Does the problem "partition a vertex-weighted graph into $k$ balanced connected parts" have a standard name?
The paper [Chlebikova, Approximating the maximally balanced connected partition problem in graphs, 1996] studies a related problem: They have $k=2$, and they maximize $\min(|V_1|,|V_2|)$. It should be a good place to start searching for related results, by following the citation graph.