Hydraulic Control Technology for Wind Power Pitch Control Hydraulic cylinders precisely controlled by open and closed-loop control systems The availability of wind and grid capacity are the decisive factors for the wind turbine’s operational state—with Rexroth proportional hydraulic valves for flexible adaptation. In normal operation the positioning motions can be executed sensitively and slowly to minimize stressing of the materials, while in extreme conditions they are performed suitably quickly to prevent damage to the turbine. Hydraulic cylinders accurately set rotor blade pitch. Cylinder performance depends on the seal system. The standard seal system is pressure-loaded with pressure-dependent friction; the high-performance seal system operates pressure-unloaded with pressure-independent friction. Rexroth cylinders are available with either system, depending on the customer’s specific needs. Proportional valves in numerous possible variants control the cyliinder: Valves with external electronics, integrated electronics, or integrated electronics and position controller Command value selection via a current interface, voltage interface, or field bus Valve characteristic curves linear, progressive, or customized Control block drive As the central drive element, the control block unites all the components in a single subassembly. As a result of its dual function as a component carrier and connecting element, the entire drive has been given an especially compact design. In addition to savings of space and materials, it also provides protection from environmental aggression and physical damage. The compact cartridge valves employed in the central block control secondary functions, including passive position holding, counterbalancing, and emergency stopping. The interaction of electrically and hydraulically operated seat valves significantly reduces the number of control signals and system-related internal leakage. Learn more about Gear Technology and Hydraulics for Wind Turbines developed by Bosch Rexroth for he wind energy industry. Back to Hydraulic Control Systems