Power sources and transmission networks for auxiliary equipment onboard hydraulic fracturing units and associated methods

A system for fracturing a well, comprising:

• a plurality of mobile hydraulic fracturing units, each hydraulic fracturing unit comprising:
• a chassis;
• a reciprocating pump configured to pump a fracturing fluid from a blender to a well through a manifold;
• a powertrain mounted to the chassis and configured to drive the reciprocating pump, the powertrain comprising a prime mover and a drivetrain;
• and
• auxiliary equipment onboard the chassis configured to support operation of the reciprocating pump and the powertrain;
• at least one auxiliary-equipment power network distinct from the drivetrain and configured to deliver operating power to the auxiliary equipment of at least two of the plurality of hydraulic fracturing units;
• and
• at least one auxiliary-equipment power source configured to supply power to the auxiliary-equipment power network independently of power delivered by the powertrain to the reciprocating pump.

A hydraulic fracturing unit, comprising:

• a mobile chassis;
• a reciprocating plunger pump configured to pump a fracturing fluid at high pressure;
• a powertrain comprising a prime mover and a drivetrain mechanically coupled to the reciprocating plunger pump;
• auxiliary equipment onboard the chassis configured to support operation of the reciprocating plunger pump and the powertrain;
• and
• an onboard auxiliary-equipment power arrangement comprising:
• an auxiliary-equipment power source configured to generate power independently of power provided by the powertrain to the reciprocating plunger pump;
• and
• an auxiliary-equipment power network configured to distribute power from the auxiliary-equipment power source to the auxiliary equipment.

A method of fracturing a well, comprising:

• arranging a plurality of hydraulic fracturing units at a well site, each comprising a reciprocating pump driven by a powertrain and auxiliary equipment onboard a chassis;
• connecting an auxiliary-equipment power network to auxiliary equipment onboard at least two of the plurality of hydraulic fracturing units;
• operating an auxiliary-equipment power source to supply power over the auxiliary-equipment power network independently of power delivered by the powertrains to the reciprocating pumps;
• and
• pumping fracturing fluid to the well using the reciprocating pumps while powering the auxiliary equipment via the auxiliary-equipment power network.