how can I overcome on algebraic loop in simulink

I faced error in simulink when I use PV-block that located in renewable library which developed by mathworks team- with inverter (power electronic) with powergui block (discrete mode time =1e-6) and the PWM in the inverter (5Khz)

I tried to install memory block and unit delay block around the error area which is in ( PV Array/Diode Rsh/Product5 ) but it doesn't work still the same problem

I tried to minimize the sampling time in powergui from 1e-6 to 1e-8 , it works but it takes very very long time even if the simulation stop time is 0.1 unit time

if anybody can helps me .... please i'm trouble

[Divya Yerraguntla]

Is the issue resolved with the provided solution?

[Rashed HD]

yes the algebraic loop resolved but another error poped up which is the following

(

An error occurred while running the simulation and the simulation was terminated

Caused by:

• Derivative of state '1' in block 'xxxxxx/PV three phase inverter/Mean/Model/integrator' at time 1.0 is not finite. The simulation will be stopped. There may be a singularity in the solution. If not, try reducing the step size (either by reducing the fixed step size or by tightening the error tolerances) )

https://www.mathworks.com/matlabcentral/answers/513187-how-can-i-overcome-on-algebraic-loop-in-simulink#comment_817875

Answer 1

[Pemendra Kumar Pardhi]

Dear,

Rashed,

Basialy algebric loop error occure in simulink model whenever zero is come in denomenator part of any function.

To ovecome the algebric loop error in simulink model due to -: PV Array/Diode Rsh/Product5.

follow two steps;

1. Double click to PV array > advanced > check to check box in break algebric loop in internal model
2. Go on the model configuration parameter model> zero crosing options > Zero-crossing control: Disable all

In this way your problem will be solved.

Thanks

Pemendra Kumar Pardhi

[Rashed HD]

thanks for your help Mr.Pemendra Kumar Pardhi algebraic loop error has resolved

but i'm concern if that method will affect the model results quality ?

also, there is another error has poped up which is the following

(

An error occurred while running the simulation and the simulation was terminated

Caused by:

• Derivative of state '1' in block 'xxxxxx/PV three phase inverter/Mean/Model/integrator' at time 1.0 is not finite. The simulation will be stopped. There may be a singularity in the solution. If not, try reducing the step size (either by reducing the fixed step size or by tightening the error tolerances) )

please if you can help

[Komal]

try changing the powergui to continous

Answer 2

[Divya Yerraguntla]

Hi Rashed,

1. This issue might occur when you are using the integrator block with 0 initial condition, try changing the initial condition to 0.0000001 instead.
2. Else, you could also try changing the Solver to ODE15s (stiff/NDF) under the Type : Variable Step in the Model Configuration Parameters/Solver/Solver Options

Hope it helps!

[Rashed HD]

Dear Mr. Divya Yerraguntla

thank you so much for your help, interest and patiance

but i tried this methoed many time and i tried to change solver types but it does not work also i tried to play with sampling time when i puted 1e-3 or lesser like 1e-4,1e-6 it gave the same pervious error (integerator ..... etc) while when i puted the sampling time greater than 1e-3 like 0.1 , 0.5 or 1 the simulation has worked for time 0.017 and it freezed without any progess i wait for more than 30 minutes but still the simulation time 0.017 no progress and no errors

what do yo suggest to solve ..... if you can help this will be highly appreciated

for contacts :[e-mail]

thanks again for allhttps://www.mathworks.com/matlabcentral/answers/513187-how-can-i-overcome-on-algebraic-loop-in-simulink#answer_423101

[ATHIRA E R]

Hi Sir,

I also followed the above steps and Im getting tha same error menioned above by RASHED MD. Can you help me to fix that error?