Hi everyone,
Let’s say I’m using a 3-phase FOXESS hybrid inverter and an EP11I/EP12 battery.
I have a question about the reaction speed of the system when handling sudden power demands, especially from PWM-driven loads like induction cookers (or other appliances with rapidly fluctuating power usage).
Specifically, I’m wondering:
How quickly does the system switch between charging and discharging modes (battery-wise) when there’s a spike or surge in power demand?
For example, let’s say I have 4kW solar producing power, an average 2kW load, and thus the battery charging at 2kW. If a short load spike suddenly happens and surges by another 5kW [ 15sec on 50 sec off ] (total load now becomes 7kW), with only 4kW solar available, the system would need an additional 3kW for about 15 seconds. In this case, would the battery handle this surge, or would the system pull from the grid instead? ( yes took easy numbers to explain the case real loads will be different)
Has anyone had experience with this, or does anyone have any technical details on how the system manages these types of peak loads?
Additionally, technically, would this damage the battery if the system needs to handle such surges for hours and hours ?
Any insights would be greatly appreciated!
Thanks in advance!
Noel
I don't have a 3-phase inverter, but KH7 with EP11.
They should act similar really.
There will always be a lag with any inverter before it reacts, though I find it quick to respond. I have an electric shower and the demand hits 10kW, the battery will quickly supply upto 7kW (depending on how much solar generation) and the grid fills in the remaining 3kW.
A cooker going on and off reacts the same.
I always think of the electric as waves on a beach, with a sort of "ebb and flow" so if you are in your example producing excess solar, then you are "pushing" against the ocean to export, once you demand more local power, the waves come rushing in to fill the gap.
I am sure the battery will survive this abuse, EV cars can pull several hundred kWs when sending it, and then regen back all day long.
They should act similar really.
There will always be a lag with any inverter before it reacts, though I find it quick to respond. I have an electric shower and the demand hits 10kW, the battery will quickly supply upto 7kW (depending on how much solar generation) and the grid fills in the remaining 3kW.
A cooker going on and off reacts the same.
I always think of the electric as waves on a beach, with a sort of "ebb and flow" so if you are in your example producing excess solar, then you are "pushing" against the ocean to export, once you demand more local power, the waves come rushing in to fill the gap.
I am sure the battery will survive this abuse, EV cars can pull several hundred kWs when sending it, and then regen back all day long.
Yes, that’s the question: How long (or how big, time-measured = reaction speed ) is this lag, when switching from charging to discharging and vice versa?
I would like to have some specific numbers or timeframes here.
This pattern has been the most resource-consuming for me over the past three years of monitoring various types of data.
The main concern is whether I can overcome these 'short' surge peaks and avoid paying grid prices, which are more than 20 times (in price value) the value ( for what i get back for ) what I inject.
I want to repeat once more: a surge peak lasts about 15 seconds, followed by 50 seconds of normal operation. This pattern continues for hours.
If the battery were charged in an ideal case [ fast switching, / allmost no lag ( < 1sec, ideal would it be 0 ( what is not possible i agree)] this pattern would be covered by the battery, and not by the grid.
If the INVERTOR-LAG ( charge vs discharge) is 15 seconds or more (in this specific case), adding batteries won’t solve anything.
Noel
I would like to have some specific numbers or timeframes here.
This pattern has been the most resource-consuming for me over the past three years of monitoring various types of data.
The main concern is whether I can overcome these 'short' surge peaks and avoid paying grid prices, which are more than 20 times (in price value) the value ( for what i get back for ) what I inject.
I want to repeat once more: a surge peak lasts about 15 seconds, followed by 50 seconds of normal operation. This pattern continues for hours.
If the battery were charged in an ideal case [ fast switching, / allmost no lag ( < 1sec, ideal would it be 0 ( what is not possible i agree)] this pattern would be covered by the battery, and not by the grid.
If the INVERTOR-LAG ( charge vs discharge) is 15 seconds or more (in this specific case), adding batteries won’t solve anything.
Noel