1993 Volume 113 Issue 7 Pages 760-767
This paper represents the basic studies on the application of SMES (Superconducting Magnetic Energy Storage) to the energy storage for WECS (Wind Electric Conversion System). The WECS assumed in this study is the combination of a self-excited induction generator and DC link system (AC-DC-AC interconnection). By introducing a superconducting coil into the DC portion of the link system, it becomes possible that the fluctuation of the output power from the wind generator due to the wind speed variation is suppressed with the angular velocity of the wind turbine controlled at the maximum output point. Also, the proposed circuit can be used as a normal SMES when the WECS is out of operation.
First of all in this paper, the excitation characteristics of the self-excited induction generator is calculated, and it is made clear that the adjustment of the capacitance is necessary for the high efficiency operation of WECS. Next, the calculation of energy storage to the superconducting coil from the induction generator is done, and a step-down chopper is found required in order to adjust the generator current to the coil current. Furthermore, the conditions are derived for the proposed WECS + SMES to be operated at the maximum output angular velocity under the given wind speed.
The transactions of the Institute of Electrical Engineers of Japan.B
The Journal of the Institute of Electrical Engineers of Japan