摘要
直流配电网直接面向直流供用电设备,便于实现可再生能源的并网集成和直流负荷的高效用电,具有重要的应用前景。在直流配电网中,为了平抑由可再生能源引起的节点电压波动,该文提出直流电气弹簧的概念。利用电力电子变换器调节直流配电网中的可控负荷,使其跟随可再生能源出力的波动性和不确定性,实现对波动功率的就地平衡,避免间歇性潮流在配电线路上的传输,从而有效抑制直流配电网的电压波动。针对一个典型的直流配电网,在建立物理模型和电路模型的基础上,利用数学模型分析了电压波动问题的成因及其影响因素;然后提出了直流电气弹簧的数学模型、参数设计、控制策略和有效边界条件,对直流配电网的电压波动进行平抑;最后,利用PSCAD/EMTDC进行仿真,验证了所提控制方法的正确性和有效性。
DC distribution network can effectively integrate renewable energy sources （ RESs） into the utility and dispatch power to DC loads. As a result, it has been paid common attentions. To suppress the voltage fluctuation at buses caused by RESs, a DC electric spring （ ES） concept is presented for DC distribution network applications. By using a PWM Buck/Boost converter, the proposed ES can regulate the voltage of controllable load at its terminal bus. The power consumption of the controllable load can track and compensate the intermittent power generation of RESs. Because the intermittent power can be balanced by the local load and cannot flow in the network, the voltage fluctuation at buses can be naturally suppressed. In this paper, aiming to a typical DC distribution network, the physical model and the circuit model of the ES are built. Then a detailed mathematical model is proposed to analyze the factors influencing the voltage fluctuation. Schematic topology, control scheme, parameter design, and controllable boundary of the ES are then proposed to suppress the voltage fluctuation. Validation and effectiveness of the proposed models and approaches are confirmed by the simulated results of PSCAD/EMTDC.
出处
《电工技术学报》
EI
CSCD
北大核心
2016年第17期23-31,共9页
Transactions of China Electrotechnical Society
基金
国家重点基础研究发展计划(973项目)(2012CB215200)
中央高校基本科研业务费专项基金(106112015CDJXY150005
CDJZR12150074)资助项目
关键词
直流配电网
可再生能源
电压波动抑制
电气弹簧
可控负荷
DC distribution network, renewable energy resource, voltage fluctuation suppression, electric spring, controllable load
作者简介
曾正男,1986年生,博士,讲师,研究方向为分布式发电与微电网、电能质量、并网逆变器.E-mail：zengerzheng@126.com（通信作者）
邵伟华男,1991年生,博士研究生,研究方向为柔性直流输电、电力电子器件可靠性.E-mail：shaoweihuacqu@cqu.edu.cn
