+// case a

+E_lr = V_p / 4 ; // Locked-rotor voltage per phase

+

+// case b

+s = ( S - S_r)/S ; // slip

+I_r = E_lr / sqrt( (R_r/s)^2 + (X_lr)^2 ); // Rotor current per phase at rated speed

+

+// case c

+P_in = ((I_r)^2 * R_r)/s ; // Rated rotor power input per phase

+

+// case d

+P_RL = (I_r)^2 * R_r ; // Rated copper loss per phase

+

+// case e

+P_d_W = P_in - P_RL ; // Rotor power developed per phase in W

+P_d_hp = P_d_W/746 ; // Rotor power developed per phase in hp

+

+// case f

+hp = P_d_hp ; // Rotor power developed per phase in hp

+T_d1 = (hp*5252)/S_r ; // Rotor torque developed in lb-ft per phase by method 1

+T_d2 = 7.04*(P_in/S) ; // Rotor torque developed in lb-ft per phase by method 2

+

+T_dm = 3*T_d1 ; // Total rotor torque in lb-ft

+

+// Display the results

+disp("Example 9-10 Solution : ");

+printf(" \n a: Locked-rotor voltage per phase : \n    E_lr = %d V \n ",E_lr);

+

+printf(" \n b: slip : \n    s = %.2f \n",s);

+printf(" \n    Rotor current per phase at rated speed:\n    I_r = %.3f A/phase \n ",I_r);

+

+printf(" \n c: Rated rotor power input per phase :\n    P_in = %d W/phase \n ",P_in);

+

+printf(" \n d: Rated copper loss per phase : \n    P_RL = %.2f W \n ",P_RL);

+

+printf(" \n e: Rotor power developed per phase in W :\n    P_d = %.1f W/phase ",P_d_W);

+printf(" \n\n    Rotor power developed per phase in hp :\n    P_d = %.2f hp/phase \n ",P_d_hp);

+

+printf(" \n f: Rotor torque developed in lb-ft per phase :\n    T_d = %.1f lb-ft  (method 1)",T_d1);

+printf(" \n\n    T_d = %.1f lb-ft  (method 2)",T_d2);

+printf(" \n\n    Total rotor torque : \n    T_dm = %.1f lb-ft )\n ",T_dm);

diff --git a/1092/CH9/EX9.11/Example9_11.sce b/1092/CH9/EX9.11/Example9_11.sce
new file mode 100755
index 000000000..0cf623d34
--- /dev/null
+++ b/1092/CH9/EX9.11/Example9_11.sce
@@ -0,0 +1,81 @@
+// Electric Machinery and Transformers

+// Irving L kosow 

+// Prentice Hall of India

+// 2nd editiom

+

+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS

+// Example 9-11

+

+clear; clc; close; // Clear the work space and console.

+

+// Given data

+// 3-phase WRIM

+V_L = 208 ; // Voltage rating of the WRIM in volt

+P = 6 ; // Number of poles in WRIM

+f = 60 ; // Frequency in Hz

+P_o = 7.5 ; // Power rating of WRIM in hp

+S_r = 1125 ; // Full-load rotor speed in rpm

+R_r = 0.08 ; // Rotor resistance in ohm/phase 

+X_lr = 0.4 ; // Locked rotor resistance in ohm/phase

+

+// Calculations

+S = (120*f)/P ; // Speed in rpm of the rotating magnetic field

+// case a

+E_lr = (V_L / sqrt(3))/2 ; // Locked rotor voltage per phase

+

+// case b

+s = (S - S_r)/S ; // Full-load rated slip

+I_r = E_lr / sqrt( (R_r/s)^2 + (X_lr)^2 ); // Rotor current in A per phase at rated speed

+

+// case c

+P_in = ( (I_r)^2 * R_r )/s ; // Rated rotor power input per phase in (W/phase)

+

+// case d

+P_RL = ( (I_r)^2 * R_r ); // Rated rotor copper loss per phase (in W/phase)

+

+// case e

+// Subscript W in P_d indicates calculating P_d in W

+P_d_W = P_in - P_RL ; // Rotor power developed per phase (in W/phase)

+// Subscript hp in P_d indicates calculating P_d in hp

+P_d_hp = P_d_W/746 ; // Rotor power developed per phase (in hp/phase)

+

+// case f

+// subscript 1 in T_d indicates method 1 for calculating T_d

+hp = P_d_hp ;

+T_d1 = (hp*5252)/S_r ; // Rotor torque developed per phase in lb-ft

+

+// subscript 2 in T_d indicates method 2 for calculating T_d

+T_d2 = 7.04*(P_in/S); // Rotor torque developed per phase in lb-ft

+

+// case g

+T_dm = 3*T_d1 ; // Total rotor torque in lb-ft

+

+// case h

+T_o = 7.04*(P_o*746)/S_r ; // Total output rotor torque in lb-ft

+

+// Display the results

+disp("Example 9-11 Solution : ");

+

+printf(" \n    Note: Slight variations in the answers I_r,P_in,P_RL,P_d,T_d ");

+printf(" \n          are because of non-approximation of E_lr and (R_r/s)^2 + (X_lr)^2");

+printf(" \n          while calulating in scilab.\n");

+

+printf(" \n a: Locked rotor voltage per phase :\n    E_lr = %d V\n",E_lr);

+

+printf(" \n b: slip :\n    s = %.4f ",s);

+printf(" \n\n    Rotor current per phase at rated speed :\n    I_r = %.2f A/phase\n",I_r);

+

+printf(" \n c: Rated rotor power input per phase :\n    P_in = %.f W/phase\n",P_in);

+

+printf(" \n d: Rated rotor copper loss per phase :\n    P_RL = %.1f W/phase\n",P_RL);

+

+printf(" \n e: Rotor power developed per phase ");

+printf(" \n    P_d = %.f W/phase \n    P_d = %.2f hp/phase\n",P_d_W,P_d_hp);

+

+printf(" \n f: Rotor torque developed per phase : ");

+printf(" \n    (method 1)\n    T_d = %.1f lb-ft/phase",T_d1);

+printf(" \n\n    (method 2)\n    T_d = %.1f lb-ft/phase\n",T_d2);

+

+printf(" \n g: Total rotor torque : \n    T_dm = %d lb-ft\n",T_dm);

