Singular matrix error when solving simple 6 bus system about pypower HOT 2 OPEN

Just to give a short update, the issue could be solved by simply modelling all other generators as negative loads. This might pose problems if more complex OPF calculations are to be made, which is however not the case for me.

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This is one major problem of PyPower. The Algorithm does not detect branches without anything connected.
What I'm trying to say is that when the last Bus of a strand has a total value of (0+j0)MVA the Jacobian cannot be inverted.
In the case above it would be Bus-4...

Simple Fix is to change all 0 values for P in ppc bus array to 1e-10

What should be done though is to automatically detect these branches/buses/generators and deactivate them. Before building the Jacobian.

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