System and methods for cooling electronic equipment

A system for cooling electronic equipment, comprising:

• a free-cooling system configured to cool a first fluid in thermal communication with electronic equipment using atmospheric air, the free-cooling system comprising:
• a free-cooling device configured to cool a second fluid using atmospheric air;
• and
• a main heat exchanger in fluid communication with the free-cooling device, the main heat exchanger configured to enable heat transfer from the first fluid to the second fluid;
• and
• a mechanical sub-cooling system coupled to the free-cooling system, the mechanical sub-cooling system configured to cool a second fluid flowing in the free-cooling system as a function of an amount by which the free-cooling system has exceeded a predetermined cooling capacity, the mechanical sub-cooling system comprising:
• a first heat exchanger that enables heat transfer from the second fluid flowing into the main heat exchanger to a third fluid flowing through the first heat exchanger;
• a compressor subassembly comprising:
• a compressor in fluid communication with the first heat exchanger and configured to compress the third fluid flowing out of the first heat exchanger;
• a motor that drives the compressor;
• and
• a variable frequency drive that drives the motor;
• and
• a second heat exchanger in fluid communication with the compressor and enables heat transfer from the compressed third fluid to the second fluid flowing out of the main heat exchanger;
• and
• a variable frequency drive cooling system configured to cool the variable frequency drive using at least a portion of the first fluid flowing out of the main heat exchanger.

A method of assembling a system for cooling electronic equipment, the method comprising:

• coupling a first fluid circuit that is in thermal communication with electronic equipment to a first fluid path through a first heat exchanger;
• coupling a second fluid circuit that is in thermal communication with atmospheric air to a second fluid path through the first heat exchanger to enable heat transfer from the first fluid circuit to the second fluid circuit;
• coupling a first fluid path through a second heat exchanger to an output of the second fluid path through the first heat exchanger;
• coupling a first fluid path through a third heat exchanger to an input of the first fluid path through the first heat exchanger;
• coupling in series a second fluid path through the second heat exchanger to a second fluid path through the third heat exchanger;
• coupling a compressor in the second fluid path through the third heat exchanger to the second fluid path through the second heat exchanger to form a third fluid circuit;
• and
• coupling a heat exchanger of an inverter of a variable frequency drive configured to drive the compressor to the first fluid circuit to cool the heat exchanger of the inverter via the first fluid circuit.

A system for cooling a variable frequency drive for driving a compressor of a cooling system for electronic equipment, the system comprising:

• a first fluid circuit that is in thermal communication with electronic equipment, coupled to a first fluid path through a first heat exchanger;
• a second fluid circuit that is in thermal communication with atmospheric air coupled to a second fluid path through the first heat exchanger to enable heat transfer from the first fluid circuit to the second fluid circuit;
• a first fluid path through a second heat exchanger coupled to an output of the second fluid path through the first heat exchanger;
• a first fluid path through a third heat exchanger coupled to an input of the first fluid path through the first heat exchanger;
• a second fluid path through the second heat exchanger coupled in series to a second fluid path through the third heat exchanger;
• a compressor in the second fluid path through the third heat exchanger coupled to the second fluid path through the second heat exchanger to form a third fluid circuit;
• and
• a heat exchanger of an inverter of a variable frequency drive configured to drive the compressor, the heat exchanger of the inverter coupled to the first fluid circuit to cool the heat exchanger of the inverter via the first fluid circuit.

A method of cooling electronic equipment, comprising:

• cooling electronic equipment using a first fluid;
• free cooling the first fluid by enabling heat transfer from the first fluid to a second fluid that has been cooled using atmospheric air;
• and
• mechanically cooling the second fluid,
• wherein mechanically cooling the second fluid includes:
• cooling the second fluid before using the second fluid to free cool the first fluid by enabling heat transfer from the second fluid to a third fluid;
• compressing the third fluid using a compressor including a variable frequency drive, the compressor being configured to cool an inverter of the variable frequency drive;
• condensing the compressed third fluid by enabling heat transfer from the compressed third fluid to the second fluid after using the second fluid to free cool the first fluid;
• reducing a pressure of the condensed third fluid to reduce a temperature of the third fluid;
• and
• diverting at least a portion of the first fluid to enable heat transfer from the inverter of the variable frequency drive to the first fluid.

A method of cooling data center equipment, the method comprising:

• cooling electronic equipment using a first fluid;
• free cooling a second fluid that is in thermal communication with the first fluid;
• mechanically cooling the second fluid using a third fluid as function of a wet bulb temperature;
• diverting a portion of the first fluid flowing to the electronic equipment to cool an inverter of a variable frequency drive for driving a compressor for compressing the third fluid;
• and
• returning the portion of the first fluid cooling the inverter of the variable frequency drive to the first fluid flowing from the electronic equipment.