Background: This invention combines rotating kinetic and pneumatic energy storage into a single device to drastically increase the energy storage density over traditional hydraulic accumulators. Technology Description: Energy is stored in the device by either compressing a gas with the addition of hydraulic fluid or by applying a torque to the device. The two energy domains are coupled as the hydraulic fluid changes the moment of inertia of the device. Due to the pressure gradient created by the centripetal acceleration of the hydraulic fluid the hydraulic system pressure can be directly controlled independently of the quantity of energy stored. This feature allows the hydraulic system pressure to remain constant regardless of the state of charge. Applications: Hydraulic systems
Hydraulic system pressure can be directly controlled independently of the quantity of energy stored.