Research On Primary Frequency Control Strategy Of Wind Turbine Considering Load Of Key Parts

With the rapid development of new energy sources,the frequency modulation capability of traditional thermal power units alone cannot fully meet the needs of maintaining grid frequency stability.New energy units such as wind turbines must be equipped with similar frequency response characteristics and frequency control capabilities of thermal power units.In order to achieve maximum wind energy capture,wind turbines no longer have a coupling relationship between generator speed and grid frequency,which also makes wind turbines unable to respond to grid frequency changes,thus losing the inertial response and primary frequency modulation capability of conventional generator sets.Therefore,researching wind turbines to participate in primary frequency control has become an inevitable requirement for promoting the development of the wind power industry.At the same time,the calculation of unit load is an important part of wind turbine design.The load is the basis for the strength check of the wind turbine and one of the important criteria for evaluating the control strategy.It is directly related to the safety and reliability of the production and operation of the unit.Changes in control strategies can have a significant impact on the operating load of a wind turbine.A frequency modulation control strategy will cause the generator speed and torque to fluctuate drastically,causing rapid changes in wind turbine load and severe downtime.Therefore,this paper considers the load of key parts of wind turbines to study the primary frequency control strategy.First,this paper analyzes the source,type,influencing factors and calculation principles of the load on wind turbines,and on this basis,puts forward the basic method of wind turbine load calculation.Secondly,based on GH Bladed,a 2MW double-fed wind turbine generator is simulated and analyzed,and the active power control principle of wind turbine is analyzed.The focus is on the maximum power tracking phase torque control below rated power and the constant power phase pitch control.With optimization,the simulation results show that the optimal control strategy can effectively track and limit the active power.Then,aiming at the analysis of the existing primary frequency modulation control method,a primary frequency modulation control strategy based on rotor inertia control is introduced.Finally,quantitative analysis of the impact of control strategy changes on the load of key parts of wind turbines provides a basis for further optimization of the primary frequency control strategy and analysis of wind turbine load.