| 摘要 |
<p>A vector controller in which a primary current is supplied to an induction motor depending upon an exciting current instruction and a torque current instruction, and a frequency is controlled based on the magnetic flux calculated from the voltage and current of the induction motor. In calculating the magnetic flux from the voltage, current and magnetic flux instruction signal of the induction motor using a primary delay circuit, the time constant of the primary delay circuit is set to be equal to the time constant of the secondary circuit of the induction motor in order to calculate the magnetic flux of the induction motor, and then the induction motor is vector-controlled based on the calculated result. This makes it possible to decrease phase error contained in the calculated value of secondary magnetic flux for the true secondary magnetic flux, and to control the torque maintaining precision.</p> |