+

+printf(" \n h: Total output rotor torque : \n    T_o = %d lb-ft",T_o);

diff --git a/1092/CH9/EX9.12/Example9_12.sce b/1092/CH9/EX9.12/Example9_12.sce
new file mode 100755
index 000000000..34e176054
--- /dev/null
+++ b/1092/CH9/EX9.12/Example9_12.sce
@@ -0,0 +1,47 @@
+// Electric Machinery and Transformers
+// Irving L kosow 
+// Prentice Hall of India
+// 2nd editiom
+
+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS
+// Example 9-12
+
+clear; clc; close; // Clear the work space and console.
+
+// Given data as per Ex.9-10
+P = 4 ; // Number of poles in WRIM
+f = 60 ; // Frequency in Hz
+V = 220 ; // Line voltage in volt
+V_p = 220 ; // Phase voltage in volt (delta connection)
+hp_WRIM = 1 ; // Power rating of WRIM in hp
+S_r = 1740 ; // Full-load rated speed in rpm 
+R_r = 0.3 ; // rotor resistance per phase in ohm/phase 
+R_x = 0.7 ; // Added resistance in ohm/phase 
+X_lr = 1 ; // Locked rotor reactance in ohm
+
+// Calculations from Ex.9-10
+E_lr = V_p / 4 ; // Locked-rotor voltage per phase
+S = (120*f)/P ; // Speed in rpm of the rotating magnetic field
+
+// Calculations (Ex.9-12)
+P_in = (E_lr)^2 / (2*X_lr); // rotor power input(RPI) in W/phase
+P_in_total = P_in * 3 ; // Total 3-phase rotor power input(RPI) in W
+
+T_max = 7.04*(P_in_total/S); // Maximum torque developed in lb-ft
+
+s_b = R_r / X_lr ; // Slip
+
+s = s_b;
+S_r = S*(1 - s); // Rotor speed in rpm for T_max
+
+// Display the results
+disp("Example 9-12 Solution : ");
+
+printf(" \n Rotor power input (RPI) per phase is : ");
+printf(" \n P_in = %.1f W/phase \n",P_in);
+
+printf(" \n The total 3-phase rotor power input (RPI) is : ");
+printf(" \n P_in = %.1f W\n",P_in_total);
+
+printf(" \n Substituting in Eq.(9-19),\n T_max = %.2f lb-ft\n",T_max);
+printf(" \n Then, s_b = %.1f \n and S_r = %d rpm",s_b,S_r);
diff --git a/1092/CH9/EX9.13/Example9_13.sce b/1092/CH9/EX9.13/Example9_13.sce
new file mode 100755
index 000000000..063a6bf6b
--- /dev/null
+++ b/1092/CH9/EX9.13/Example9_13.sce
@@ -0,0 +1,35 @@
+// Electric Machinery and Transformers
+// Irving L kosow 
+// Prentice Hall of India
+// 2nd editiom
+
+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS
+// Example 9-13
+
+clear; clc; close; // Clear the work space and console.
+
+// Given data as per Ex.9-10
+P = 4 ; // Number of poles in WRIM
+f = 60 ; // Frequency in Hz
+V = 220 ; // Line voltage in volt
+V_p = 220 ; // Phase voltage in volt (delta connection)
+hp_WRIM = 1 ; // Power rating of WRIM in hp
+S_r = 1740 ; // Full-load rated speed in rpm 
+R_r = 0.3 ; // rotor resistance per phase in ohm/phase 
+R_x = 0.7 ; // Added resistance in ohm/phase 
+X_lr = 1 ; // Locked rotor reactance in ohm
+
+// Calculations
+E_lr = V_p / 4 ; // Locked-rotor voltage per phase
+S = (120*f)/P ; // Speed in rpm of the rotating magnetic field
+
+// Total 3-phase rotor power input(RPI) in W
+P_in = 3 * ( (E_lr)^2 ) / ( (R_r)^2 + (X_lr)^2 ) * R_r ;
+
+T_s = 7.04 * (P_in/S); // Starting torque developed in lb-ft
+
+// Display the results
+disp("Example 9-13 Solution : ");
+
+printf(" \n P_in = %.f W \n",P_in);
+printf(" \n From Eq.(9-19),starting torque is : \n T_s = %.2f lb-ft",T_s);
diff --git a/1092/CH9/EX9.14/Example9_14.sce b/1092/CH9/EX9.14/Example9_14.sce
new file mode 100755
index 000000000..e1715c743
--- /dev/null
+++ b/1092/CH9/EX9.14/Example9_14.sce
@@ -0,0 +1,29 @@
+// Electric Machinery and Transformers
+// Irving L kosow 
+// Prentice Hall of India
+// 2nd editiom
+
+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS
+// Example 9-14
+
+clear; clc; close; // Clear the work space and console.
+
+// Given data
+T_max = 17.75 ; // Maximum torque developed in lb-ft
+s_max = 0.3 ; // Slip for which T_max occurs
+s_a = 0.0333 ; // slip (case a)
+s_b = 1.0 ; // slip (case b) 
+
+// Calculations
+// Subscript a in T indicates case a
+T_a = T_max * ( 2 / ((s_max/s_a) + (s_a/s_max)) ); // Full-load torque in lb-ft
+
+// Subscript b in T indicates case b
+T_b = T_max * ( 2 / ((s_max/s_b) + (s_b/s_max)) ); // Starting torque in lb-ft
+
+// Display the results
+disp("Example 9-14 Solution : ");
+
+printf(" \n a: Full-load torque at slip = %.4f \n    T = %.1f lb-ft\n",s_a,T_a);
+
+printf(" \n b: Starting torque at slip = %.1f \n    T = %.2f lb-ft\n",s_b,T_b);
diff --git a/1092/CH9/EX9.15/Example9_15.sce b/1092/CH9/EX9.15/Example9_15.sce
new file mode 100755
index 000000000..22d24921c
--- /dev/null
+++ b/1092/CH9/EX9.15/Example9_15.sce
@@ -0,0 +1,143 @@
+// Electric Machinery and Transformers
+// Irving L kosow 
+// Prentice Hall of India
+// 2nd editiom
+
+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS
+// Example 9-15
+
+clear; clc; close; // Clear the work space and console.
+
+// Given data
+// 3-phase Y-connected SCIM
+P = 4 ; // Number of poles in SCIM 
+S_r = 1746 ; // Rated rotor speed in rpm
+V = 220 ; // Voltage rating of SCIM in volt
+f = 60 ; // Frequency in Hz
+P_hp = 10 ; // power rating of SCIM in hp
+R_a = 0.4 ; // Armature resistance in ohm
+R_r = 0.14 ; // Rotor resistance in ohm
+jXm = 16 ; // Reactance in ohm
+jXs = 0.35 ; // Synchronous reactance in ohm
+jXlr = 0.35 ; // Locked rotor reactance in ohm
+P_r_total = 360 ; // Total rotational losses in W
+
+// Calculations
+V_p = V / sqrt(3); // Voltage per phase in volt
+
+S = (120*f)/P ; // Speed in rpm of the rotating magnetic field
+// preliminary calculations
+s = ( S - S_r)/S ; // slip
+
+disp("Example 9-15 :");
+
+printf(" \n From Fig.9-13,using the format method of mesh analysis,we may");
+printf(" \n write the array by inspection :\n");
+printf(" \n __________________________________________________________");
+printf(" \n    I_1(A) \t\t I_2(A) \t\t V(volt)");
+printf(" \n __________________________________________________________");
+printf(" \n   (0.4 + j16.35) \t -(0 + j16) \t\t (127 + j0)");
+printf(" \n   -(0 + j16) \t\t (4.67 + j16.35) \t     0");
+printf(" \n __________________________________________________________");
+
+A = [ (0.4 + %i*16.35) -%i*16 ; (-%i*16)  (4.67 + %i*16.35) ]; // Matrix containing above mesh eqns array
+delta = det(A); // Determinant of A
+
+// case a : Stator armature current I_p in A
+I_p = det( [ (127+%i*0) (-%i*16) ; 0 (4.67 + %i*16.35) ] ) / delta ;
+I_p_m = abs(I_p);//I_p_m=magnitude of I_p in A
+I_p_a = atan(imag(I_p) /real(I_p))*180/%pi;//I_p_a=phase angle of I_p in degrees
+I_1 = I_p ; // Stator armature current in A
+
+// case b : Rotor current I_r per phase in A
+I_r = det( [ (0.4 + %i*16.35) (127+%i*0) ; (-%i*16) 0 ] ) / delta ;
+I_r_m = abs(I_r);//I_r_m=magnitude of I_r in A
+I_r_a = atan(imag(I_r) /real(I_r))*180/%pi;//I_r_a=phase angle of I_r in degrees
+
+// case c
