Research On Multi-step High-order Taylor Series Method For Transient Stability Calculation Of Power System Integrated With Large Scale Wind Farm

Wind power generation is the most rapidly developing and mature technologyamong all the clean and renewable energy power generation. Wind power generationin China entered in a fast developing period in2005and by the end of2011, totalinstalled capacity of China’s wind power reached62700MW, ranking the first in theworld. With the constant increasement of wind generation capacity, the impactcaused by the integrated wind farm to the security and stability of power systemshouldn’t be ignored anymore.Direct-drive permanent magnet synchronous generator（DDPMG）is called thethird generation of wind turbine and have a very bright future，yet there is few studyof the transient stability calculation of power system integrated with DDPMG-basedwind farm. Hence，this paper studies the transient stability calculation of powersystem integrated with large scale DDPMG-based wind farm by using the multi-stephigh-order Taylor series method.In this paper the transient model of DPMSG isestablished and the transient stability calculation of power system integrated withlarge scale wind farm is perform on the software of Power System Analysis Toolbox（PSAT）and solved by multi-step high-order Taylor series method.Multi-step and high-order integration method, a fast and effective method fortransient stability calculation, has the advantages of high-accuracy and large-step,and can make full use of the information contained in higher derivatives of severalsteps to improve the accuracy order of the algorithm. But as no guideline fordetermining optimal integration scheme is put forward when the algorithm wasfirstly proposed, the excellent properties of multi-step and high-order integrationmethod can not be exerted to utmost.Based on the study of calculation amount andconvergence and stability properties of multi-step high-order Taylor series methodfor transient stability calculation, the guidelines for determining optimal integrationscheme of the method are put forward and a specific multi-step high-order Taylorseries method with practical value is obtained. This paper shows how to use theproposed guidelines through a specific example and also verifies the improvementsin stability and speed of the optimal method.In order to fully study the transient stability of power system integrated withDDPMG-based wind farm, the transient model of DDPMG is established, includingwind turbine dynamic model, permanent magnet generator model, back-to-backconverter model and generator controller model. A complete DDPMG-based windpower system transient simulation model is given.Based on the transient model of DDPMG, the wiring diagram of IEEE14-node simulation system integrated with DDPMG-based wind farm is established on thesoftware of Power System Analysis Toolbox（PSAT）and the transient stabilitycalculation of the simulation system is solved by multi-step high-order Taylor seriesmethod. The transient stability of power system caused by the variations of windspeed and by big disturbance in the network are mainly discussed. Changes of powerangle, rotating speed and voltage amplitude of the two cases are all showed anddiscussed. The work of this paper provides reference to further research on thetransient stability calculation of power system integrated with DDPMG-based windfarm.