| 摘要 |
PURPOSE:To suppress the ripple of a torque generated by an induction motor to a minimum value by operating a DC voltage generating section and inverter section in accordance with a value found from a specific calculating formula. CONSTITUTION:A control section decides voltage vector time widths TW1 and TW2 to be impressed based on a formula and, at the same time, decides the DC stage voltage Vdc1 and Vdc2 of an inverter based on formulae, Vdc1= SQR(3/2).omega1.phi2/cos(pi/6+theta) and Vdc2=SQR(3/2).omega1.phi2/cos(pi/6-theta) (where, phi2, omega1 and theta respectively represent a secondary cross flux, the angular velocity of the secondary cross flux phi2, and the angle indicating the position of the secondary cross flux phi2) and operates a DC voltage generating section and inverter section in accordance with the decided values so that the rotating speed and generating torque of an induction motor can always coincide with commanded values. |
