I'll try to answer that.
Voltage baluns are designed to provide equal voltages on the
outputs, such as those needed for balanced antennas. They help to keep
the balance against external influences, such as nearby metal bodies
and such.
Current balun are used with unbalanced loads, such as windom
antennas, when it's needed to qeep the currents as equal as possible.
This is done in order to minimize radiation from the line, which is
more corrent dependent than voltage dependent.
Choke baluns serve to break the path between the load and the
source so as to prevent energy to flow in a common mode fashion aleng
the line (usually from the load to the source). the name itself-the
full name, that is- " common mode choke" is self explanatory.
Alex 4Z5KS