Hydraulic system is an application of fluid properties within an engine in relation to the tendency of fluids when exposed to pressure. Fluids have the property of exerting pressure equally to all directions in their containers. This property is often employed in mechanics to lift heavier loads with application of little effort. The property of fluidsto exert equal pressure in all directions has been used in manufacturing of different machines in various fields. However, due to movement of different parts of machines, their components must be modeled to endure high strain and wear to increase their efficiency. This paper focuses on the hydraulic pitch system of a Wind turbine machine and seeks to explain their overall functions and operations. It also narrows to the advantages and inner working of a pump while explaining the role of pumps in a hydraulic system.
Hydraulic Pitch System of a Wind Turbine
A wind turbine is used to harness electric power from wind energy. Hydraulic pitch system helps in tapping of wind energy as it allows the turbines to shift automatically with an increase in wind velocity. Hydraulic pitch system in wind turbines is composed of valves which are proportioned to control the hydraulic actuators. The axial piston pumps in the system provide the needed pressure for operations in hydraulic system. The bladder-type accumulators in hydraulic system store needed energy for emergency operations and enable the system operations to be reliable even at very adverse conditions of low temperatures.
The hydraulic control block is very essential as it helps in the drive of the hydraulic system. These basic and core parts of hydraulic system help in measuring the velocity of wind. The response from the valves and the accumulators is measured in milliseconds. Hydraulic components offer the required standard monitoring of machines for their maximum output. Components such as sensors, pressure transmitters and filter monitors help in easy motoring of wind turbines.
Hydraulic Gear Pumps (External Gear)
Hydraulic gear pumps are mainly composed of two gears; idler and driven gears. Since a gear pump is a positive displacement pump, it pumps oil in any turning of the pump. The pressure between the teeth results into equal push to different opposite directions hence the torque remains unaffected and oil carried to the outlet. As the gears rotate suction is created and oil is sucked by the inlet port of the pump resulting into the operation of the system.
The hydraulic gear pumps are very cheap to manufacture, thus, minimal costs incurred for their replacement. They are compact and easy to use in their operations, thus, are preferred compared to other types of gear pumps. The operation of the pump occurs when the engine runs the pump rotating group causing the piston to move over the swash plate which is usually located in a neutral position. Further movement of control pedal results into inclination of the swash plate and, thus, the pump pushes oil through the gears.
The mechanics of hydraulic system have been adopted inmanufacturing machines. Fluids have been used in engines manufacturing with credible results. Some of these machines include wind turbines which have adopted hydraulic pitch system in their operations and, thereby, achieving high levels of efficiency. Hydraulic pitch systems have been enhanced by the application of gear pumps.