Sinexcel inverter with battery

SvenAarts · December 11, 2023, 10:58am

Dear forum,

I have been trying to get a Sinexcel inverter running with a dyness battery.
I build everything myself and got the UI running however i cant get everything connected.
The Sinexcel is connected and is readable in openems ui over Modbus TCP.
Now i am trying to define an ESS in openems edge but i cant find how to define this and set it up. I tried the ESS generic managed Symmetric but than i need a battery ID. The battery connects to the inverter over RS485 cable and the inverter can read the BMS data. How do i define this battery in Openems? and how to setup a working ESS then?

With kind regards,

Sven

stefan.feilmeier · January 2, 2024, 9:46pm

Hi Sven,

see this diagram:

(original source: Edge-Module - Programmierstil - #2 by stefan.feilmeier)

For Energy Storage Systems OpenEMS distinguishes two architectures:

Direct ESS (“Ess.SMA.SunnyIsland” in the example). In this architecture you communicate only with the Battery-Inverter and it internally handles all the communication with the Battery.
Combination of Battery-Inverter and Battery (“KACO” + “BYD BatteryBox” in the example): Here OpenEMS communicates separately with Battery-Inverter and Battery.

In your case it sounds a lot like architecture (1). Unfortunately in OpenEMS the Sinexcel is only implemented for architecture (2) (i.e. the Sinexcel code implements BatteryInverter).

To continue with OpenEMS you have two variants:

Either convert the BatteryInverter implementation to an Ess implementation. See the GoodWe implementation as an example. It provides both variants with shared code in AbstractGoodwe.java → https://github.com/OpenEMS/openems/tree/develop/io.openems.edge.goodwe/src/io/openems/edge/goodwe
Or connect your OpenEMS directly to the Dyness battery and implement it separately.

Benefit of the second variant is, that you get full control over the battery behaviour and can most likely read more detailed data from the Battery directly.

Regards,
Stefan