How to fix Index exceeds matrix dimensions error?

Kindly have a look at the errors.

Error in expression for 'project_wind/Wind Turbine/wind_speed^3', an input index exceeds its input width of 1

Error in port widths or dimensions. 'Output Port 1' of 'project_wind/Wind Turbine/Wind speed (m//s)' is a [1x1] matrix.

Answer 1

[Mathieu NOE]

hello Philip

I corrected some minor bugs in matlab function blocks

also lambda_nom is not initialized so I took lambda_nom = 1 to run the code

last point you have to fix is that when pitch_angle is zero , there are division by zeros in your cp(lambda,beta) block

all the best,

mathieu

[Philip Liju]

Thank you so much. I really appreciate it. Could you kindly export the file to 2020a and upload coz this file isn't opening for me

[Mathieu NOE]

here you are

[Philip Liju]

thank you

[Philip Liju]

When I'm calculating the mechanical power manually with the pitch angle = 0, I'm getting the mechanical power to be around 2.32 mW. Any idea where I'm making the mistake?

lambda nom = 8.1

[Mathieu NOE]

hello

I put some displays everywhere to see the magnitude of signals

again, the output of the cp(lambda,beta) block is very small

and that make the product output (power) also very small

I suspect there is a mistake in the cp(lambda,beta) block

[Philip Liju]

This is the data I used. It's taken from a text book

[Mathieu NOE]

ok

could you double check that the simulink block output i coherent with a matlab script ?

[Philip Liju]

I made some changes. But still I ain't getting the desired result. It's the error with calculating using the variables I guess. Kindly have a look

[Mathieu NOE]

hello

I wonder what the lambda and beta value should be in the inputs of that block

lambad is calculated from wind speed (12 m/s) with a gain block (parameter : lambda nom ) and you said that lambda nom = 8.1

so are we right here ? is lambda = lambda nom = 8.1 or lambda = wind speed x lambda nom = 92.7 ?

doing the cp calculation in matlab gives the following results

if lambda = lambda nom = 8.1 and beta = 0, cp = 0.3441

if lambda = wind speed x lambda nom = 92.7 and beta = 0, cp = -1.4944 (?? negative value)

also is beta unit = degrees ?

[Philip Liju]

I used this formula. Lambda nom is considered as the lambda from the equation = 8.1

[Mathieu NOE]

Ok

so I found the bug in the block cp(lambda,beta) : the indexes of u[ ] were incorrect

the script and simulink gives me now the same values

last point to check : so lambda = 8.1 if wind speed = 12 m/ s ? so i put the gain accordingly - check this please

attached the updated file

[Philip Liju]

This works as I want it to be. Thank you so much for your help .. Really appreciate it

[Mathieu NOE]

you 're welcome !