Self-contained pressure compensation system

A self-contained pressure compensation system, comprising:

• an oil supply device;
• a pressure compensation device and a power unit associated with the pressure compensation device, the pressure compensation device supplying oil to the power unit and detecting a change in a chamber pressure of the pressure compensation device itself in real time;
• and
• a switch control device for triggering the oil supply device to supply oil to the pressure compensation device if a chamber pressure detected by the pressure compensation device is less than a predetermined first threshold, and triggering the oil supply device to stop supplying oil to the pressure compensation device if the chamber pressure is greater than a predetermined second threshold;
• the pressure compensation device comprises:
• a displacement sensor fixed to an upper end of the pressure compensation device, for detecting a position of a piston relative to the upper end of the pressure compensation device, and for indicating to the switch control device that the chamber pressure is less than the predetermined first threshold if the position detected is less than a first predetermined value, and that the chamber pressure is greater than the predetermined second threshold if the position detected is greater than a second predetermined value;
• and
• the piston capable of moving up and down in a chamber of the pressure compensation device;
• the oil supply device comprises an oil storage tank, the oil storage tank being provided with an oil storage bladder, the oil storage bladder being connected to a first main oil passage;
• the switch control device is configured to switch on the first main oil passage when triggering the oil supply device to supply oil to the pressure compensation device, so as to supply oil to the oil storage bladder through the first main oil passage, causing a volume increase of the oil storage bladder and thus causing the oil in the oil storage tank to be squeezed by the oil storage bladder and enter the pressure compensation device through an oil passage between the oil storage tank and the pressure compensation device, so that the piston in the pressure compensation device moves downwards;
• and
• the switch control device is configured to switch off the first main oil passage when triggering the oil supply device to stop supplying oil to the pressure compensation device, so as to stop supplying the oil to the oil storage bladder.