摘要
针对屋顶光伏发电系统接入低压配电馈线引起的配网电压不稳定问题,在满足低压馈线的电压波动机理的前提下,考虑配网线路容量和逆变器容量不变的特性,提出一种无功、有功、储能三者相结合的控制方法,以防止低压馈线电压失稳的现象发生。该策略首先利用光伏逆变器自身的剩余容量吸收无功功率,在一定程度上改善配网馈线的电压分布,然后运用有功控制得出每个光伏系统的功率输出。研究结果表明:在过电压情况下,可将多余功率通过光伏发电系统自身的蓄电池储能吸收,于高负载需求或夜间电压跌落时将储能释放,提高电网对新能源的消纳能力和新能源的输出功率;新型无功、有功、储能三者协同的功率优化方案不仅具有使馈线电压平衡的能力,而且具有更高的光伏利用效率,适用于未来大规模光伏接入配网的环境。
Considering that roof photovoltaic power generation system can lead to voltage instability in distributionnetwork, on the premise of voltage instability mechanism of low voltage feeder, invariant distribution line capacity andthe inverter capacity characteristics were considered, and then a reactive power, active power and energy storagecombined control method was proposed to prevent the occurrence of excessive voltage ripple’s phenomenon in lowvoltage feeder. Firstly, the strategy utilized the residual capacity of the photovoltaic inverter itself to absorp the reactivepower, which helped to improve feeder voltage distribution to a certain extent. Then the power output of each PV systemwas obtained by active power control. Under the condition of voltage limitation and the excess power could be absorbed by the battery energy storage of the photovoltaic power generation system, and the stored energy was released in highload demand or voltage drop at night. The results show that this method can improve the power grid of new energyconsumptive ability and enhance the new energy output power. The new power optimization scheme that reactive power,active power and energy storage cooperate not only has the ability of maintaining the low voltage feeder voltage within alimit, but also has higher PV efficiency and is suitable for future network environment of large-scale PV accessdistribution.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2017年第11期2973-2979,共7页
Journal of Central South University:Science and Technology
基金
国家自然科学基金资助项目(51307009)
湖南省教育厅创新平台开放基金资助项目(16K004)
衡阳市科技计划重点项目(2015KG27)
可再生能源电力技术湖南省重点实验室基金资助项目(2016ZNDL006)~~
关键词
光伏发电系统
电压平衡
无功控制
储能
PV system
voltage balance
reactive power control
energy storage
