交直流混合微网变流器多模式协调控制策略
2017-10-09刘桂英桂永光粟时平明志勇邓宇恩
刘桂英,桂永光,粟时平,明志勇,张 捷,邓宇恩
(1.智能电网运行与控制湖南省重点实验室,长沙理工大学,长沙 410004;2.贵州电网公司铜仁供电局,铜仁 554300;3.国网江西省电力公司九江供电分公司,九江 332000)
交直流混合微网变流器多模式协调控制策略
刘桂英1,桂永光1,粟时平1,明志勇2,张 捷3,邓宇恩1
(1.智能电网运行与控制湖南省重点实验室,长沙理工大学,长沙 410004;2.贵州电网公司铜仁供电局,铜仁 554300;3.国网江西省电力公司九江供电分公司,九江 332000)
交直流混合微网含有不同类型的微源,分别建立了各个微源的并网接口控制模型。对双向变流器下垂控制曲线进行改进,当双向变流器变换功率很小时,其仍然处于停机模式,减少了电力电子器件不必要动作带来的谐波。在分析微源变流器不同运行模式的基础上,提出了一种基于直流母线电压与微网能量管理的协调运行控制策略。该控制策略综合考虑了直流母线的电压偏差、微网功率缺额、蓄电池的荷电状态等因素,能够实现交直流微网间的功率平衡,提高系统稳定性、可控性,适用于交直流微网的不同模式运行控制。仿真验证了所提控制策略的有效性和可行性。
混合微网;变流器;能量管理;协调控制
Abstract:Considering that the AC/DC hybrid micro-grid contains different types of micro-sources,grid-connected in⁃terface control models are established for each micro-source.The droop control curve is further modified for a bi-direc⁃tional converter,i.e.,when the conversion power of the converter is very small,it is still kept in a shutdown mode,which reduces the harmonics brought by the unnecessary action of power electronic devices.Based on the analysis of dif⁃ferent operation modes of micro-source converter,a coordination control strategy based on DC bus voltage and microgrid energy management is proposed.By considering factors such as DC bus voltage deviation,micro-grid power short⁃age and battery's state of charge,the proposed strategy can achieve the power balance in AC/DC micro-grid,and im⁃prove the stability and controllability of the system,which is suitable for different operation modes of AC/DC microgrid.The effectiveness and feasibility of the proposed strategy are verified by simulation results.
Key words:hybrid micro-grid;converter;energy management;coordination control
近些年来,鉴于能源短缺与环境污染等问题,可再生能源发电系统以分布式发电或者微网的形式接入低压配电网得到了广泛应用。由于常规的交流微网或者直流微网已经不能很好地适应日益发展的电力系统要求。……
