| 摘要 |
PURPOSE:To increase a motor torque at the time of emergency stop test without changing the size of a primary current by providing a switch to act at the time of an emergency stop test, a slip frequency vector control inverter unit, and a plurality of computers for computing the slip frequency. CONSTITUTION:When a slip frequency computer G1 for normal operation is used, a torque at the time of an emergency stop test becomes A, while if omegasT2 is small, the torque is increased to be the maximum at omegasT2=1. A secondary time constant T2 is a specific value to a motor, and it is a slip frequency omegas that can be controlled, so a computation gain for the slip frequency need be set small by a specified switch only at the time of the emergency stop test. This means that, at the time of an emergency stop test, a switch SW1 is actuated in an inverse direction prior to the test, and a signal from a torque command tauis computed by a second slip frequency computer G2 to determine the slip frequency omegas. A torque point is thus set at a point B, and the larger value than the torque A can be obtained while the current value is not changed. |
