Dynamic Performance of a Static Synchronous Compensator with Superconducting Magnetic Energy Storage

This paper discusses the integration of a static synchronous compensator (STATCOM) with a superconducting magnetic energy storage (SMES) system for controlling the frequency of large power systems (PS). At present, the new energy storage systems (ESS) are a feasible alternative to store excess energy for substituting the primary control reserve thus improving the primary frequency control (PFC). In this way, the performance of the STATCOM controller can be enhanced with the addition of the SMES coil through a dc-dc chopper. This combination allows to greatly improve the PFC and consequently the PS security. In this study, the dynamics of active and reactive power responses of the integrated STATCOM/SMES system to power system oscillations is analyzed. This analysis is performed for the case of a tie-line tripping on a test power system by using SimPowerSystems of MATLABtrade. This paper also discusses the detailed modeling of the STATCOM based on a multi-pulse voltage source inverter composed of three-level elementary inverters, the two-quadrant multi-phase dc-dc chopper and the SMES coil. Finally a multi-level controller is presented for the integrated compensator by using concepts of instantaneous power on the synchronous-rotating d-q reference frame