| 摘要 |
PURPOSE: To suppress an unbalanced current by connecting each winding of a three-phase induction motor being installed, corresponding to each of the three-phase outputs of voltage type inverter circuits connected in parallel, with the outputs of the the voltage type inverter circuits, and detecting the currents applied to each winding, and balancing the currents of the same-phase windings. CONSTITUTION: A motor 42 is installed, being split with the combination of the windings 421u, 421v, and 421w of three phases of u, v, and w, and the neutral points of several windings are connected with one another. Voltage type inverter circuits (V1) 23 and 24 connected in parallel and the motor 42 are connected directly, and current detectors 61u, 61v, and 61w and current detectors 62u, 62v, and 62w are inserted between both. The output of the current detector is given to a current balancing circuit 7, and the correction signal 701 generated from the deviation detecting circuits 7u, 7v, and 7w of the current balancing circuit 7 is inputted into the drive circuits 232 and 242 of the inverter circuits 23 and 24. The switching element is driven so that the current of each phase of the inverter circuits 231 and 241 may be balanced. |
