This paper extends the virtual synchronous machine (VSM) concept, recently proposed as alternative means to synchronize grid-connected inverters, by developing a VSM-based STATCOM controller operating as synchronous condenser. To this end, a mathematical model is derived and used to analyze the inherent dynamics of the VSM-based STATCOM controller, which are then used to formulate design guidelines that further detach the proposed method from the perceived physical constraints introduced by the VSM concept.