The present hydraulic variable-pitch mechanism of wind turbine uses three hydraulic cylinders to drive three crank and connecting rod mechanisms respectively; the blades are moved with the cranks. The hydraulic variable-pitch mechanism has complex structure, occupies a lot of space and its maintenance is trouble. In order to make up for the shortcomings of hydraulic cylinder variable-pitch syst...

sures experienced by a pipeline can be either beneficial or detrimental from an operational performance perspective, depending on the amount, the two phase regime of the mixture (whether homogeneous or slug) and the nature and cause of the transient. It is generally held that when free (undissolved) air, or gas, is present in a hydraulic system, it can greatly reduce the surge pressure levels b...

This study presents application of Dynamic Programming towards finding globally optimal control policies of a new, highly-efficient hydraulic elevator architecture. The architecture employs an actuator, three accumulators, and two hydraulic circuits bridged by a hydraulic transformer. An auxiliary electric motor exists only to compensate for system losses. Prior research identified a multitude ...

Recently, AIRBUS and ONERA were involved in the ESACS (Enhanced Safety Assessment for Complex Systems) European project. The aim of this project was to investigate new safety assessment techniques based on the use of formal design languages and associated tools. Two case-studies based on AIRBUS aircraft were used to validate the approach. Both a complete hydraulic system and an electric system ...

Preliminary note The aim of the investigation was to compare and unveil efficiency of electro-hydraulic control (EHR) system to mechanical three point hitch regulation in mouldboard ploughing. Increase of working velocity and three point hitch automatic regulation activity decreased depth of ploughing at both regulation systems but electro-hydraulic system done it more accurately since deviatio...