Embodiments of systems and methods disclosed provide a hydraulic fracturing unit that includes a reciprocating plunger pump configured to pump a fracturing fluid and a powertrain configured to power the reciprocating plunger pump. The powertrain includes a prime mover and a drivetrain, the prime mover including a gas turbine engine. The hydraulic fracturing unit also includes auxiliary equipment configured to support operation of the hydraulic fracturing unit including the reciprocating plunger pump and the powertrain. A power system is configured to power the auxiliary equipment. The power system includes a power source and a power network. The power source is configured to generate power for the auxiliary equipment. The power network is coupled to the power source and the auxiliary equipment, and configured to deliver the power generated by the power source to the auxiliary equipment. Associated systems including a plurality of hydraulic fracturing units are also provided.

A powertrain component (21, 22, 23) for a wind turbine (100) is provided, comprising a powertrain component housing (20) with at least one rotating part (49) and a dry sump 5 lubrication system for lubricating the rotating part (49). The lubrication system comprises a dry sump lubricant tank (51, 52, 53) and a pump (60) for pumping the lubricant from the tank (51, 52, 53) towards a lubricant release point, the lubricant release point being provided at a level above at least part of the rotating part (49) for receiving the lubricant from the tank (51, 52, 53) and allowing the lubricant to lubricate the rotating part (49). 10 The tank (51, 52, 53) is integrated in or directly attached to the powertrain component housing (20) at a level below the at least one rotating part (49).

A powertrain component (21, 22, 23) for a wind turbine (100) is provided, comprising a powertrain component housing (20) with at least one rotating part (49) and a dry sump 5 lubrication system for lubricating the rotating part (49). The lubrication system comprises a dry sump lubricant tank (51, 52, 53) and a pump (60) for pumping the lubricant from the tank (51, 52, 53) towards a lubricant release point, the lubricant release point being provided at a level above at least part of the rotating part (49) for receiving the lubricant from the tank (51, 52, 53) and allowing the lubricant to lubricate the rotating part (49). 10 The tank (51, 52, 53) is integrated in or directly attached to the powertrain component housing (20) at a level below the at least one rotating part (49).

A method of operating a lubrication system for a gas turbine engine includes pumping a lubricant from a supply conduit to a bearing compartment. A pressure differential in the bearing compartment. The supply conduit is evacuated in response to the pressure differential creating step. The supply conduit is refilled with the lubricant from a reservoir conduit fluidly joined to the supply conduit at a junction by gravitationally draining the reservoir conduit.

A method of operating a lubrication system for a gas turbine engine includes pumping a lubricant from a supply conduit to a bearing compartment. A pressure differential in the bearing compartment. The supply conduit is evacuated in response to the pressure differential creating step. The supply conduit is refilled with the lubricant from a reservoir conduit fluidly joined to the supply conduit at a junction by gravitationally draining the reservoir conduit.

An oil circulation system of an internal combustion engine comprises a first oil pan and second oil pan, first oil supplied parts supplied with oil stored in the first oil pan, second oil supplied parts supplied with oil stored in the second oil pan, and a heating part. The heating part has oil paths through which oil flows and heats the oil flowing through the oil paths. The oil circulation system comprises a first circulation path circulating oil through the first oil pan, heating part, and first oil supplied parts, and a second circulation path circulating oil between the second oil pan and the second oil supplied parts.

An oil circulation system of an internal combustion engine comprises a first oil pan and second oil pan, first oil supplied parts supplied with oil stored in the first oil pan, second oil supplied parts supplied with oil stored in the second oil pan, and a heating part. The heating part has oil paths through which oil flows and heats the oil flowing through the oil paths. The oil circulation system comprises a first circulation path circulating oil through the first oil pan, heating part, and first oil supplied parts, and a second circulation path circulating oil between the second oil pan and the second oil supplied parts.

An electric drive for a transmission having a housing, a pump drive, and a primary sump configured to hold oil and operatively connected to a vehicle engine. The electric drive includes an oil-cooled electric generator electrically connected to an oil-cooled electric motor by an inverter. The electric generator includes a generator oil output operatively connected to and configured to deliver a flow of oil to a secondary sump located in the housing. The electric motor includes a motor oil output operatively connected to and configured to deliver a flow to the secondary sump. The secondary sump is separate from the primary sump, wherein the oil from the secondary sump is pumped back into the lubrication circuit of the transmission. The secondary sump includes a feature to allow overflow to drain to the primary sump.

Embodiments of systems and methods disclosed provide a hydraulic fracturing unit that includes a reciprocating plunger pump configured to pump a fracturing fluid and a powertrain configured to power the reciprocating plunger pump. The powertrain includes a prime mover and a drivetrain, the prime mover including a gas turbine engine. The hydraulic fracturing unit also includes auxiliary equipment configured to support operation of the hydraulic fracturing unit including the reciprocating plunger pump and the powertrain. A power system is configured to power the auxiliary equipment. The power system includes a power source and a power network. The power source is configured to generate power for the auxiliary equipment. The power network is coupled to the power source and the auxiliary equipment, and configured to deliver the power generated by the power source to the auxiliary equipment. Associated systems including a plurality of hydraulic fracturing units are also provided.

A fluid supply system supplying multiple fluid consumers of a vehicle with fluid, the fluid supply system including: a first pump supplying a first fluid consumer, arranged in a first supply circulation of the vehicle, with fluid; a second pump supplying a second fluid consumer, arranged in a second supply circulation of the vehicle, with fluid; and a directional control valve adjustable between a first valve position and at least one other, second valve position and preferably includes an electromagnetic device for adjusting. The directional control valve allows the fluid to be delivered from the second pump into the first supply circulation in the first valve position and separates the first supply circulation from the second pump, or allows the fluid to be delivered from the second pump into the first supply circulation only to a restricted extent as compared to the first valve position, in the second valve position.