Total Transfer Capability Calculation Of Power System Including Large-scale Wind Farms

While wind power generation is developing rapidly all through the world, there are more and more megawatt wind farms being connected directly into power system. In the traditional research, it is always focused on the influence of small-scale wind turbines on distribution system. But while large-scale wind platforms at sea is established, there are more and more large-scale wind farms, whose total installed capacity is more than 10MW. In other words, in the near future, there are more and more large-scale wind farms being connected directly into power system. Therefore, the research of this connection is getting more attention.Meanwhile, in a new competitive environment, Available Transfer Capability (ATC) is a very important parameter for independent system operator (ISO) and all companies to participate in power transaction activities. The calculation of Total Transfer Capability (TTC) is the groundwork of ATC research. Therefore, a new methodology to evaluate TTC of power system, which contains large-scale wind farms, considering static voltage stability constraints is developed in this thesis and the following work are completed.Firstly, the exploitation of wind energy and history of wind power generation is introduced and the detail of this technology is presented in four aspects: styles of wind turbines (WT), basic characteristics of WT, power regulation of WT and the influence of connecting power system with WT.Secondly, to ameliorate the deficiency of traditional power flow arithmetic containing the static modle of WT, the uniformly iterative power flow calculation model and continuation power flow (CPF) calculation model of power system containing asynchronous wind power generators is established, by deducing integratedπ-type equivalent circuit of asynchronous generators. The feasibility of this new model is illustrated by an application to an IEEE RTS-118 system containing wind farms. By comparing with traditional PQ model and RX model, it is proved that this new method enhances the speed of constringency in precondition of guaranteeing the precision of calculation.Then, based on this presented uniformly iterative CPF calculation model containing asynchronous wind power generators, TTC of power system, which contains wind farms, considering static voltage stability constraints is calculated and analyzed. Moreover, the infection of wind speed, wind power penetration and wind turbine compensation capacity on TTC is investigated. It is indicated that, when calculating the ATC of power system containing large-scale wind farms, the operator should considering the influence of diversification of future wind speed, collocation of wind turbine compensation capacity and variation of wind power penetration on ATC.