Electronic load sensing (ELS) systems have long been expected to start replacing traditional (hydro-mechanical) load sensing (LS) systems, which today are the standard on most medium and high-end mobile hydraulic applications. The reason for this being the potentials that ELS brings relative to traditional LS-systems, in terms of better control and system utilization possibilities, combined with the increased acceptance and use of electronic sensors in mobile hydraulic machinery. The current work is to evaluate the suitability of an ELS concept applied to a Sauer Danfoss Series 45 H-frame open circuit axial piston pump. Emphasis is on performance robustness with respect to both variations in internal physical parameters of the pump as well as the type of application dependent load which the pump is expected to drive. The pressure control is established by means of cascade control utilizing four control loops with the outer being the pump pressure and then, in succession, the swash plate rotation, the spool position and the voice coil current. The proposed controller has been implemented experimentally and verified.

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