【Purposes】The new energy generation represented by wind power is the most realistic strategic choice to achieve the goals of carbon peaking and carbon neutrality. To absorb renewable energy electricity in power grid...【Purposes】The new energy generation represented by wind power is the most realistic strategic choice to achieve the goals of carbon peaking and carbon neutrality. To absorb renewable energy electricity in power grids, a new probabilistic evaluation method for available transmission capacity in transmission systems is proposed based on joint cumulants, and a decision model for risk available transmission capacity based on expected quantiles is proposed accordingly. As a vital component of available transmission capacity(ATC) calculation, the transmission reliability margin(TRM), as a reserved transmission capacity, reflects the impact of uncertainty factors on transmission capacity. However, in traditional calculation methods, TRM is determined through deterministic or probabilistic methods, which is difficult to reflect the risks brought by large-scale wind power consumption to ATC and cannot meet the requirements for transmission capacity risk management. 【Methods】Firstly, to address the issue that the cumulative method requires variables to be independent of each other and cannot consider the correlation of wind power output, a joint cumulative method combined with FGM Copula function is proposed to characterize the correlation of wind power output;Secondly, for the probabilistic assessment of available transmission capacity, a probabilistic assessment model for available transmission capacity is established by combining the partition integration method and the Comish Fisher expansion;Finally, in response to the problem that decision methods based on value at risk only consider the probability achieved at the tail of the probability distribution and cannot describe the risks generated throughout the distribution, a risk available transmission capacity index based on expected quantiles is proposed, and its evaluation process is proposed. 【Results】Verify the feasibility and practicality of the proposed indicators and models through case analysis.展开更多
针对传统灰狼优化(grey wolf optimization,GWO)算法在求解并网模式下微电网优化调度模型时存在种群分布不均以及易陷入局部最优等问题,对传统灰狼优化算法进行改进。首先,在传统灰狼优化算法基础上引入Tent混沌映射进行种群多样性初始...针对传统灰狼优化(grey wolf optimization,GWO)算法在求解并网模式下微电网优化调度模型时存在种群分布不均以及易陷入局部最优等问题,对传统灰狼优化算法进行改进。首先,在传统灰狼优化算法基础上引入Tent混沌映射进行种群多样性初始化,克服随机初始化导致的搜索空间覆盖不均的问题;其次,结合余弦函数在[0,π/2]的函数变化特点,提出基于余弦函数的非线性收敛因子调节策略,采用具有全局探索与局部开发能力的平衡算法提升寻优精度。针对储能系统频繁充放电导致寿命衰减的问题,通过量化储能系统频繁充放电造成的寿命损耗成本,建立计及光伏维护成本、电网交互成本及储能寿命损耗折算成本的经济优化调度模型。利用改进灰狼优化算法求解优化调度模型,并与其他优化算法进行对比,仿真结果表明:相较于传统定时充放电策略和常规能量分配方案,所提方法在晴天和阴天场景下均展现出更优的经济性,验证了所提的改进灰狼优化算法能够更好地实现并网模式下交流微电网灵活经济运行,为高比例可再生能源接入的微电网系统提供了兼顾经济性与实用性的优化调度新思路。展开更多
文摘【Purposes】The new energy generation represented by wind power is the most realistic strategic choice to achieve the goals of carbon peaking and carbon neutrality. To absorb renewable energy electricity in power grids, a new probabilistic evaluation method for available transmission capacity in transmission systems is proposed based on joint cumulants, and a decision model for risk available transmission capacity based on expected quantiles is proposed accordingly. As a vital component of available transmission capacity(ATC) calculation, the transmission reliability margin(TRM), as a reserved transmission capacity, reflects the impact of uncertainty factors on transmission capacity. However, in traditional calculation methods, TRM is determined through deterministic or probabilistic methods, which is difficult to reflect the risks brought by large-scale wind power consumption to ATC and cannot meet the requirements for transmission capacity risk management. 【Methods】Firstly, to address the issue that the cumulative method requires variables to be independent of each other and cannot consider the correlation of wind power output, a joint cumulative method combined with FGM Copula function is proposed to characterize the correlation of wind power output;Secondly, for the probabilistic assessment of available transmission capacity, a probabilistic assessment model for available transmission capacity is established by combining the partition integration method and the Comish Fisher expansion;Finally, in response to the problem that decision methods based on value at risk only consider the probability achieved at the tail of the probability distribution and cannot describe the risks generated throughout the distribution, a risk available transmission capacity index based on expected quantiles is proposed, and its evaluation process is proposed. 【Results】Verify the feasibility and practicality of the proposed indicators and models through case analysis.
文摘针对传统灰狼优化(grey wolf optimization,GWO)算法在求解并网模式下微电网优化调度模型时存在种群分布不均以及易陷入局部最优等问题,对传统灰狼优化算法进行改进。首先,在传统灰狼优化算法基础上引入Tent混沌映射进行种群多样性初始化,克服随机初始化导致的搜索空间覆盖不均的问题;其次,结合余弦函数在[0,π/2]的函数变化特点,提出基于余弦函数的非线性收敛因子调节策略,采用具有全局探索与局部开发能力的平衡算法提升寻优精度。针对储能系统频繁充放电导致寿命衰减的问题,通过量化储能系统频繁充放电造成的寿命损耗成本,建立计及光伏维护成本、电网交互成本及储能寿命损耗折算成本的经济优化调度模型。利用改进灰狼优化算法求解优化调度模型,并与其他优化算法进行对比,仿真结果表明:相较于传统定时充放电策略和常规能量分配方案,所提方法在晴天和阴天场景下均展现出更优的经济性,验证了所提的改进灰狼优化算法能够更好地实现并网模式下交流微电网灵活经济运行,为高比例可再生能源接入的微电网系统提供了兼顾经济性与实用性的优化调度新思路。
