直列補償型SMESによる電力系統の安定化制御

抄録

In this paper, a combined controller of Superconducting Magnetic Energy Storage (SMES) with series compensator for the stabilization of power system is proposed. The apparatus injects voltage of variable magnitude and phase in series with a transmission line and it is capable of absorbing or releasing energy from a generator freely. A new control scheme of this controller for the power system stabilization has also been proposed here. Under normal condition, it is controlled in order to compensate reactance by injecting voltage which has phase lagging behind the line current by 90°. When a disturbance occur, injected voltage from phase shifter is applied to the damping control of generator swing and the voltage regulation by using new concept. The active power control is contributed to the generator terminal voltage regulation and the reactive power control is contributed to the damping control of generator swing. When a large disturbance occurs, it is controlled in order to absorb the accelerating energy from a generator by using superconducting coil. This new controller apparatus is expected to be a promising fault current limiter because during a short circuit, the output voltage from series compensator is insignificant compared with the voltage across leakage reactance of series compensator. As a result, the proposed controller is expected to improve steady-state stability as well as transient stability. The effectiveness of the proposed controller is evaluated from the viewpoints of current limiting, transient stability improvement and steady-state stability improvement based on numerical analyses.