3 Phase inverter true 0 export limitation

Hello all!

This is my first post here and I'm sorry it comes as a question/ problem.

I installed at my house a Huawei SUN2000-5KTL-M0, 3 phase inverter with 20 280W PV panels, divided into 2 strings. Also I installed a Smart Power Sensor (DTSU666-H) in order to limit the energy export to the grid.

All things are installed corectly, as per the instalation guide, checked and double-checked, and functional.

The export limitation is set to 0. I'm not a prosumer yet and the grid meter is a digital, one directional, standard 3 phase meter.

Now I encounter the next problem:

With Total Power export set to 0, the grid meter still registering consumption even if the FusionSolar app shows that the inverter is producing enough total power to cover the loads. Problem that I found is that the smart meter DTSU sums all the loads and tell the inverter to produce only that power (which is good), but the inverter splits the output power into 3 equal parts over all the phases. But on a regular house you almost never get to have same power demand from loads over those 3 phases. 

For example let's thake this scenario: 

                LOADS      PRODUCTION     GRID METER

Phase 1 - 3 KW          - 1,1 KW               - 1,9 KW import

Phase 2 - 0,2 KW       - 1,1 KW               - 0,9 KW export

Phase 3 - 0,1 KW       - 1,1 KW               - 1 KW export

Total         3,3 KW          3,3 KWh               3,8 KWh

The grid meter is registering a total of 3,8KWh, because it count the export as import. So even if the inverter is set to 0 export and it produces the total energy for the load demand, because it is split equal betwen the pahses this problem apeears. In this case I have to pay 3,8KW for the 3,3 I used in reality.

I also tried with Single Phase export  set, but this tells the inverter to produce power as per the minimum demand of the pahses:

                LOADS      PRODUCTION     GRID METER

Phase 1 - 3 KW          - 0,033 KW               - 2,967 KW import

Phase 2 - 0,2 KW       - 0,033 KW               - 0,167 KW export

Phase 3 - 0,1 KW       - 0,033 KW               - 0.067 KW export

Total         3,3 KW          0,1 KWh                   3,201 KWh

This is better, but as you can see it is not the desired efect. 

All of this is because the inverter does not deliver the power differently as per demand on the phases. On top of that the 5KTL-M0 at it's maximum output power, only put's 1.66666 on each phase. 

And now my question: Is there a way to set the Inverter to output the power different on each phase? 

If not my only solution will be to replace it with a 1Phase inverter and put all the loads of the house on just one phase. 

Thank in advance for you help.

Alex.