Position control apparatus

A position control apparatus that performs quadrant inversion compensation when an axial moving direction of a machine is reversed, comprising:

• a control unit comprising:
• a reverse displacement calculation unit configured to calculate a reverse displacement that represents an amount of movement made from a preceding reverse point to a current reverse point by an axis that performs a reversing motion;
• a reversing-time segmenting number number of consecutive occurrences of reversing motions calculation unit configured to compare the reverse displacement to a predetermined value, and, when the reverse displacement is less than the predetermined value, increase a value of a reversing-time segmenting number of consecutive occurrences of reversing motions, which is a coefficient indicating a number of segments per unit time during a reversing motion, and, when the reverse displacement is greater than or equal to the predetermined value, decrease the value of the reversing-time segmenting number number of consecutive occurrences of reversing motions;
• and
• a quadrant inversion compensation unit configured to automatically adjust a quadrant inversion compensation amount according to the reversing-time segmenting number number of consecutive occurrences of reversing motions, and perform the quadrant inversion compensation based on the automatically adjusted compensation amount.