高比例新能源电网新能源功率优化分配方法

New energy power optimal distribution method for high proportion new energy power grid

大规模新能源接入弱交流电网时易发生暂态过电压、锁相同步稳定等问题,为新能源充分利用带来挑战。对此,文中探究了新能源接入系统稳定水平的影响因素,将新能源短路比作为系统电压强度的量化评估依据,推导出短路比对新能源发电功率的灵敏度,综合考虑系统平均短路比和最低点短路比灵敏度,构建新能源短路比综合灵敏度指标,提出一种基于等综合灵敏度准则的新能源发电功率优化分配方法。利用该方法对新能源发电功率进行优化控制,在确保系统安全稳定的基础上充分利用可再生能源,最后以西北某新能源集中送出系统为算例进行分析,验证了该方法的可行性和有效性。

Large scale new energy access to weak alternating current(AC)power grid is prone to transient overvoltage,phase-locked synchronous stability and other problems,which bring problems for the full use of new energy.In this paper,the influencing factors of the stability level of the new energy access system are explored.The short-circuit ratio index of new energy is used as the quantitative evaluation basis of the system voltage intensity,and the sensitivity of the short-circuit ratio of new energy generation power is derived.The comprehensive sensitivity index of the short-circuit ratio of new energy is constructed by comprehensively considering the sensitivity of the average short-circuit ratio and the lowest short-circuit ratio of the system,and an optimal power allocation control scheme for new energy generation based on equal comprehensive sensitivity criterion is proposed.Based on this method,the optimal control of new energy power generation is carried out,and the full utilization of renewable energy is realized on the basis of ensuring the security and stability of the system.Finally,the feasibility and effectiveness of the proposed method are verified by taking a new energy centralized transmission system in Northwest China as an example.