Regeneration circuit for hydraulic motor, construction machine including regeneration circuit, and method of controlling regeneration circuit

A method of controlling a regeneration circuit, the method comprising:

• collecting return oil via an oil collection passage of the regeneration circuit from a hydraulic motor to which pressure oil discharged from a hydraulic pump is supplied;
• recovering energy from the collected return oil;
• and
• resupplying pressure oil via an oil resupply passage of the regeneration circuit to the hydraulic motor,
• wherein in the recovering, pressure energy of the collected return oil is converted into mechanical energy by a regeneration system of the regeneration circuit, and the mechanical energy is accumulated;
• and
• wherein in the resupplying, low pressure oil with a pressure lower than a pressure of the collected return oil is resupplied by the regeneration system via the oil resupply passage to the hydraulic motor when the pressure energy of the collected return oil is converted into the mechanical energy.