Dynamic voltage compensators have been playing important role in the protection of sensitive loads against disturbances, as voltage sags and swells. One implementation option for such equipment is based on the use of a conventional three-phase inverter, which is not able to inject zero sequence components. This paper evaluates the performance of a dynamic sag compensator without zero sequence injection capability in the protection of sensitive loads. A full scale prototype (220V/250kVA) was implemented and some experimental results of its operation are included to support the theoretical analysis.