Rolling Blackout Detector (Experiment)

petum said:
Sideline...

Why would an inverter do this?

Surely use solar much as possible when available and charge battery?

My axpert does the same thing.. Very annoying.
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I think he was talking about substations. What does your inverter do?
 
petum said:
Sorry was referring to inverter. Note that solar and ac are available but its using the battery.
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Normally only uses utility when it reaches a certain percentage, solar does that when massive cloud cover hit there was just no pv. So I set it up to run off utilities
 
TheChamp said:
It's probably some setting, it should be able to to use solar as long as it's available.
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Though I've had it on occasion where I need to flick off solar for ten minutes and click it back. Apparently a bug in the firmware from what I've seen on powerforum
 
Lupus said:
Though I've had it on occasion where I need to flick off solar for ten minutes and click it back. Apparently a bug in the firmware from what I've seen on powerforum
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I see the load just happens to be low at the time, I wonder if it would do that if there was some serious load on it.

Hopefully there's probably some way to tweak some of the settings to mitigate against it even if it's a firmware bug.
 
petum said:
Can view historical voltage using home assistant and hz if you need more?

729c4476e0c6d94f748dc8099aca35f0.jpg
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Thanks, it's the Hz that I'm after.
 
TheChamp said:
I see the load just happens to be low at the time, I wonder if it would do that if there was some serious load on it.

Hopefully there's probably some way to tweak some of the settings to mitigate against it even if it's a firmware bug.
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Well I've had it click over when it was charging the batteries at 3.6kw, with a load of 50% and in the photo after a cloud moved over.
It isn't consistent
 
petum said:
Sorry was referring to inverter. Note that solar and ac are available but its using the battery.
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I think it's this thread, maybe it will work for you but they were talking about the Axpert King.

Why not a Kodak Inverter

To all the Inverter experts: Why not choose a Kodak inverter, why choose something like the Deye or Sunsynk over a Kodak? The ones that i am comparing are the Kodak OG-7.2 and the Deye/Sunsynk 8kW, their technical specs seems to be nearly similar.
mybroadband.co.za mybroadband.co.za
 
wingnut771 said:
Look at thermal generation its the same all the time, it's not ramped up, the black part of the graph is thermal excl pumping, so they pump water back overnight lowering the graph.

It looks like they went hard with pumped storage and diesel the day before and ran out as they're about 1GW less on coal:
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I don't understand, so please humor me and explain like I'm a five year old.

You only have three data points, are they measurements on the hour or an average of the previous hour?

What if two units went down just after 04:00 and the output of the remaining units was increased to match the largely unchanged demand. Two more units go down just after 05:00 and the output of the remaining units was increased to their maximum output, coincidentally roughly matching the previous output?

By 05:00 hydro and pumped water generation has increased to over 1.9GW, OCGT production is being ramped up too. At this point they're not going to be able to meet the projected demand during the morning peak and will have to implement load shedding.

By 05:30 we have loadshedding and supply of hydro and pumped generation has been reduced, not because it's run out, but because it's much faster than reducing output from a coal plant. Demand is being met and it's safer to keep these in reserve.

At 06:00 OCGT output is over 2GW, so no shortage of diesel.

Long story short, I don't see how you can draw conclusions from that data. What was the maximum output from coal on each day? Were the available coal plants run at their maximum outputs on the 17th? What about on the 18th?
 
Ϲhristopher said:
I don't understand, so please humor me and explain like I'm a five year old.

You only have three data points, are they measurements on the hour or an average of the previous hour?

What if two units went down just after 04:00 and the output of the remaining units was increased to match the largely unchanged demand. Two more units go down just after 05:00 and the output of the remaining units was increased to their maximum output, coincidentally roughly matching the previous output?

By 05:00 hydro and pumped water generation has increased to over 1.9GW, OCGT production is being ramped up too. At this point they're not going to be able to meet the projected demand during the morning peak and will have to implement load shedding.

By 05:30 we have loadshedding and supply of hydro and pumped generation has been reduced, not because it's run out, but because it's much faster than reducing output from a coal plant. Demand is being met and it's safer to keep these in reserve.

At 06:00 OCGT output is over 2GW, so no shortage of diesel.

Long story short, I don't see how you can draw conclusions from that data. What was the maximum output from coal on each day? Were the available coal plants run at their maximum outputs on the 17th? What about on the 18th?
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Thermal generation is coal, units going down would show a bit dip, and recovery would be a few hours as it can't ramp up 1200Mw in an hour.
 
Ϲhristopher said:
I don't understand, so please humor me and explain like I'm a five year old.

You only have three data points, are they measurements on the hour or an average of the previous hour?

What if two units went down just after 04:00 and the output of the remaining units was increased to match the largely unchanged demand. Two more units go down just after 05:00 and the output of the remaining units was increased to their maximum output, coincidentally roughly matching the previous output?

By 05:00 hydro and pumped water generation has increased to over 1.9GW, OCGT production is being ramped up too. At this point they're not going to be able to meet the projected demand during the morning peak and will have to implement load shedding.

By 05:30 we have loadshedding and supply of hydro and pumped generation has been reduced, not because it's run out, but because it's much faster than reducing output from a coal plant. Demand is being met and it's safer to keep these in reserve.

At 06:00 OCGT output is over 2GW, so no shortage of diesel.

Long story short, I don't see how you can draw conclusions from that data. What was the maximum output from coal on each day? Were the available coal plants run at their maximum outputs on the 17th? What about on the 18th?
Click to expand...
I admit, they are averages but look at the reserves used on Monday vs Tuesday. Monday they were used like baseload but not Tuesday. They managed no stages on Monday but with only 1GW less they suddenly have to go to stage 4, why not stage 1?:
Untitled.png

I guess the 1GW missing is the 5 units so I've answered my own question and am just venting out of frustration and that we should have been at higher stages before Tuesday but Eskom were just running emergency reserves hard to hide it.

As to why these units tripped, it's probably the low frequency that caused it while they were using diesel to pump the water back because coal was already maxed out and didn't burn more diesel to increase the frequency.
 
Anyone able to post their data around last nights "Stage 4 with immediate effect"?
 
Not sure what happened around 22:20. But looks like a single data point.


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