SolarEdge: Dynamic Active Power Support

[kerborous]

Does solaredge-modbus-multi integration support Dynamic Active Power capability?

SolarEdge inverters support Power Control protocol with compatible firmware such as the SE5000H. It is specifically intended for real-time solar curtailment by an external Energy Management System (EMS) ie HomeAssitant.

I am in Australia and this is particularly important in summer when the grid price goes negative and exporting energy costs the consumer. So when my batteries become full and we have a negative kWh/$ I must stop exporting.

My reading suggests the following Modbus register value process

Write 1 to F300 (Enable Dynamic Power Control).
Set F310 to a timeout, for example 10 seconds.
Set F312 to a sensible fallback (often 100%).
Write 70.0 (Float32) to F322.

The inverters will then limit total output to approximately 70% of rated power.

Important implementation details.
F322 is a Float32 value.
It occupies two consecutive Modbus registers.
It must be written using Modbus Function Code 16 (Write Multiple Registers).
The registers use SolarEdge's specified word order (little-endian word order for the 32-bit value).

Dynamic means this register is intended to be updated continuously by an EMS (HA). If you set Command Timeout = 10 seconds, then my controller should refresh F322 at least every 5 seconds (or faster). If updates stop, the inverter automatically reverts to the Fallback Active Power Limit configured in F312.

In my two-inverter system (2 xSE5000H) the intended approach would be:

Enable Dynamic Power Control on the lead SE5000H inverter.
Write the Dynamic Active Power Limit to the leader inverter.
The leader will broadcast the dynamic command to its follower(s) over the RS485 leader/follower network.

This is generally preferable to repeatedly writing to the persistent Active Power Limit register, because the dynamic registers are specifically designed for frequent, real-time updates by an EMS. No need to worry about registers wearing out flash memory :).

[bouwew]

Did you try my Automation: #1004

[kerborous]

I had a brief look at your code and wasn't sure if you were using the SolarEdge registers F300, F310, F312 and F322 Modbus parameters to ensure non-volatile memory longevity.

I did see the use of number.solaredge_i1_active_power_limit but maybe I miss something?
Noting that Flash and EEPROM memories typically support only a fixed number of write operations.

Can you clarify?

[bouwew]

The key take-away of my starter-post in #1004 is that you can change the number.solaredge_i1_active_power_limit to control the output of the SolarEdge 4000 inverter. I read in a different post somewhere in this github that you can change that number regularly without any memory longevity risk.

This picture shows the result in my home for today, various power sources have been running today, washing machine, dryer, airco:

And this picture shows the controlled AC ouput of my SolarEdge:

At the first large dip in the trace, just before 1pm, is where/when I enabled the automation.
It has been very sunny today, all day, no clouds, you can image how much solar power I'm blocking from being exported with this automation 🙂

[WillCodeForCats]

Yes it's supported.