| 摘要 |
<p>A system, for melting metal and holding molten metal at pre-selected temperatures, comprises a rectifier unit (12) receiving AC electric power (16) and outputting DC electric power, a plurality of inverter units (14), each receiving the DC electric power output from the rectifier unit (12) and outputting AC electric power; and a plurality of induction furnaces (20) each receiving the AC electric power output from a respective inverter unit (14). Each inverter unit (14) comprises a plurality of inverter modules (24) connected in parallel or other suitable configuration; each module (24) independently being connectable to and disconnectable from the rectifier unit and the furnace. The rectifier unit (12) comprises a plurality of rectifier modules (22) connected in parallel or other suitable configuration, each module independently being connectable to and disconnectable from the AC supply and the inverter units (14). Generally, the total power output of the rectifier unit (12) is greater than the sum of electric power required by the total of all of the furnaces (20) if they are all holding a charge of molten metal at a pre-selected temperature, but less than the sum of the maximum power consumption required by the total of all of the furnaces (20) if they are all melting a charge of metal. If the total power demand is greater than the rectifier unit (12) can supply, the power to those furnaces (20) receiving more than the holding power supply is reduced.</p> |
