Study On The Influence Of Guishan Wind Farm Connecting To The Zhuhai Power Grid

Wind power is one of the fastest developed renewable energy sources worldwide. InChina, the developable wind source offshore is triple of that onshore, and the offshore windpower can be connected directly to the coastal load centre, therefore offshore wind power willbecome an important component in Chinese electrical energy structure. Research works onthe influence of the offshore wind power connecting to local power system are urgent andimportant tasks.This thesis is focused on the influence of Guishan offshore wind farm to the Zhuhaipower system. In the first part of the paper, an outline of the Guishan wind farm is presented.Based on the load forecasting results, the analysis of district electric power balance is carriedout. It shows that the power grid of Zhuhai exists a big shortage of electricity under differentoperating modes and the electricity of the Guishan offshore wind farm can be consumedlocally..Secondly, electrical calculations are carried out applying the PSD-BPA. According to theload flow analysis, the stability analysis and the short-circuit calculation, we find that theinterconnection scheme for the Guishan wind power integration can meet the security andreliability requirements of the power system. In case of normal clearance of faults, the powergrid can maintain the transient stability. However, the load flow calculation shows that whenthe wind speed is high and one of the submarine cables is switched off in case of malfunctionor maintenance, the overload risk exists on the other cable. Thus the thesis suggests that thewind farms should consider the separating operation as its normal way of running in case ofhigh wind speed.For the interconnection of the offshore wind farm, its influence on the system voltagelevel is usually much higher than the influence on the system frequency and transient stability.A dynamic reactive compensator with the capacity of46MVar is suggested to be installed onthe PCC node of the Guishan offshore wind farm. According to the claims of The TechnicalSpecifications of the Connection of the Wind Power to the Power Grid (GB/Z19963-2011),this thesis analyzes the power quality near the PCC point from three aspects: the voltage deviation, the voltage flicker and the current harmonics.Study in this thesis will be helpful for the safe and stable operation of the Zhuhai powergrid and the successful connection of the offshore wind power. Furthermore, it could providereferences to the other coastal cities with offshore wind power interconnection in theGuangdong Province.