Torque control apparatus for rotary machine.

摘要

A torque control apparatus for a compressor driven by a motor through a main shaft, in which variations of the rotation speed of the main shaft due to torque variations are detected at selected angular positions of rotation of the main shaft. Current values to be supplied to the motor for eliminating the rotation speed variations depending on the angular positions of rotation of the main shaft are computed and stored during at least one revolution of the main shaft, and, in the next revolution of the main shaft, that is, when the main shaft rotates then to a 360 DEG advanced angular position, the motor current is controlled on the basis of the current values supplied for at least one revolution of the main shaft, thereby eliminaitng variations of the rotation-speed of the main shaft.