| 摘要 |
PURPOSE:To control the air flow according to each of various processes in an electric furnace and save electric power, by controlling both voltage and the frequency of an AC power supplied to an AC motor. CONSTITUTION:Setting devices 6-6'' are so set as to correspond to the amounts of dust generated in an electric furnace and selected according to the processes. The voltages and the frequencies of a forward converter circuit 2 and a reverse converter circuit 4, each forming an inverter, are controlled by the output from a ramp function generator 7 respectively. Accordingly, both the voltage and the frequency of an AC power 1 supplied to an AC motor 5 to drive an exhauster 16 are controlled so that the air flow of the exhauster 16 changes. Thus, the voltage and the frequency of the power supplied to the motor 5 are controlled according to the amounts of the dust generated in the respective processes. Accordingly, electric power can be saved largely. |
