Voltage Rating Reduction of Magnet Power Supplies Using a Magnetic Energy Recovery Switch

A new concept of magnet power supplies that can reduce voltage ratings of the power supplies is proposed. Circuit diagram and operation principles of magnetic energy recovery switch (MERS) are described. MERS consists of a capacitor and four semi-conductor devices such as MOSFETs and IGBTs. It is connected in series to a power supply and a coil. MERS is a switch module and it has no power supply in itself. Because MERS generates a voltage required for the inductance of the coil, the power supply only has to supply a voltage required for the resistance of the coil. Therefore, using MERS can reduce voltage rating and capacity of the power supply. Two types of power supply using MERS and voltage rating reduction are discussed. Comparatively small power supplies for high-repetition pulsed magnets and alternating magnetic field coils can be designed. Some experiments were carried out and confirmed that MERS can reduce voltage ratings of power supplies