摘要
主动配电网环境下,将发电具有间歇性和随机性特点的小风电、光伏发电与蓄电池组成微电网,协调控制其内的多个可再生发电单元使其成为发电功率分时恒定的发电单元或者负荷,既方便配电网对微电网群的调度和管理,又能促进分布式可再生能源的安全消纳。在综合考虑风光储微电网风速曲线和光照条件瞬时变化且储能容量配置较小等实际情况下,提出一种分层协调控制策略。首先根据每时段风速及光照强度预测信息给出了联络线分时交换功率的计算方法,上层中心控制器将该联络线交换功率参考值与上级主动配电网调度中心通信,制定分时联络线交换功率。上层中心控制器并依据此分时功率需求实现系统运行模式的选择及切换以及底层控制器的选择和管理。该分层控制策略实现了运行状态的无缝转换,保证了风光储微电网按照联络线交换功率需求输出,即联络线功率分时恒定。当微电网内风电和光伏输出的瞬时功率之和与联络线交换功率需求相差较大时,微电网内可能会出现部分弃风弃光。该文建立了风光储微电网仿真系统,仿真结果验证了所提策略的正确性与有效性。
In an active distribution network environment,the intermittent and random renewable generation units,such as small wind generation,photovoltaic( PV),and energy storage unit,e. g. battery,can be combined to form a microgrid( MG). The microgrid can be controlled as a generator or a load with a timed constant power flow by coordinating the power output of its multiple renewable generation units. This way is helpful for the active distribution network to dispatch and manage the microgrid group and to promote the penetration of distributed renewable energy sources. A hierarchical coordination control strategy is employed by considering the change of wind speed and solar radiation intensity as well as the limited storage capacity. A method to calculate the expected interchange power plow of the microgrid tie-lineaccording to predicted wind speed and solar radiation intensity in each time period is presented. A central controller is designed to formulate the plan of microgrid tie-line interchange power plow with the dispatch center of the active distribution network by communicating with upper active distribution grid center. The central controller can also select the correct operation modes and achieve the smooth switch between different operation modes,to select and manage the local controllers. The hierarchical control strategy realizes the seamless transformation of the running state,and ensures the output power flow of the microgrid to follow the demand of the tie-line interchange power. When the difference between the sum of output instantaneous power of wind generation,PV in the microgrid and tie-line interchange power plow is big,the microgrid may partly abandon the generation active power of wind and PV powergeneration. A simulation model of wind/PV/battery microgrid is established and the simulation results confirm the effectiveness of the proposed control strategy.
出处
《电工技术学报》
EI
CSCD
北大核心
2017年第15期169-179,共11页
Transactions of China Electrotechnical Society
基金
国家自然科学基金(51577124)
天津市重点基金(15JCZDJC32100)
天津市科技支撑计划重点项目(15JCZDJC32100)资助
关键词
风光储微电网
联络线功率分时恒定
分层协调控制
中心控制器
底层控制器
Wind/PV/battery microgrid
timed constant power flow of microgrid tie-line
hierarchical coordination control
center controller
local controller
