采用虚拟电抗的孤立微网负荷按比例分担控制方法  

Control Strategy of Sharing Power in Proportion for Autonomous Microgrid by Virtual Inductance

作　　者：程军照 王文玺 陈江波[2] 

机构地区：[1]云南电网有限责任公司电网规划研究中心,昆明650011 [2]中国电力科学研究院,武汉430074

出　　处：《高电压技术》2016年第7期2142-2148,共7页High Voltage Engineering

基　　金：国家自然科学基金青年基金(51307154)~~

摘　　要：有功功率–频率(P-f)、无功功率–电压(Q-U)下垂控制在微网逆变器中得到广泛应用,但它无法同时实现不等容逆变器之间P和Q的按比例分担,可能会导致逆变器之间的巨大功率环流,即使和虚拟阻抗相结合也无法解决这一问题。为此,从理论上分析了上述问题的根本原因,并提出了一种新的负荷按比例分担控制方法,保留传统的P-f下垂、舍弃Q-U下垂并同时加入虚拟电抗,按照逆变器额定容量的反比选择虚拟电抗的大小,并分析了采用该方法后微网的稳定性问题。研究结果表明:该方法能在逆变器之间无通信的前提下以较高准确度同时实现不等容逆变器之间P和Q的按比例分担,Matlab仿真验证了该方法的有效性。Active power-frequency（P-J） and reactive power-voltage（Q-U） droop control is widely used in microgrid. But it is unable to simultaneously share the accurate active power and reactive power for inverters with different ratings, which may result in great circulating power among inverters and cannot be solved by combining P-f Q-U droop control and virtual impedance. We investigate the troubles occurred in power sharing for conventional droop control and propose a novel control method. In the proposed method, conventional P-f droop is reserved and Q-U droop is abandoned while virtual reactance is introduced, which are selected in reverse proportion to inverters＇ ratings. Stability analysis is also carried out for microgrid to which the proposed method is applied. The proposed method can simultaneously achieve active power and reactive power sharing in proportion to inverters＇ ratings in the absence of communication among inverters, which is confirmed by Matlab simulation. Key words： microgrid; inverter; parallel operation; droop control; virtual inductance

关 键 词：微网 逆变器 并联运行 下垂控制 虚拟电抗 

分 类 号：TM464[电气工程—电器]