Research On Wind Power Integration Capacity Assessment Method In Power System

Wind power is different from conventional power unit,which is random fluctuation, with the percentage of wind power increasing.It has growing impact on the stable operation of the power grid, which reflected on the following two aspects: on the one hand, there is an inverse relationship between wind power and peak load, which brings new challenges to conventional units. on the other hand, wind farm is always located in the peripheral of network and far away from the load center, and this increases power grid transmission pressure. Wind power fluctuation may lead to off-grid of a large area of wind farms, as well. It endangers the safety of the system.At present, the calculation methods of wind power capacity penetration into power grid can be divided into two aspects. Firstly, from the long-term perspective, the influent factors include the power of conventional unit adjustment ability, pumped storage power station and tie line plan are influent on wind power capacity of grid system. Secondly, from short-term view, to calculate wind power capacity that can be accepted by the power grid should consider one or several of system safety operation indicators, such as node voltage constraints and branch power constraint, unit operation constraints and spinning reserve system constraints, etc.Therefore, this paper studies wind power capacity penetration into power grid assessment methods from the long-term and short-term perspective respectively. From the view of long-term planning, while calculating wind power integration capacity, the regulating peak ability constraint, transmission section constraints are considered; From the view point of operation, while establishing mathematical model of wind power integration capacity, the static voltage stability margin are considered, and the Jacobin matrix minimum model sign value is introduced into power grid wind power capacity calculation model as a constraint. It can quantify the wind power integration capacity influence on the system static voltage stability margin.Studying on the wind power capacity that can be accepted by the power grid from aspects of planning and operation are important. Firstly, the capacity of wind power can guide long-term power supply, power grid planning and capital, as well as the resources optimization; secondly, from the view of system operation, to learn the capacity of wind power that the system with the current structure and operation conditions can accept is very significant.