Risk assessment method for wind power grid-connected system based on wind speed time period characteristics

Abstract

The invention discloses a wind-power grid-connected system risk assessment method based on the wind speed time period feature. The method comprises the following steps: processing the traditional annual wind speed probability distribution as the time-varying distribution function with time-dependent wind speed, reflecting the main change rule of the wind speed by using a time period fitting function, and reflecting the fluctuant feature of the wind speed by using the random variable obeying some probability distribution, wherein the time period fitting function and the wind speed random variable are overlapped to obtain a time period feature model of the wind speed; computing the time-varying capacity of a wind power plant through a function relation between the time-varying wind speed and the wind generation set, and assessing the time-varying risk index of the wind-power grid-connected system by using the Monte Carlo sampling method. By using the method disclosed by the invention, the time-dependent system risk index can be computed, and the auxiliary information can be provided for the power grid planning and designing, the system scheduling and operation-maintenance decision-making; and the method is in favor of managing and controlling the power grid running risk, and improving the reliability level for the power system running.

Description

technical field [0001] The invention relates to the technical field of risk assessment of power generation and transmission systems, in particular to a risk assessment method for wind power grid-connected systems based on wind speed time period characteristics. Background technique [0002] Since my country promulgated the "Renewable Energy Development and Utilization Promotion Law" in 2005, wind energy and other renewable energy sources have begun to develop rapidly with the support of national policies. In recent years, more and more large-scale wind farms have been connected to the power grid. However, due to the random and intermittent characteristics of wind power generation itself, it has a greater impact on the reliability of power system operation. [0003] Since the development of wind power, many scholars have conducted research on the risk assessment of power systems under the integration of large-scale wind power. To establish a reliability model of a wind farm,...

AI Technical Summary

Problems solved by technology

Therefore, the traditional system risk assessment method using Weibull distribution to generate wind speed samples cannot fully reflect the actual situation, and may cause system operators to misjudge the system risk, such as underestimating the system reliability in the month with high wind speed. Maintenance will lead to a large number of curtailed wind; overestimating the reliability of the system in months with low wind speeds, not reserving enough backup power generation capacity, resulting in insufficient power supply and resulting in power outages

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