How to calculate the settling time for the PV MPPT controller?
I mean for example if the operating conditions are changed: solar radiation, the duty cycle, etc.
How much time the does system need to reach the steady-state condition?
In testing the MPPT controller speed of response one applies normally a unit step change of the Irradiance and see how it takes to reach steady state condition. The settling time is time taken by the processor from instant of application of stimuli till it reaches almost steady state value. The almost steady state value is considered to be reached when the power reaches its 90 percent of its steady state value.
Best wishes
Is this a serious issue or is it just an exercise? The time constants associated with changes in sun irradiance are tens of seconds, and I don't believe ANY MPPT is going to be that slow.
The time constant of PV module is inversely proportional to irradiation level. As decrease in irradiation level causes increase in time constant. Time constant increases with degradation of Series resistance (Rse) and shunt resistance (Rsh) of PV Panel.
Tony Maine V Veera Nagireddy If the duty cycle of solar radiation changes, the PV system needs time to reach the power output corresponding to that duty cycle or solar radiation. I need to calculate that time.
Thanks
As I said earlier, the change in solar irradiation will take typically a few seconds, depending on the cause. If it's due to clouds, irradiation will drop by about 85% in 5 seconds or so. If due to shadowing from a fixed object, it will take about 2 minutes (the length of time for the sun to 'move' across the skydome by its own angular diameter. In neither case should the MPPT take more than 1 second to adapt to the new conditions - so the overall time would be about (5^2+1^2)^0.5 seconds or about 5.1 seconds. The MPPT time constant will not be significant for such real world conditions. Best wishes with your research!
In testing the MPPT controller speed of response one applies normally a unit step change of the Irradiance and see how it takes to reach steady state condition. The settling time is time taken by the processor from instant of application of stimuli till it reaches almost steady state value. The almost steady state value is considered to be reached when the power reaches its 90 percent of its steady state value.
Best wishes
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