+theta_1 = I_p_a ; // Motor PF angle in degrees
+cos_theta1 = cosd(theta_1); // Motor PF
+
+// case d
+I_p = I_p_m ; // Stator armature current in A
+SPI = V_p * I_p * cos_theta1 ; // Stator Power Input in W
+
+// case e
+SCL = (I_p)^2 * R_a ; // Stator Copper Loss in W
+
+// case f
+// Subscripts 1 and 2 for RPI indicates two methods of calculating RPI
+RPI_1 = SPI - SCL ; // Rotor Power Input in W
+RPI_2 = (I_r_m)^2 * (R_r/s); // Rotor Power Input in W
+RPI =RPI_1 ;
+
+// case g
+// Subscripts 1 , 2 and 3 for RPD indicates three methods of calculating RPD
+RPD_1 = RPI * ( 1 - s ); // Rotor Power Developed in W
+RCL = s*(RPI); // Rotor copper losses in W
+RPD_2 = RPI - RCL ; // Rotor Power Developed in W
+RPD_3 = (I_r_m)^2 * R_r * ((1-s)/s); // Rotor Power Developed in W
+RPD = RPD_1 ;
+
+// case h
+P_r = P_r_total / 3 ; // Rotational Losses per phase in W
+P_o = RPD - P_r ; // Rotor power per phase in W
+P_to = 3*P_o ; // Total rotor power in W
+
+// case i
+T = 7.04 * (P_to/S_r); // Total 3-phase torque in lb-ft
+
+// case j
+P_t = P_to ;
+hp = P_t / 746 ; // Output horsepower
+
+// case k
+P_in = SPI ; // Input power to stator in W
+eta = P_o / P_in * 100 ; // Motor efficiency at rated load
+
+// Display the results
+disp("Solution : ");
+printf(" \n Preliminary calculations\n");
+printf(" \n Slip : s = %.2f \n R_r/s = %.2f ohm \n",s,R_r/s);
+
+printf(" \n Determinant Δ = ");disp(delta);
+
+printf(" \n a: Stator armature current :\n    I_p in A = ");disp(I_1);
+printf(" \n    I_p = I_1 = %.2f <%.2f A \n ",I_p_m , I_p_a );
+
+printf(" \n b: Rotor current per phase :\n    I_r in A = ");disp(I_r);
+printf(" \n    I_r = I_2 = %.3f <%.2f A \n ",I_r_m , I_r_a );
+
+printf(" \n c: Motor PF :\n    cosӨ1 = %.4f \n",cos_theta1);
+
+printf(" \n d: Stator Power Input :\n    SPI = %d W \n",SPI);
+
+printf(" \n e: Stator Copper Loss :\n    SCL = %.f W \n",SCL);
+
+printf(" \n f: Rotor Power Input :\n    RPI = %d W(method 1) ", RPI_1);
+printf(" \n    RPI = %.f W (method 2)\n",RPI_2);
+printf(" \n    Note: RPI calculated by 2nd method slightly varies from that of");
+printf(" \n          textbook value because of non-approximation of I_r while");
+printf(" \n          calculating in scilab.\n")
+
+printf(" \n g: Rotor Power Developed :\n    RPD = %.f W \n",RPD_1);
+printf(" \n    Rotor copper loss :\n    RCL = %d W\n",RCL);
+printf(" \n    RPD = %.f W \n    RPD = %d W \n ",RPD_2,RPD_3);
+
+printf(" \n h: Rotor power per phase :\n    P_o/φ = %f W/φ ",P_o);
+printf(" \n\n    Total rotor power:\n    P_to = %f W \n",P_to);
+printf(" \n    Above P_o/φ and P_to values are not approximated while calculating in ");
+printf(" \n    SCILAB.So,they vary slightly from textbook values.\n");
+
+printf(" \n i: Total 3-phase output torque :\n    T = %.f lb-ft\n",T);
+
+printf(" \n j: Output horsepower : \n    hp = %.1f hp \n",hp);
+
+printf(" \n k: Motor efficiency at rated load :\n    η = %.1f percent \n",eta)
+
+printf(" \n Power flow diagram (per phase)\n");
+printf(" \n   SPI----------> RPI---------> RPD----------> P_o");
+printf(" \n (%d W)   |  (%d W)  |   (%d W)   |   (%d W)",SPI,RPI_1,RPD_3,P_o);
+printf(" \n            |            |              |");
+printf(" \n           SCL          RCL            P_r");
+printf(" \n         (%.f W)       (%d W)         (%d W)",SCL,RCL,P_r);
diff --git a/1092/CH9/EX9.16/Example9_16.sce b/1092/CH9/EX9.16/Example9_16.sce
new file mode 100755
index 000000000..ddd6436ec
--- /dev/null
+++ b/1092/CH9/EX9.16/Example9_16.sce
@@ -0,0 +1,52 @@
+// Electric Machinery and Transformers
+// Irving L kosow 
+// Prentice Hall of India
+// 2nd editiom
+
+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS
+// Example 9-16
+
+clear; clc; close; // Clear the work space and console.
+
+// Given data
+// three-phase SCIM
+V = 208 ; // Rated voltage in volt
+P_o = 15 ; // Rated power in hp
+I = 42 ; // Rated current in A
+I_st = 252 ; // Starting current in A
+T_st = 120 ; // Full-voltage starting torque in lb-ft
+tap = 60*(1/100) ; // Tapping in % employed by compensator
+
+// Calculations
+// case a
+I_sm = tap * I_st ; // Motor starting current in A at reduced voltage 
+
+// case b
+I_L = tap * I_sm ; // Motor line current in A(neglecting tarnsformer exciting 
+// current and losses)
+
+// case c
+T_s = (tap)^2 * T_st ; // Motor starting torque at reduced voltage in lb-ft
+
+// case d
+percent_I_L = I_L / I_st * 100 ; // Percent line current at starting
+
+// case e
+percent_T_st = T_s / T_st * 100 ; // Percent motor starting torque
+
+// Display the results
+disp("Example 9-16 Solution : ");
+
+printf(" \n a: Motor starting current at reduced voltage : ");
+printf(" \n    I_sm = %.1f A to the motor.\n",I_sm);
+
+printf(" \n b: Motor line current neglecting tarnsformer exciting current and losses :");
+printf(" \n    I_L = %.2f A drawn from the mains.\n",I_L);
+
+printf(" \n c: Motor starting torque at reduced voltage :\n    T_s = %.1f lb-ft\n",T_s);
+
+printf(" \n d: Percent line current at starting : ");
+printf(" \n    = %.f percent of line current at full voltage.\n",percent_I_L);
+
+printf(" \n e: Percent motor starting torque : ");
+printf(" \n    = %d percent of starting torque at full voltage.\n",percent_T_st);
diff --git a/1092/CH9/EX9.17/Example9_17.sce b/1092/CH9/EX9.17/Example9_17.sce
new file mode 100755
index 000000000..d0fb0539f
--- /dev/null
+++ b/1092/CH9/EX9.17/Example9_17.sce
@@ -0,0 +1,77 @@
+// Electric Machinery and Transformers
+// Irving L kosow 
+// Prentice Hall of India
+// 2nd editiom
+
+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS
+// Example 9-17
+
+clear; clc; close; // Clear the work space and console.
+
+// Given data
+// three-phase SCIM
+V_o = 220 ; // Rated voltage in volt
+P = 4 ; // Number of poles in SCIM
+P_o = 10 ; // Rated power in hp
+f = 60 ; // Frequency in Hz(assume,not given)
+T_o = 30 ; // Rated torque in lb-ft
+S_r = 1710 ; // Rated rotor speed in rpm
+V_n1 = 242 ; // Impressed stator voltage in volt(case a)
+V_n2 = 198 ; // Impressed stator voltage in volt(case b)
+
+// Calculations
+S = (120*f)/P ; // Speed in rpm of the rotating magnetic field
+// case a : Impressed stator voltage = 242 V
+s_o = (S - S_r)/S ; // Rated slip
+
+T_n1 = T_o * (V_n1/V_o)^2 ; // New torque in lb-ft
+
+s_n1 = s_o * (T_o/T_n1); // New slip
+
+S_rn1 = S*(1 - s_n1); 
+
+// case b : Impressed stator voltage = 198 V
+T_n2 = T_o * (V_n2/V_o)^2 ; // New torque in lb-ft
+
+s_n2 = s_o * (T_o/T_n2); // New slip
+
+S_rn2 = S*(1 - s_n2);
+
+// case c
+// Subscript a in percent_slip and percent_speed indicates part a
+percent_slip_a = (s_o - s_n1)/s_o * 100 ; // Percent change in slip in part(a)
