A potassium channel protein that has voltage-gated potassium channel activity. A voltage-gated potassium channel enables the transmembrane transfer of a potassium ion by a voltage-gated channel. A voltage-gated channel enables the transmembrane transfer of a solute by a channel whose open state is dependent on the voltage across the membrane in which it is embedded. [ http://amigo.geneontology.org/amigo/term/GO:0005249 PRO:XQ ]