| 摘要 |
<p>PURPOSE: A vector control system of an induction motor is provided to stably perform speed sensorless vector control of the induction motor within a low velocity period, allow high accurate velocity and torque control, and automatically compensate motor constant change and voltage error within a low velocity period. CONSTITUTION: A vector control system of an induction motor comprises a velocity controller(2) for subtracting an estimated speed from a reference speed, a torque portion current controller(3a) for subtracting a torque portion current from the output of the controller(2), a magnetic flux controller(13) for subtracting an estimated magnetic flux from a reference magnetic flux, a magnetic flux portion current controller(3b) for subtracting a magnetic portion current of the reference magnetic flux plus an offset current from an actual magnetic flux portion current, a motion/standing coordinate converter(4) for converting a motion coordinate voltage to a standing coordinate voltage, a 2/3 phase coordinate converter(5) for 2-phase voltage in the standing coordinate to 3-phase voltage, an inverter(7) for driving the induction motor(6) using the 3-phase voltage and a DC link sensing voltage, a current detector(8) for detecting the 3-phase voltage, a standing/motion coordinate converter(10) for converting the 3-phase voltage to a motion coordinate current, a first resistance estimator(12) for estimating a first resistance using the motion coordinate current, and a magnetic flux and speed estimator(11) for estimating slip angle velocity from the q-axis current of the motion coordinate current.</p> |