+
+percent_speed_a = (S_rn1 - S_r)/S_r * 100; // Percent change in speed in part(a)
+
+// case d
+// Subscript b in percent_slip and percent_speed indicates part b
+percent_slip_b = (s_n2 - s_o)/s_o * 100 ; // Percent change in slip in part(b)
+
+percent_speed_b = (S_r - S_rn2)/S_r * 100; // Percent change in speed in part(b)
+
+// Display the results
+disp("Example 9-17 Solution : ");
+
+printf(" \n a: Rated slip :\n    s = %.2f\n",s_o);
+printf(" \n    For impressed stator voltage = %d V \n ",V_n1);
+printf(" \n    New torque :\n    T_n = %.1f lb-ft \n ",T_n1);
+printf(" \n    New slip :\n    s_n = %f \n ",s_n1);
+printf(" \n    New rotor speed :\n    S_r = %f rpm \n",S_rn1);
+
+printf(" \n b: For impressed stator voltage = %d V \n ",V_n2);
+printf(" \n    New torque :\n    T_n = %.1f lb-ft \n ",T_n2);
+printf(" \n    New slip :\n    s_n = %f \n ",s_n2);
+printf(" \n    New rotor speed :\n    S_r = %f rpm \n",S_rn2);
+
+printf(" \n c: Percent change in slip in part(a)");
+printf(" \n    = %.1f percent decrease.\n",percent_slip_a);
+printf(" \n    Percent change in speed in part(a)");
+printf(" \n    = %.2f percent increase \n",percent_speed_a);
+
+printf(" \n d: Percent change in slip in part(b)");
+printf(" \n    = %.2f percent increase.\n",percent_slip_b);
+printf(" \n    Percent change in speed in part(b)");
+printf(" \n    = %.2f percent decrease\n",percent_speed_b);
+
+printf(" \n   SLIGHT VARIATIONS IN PERCENT CHANGE IN SLIP AND SPEED ARE DUE TO");
+printf(" \n   NON-APPROXIMATION OF NEW SLIPS AND NEW SPEEDS CALCULATED IN SCILAB.")
diff --git a/1092/CH9/EX9.18/Example9_18.sce b/1092/CH9/EX9.18/Example9_18.sce
new file mode 100755
index 000000000..8a77f567b
--- /dev/null
+++ b/1092/CH9/EX9.18/Example9_18.sce
@@ -0,0 +1,70 @@
+// Electric Machinery and Transformers
+// Irving L kosow 
+// Prentice Hall of India
+// 2nd editiom
+
+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS
+// Example 9-18
+
+clear; clc; close; // Clear the work space and console.
+
+// Given data
+// three-phase WRIM
+V_o = 220 ; // Rated voltage in volt
+P_o = 10 ; // Rated power in hp
+P = 4 ; // Number of poles in WRIM(assumption)
+f = 60 ; // Frequency in Hz(assume,not given)
+R_ro = 0.3 ; // Rotor resistance in ohm
+T_o = 30 ; // Rated torque in lb-ft
+S_r = 1750 ; // Rated rotor speed in rpm
+R_r_ext = 1.7 ; // External rotor resistance in ohm/phase inserted in the rotor ckt 
+R_rn = R_ro + R_r_ext ; // Total rotor resistance in ohm
+
+V_n1 = 240 ; // Impressed stator voltage in volt(case a)
+V_n2 = 208 ; // Impressed stator voltage in volt(case b)
+V_n3 = 110 ; // Impressed stator voltage in volt(case c)
+
+// Calculations
+S = (120*f)/P ; // Speed in rpm of the rotating magnetic field
+
+// case a : Impressed stator voltage = 240 V
+s_o = (S - S_r)/S ; // Rated slip
+
+T_n1 = T_o * (V_n1/V_o)^2 ; // New torque in lb-ft
+
+s_n1 = s_o * (T_o/T_n1) * (R_rn/R_ro); // New slip
+
+S_rn1 = S*(1 - s_n1); 
+
+// case b : Impressed stator voltage = 208 V
+T_n2 = T_o * (V_n2/V_o)^2 ; // New torque in lb-ft
+
+s_n2 = s_o * (T_o/T_n2) * (R_rn/R_ro); // New slip
+
+S_rn2 = S*(1 - s_n2);
+
+// case c : Impressed stator voltage = 110 V
+T_n3 = T_o * (V_n3/V_o)^2 ; // New torque in lb-ft
+
+s_n3 = s_o * (T_o/T_n3) * (R_rn/R_ro); // New slip
+
+S_rn3 = S*(1 - s_n3);
+
+// Display the results
+disp("Example 9-18 Solution : ");
+
+printf(" \n a: Rated slip :\n    s = %f\n",s_o);
+printf(" \n    For impressed stator voltage = %d V \n ",V_n1);
+printf(" \n    New torque :\n    T_n = %.1f lb-ft \n ",T_n1);
+printf(" \n    New slip :\n    s_n = %f \n ",s_n1);
+printf(" \n    New rotor speed :\n    S_r = %f rpm \n",S_rn1);
+
+printf(" \n b: For impressed stator voltage = %d V \n ",V_n2);
+printf(" \n    New torque :\n    T_n = %.2f lb-ft \n ",T_n2);
+printf(" \n    New slip :\n    s_n = %f \n ",s_n2);
+printf(" \n    New rotor speed :\n    S_r = %f rpm \n",S_rn2);
+
+printf(" \n c: For impressed stator voltage = %d V \n ",V_n3);
+printf(" \n    New torque :\n    T_n = %.1f lb-ft \n ",T_n3);
+printf(" \n    New slip :\n    s_n = %f \n ",s_n3);
+printf(" \n    New rotor speed :\n    S_r = %f rpm \n",S_rn3);
diff --git a/1092/CH9/EX9.19/Example9_19.sce b/1092/CH9/EX9.19/Example9_19.sce
new file mode 100755
index 000000000..b6d9bda71
--- /dev/null
+++ b/1092/CH9/EX9.19/Example9_19.sce
@@ -0,0 +1,53 @@
+// Electric Machinery and Transformers
+// Irving L kosow 
+// Prentice Hall of India
+// 2nd editiom
+
+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS
+// Example 9-19
+
+clear; clc; close; // Clear the work space and console.
+
+// Given data
+P = 8 ; // Number of poles in WRIM
+f = 60 ; // Operating frequency of the WRIM in Hz
+/// WRIM is driven by variable-speed prime mover as a frequency changer
+S_con_a1 = 1800 ; // Speed of the convertor in rpm
+S_con_a2 = 450 ; // Speed of the convertor in rpm
+
+f_con_b1 = 25 ; // Frequency of an induction converter in Hz
+f_con_b2 = 400 ; // Frequency of an induction converter in Hz
+f_con_b3 = 120 ; // Frequency of an induction converter in Hz
+
+// Calculations
+S = (120*f)/P ; // Speed in rpm of the rotating magnetic field
+
+// case a
+// Subscript a1 in f_con indicates case a 1st frequecy in Hz
+f_con_a1 = f*(1 + S_con_a1/S); // Frequency of an induction converter in Hz
+
+// Subscript a2 in f_con indicates case a 2nd frequency in Hz
+f_con_a2 = f*(1 - S_con_a2/S); // Frequency of an induction converter in Hz
+
+// case b
+// Subscript b1 in S-con indicates case b 1st speed of converter in rpm
+S_con_b1 = ( -1 + f_con_b1/f) * S ; // Speed of the convertor in rpm
+
+// Subscript b2 in S-con indicates case b 2nd speed of converter in rpm
+S_con_b2 = ( -1 + f_con_b2/f) * S ; // Speed of the convertor in rpm
+
+// Subscript b3 in S-con indicates case b 3rd speed of converter in rpm
+S_con_b3 = ( -1 + f_con_b3/f) * S ; // Speed of the convertor in rpm
+
+
+// Display the results
+disp("Example 9-19 Solution : ");
+
+printf(" \n Using Eq.(9-26),\n");
+
+printf(" \n a: f_con = %d Hz for %d rpm in opposite direction\n",f_con_a1,S_con_a1);
+printf(" \n    f_con = %d Hz for %d rpm in same direction\n",f_con_a2,S_con_a2);
+
+printf(" \n b: 1. S_con = %.f rpm, or %.f rpm in same direction.\n",S_con_b1,abs(S_con_b1));
+printf(" \n    2. S_con = %d rpm in opposite direction.\n",S_con_b2);
+printf(" \n    3. S_con = %d rpm in opposite direction to rotating stator flux.\n",S_con_b3);
diff --git a/1092/CH9/EX9.2/Example9_2.sce b/1092/CH9/EX9.2/Example9_2.sce
new file mode 100755
index 000000000..28f36e6da
--- /dev/null
+++ b/1092/CH9/EX9.2/Example9_2.sce
@@ -0,0 +1,35 @@
+// Electric Machinery and Transformers

