| 摘要 |
A motor controller by which out-of-control can be correctly detected in a short time by a simple calculation using a controlled variable of a motor and the safety of a machine such as a crane can be improved. The coordinate system of the voltage and current of an AC motor are converted into a coordinate system of two axes (d, q) to control the AC motor, and out-of-control is detected from the d- and q-components of the voltage or current. Using the exciting current feedback value Id which is the d-component of the current and the torque current feedback value Iq which is the q-component, if a value computed according to thetai =tan<-1>(Iq/Id) increases above a predetermined value, the motor is judged to be out of control. |
