Why in Flux should I not use 3 phase current source in star connection?

The analysis methods for describing the equation corresponding to the electrical circuit (mesh current method in Flux 2D and method of the node integrated potentials in Flux 3D) does not allow the representation of a Y–connected three-phase current source by its real schematic.

This problem can be overcome by removing one current source (see figure below). This will impose the correct values of the current

Another solution is to place a very high resistance in parallel, as it is shown in the figure below.