+// Irving L kosow 

+// Prentice Hall of India

+// 2nd editiom

+

+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS

+// Example 9-2

+

+clear; clc; close; // Clear the work space and console.

+

+// Given data

+

+s_a = 5*(1/100); // Slip (case a)

+s_b = 7*(1/100); // Slip (case b)

+

+// Given data and calculated values from Ex.9-1

+f_a = 60 ; // Line frequency in Hz (case a)

+f_b = 50 ; // Line frequency in Hz (case b)

+S_a = 1200 ; // Speed in rpm of the rotating magnetic field (case a)

+S_b = 1000 ; // Speed in rpm of the rotating magnetic field (case b)

+

+// Calculations

+

+// case a

+S_r_a = S_a * ( 1 - s_a ); // Rotor speed in rpm when slip is 5% (case a)

+

+// case b

+S_r_b = S_b * ( 1 - s_b ); // Rotor speed in rpm when slip is 7% (case b)

+

+// Display the results

+disp("Example 9-2 Solution : ");

+

+printf(" \n a: S_r = %.f rpm  @ s = %.2f  \n ", S_r_a ,s_a );

+

+printf(" \n b: S_r = %.f rpm  @ s = %.2f  ", S_r_b ,s_b );

diff --git a/1092/CH9/EX9.3/Example9_3.sce b/1092/CH9/EX9.3/Example9_3.sce
new file mode 100755
index 000000000..5a5029e16
--- /dev/null
+++ b/1092/CH9/EX9.3/Example9_3.sce
@@ -0,0 +1,37 @@
+// Electric Machinery and Transformers

+// Irving L kosow 

+// Prentice Hall of India

+// 2nd editiom

+

+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS

+// Example 9-3

+

+clear; clc; close; // Clear the work space and console.

