Research On Decision-making Methods For Large-scale Wind Power Integrated System Scheduling Based On Risk Theory

Deficiency of accommodation capacity has always been one of the primary problems in wind power development in China. And the existing scheduling methods for large-scale wind power integrated system are difficult to adapt its stochastic characteristic well. In this thesis the risk theory has been used to quantize the influence of integrated wind power on the safe and economic operation, based on which the risk analysis methods for multi-time scale active power scheduling were proposed. This thesis aimed at comprehensive coordinate the safe economic operation and wind power accommodation, maximizing the capability of wind power safe accommodation in scheduling optimization.Firstly, the theoretical foundation for risk analysis for large-scale wind power integrated system scheduling has been constructed. The characteristics of multi-time scale schedule system for large-scale wind power integrated system were analyzed and refined, based on which the research was focused on two key issues: the mid-long-term capability assessment for wind power accommodation and the short-term decision-making for wind power accommodation. And the risk quantitative indexes and relevant risk theories were proposed for the two key issues, risk assessment methods and probabilistic scheduling optimization theory were included.This thesis proposed a reasonable and effective mid-long-term capability assessment method for wind power accommodation to guide the scheduling and operation of large-scale wind power integrated system. The statistical analysis of daily peak-valley difference was conducted based on the influence mechanism of large-scale wind power on peak load regulation demand, which is the critical factor of wind power curtailment. And the mid-long-term probabilistic characteristics of daily peak load regulation demand were attained. And a mid-long-term risk assessment method was proposed for large-scale wind power integrated system based on the probability distribution model, which not only can avoid the complicated and uncertain data in calculation, but also can comprehensively measure the capability of wind power accommodation and the risk of wind power curtailment in mid-long-term scheduling and operation of power system.And the short-term decision-making of large-scale wind power integrated system scheduling must handle the confliction between the maximum of wind power accommodation and the safe and economic operation, especially highlighted in two aspects: optimal configuration of spinning reserve and coordination control of network security. For the two problems, the mathematical models for uncertainty in short-term scheduling were established, including the stochastic scenario model of wind power based on the Markov chain theory and the probabilistic outage model of transmission line based on the real-time power flow, based on which the risk decision-making models for economic dispatch and real-time scheduling were proposed using the probabilistic scheduling optimization theory. Those two probabilistic risk scheduling optimization model aimed at reduce the total risk value in the future schedule period. The planning of economic dispatch can comprehensive coordinate the economic running cost and security risk of power system and the planning of real-time scheduling can improve the security defense ability to risk caused by uncertainty, which can realize maximizing the wind power accommodation.