Power System Transient Stability Enhancement by Coordinated Control of SMES, SFCL & UPFC
Transient stability is the ability of the power system to remain in synchronism when subjected to a large disturbance. It is well known that the Superconducting Magnetic Energy Storage (SMES) is effective to damp the power swing after the occurrence of faults. But, if SMES is used for achieving high stabilizing effect, a large power capacity of SMES is required. Additionally, the SMES is not able to absorb enough energy during faults since the bus voltage where the SMES is installed, drops considerably. To enhance the SMES control effect and transient stability, this paper proposes the coordinated control of the optimized resistive type superconducting fault current limiter (SFCL) and SMES. When the fault occurs, the SFCL rapidly suppresses the transient power swing by limiting the fault current. When the short circuit occurs, the SFCL absorbs the generator accelerating power and supports the SMES to stabilize the power swing. By incorporating UPFC along with this arrangement, robust power system stabilization is achieved. This paper presents the coordinated control of resistive type SFCL , SMES and UPFC for an improvement of power system transient stability. Nonlinear simulation study in a single machine infinite bus system shows that the control effect of the coordinated SFCL, SMES and UPFC is much superior to that of the individual SFCL, SMES or UPFC.
Athira.B, Filmy Francis