Optimization For Pitch System Of Wind Turbine

In our country,as more support giving to the new energy, the installed capacity for wind turbines is increasing every year, with the annual growth rate about 30%. In order to reduce the overall cost of wind turbines, the size of the wind turbines is increasing. Due to the Upsizing of unit, it makes the pitch system more and more important. As the major component for absorbing wind energy and first brake equipment, the pitch system plays an important role in adjusting input power and pneumatically braking, which can make wind turbine operate reliably. However in actual operating, the malfunction happens most frequently in pitch system where the electronic component is using intensively. It can be seen from the operator’s statistical data that the pitch system has the highest malfunction rate in wind turbine, about 75% excepting the damage of other components, which can cause the downtime of wind turbine reaching 7000 hours per year. This index concerns whether the availability and power generation can reach the requirement of Contract. If the malfunction ratio of pitch system can reduce by 50%, it can recoup the losses of power generation and increase availability.The research object of this article is the pitch system of electrically pitch wind turbine which can be consisted of pitch controller, servo, position feedback sensor(encoder), backup supply and main supply. By a call on the database, it can be seen from the statistic data that the major damage components summed up to 70% of the total damage are pitch controller, position feedback sensor and backup supply. If the these components would be optimized reasonably, the downtime can reduce by 50%. For defects of the three components on the alarming failure in software or hardware, the test has been carried on specifically. Based on the result or data of the test, the three components are optimized. Through these optimizations, the expected goals are achieved and the effects are recognised by lab or scene verification.