| 摘要 |
PURPOSE:To enable to preferably perform a load equilibrium control by detecting the powers of a plurality of motors, and correcting the voltage or frequency reference by the largest power value. CONSTITUTION:The powers P1, P2 of induction motors M1, M2 obtained by multipliers 4, 8, respectively are added to an operational amplifier 9 through positive and negative polarity diodes D1, D2, the absolute values of the powers P1, P2 are compared by the amplifier 9 to discriminate the magnitudes of them. The power of the motor of larger absolute value is inputted to a calculator 5 as a correction signal to correct the voltage or frequency reference of a VVVF inverter INV, thereby controlling the inverter INV. Thus, even if a malfunction occurs in the step of controlling a load, a load equilibrium control can be preferably performed. |
