A device with a rotating element includes a housing body formed from a light alloy, wherein the housing body has a housing body thermal expansion coefficient, a bearing liner formed from a liner material disposed within the housing body, wherein the bearing liner has a bearing liner thermal expansion coefficient, and a bearing to support the rotating element with an outer race, wherein the bearing has a bearing thermal expansion coefficient, the outer race is press fit within the bearing liner, and the bearing liner thermal expansion coefficient is lower than the bearing thermal expansion coefficient.

A balancing method for balancing at high speed a flexible rotor of a rotary machine, the rotary machine having a stator, and the rotor being supported in the stator by at least two radial magnetic bearings. The balancing method including a step of placing the rotor inside the stator, a step of performing at least one first run in order to identify amplitude and angular location of the unbalance in a first speed range below critical speed, a step of placing first balancing masses inside the rotor on predefined first balancing planes, a step of performing at least one second run in order to identify amplitude and angular location of the unbalance in a second speed range above critical speed, and a step of placing second balancing masses inside the rotor on predefined second balancing planes.

A device with a rotating element includes a housing body formed from a light alloy, wherein the housing body has a housing body thermal expansion coefficient, a bearing liner formed from a liner material disposed within the housing body, wherein the bearing liner has a bearing liner thermal expansion coefficient, and a bearing to support the rotating element with an outer race, wherein the bearing has a bearing thermal expansion coefficient, the outer race is press fit within the bearing liner, and the bearing liner thermal expansion coefficient is lower than the bearing thermal expansion coefficient.

Apparatus, system and method for providing supplementary power. A vessel is configured to receive and contain hydraulic fluid, where the vessel includes a piston configured within the vessel to be vertically displaced by the hydraulic fluid and provide pressure from the weight of the piston to a fluid supply line. A solenoid valve is operatively coupled to the fluid supply line; and connected to a flywheel power supply that includes a flywheel and a hydraulic drive adapter, wherein the hydraulic drive adapter is operatively coupled to the solenoid valve via the fluid supply line. A signal is received indicating a power outage, where the solenoid valve is further configured to open in response to the signal and provide the hydraulic fluid pressurized by the piston to the hydraulic drive adapter and causes the flywheel to operate and provide the supplementary power.

Methods and systems for improved power generation are provided. In one embodiment, a flywheel is provided for use in a generator. The flywheel may include hollow disks that each contain a plurality of magnets that are angularly distributed around the hollow disks. The hollow disks may be fastened together using disk attachment brackets that attach to attachment points on the hollow disks. Stator disks, which may be separate from the flywheel, may be positioned between adjacent pairs of the hollow disks. The stator disks may contain multiple coils of wire that are angularly distributed around the stator disks. In operation, the flywheel may rotate while the stator disks remain stationary.