储能与间歇式DG的容量配比关系以及实用估算方法

随着分布式电源在配电网中渗透率逐步提高,其间歇性和波动性等特点给电网带来了一定的冲击。储能是解决间歇式分布式电源DG接入问题的关键,现有的研究尚未明确储能与DG的容量配比关系。基于DG频谱分析结果对平滑输出场景下储能DG容量配比问题展开了研究,并提出了一种实用的储能容量配置估算方法。首先,介绍了储能容量优化的原理和算法。其次,利用某地各项目的实际间歇式DG数据,使用频谱分析的方法得到容量优化结果,并分析得到DG最大波动值与最优储能功率容量的关系、储能功率容量与能量容量的关系。实际工程较易得到的为DG的额定功率,因此还补充分析了DG额定功率与最大波动值之间的关系,最终得到储能容量与DG额定功率之间的关系,即储能与DG的配比规律。据此可无需要储能优化算法而通过简单手工计算得到近似优化的储能功率容量和能量容量。最后,通过算例对比了储能容量优化算法和实用方法,结果表明该实用方法简单有效。

Ratio Between Energy Storage and Intermittent DG Capacity with a Practical Storage Capacity Estimation Method

As the increasing development of DG penetration in distribution network, the impact brought by DG’s characteristics of intermittency and volatility is more obvious. Energy storage system(ESS) is the key solution to this problem. However, the ratio of energy storage and DG capacity is not very clear in current research. An estimation method is proposed based on spectral analysis. Firstly, the calculation approach of ESS capacity based on filtering is introduced. Secondly, based on experiment data, the relationships of the biggest fluctuation and ESS rated power, the ESS rated power and ESS rated energy capacity are analyzed. Because of the difficulty in real project, DG rated power is used to calculate the biggest fluctuation power. Hence the ratio of DG rated power and ESS capacity can be obtained by easy calculation instead of complex energy storage optimization method. In the end, the comparison of results obtained from ESS capacity optimization and proposed practical method on typical engineering cases proves simplicity and effectiveness of proposed method.