Can a PV Array be simulated with partial shading , without using bypass diodes?
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I have been trying to do some simulations on Simulink on a 3s2p PV configuration, without using bypass diodes and keeping different shading levels.
I keep 5 modules at 1000 W/m2, and vary irradiance on one module from 1000 and lower. I'm able to simulate till 944 W/m2 but below this level, I get singularity issues that I'm not able to solve. The error i get is as below:
Derivative of state '1' in block 'solarmodulesShadingAalysisInternally/PV Array1/Diode Rsh/Transfer Fcn' at time 0.0 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)
My question is: is it possible to simulate PV array without bypass diode? or if it is possible what could e the reason that i get this error.
Joel Van Sickel on 9 Nov 2022
This is likely caused by the fact that the solar model is often implemented as a controlled current source. Having multiple controlled current sources in series can always be tricky as it's not mathematically possible to simulate them unless they all output the same value of current. The bypass diode solves this issue, but you could also put a larger resistance in between the nodes of the solar panel. This will slow down the simulation and is less than ideal but could get you around your problem. The smaller the resistance, the faster the simulaiton will run, but the less accurate it will be.