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frequency response

ptc-4563151
1-Visitor

frequency response

Hello,

I want the frequency response of F(s,Iabc).

I don't see why that don't to display.

Do you can to help me.

Thank you very much

ACCEPTED SOLUTION

Accepted Solutions

There are two ways to get a subscript:

If you want a subscript in a variable name, type "I.abc"

If you want to address an element of a vector, type "I[abc"

In your sheet you define i from 0 to 100 (an index variable) so don't type sx(i) {this defines a function}, type "sx[i", and sx becomes a vector of frequencies.

You need to read the help files about units--you're putting thrm in in some places and not others.

View solution in original post

10 REPLIES 10
Raiko
17-Peridot
(To:ptc-4563151)

Hello Julia,

I see several culprits in your worksheet:

#1 you haven't defined the variable Iabc. And you're using it on both sides of your equation.

#2 you're using min and max as avariable. These are however, MathCad functions and shouldn't be overwritten.

#3 the same applies to your function s(i). s is a unit in MathCad.

Hope this helps

Raiko

I have corriged the errors that you say to me but that don"t work.

Why ? Please

Raiko
17-Peridot
(To:ptc-4563151)

Hi

I've checked your new sheet but I don't understand what you are trying to do. Is I a fixed value such as I = 4 A? Is abc an index? And is Iabc a vector (7th element in vector I) or is it a literal index? It will work when you define Iabc properly.

Also, in your function F(sa, Iabc) you're calling sa which isn't defined.

Raiko

I try to reproduce the example on page 3-4 of this extract : ssm2040 filter analysis part 1 'write that in google and the first site internet.

Can you help me, please.

Thank you very much

Raiko
17-Peridot
(To:ptc-4563151)

Hello Julia,

sorry I didn't answer your question, but I was off for a few daysw.

Glad that Fred lent a helping hand

Raiko

There are two ways to get a subscript:

If you want a subscript in a variable name, type "I.abc"

If you want to address an element of a vector, type "I[abc"

In your sheet you define i from 0 to 100 (an index variable) so don't type sx(i) {this defines a function}, type "sx[i", and sx becomes a vector of frequencies.

You need to read the help files about units--you're putting thrm in in some places and not others.

A last question :

I want the cutoff frequency fc(Iabc) and

why f(sa,Iabc) is not the same curve as on page 4 ! In the documentation it comes down to 1 * 10 ^ -5!

Thank's for your help

Fc(Iabc) , i want frequency of 50KHz.

Please, Thank's you

julia svenina karlsson wrote:

Fc(Iabc) , i want frequency of 50KHz.

That's a job for a solve block.

You are a king, thank you Fred

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