Abstract
Superconducting magnetic energy storage (SMES) is considered the next generation technology for storing electrical energy because its energy storage efficiency is higher than that of any conventional energy storage system and its charging and discharging times are short.
This paper discusses the input and output circuits of SMES for DC lines, and it discusses their circuit control methods. The main items in this paper are the follows:
(1) An input circuit using a high-frequency switching control method is proposed, and its stable condition (depending on the voltage range of the capacitor in the input circuit) is derived.
(2) A frequency modulation method for an output circuit is proposed, and simulated results show that this circuit supplies stable power and a constant ripple voltage.
(3) Experimental results of the input and output circuits using a normal-conducting coil and a current-generator are shown to confirm the analysis of the input and output circuits.
