Compact electro-hydraulic drives in the fractional horsepower range have a high potential for various applications, such as hand devices for extreme operation forces, for mobile robots, or for auxiliary drives of production machines. These drives should feature high power density, good energy efficiency, and easy control. The core component of such drives is the electro-hydraulic transducer. Motor pump concepts proven for high rated power lose their excellent performance efficiency and power density characteristics in the low power range. The oscillation pump avoids the responsible elements and loss sources of the conventional hydraulic pumps. With high oscillation frequencies high power density and efficiencies can be achieved.
This thesis demonstrates this for a rated power of several hundred watts with hitherto unrivalled efficiencies and power densities. On the pump side the main ingredient are very fast check valves, on the electrical side a powerful electromagnetic linear actuator. The system is operated at resonance to realize the high acceleration forces of the mover by mechanical springs. The fast check valves and the electromagnetic actuator as core elements are extensively investigated. Important new insights in the relevant flow and motion processes of the check valve are obtained from which dimensioning and design guidelines are derived.