+

+// Given data

+P = 4 ; // Number of poles in Induction motor

+f = 60 ; // Frequency in Hz 

+s_f = 5*(1/100) ; // Full-load rotor slip

+

+// Calculations

+

+// case a

+// slip, s = (S -S_r)/S ; 

+// where S = Speed in rpm of the rotating magnetic field and 

+//       S_r = Speed in rpm of the rotor

+s = 1 ; // Slip = 1, at the instant of starting, since S_r is zero

+f_r_a = s * f ; // Rotor frequency in Hz at the instant of starting

+

+// case b

+f_r_b = s_f * f ;// Full-load rotor frequency in Hz

+

+// Display the results

+disp("Example 9-3 Solution : ");

+

+printf(" \n a: At the instant of starting, slip s = (S -S_r)/S ; ");

+printf(" \n    where S_r is the rotor speed. Since the rotor speed at the ");

+printf(" \n    instant of starting is zero, s = (S - 0)/S = 1 , or unity slip.");

+printf(" \n\n    The rotor frequency is \n    f_r  = %d Hz \n\n ", f_r_a);

+

+printf(" \n b: At full-load,the slip is 5 percent(as given), and therefore");

+printf(" \n    s = %.2f \n    f_r = %d Hz " , s_f , f_r_b);

diff --git a/1092/CH9/EX9.4/Example9_4.sce b/1092/CH9/EX9.4/Example9_4.sce
new file mode 100755
index 000000000..d6b0a3377
--- /dev/null
+++ b/1092/CH9/EX9.4/Example9_4.sce
@@ -0,0 +1,30 @@
+// Electric Machinery and Transformers

+// Irving L kosow 

+// Prentice Hall of India

+// 2nd editiom

+

+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS

+// Example 9-4

+

+clear; clc; close; // Clear the work space and console.

+

+// Given data

+P = 4 ; // Number of poles in the IM

+hp = 50 ; // rating of the IM in hp

+V_o = 208 ; // Voltage rating of the IM in volt

+T_orig = 225 ; // Starting torque in lb-ft

+I_orig = 700 ; // Instantaneous startign current in A at rated voltage

+V_s = 120 ; // Reduced 3-phase voltage supplied in volt

+

+// Calculations

+// case a

+T_s = T_orig * (V_s/V_o)^2 ; // Starting torque in lb-ft after application of V_s

+

+// case b

+I_s = I_orig * (V_s/V_o) ; // Starting current in A after application of V_s

+

+// Display the results

+disp("Example 9-4 Solution : ");

+printf(" \n a: Starting torque :\n    T_s = %.f lb-ft \n",T_s );

+

+printf(" \n b: Starting current :\n    I_s = %d A \n",I_s );

diff --git a/1092/CH9/EX9.5/Example9_5.sce b/1092/CH9/EX9.5/Example9_5.sce
new file mode 100755
index 000000000..bb0e0a36d
--- /dev/null
+++ b/1092/CH9/EX9.5/Example9_5.sce
@@ -0,0 +1,41 @@
+// Electric Machinery and Transformers

+// Irving L kosow 

+// Prentice Hall of India

+// 2nd editiom

+

+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS

+// Example 9-5

+

+clear; clc; close; // Clear the work space and console.

+

+// Given data

+P = 8 ; // Number of poles in the SCIM

+f = 60 ; // Frequency in Hz

+R_r = 0.3 ; // Rotor resistance per phase in ohm

+S_r = 650 ; // Speed in rpm at which motor stalls

+

+// Calculations

+// case a

+S = (120*f)/P ; // Speed in rpm of the rotating magnetic field

+s_b = (S - S_r)/S ; // Breakdown Slip

+

+// case b

+X_lr = R_r / s_b ; // Locked rotor reactance in ohm

+

+// case c

+f_r = s_b * f ; // Rotor frequency in Hz, at the maximum torque point 

+

+// case d

+s = 5*(1/100);//  Rated slip

+S_r = S * (1 - s); // Full-load in rpm speed at rated slip 

+

+// Display the results

+disp("Example 9-5 Solution : ");

+printf(" \n a: S = %d rpm \n    s_b = %.3f \n", S , s_b );

+

+printf(" \n b: X_b = %.2f ohm \n ", X_lr );

+

+printf(" \n c: f_r = %.1f Hz \n ", f_r );

+

+printf(" \n d: S = %d rpm \n ", S_r );

+

diff --git a/1092/CH9/EX9.6/Example9_6.sce b/1092/CH9/EX9.6/Example9_6.sce
new file mode 100755
index 000000000..90d9834c2
--- /dev/null
+++ b/1092/CH9/EX9.6/Example9_6.sce
@@ -0,0 +1,67 @@
+// Electric Machinery and Transformers

+// Irving L kosow 

+// Prentice Hall of India

+// 2nd editiom

+

+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS

+// Example 9-6

+

+clear; clc; close; // Clear the work space and console.

+

+// Given data

+P = 8 ; // Number of poles in the SCIM

+f = 60 ; // Frequency in Hz

+R_r = 0.3 ; // rotor resistance per phase in ohm/phase 

+R_x = 0.7 ; // Added resistance in ohm/phase 

+R_r_total = R_r + R_x ; // Total resistance per phase in ohm

+S_r = 875 ; // Full-load Speed in rpm 

+

+

+// Calculated values from Ex.9-6

+S = 900 ; // Speed in rpm of the rotating magnetic field

+X_lr = 1.08 ; // Locked rotor reactance in ohm

+

+// Calculations

+// case a

+s = (S - S_r)/S ; // Full-load slip,short circuited

+s_r = R_r_total / R_r * s; // New full-load slip with added resistance

+

+S_r_new = S*(1-s_r); // New full-load speed in rpm 

+

+// case b

+// Neglecting constant Kn_t ,since we are taking torque ratios

+T_o = ( R_r / ((R_r)^2 + (X_lr)^2) ); // Original torque

+T_f = ( R_r + R_x) / ( (R_r + R_x)^2  + (X_lr)^2 ); // Original torque

+

+torque_ratio = T_f / T_o ; // Ratio of final torque to original torque

+T_final = 2*torque_ratio ;

+

+// Display the results

+disp("Example 9-6 Solution : ");

+printf(" \n a: The full-load slip,short circuited,is ");

+printf(" \n    s = %.4f \n",s );

+printf(" \n    Since slip is proportional to rotor resistance and since the ");

+printf(" \n    increased rotor resistance is R_r = %.1f + %.1f = %d ,",R_x,R_r,R_r_total);

+printf(" \n    the new full-load slip with added resistance is : ");

+printf(" \n    s_r = %.4f \n",s_r);

+printf(" \n    The new full-load speed is : " );

+printf(" \n    S(1-s) = %.f rpm \n",S_r_new );

+

+printf(" \n b: The original starting torque T_o was twice the full-load torque");

+printf(" \n    with a rotor resistance of %.1f ohm and a rotor reactance of %.2f ohm",R_r,X_lr);

+printf(" \n    (Ex.9-5).The new starting torque conditions may be summarized by the   ");

+printf(" \n    following table and compared from Eq.(9-14),where T_o ");

+printf(" \n    is the original torque and T_f is the new torque.");

+

+printf(" \n    _________________________________________");

+printf(" \n    Condition \t R_r \t X_lr \t T_starting ");

+printf(" \n              \t ohm \t ohm  \t ");

+printf(" \n    _________________________________________");

+printf(" \n    Original : \t %.1f \t %.2f \t 2*T_n ",R_r,X_lr);

+printf(" \n    New      : \t %.1f \t %.2f \t   ?   ",R_r_total,X_lr);

+printf(" \n    _________________________________________\n");

+

+printf(" \n    T_o = %.2f * K_n_t",T_o);

+printf(" \n    T_f = %.3f * K_n_t",T_f);

+printf(" \n    T_f/T_o = %.2f and T_f = %.2f * T_o\n ",torque_ratio,torque_ratio);

+printf(" \n    Therefore,\n    T_f = %.3f * T_n",T_final);

diff --git a/1092/CH9/EX9.7/Example9_7.sce b/1092/CH9/EX9.7/Example9_7.sce
new file mode 100755
index 000000000..af4cfa69f
--- /dev/null
+++ b/1092/CH9/EX9.7/Example9_7.sce
@@ -0,0 +1,54 @@
+// Electric Machinery and Transformers

+// Irving L kosow 

+// Prentice Hall of India

+// 2nd editiom

+

+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS

+// Example 9-7

+

+clear; clc; close; // Clear the work space and console.

