This paper presents the control system design for a battery/ultracapacitor experimental setup developed for the purpose of experimental characterization and modeling of battery and ultracapacitor-based energy storage systems. The setup comprises two IGBT-based two-quadrant DC/DC power converters. The low-level battery/ultracapacitor current controllers and the DC link voltage controller are implemented in a relatively inexpensive programmable logic controller (PLC), while the high-level control and data acquisition are based on the National Instruments DAQ board and National Instruments LabView software. The proposed test setup control system is verified experimentally for a wide range of operating regimes including preliminary battery/ultracapacitor experimental characterization tests.