INPUT VOLTAGE FLUCTUATION COMPENSATION IN ELECTRIC MOTOR DRIVE

摘要

PROBLEM TO BE SOLVED: To regulate a speed signal depending on the fluctuation of DC link voltage by generating a speed signal by compensating for a digital speed value according to the digital kink voltage value, transferring the compensated speed signal to an electric apparatus controller and using the compensated speed signal for the control of the apparatus. SOLUTION: An analog/digital converter 26 samples a DC link voltage 24 periodically and converts the sampled voltage into an output digital link voltage value 28. A speed measuring block 18 receives a rotor sensor output signal 16 indicative of the position of a rotor 12 form a sensor 14. An actual rotor speed signal 20 from the speed measuring block 18 is corrected at a DC link voltage compensation block 22 according to the digital kink voltage value 28 to produce a compensated digital speed signal 30. The compensated digital speed signal 30 is transferred to a motor controller 32 which is thereby controlled. According to the arrangement, the rotor speed signal 20 can be regulated depending on the fluctuation of DC link voltage 24.