+

+// Given data

+P = 8 ; // Number of poles in the SCIM

+f = 60 ; // Frequency in Hz

+R_r = 0.3 ; // Rotor resistance per phase in ohm

+R_x = 0.7 ; // Added resistance in ohm/phase 

+R_r_total = R_r + R_x ; // Total resistance per phase in ohm

+X_lr = 1.08 ; // Locked rotor reactance in ohm

+S_r = 650 ; // Speed in rpm at which motor stalls

+E_lr = 112 ; // Induced voltage per phase

+

+// Calculations

+// case a

+Z_lr = R_r + %i*X_lr ; // Locked rotor impedance per phase

+Z_lr_m = abs(Z_lr);//Z_lr_m = magnitude of Z_lr in ohm

+Z_lr_a = atan(imag(Z_lr) /real(Z_lr))*180/%pi;//Z_lr_a=phase angle of Z_lr in degrees

+

+I_r = E_lr / Z_lr_m ; // Rotor current per phase

+cos_theta_r = cosd(Z_lr_a); // rotor power factor with the rotor short-circuited

+cos_theta = R_r / Z_lr_m ; // rotor power factor with the rotor short-circuited

+

+// case b

+// 1 at the end of Z_lr1 is just used for showing its different form Z_lr 

+// and for ease in calculations

+Z_lr1 = R_r_total + %i*X_lr ; // Locked rotor impedance per phase

+Z_lr1_m = abs(Z_lr1);//Z_lr1_m = magnitude of Z_lr1 in ohm

+Z_lr1_a = atan(imag(Z_lr1) /real(Z_lr1))*180/%pi;//Z_lr1_a=phase angle of Z_lr1 in degrees

+

+I_r1 = E_lr / Z_lr1_m ; // Rotor current per phase

+cos_theta_r1 = cosd(Z_lr1_a); // rotor power factor with the rotor short-circuited

+cos_theta1 = R_r_total / Z_lr1_m ; // rotor power factor with the rotor short-circuited

+

+// Display the results

+disp("Example 9-7 Solution : ");

+printf(" \n a: The locked-rotor impedance per phase is : ");

+printf(" \n    Z_lr in ohm = "),disp(Z_lr);

+printf(" \n    Z_lr = %.2f <%.1f ohm \n",Z_lr_m,Z_lr_a);

+printf(" \n    I_r = %.f A \n",I_r);

+printf(" \n    cosθ_r = cos(%.1f) = %.3f or \n    cosθ = R_r/Z_lr = %.3f",Z_lr_a,cos_theta_r,cos_theta);

+

+printf(" \n\n\n b: The locked-rotor impedance with added rotor resistance per phase is : ");

+printf(" \n    Z_lr in ohm = "),disp(Z_lr1);

+printf(" \n    Z_lr = %.2f <%.1f ohm \n",Z_lr1_m,Z_lr1_a);

+printf(" \n    I_r = %.1f A \n",I_r1);

+printf(" \n    cosθ_r = cos(%.1f) = %.3f or \n    cosθ = R_r/Z_lr = %.3f",Z_lr1_a,cos_theta_r1,cos_theta1);

diff --git a/1092/CH9/EX9.8/Example9_8.sce b/1092/CH9/EX9.8/Example9_8.sce
new file mode 100755
index 000000000..d84dc04d8
--- /dev/null
+++ b/1092/CH9/EX9.8/Example9_8.sce
@@ -0,0 +1,90 @@
+// Electric Machinery and Transformers

+// Irving L kosow 

+// Prentice Hall of India

+// 2nd editiom

+

+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS

+// Example 9-8

+

+clear; clc; close; // Clear the work space and console.

+

+// Given data  (Exs.9-5 through 9-7)

+P = 8 ; // Number of poles in the SCIM

+f = 60 ; // Frequency in Hz

+R_r = 0.3 ; // Rotor resistance per phase in ohm

+X_lr = 1.08 ; // Locked rotor reactance in ohm

+S_r = 650 ; // Speed in rpm at which motor stalls

+E_lr = 112 ; // Induced voltage per phase

+

+disp("Example 9-8 : "); 

+printf(" \n The new and the original conditions may be summarized in the following table\n");

+printf(" \n    _________________________________________________________");

+printf(" \n    Condition \t R_r \t\t X_lr \t\t T_starting ");

+printf(" \n              \t ohm \t\t ohm  \t ");

+printf(" \n    _________________________________________________________");

+printf(" \n    Original : \t %.1f \t\t %.2f \t\t T_o = 2*T_n ",R_r,X_lr);

+printf(" \n    New      :\t(%.1f+R_x) \t %.2f \t\t T_n = 2*T_n ",R_r,X_lr);

+printf(" \n    _________________________________________________________\n");

+

+// Calculating

+// case a

+// Neglecting constant Kn_t ,since we are equating torque T_o and T_n

+T_o = ( R_r / ((R_r)^2 + (X_lr)^2) ); // Original torque

+

+// T_o = K_n_t*( 0.3 / ((0.3)^2 + (1.08)^2) );

+// T_n = K_n_t*( 0.3 + R_x) / ( (0.3 + R_x)^2  + (1.08)^2 );

+// T_n = T_o

+// Simplyifing yields

+// 0.3 + R_x = 0.24[(0.3+R_x)^2 + (1.08)^2]

+// Expanding and combining the terms yields

+// 0.24*(R_x)^2 - 0.856*R_x = 0

+// This is a quadratic equation having two roots,which may be factored as

+// R_x*(0.24*R_x - 0.856) = 0,yielding

+// R_x = 0 and R_x = 0.856/0,24 = 3.57

+R_x = poly(0,'R_x'); // Defining a polynomial with variable 'R_x' with  root at 0

+a = 0.24 ; // coefficient of x^2

+b = -0.856 ; // coefficient of x

+c = 0 ; // constant

+

+// Roots of p

+R_x1 = ( -b + sqrt (b^2 -4*a*c ) ) /(2* a);

+R_x2=( -b - sqrt (b^2 -4*a*c ) ) /(2* a);

+// Consider R_x>0 value, 

+R_x = R_x1;

+

+R_T = R_r + R_x ; // Total rotor resistance in ohm

+

+// case b

+Z_T = R_T + %i*X_lr ; // Total impedance in ohm

+Z_T_m = abs(Z_T);//Z_T_m = magnitude of Z_T in ohm

+Z_T_a = atan(imag(Z_T) /real(Z_T))*180/%pi;//Z_T_a=phase angle of Z_T in degrees

