The transmission of large scale wind turbines has traditionally been done mechanically but the development of larger turbines has been pushing this solution to its limits and the hydrostatic transmission is candidating its dominance. However, the hydrostatic transmission has its disadvantages in that traditional hydraulic pumps and motors are inefficient at small displacements and further development is therefore needed.

Digital Displacement Technology could be the improvement needed for feasibility and has been investigated by industry and academia alike. Studies have shown that a low pressure drop and fast switching valves are necessary for the success of this technology. This thesis investigates the modelling, optimisation, and design of such valve. The valve topology of interest is the variable reluctance or solenoid valve which history has proven reliable but suffering from a poor transient response compared to newer topologies. This disadvantage is sought minimised.

The study showed showed that in order to achieve the low pressure drop necessary the travel distance must also increase causing the switching time to increase thereby yielding an inefficient design.