Grid set point - how frequently can it be updated without causing issues?

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ronski asked Apr 10, '23

Grid set point - how frequently can it be updated without causing issues?

I'm currently writing a flow for scheduled discharge, as I want to discharge 4 kW from the batteries, I need to take into account AC loads and Total PV generation.

I currently have the flow working (although not updating the actual grid set point yet), and every second it calculates what the grid set point should be to ensure that the batteries are being discharged by 4 kW's.

However this will mean that the grid set point is changing every second, will this have any negative implications on the system?

ess discharging

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Answer 1 · 2023-04-19T20:26:33Z

ronski answered · Apr 19, 2023 at 08:26 PM

As I never got an answer to this, I change the calculation so that it is done every 15 seconds, I then further reduced the amount of times the grid set point is changed by adding a range, if the new set point is within the range then the set point is not changed.

See https://community.victronenergy.com/questions/200564/scheduled-discharge-flow-includes-charging-time-to.html

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Answer 2 · 2023-04-19T22:27:08Z

gerard-van-seventer answered · Apr 19, 2023 at 10:27 PM

I think 15 seconds is too fast. It takes time for the system to slowly adapt to the new setting as you can clearly see in the console. Personally I would wait at least a minute or more depending on the variation of the load.

To be honest I think whatever you try to accomplish you are on the edge of misusing the system.

btw, the new version 3.x should have a little more responsive ESS. You could try the beta or wait for the stable release.

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Answer 3 · 2023-04-20T05:49:00Z

ronski answered · Apr 20, 2023 at 05:49 AM

@Gerard van Seventer thanks for your reply, having monitored the system it take up to 15 seconds to ramp up or down. My routine does not change the setting every 15 seconds, I built in a range function, if I set the range to 500, then it is + or - 500, so if the calculated set point is within that range the actual set point will not be updated, this greatly reduces the amount of times the actual set point is changed.

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