+

+cos_theta = R_T / Z_T_m ; // Rotor PF that will produce the same starting torque

+

+// case c

+Z_r = Z_T_m ; // Impedance in ohm

+I_r = E_lr / Z_r ; // Starting current in A

+

+// Display the results

+disp("Solution : "); 

+

+printf(" \n a: T_o = %.2f * K_n_t ",T_o );

+printf(" \n    T_n = %.2f * K_n_t \n",T_o );

+printf(" \n    Simplyifing yields");

+printf(" \n    0.3 + R_x = 0.24[(0.3+R_x)^2 + (1.08)^2]");

+printf(" \n    Expanding and combining the terms yields");

+printf(" \n    0.24*(R_x)^2 - 0.856*R_x = 0");

+printf(" \n    This is a quadratic equation having two roots,which may be factored as");

+printf(" \n    R_x*(0.24*R_x - 0.856) = 0,yielding");

+printf(" \n    R_x = 0 ohm and R_x = 0.856/0.24 = 3.57 ohm\n\n    This proves that ");

+printf(" \n    Original torque is produced with an external resistance of either ");

+printf(" \n    zero or 12 times the origianl rotor resistance.Therefore,\n");

+printf(" \n    R_T = R_r + R_x = %.2f ohm \n",R_T);

+

+printf(" \n b: Z_T in ohm = ");disp(Z_T);

+printf(" \n    Z_T = %.2f <%.1f ohm ",Z_T_m,Z_T_a);

+printf(" \n    cosӨ = R_T / Z_T = %.3f or \n    cosӨ = cosd(%.1f) = %.3f\n",cos_theta,Z_T_a,cosd(Z_T_a));

+

+printf(" \n c: I_r = E_lr / Z_r = %.f A \n\n    This proves that,",I_r);

+printf(" \n    Rotor current at starting is now only 28 percent of the original");

+printf(" \n    starting current in part(a) of Ex.9-7");

diff --git a/1092/CH9/EX9.9/Example9_9.sce b/1092/CH9/EX9.9/Example9_9.sce
new file mode 100755
index 000000000..647a6926d
--- /dev/null
+++ b/1092/CH9/EX9.9/Example9_9.sce
@@ -0,0 +1,77 @@
+// Electric Machinery and Transformers

+// Irving L kosow 

+// Prentice Hall of India

+// 2nd editiom

+

+// Chapter 9: POLYPHASE INDUCTION (ASYNCHRONOUS) DYNAMOS

+// Example 9-9

+

+clear; clc; close; // Clear the work space and console.

+

+// Given data

+P = 8 ; // Number of poles in the SCIM

+f = 60 ; // Frequency in Hz

+S_r = 875 ; // Full-load Speed in rpm with rotor short-circuited

+R_r = 0.3 ; // rotor resistance per phase in ohm/phase 

+R_x = 0.7 ; // Added resistance in ohm/phase 

+R_x_a = 1.7 ; // Added resistance in ohm/phase (case a)

+R_x_b = 2.7 ; // Added resistance in ohm/phase (case b) 

+R_x_c = 3.7 ; // Added resistance in ohm/phase (case c) 

+R_x_d = 4.7 ; // Added resistance in ohm/phase (case d) 

+

+// Calculations

+S = (120*f)/P ; // Speed in rpm of the rotating magnetic field

+s_o = (S - S_r)/S ; //  Slip at rotor speed 875 rpm

+

+// case a

+s_r_a = s_o * (R_r + R_x_a)/R_r; // Rated slip

+S_r_a = S * (1 - s_r_a); // Full-load speed in rpm for added resistance R_x_a

+

+// case b

+s_r_b = s_o * (R_r + R_x_b)/R_r; // Rated slip

+S_r_b = S * (1 - s_r_b); // Full-load speed in rpm for added resistance R_x_b

+

+// case c

+s_r_c = s_o * (R_r + R_x_c)/R_r; // Rated slip

+S_r_c = S * (1 - s_r_c); // Full-load speed in rpm for added resistance R_x_c

+

+// case d

+s_r_d = s_o * (R_r + R_x_d)/R_r; // Rated slip

+S_r_d = S * (1 - s_r_d); // Full-load speed in rpm for added resistance R_x_d

+

+// Display the results

+disp("Example 9-9 Solution : ");

+

+printf(" \n Slip s_r = s_o*(R_r+R_x)/R_r \n Rotor speed S_r = S_o*(1-s)\n");

+

+printf(" \n    Calculated value of s_o = %f , instead of 0.0278(textbook)",s_o)

+printf(" \n    so slight variations in the answers below.\n");

+

+printf(" \n a: When R_x = %.1f ohm ",R_x_a);

+printf(" \n    s_r = %.3f \n    S_r = %.1f rpm \n",s_r_a,S_r_a );

+

+printf(" \n b: When R_x = %.1f ohm ",R_x_b);

+printf(" \n    s_r = %.3f \n    S_r = %.1f rpm \n",s_r_b,S_r_b );

+

+printf(" \n c: When R_x = %.1f ohm ",R_x_c);

+printf(" \n    s_r = %.3f \n    S_r = %.1f rpm \n",s_r_c,S_r_c );

+

+printf(" \n d: When R_x = %.1f ohm ",R_x_d);

+printf(" \n    s_r = %.3f \n    S_r = %.1f rpm \n",s_r_d,S_r_d );

+

+printf(" \n    This example,verifies that slip is proportional to rotor resistance");

+printf(" \n    as summarized below.");

+

+printf(" \n  ___________________________________________________________________");

+printf(" \n    R_T(ohm) = R_r+R_x \t\t Slip \t\t Full-load Speed(rpm)");

+printf(" \n  ___________________________________________________________________");

+printf(" \n      Given \t\t\t Given \t\t Given \t\ ");

+printf(" \n      0.3 \t\t\t 0.0278 \t 875 ");

+printf(" \n      0.3+0.1 = 1.0 \t\t 0.0926 \t 817");

+printf(" \n  ___________________________________________________________________");

+printf(" \n      Given \t\t\t Calculated \t Calculated \t\ ");

+printf(" \n   a. %.1f + %.1f = %.1f \t\t %.3f \t\t %.1f ",R_r,R_x_a,R_r+R_x_a,s_r_a,S_r_a);

+printf(" \n   b. %.1f + %.1f = %.1f \t\t %.3f \t\t %.1f ",R_r,R_x_b,R_r+R_x_b,s_r_b,S_r_b);

+printf(" \n   c. %.1f + %.1f = %.1f \t\t %.3f \t\t %.1f ",R_r,R_x_c,R_r+R_x_c,s_r_c,S_r_c);

+printf(" \n   d. %.1f + %.1f = %.1f \t\t %.3f \t\t %.1f ",R_r,R_x_d,R_r+R_x_d,s_r_d,S_r_d);

+printf(" \n  ___________________________________________________________________");