pik1432

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These are questions asked by pik1432

Hello there, 

Would you allow me to a question regarding the correct way of using 'alias?

In the attached worksheet, an alias is defined, then a. the defined alias is not working (please have a look at the line with the same comment), b. the alias works in the other way around (please have a look at the line with the corresponding comment, Alias is working backward). When I tried to substitute the function with the 'subs' command (please have a look at the expression 'Desired'), then I was able to get the result, expected from alias command. 

Perhaps, I am confused with how the 'alias' command works. I would appreciate it if the correct way is explained. 

Thank you, 

In Kwon Park 

Maple Worksheet - Error

Failed to load the worksheet /maplenet/convert/Q20210724.mw .
 

Download Q20210724.mw

 

Hello there, 

While I was trying to calculate the complex (i.e., P and Q) power equations, I got this question. 

Thus, I wonder if I can have a chance to ask the question here:

a. When the voltage and current are defined as functions, taking the t (time) as a input variable, I was not able to get the proper outcome from the operation. Those attempts are labeled as '#1' and '#2' in the attached worksheet. 

b. When the voltage and current are defined as simple complex expression, I was able to see what I wanted. The expression is named as 'ideal' in the attached worksheet. 

c. Therefore, my question is to see if there is a way to make the operaion using the functions in the same way as done by the simple expressions. 

d. Any insight would be appreciated. 

Thank you. 

Q20210617.mw

Hello there, 

Would you allow me to ask this one question?

What is the difference between 'map' and '~(element-wise operation)'?

The following worksheet snipped shows an example:



Maple Worksheet - Error

Failed to load the worksheet /maplenet/convert/Q20210612.mw .
 

I thought that both operations were the same, but seemingly they are not. 

Best Regards, 

In Kwon Park 

Download Q20210612.mw

Hello there, 

Would you allow me to ask this question?

What I tried in the worksheet below is to map an expression to x-axis and another expression to y-axis, while both expressions have the same input (or independent variable). However, the resulting plot still shows those two expressions as two separate curves. Would you tell me how to map or assign the expressions to each axis?


 

restart;

with(LinearAlgebra):

Digits := 6:

j := I:

L__adpu := 1.66;
L__aqpu := 1.61;
L__lpu := 0.15;
R__apu := 0.003;
E__tpu := 1.0;
MVA := 555;

1.66

 

1.61

 

.15

 

0.3e-2

 

1.0

 

555

(1)

A__sat := 0.0312500:
B__sat := 6.93147:

I__tpu_compare := (P__t - j* Q__t) / E__tpu;

-(1.00000*I)*Q__t+1.00000*P__t

(2)

I__tpu_a := abs(I__tpu_compare);

abs(-(1.00000*I)*Q__t+1.00000*P__t)

(3)

Phi := arccos(P__t / (I__tpu_a * E__tpu));

arccos(1.00000*P__t/abs(-(1.00000*I)*Q__t+1.00000*P__t))

(4)

E__a__tilde := E__tpu + (R__apu + j * L__lpu) * I__tpu_compare;

1.0+(0.3e-2+.15*I)*(-(1.00000*I)*Q__t+1.00000*P__t)

(5)

psi__at := abs(E__a__tilde);

abs(1.0+(0.3e-2+.15*I)*(-(1.00000*I)*Q__t+1.00000*P__t))

(6)

psi__I := A__sat * exp(B__sat * (psi__at - 0.8));

0.312500e-1*exp(6.93147*abs(1.0+(0.3e-2+.15*I)*(-(1.00000*I)*Q__t+1.00000*P__t))-5.54518)

(7)

K__sd := psi__at / (psi__at + psi__I);

abs(1.0+(0.3e-2+.15*I)*(-(1.00000*I)*Q__t+1.00000*P__t))/(abs(1.0+(0.3e-2+.15*I)*(-(1.00000*I)*Q__t+1.00000*P__t))+0.312500e-1*exp(6.93147*abs(1.0+(0.3e-2+.15*I)*(-(1.00000*I)*Q__t+1.00000*P__t))-5.54518))

(8)

K__sq := K__sd;

abs(1.0+(0.3e-2+.15*I)*(-(1.00000*I)*Q__t+1.00000*P__t))/(abs(1.0+(0.3e-2+.15*I)*(-(1.00000*I)*Q__t+1.00000*P__t))+0.312500e-1*exp(6.93147*abs(1.0+(0.3e-2+.15*I)*(-(1.00000*I)*Q__t+1.00000*P__t))-5.54518))

(9)

X__ad := K__sd * L__adpu:

X__d := X__ad + L__lpu:

X__aq := K__sq * L__aqpu:

X__q := X__aq + L__lpu:

delta__i := arctan((X__q * I__tpu_a * cos(Phi) - R__apu * I__tpu_a * sin(Phi))/(E__tpu + R__apu * I__tpu_a * cos(Phi) + X__q * I__tpu_a * sin(Phi))):

e__q := E__tpu * cos(delta__i):

i__d := I__tpu_a * sin(delta__i + Phi):

i__q := I__tpu_a * cos(delta__i + Phi):

i__fd := (e__q + R__apu * i__q + X__d * i__d)/(X__ad):

i_armature := sqrt(i__d^2 + i__q^2):

i_armature2 := subs(P__t = 0, i_armature):

i_armature3 := subs(P__t = 0.5, i_armature):

i_armature4 := subs(P__t = 1.0, i_armature):

plotA := plot(i_armature2, Q__t = -0.6..0.6):

plotB := plot(i_armature3, Q__t = -0.6..0.6):

plotC := plot(i_armature4, Q__t = -0.6..0.6):

plots:-display([plotA, plotB, plotC]);

 

i__fd2 := subs(P__t = 0, i__fd):

i__fd3 := subs(P__t = 0.5, i__fd):

i__fd4 := subs(P__t = 1.0, i__fd):

 

plotD := plot(i__fd2, Q__t = -0.6..0.6):

plotE := plot(i__fd3, Q__t = -0.6..0.6):

plotF := plot(i__fd4, Q__t = -0.6..0.6):

plots:-display([plotD, plotE, plotF]);

 

plot([i__fd2, i_armature2, Q__t = -0.6..0.6]); #failed, two expressions are plotted seperately.

 

 

 


Best Regards, 

In Kwon Park 

Download Q20210416.mw

Hello there, 

Would you tell me how to treat differentiation as an operator?

Here is a simple example:

(The content of the worksheet is supposed to be here, but that did not work)

Download Q20210407.mw

The 'coeff' operation shows 'psi__d0' as the only coefficient of 'Delta__delta(t)', while what I wanted to see is the 'Desired' expression in the worksheet, '(psi__d0 + psi__q0 / omega__0 * D)' as the coefficients. Here, 'D' represents the differentiation. 

Thank you, 

In Kwon Park 

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