System and method for controlling linear compressor

A method for controlling a linear compressor for generating a freezing force as a piston reciprocates according to rotation of a motor which receives alternating current power through a triac, the method comprising:

• detecting motor current and motor displacement of the motor when the linear compressor is driven;
• determining whether a center point of piston reciprocation is a resonant point based on the detected motor current and a phase difference of the motor displacement;
• and
• moving up or delaying a trigger signal corresponding to an absorption cycle or a compression cycle to be applied to the triac, if the center point of the piston reciprocation is not the resonant point.

A system, comprising:

• a motor;
• a linear compressor having a piston reciprocated by rotation of the motor;
• and
• a controller to move a center point of piston reciprocation to a compression cycle side or to an absorption cycle side of the piston to coincide with a center of teeth of a stator of the motor, and to perform a resonant trace to maintain a resonant point.

A system to control a linear compressor to generate a freezing force as a piston reciprocates according to rotation of a motor which receives power through a switch, comprising:

• means for detecting current and displacement of the motor when the linear compressor is driven;
• means for determining whether a center point of piston reciprocation is a resonant point based on the motor current and a phase difference of the motor displacement;
• and
• means for moving up or delaying a trigger signal corresponding to an absorption cycle or a compression cycle to be applied to the switch, if the center point of the piston reciprocation is not the resonant point.

A system to control a linear compressor as a piston reciprocates according to rotation of a motor which receives power through a switch, comprising:

• means for detecting a phase difference displacement magnitude;
• means for determining phase difference information corresponding to the phase difference displacement magnitude, and load information;
• and
• means for moving up or delaying a trigger signal corresponding to an absorption cycle or a compression cycle, such that the center point of the piston reaches a resonant point when a current and a phase difference of the motor deviate from predetermined ranges, wherein the moving up or delaying of the trigger signal is based on the phase difference information and the load information, such that the center point of the piston reciprocation can be controlled to coincide with the resonant point.