Analysis Of The Risk Area Of The Subsynchronous Resonance Of Wind Farm And The Torsional Vibration Fatigue Of Shafting

The distribution of wind resources in China is mostly away from the concentrated area of load.Large-scale long-distance transmission of wind power has become an important way to avoid resource waste and rationally allocate resources.In order to increase the long-distance transmission capacity of transmission lines,increase transmission efficiency and reduce transmission costs,the use of series capacitors and HVDC transmission methods in the process of power transmission is increasing.However,the use of series capacitance compensation technology and HVDC transmission technology may cause sub-synchronous resonance problems of wind turbines and affect the safe and stable operation of power systems.The influence of the change of wind farm size on the sub-synchronous resonance danger zone during large-scale wind power dispatching was analyzed.Taking the double-fed wind farm series compensation system as an example,the whole system of wind farm equivalent,for wind farm equivalent mathematical model of SSR analysis was established,using the method of equivalent resistance of the system to judge the stability of DFIG and grid,has made the change curve of the system the equivalent resistance of the scale of wind farm and different wind fanns the size of the system for dangerous area.The research results show that when the SSR is generated,the scale of different wind farms is not the same.Large-scale wind farms contribute to the stability of the system.Increasing the scale of wind farms helps to reduce the harm caused by sub-synchronous resonance.The above conclusions were simulated to verify the rationality of the results.Finally,the spectrum analysis is performed on the oscillated condition,in which the harmonic component is the corresponding sub-synchronous frequency.The stability of the sub-synchronous resonance torsional vibration interaction under external faults is deduced in detail.Subsequently,the equivalence methods for studying the SSR phenomena in wind farms are summarized,and the characteristics of various equivalent methods are compared and compared.Then,the TI fatigue identification procedure for triggering wind farms is described in detail.Finally,fatigue analysis of the same wind farm is performed by three different equivalent methods,and the final results are compared.