| 摘要 |
<p>PURPOSE:To enable to achieve the regenerative brake of an induction motor IM and to obtain a highly efficient regenerative characteristic by reducing the control value of the output current of the IM to the magnitude corresponding to the exciting current of the IM when the power voltage of an inverter is overvoltage state. CONSTITUTION:A deviation calculator 17 of a power source voltage and an overvoltage set value subtracts by a subtractor 18 the V output IV of the calculator 17 from a current pattern IP1 obtained via a torque command value T via a current pattern circuit 10 when the power source voltage VE becomes the set value or higher to subtract the current pattern IP=IP1-IV. Thus, a slip frequency is decreased to reduce a rotor current IR, and the input current of an IN can be decreased. The voltage VE can be reduced by decreasing the input current of the IM, thereby enabling to protect an inverter main circuit and the IM and to obtain highly efficient regenerative characteristic.</p> |
