The ornamental design for a portablevoltagetransformer, as shown and described.
FIG. 1 is a perspective view of the portable voltage transformer of the present invention;
FIG. 2 is an end view of the portable voltage transformer as shown in FIG. 1;
FIG. 3 is an end view of the portable voltage transformer as shown in FIG. 1 opposite from the view shown in FIG. 2;
FIG. 4 is a side view of the portable voltage transformer as shown in FIG. 1;
FIG. 5 is a side view of the portable voltage transformer as shown in FIG. 1 opposite from the view shown in FIG. 4;
FIG. 6 is a top plan view of the portable voltage transformer as shown in FIG. 1; and,
FIG. 7 is a bottom plan view of the portable voltage transformer as shown in FIG. 1.
The broken lines shown represent unclaimed subject matter and form no part of the claim. Where broken lines abut shaded claimed surfaces it is understood that those broken lines represent an unclaimed boundary between claimed and unclaimed surfaces. None of the broken lines form any part of the claimed design.