Compressor driving apparatus and refrigerator including the same

A compressor driving apparatus comprising:

• a compressor including a cylinder that has a discharge end for discharging fluid in the cylinder, a piston disposed in the cylinder and configured to perform a linear motion in a direction toward the discharge end, and a motor configured to drive the piston;
• an inverter including a plurality of switches, the inverter being configured to convert direct current (DC) power into alternating current (AC) power and to output the converted AC power to the motor;
• an output current detector configured to detect an output current flowing through the motor;
• and
• an inverter controller configured to control the inverter based on the output current, wherein the inverter controller is configured to:
• calculate a reference position of the piston based on the output current,
• calculate a push amount of the piston based on a change rate in an operation rate of the compressor being equal to or greater than a predetermined value, the push amount of the piston representing a displacement of the piston pushed by the fluid based on a stroke of the piston,
• calculate a current position of the piston based on the push amount of the piston, and
• output a switching control signal based on the current position and the reference position of the piston.