Help needed - SMA, Solar Edge, Kostal and others

Beta testing Venus OS beta testing
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I’m experiencing issues with the export limit and peak shaving feature in my ESS setup, which consists of 3x MultiPlus II, Victron Energy Meter EM540, and PV systems connected to both AC-IN and AC-OUT. My goal is to maximize both my solar export and my PV peak installation, while limiting the grid current to 16A per phase (three-phase) for both export and import.

To achieve this, I’m trying to optimize my system to:

  1. Maximize my solar export within the grid limits (16A per phase)
  2. Maximize my PV peak installation

Initially, I throttled the maximum PV inverter power to 11500W combined using the Power Limit feature in the SolarEdge inverters (one to max 5000W and the other to 6500W). Now, I’m testing with Venus 3.6 to dynamically adjust the PV output based on grid demand. While the dynamic power limiting works with the SunSpec protocol, I’m having issues with the peak shaving feature.

When I set the Maximum system export current (per phase) to 11A (to stay safely within the limit of 16A per phase) and the Grid current limit to 11A I expect the system to:

  • Limit the export to 11A per phase
  • Try to achieve the Limit system feed-in (Maximum feed-in) - 11500W (~16A)

However, I’ve observed the following issues:

  1. With an uneven load on AC-OUT, the system tries to maintain a total export of 33A (3x11A), ignoring the grid current limit (set to 11A as a test).
  2. If there’s no load on one of the three phases, the other two phases exceed the 11A limit. For example, if Phase 1 has no load, Phases 2 and 3 will export more than 11A, even though the total export across all phases is still within the expected limit.
  3. It appears that the system is trying to achieve the maximum feed-in within the limits of the AC export limit (total of the three phases combined), rather than strictly adhering to the per-phase limit.

This behavior persists regardless of whether I set Multiphase regulation to Total of all phases or Single phase. I’m struggling to understand why the system isn’t respecting the per-phase export limit, especially when there’s an uneven load or no load on one of the phases.

Doing something wrong here?