向微网供电的直流系统控制模式无缝切换策略  

Control Mode Seamless Transfer Strategy of DC System Supplying Power to Microgrid

作　　者：徐晓宇 王鑫[1] 蔡梦路 赵成勇[1] 宣佳卓 陆翌 XU Xiaoyu;WANG Xin;CAI Menglu;ZHAO Chengyong;XUAN Jiazhuo;LU Yi(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources,North China Electric Power University,Beijing 102206,China;State Grid Zhejiang Electric Power Co.,Ltd.Research Institute,Hangzhou 310014,China)

机构地区：[1]华北电力大学新能源电力系统国家重点实验室,北京102206 [2]国网浙江省电力有限公司电力科学研究院,杭州310014

出　　处：《高电压技术》2023年第2期747-758,共12页High Voltage Engineering

基　　金：国家电网有限公司科技项目(5500-202019066A-0-0-00)。

摘　　要：在微电网中,不同控制模式之间的切换是不可避免的,如何在不同控制模式之间切换时减小频率电压等指标的波动,对保证用户的供电质量至关重要。首先对不同控制策略之间的误差进行了量化分析,并给出了一种优化的控制策略无缝切换方法,包括dq轴/参考相角校准环节和大扰动瞬时功率补偿环节,对不同控制环的输出调制波进行修正/补偿。然后以某混合直流系统为例,利用上述补偿策略设计了可实现控制模式无缝切换的微网直流供电策略,包括混合直流系统无缝接入微网策略和大扰动时控制模式无缝切换策略。相比传统的无缝切换,该策略考虑了直流输电系统的送受端协调问题和不同控制模式之间的参考相角误差,并可提供一定的瞬时功率支撑,从而可减小因微网结构变化产生的波动。仿真结果表明该策略能够实现混合直流系统在不同控制模式之间的无缝切换,并且在微网发生大扰动时能够有效支撑系统的频率和电压。In microgrid, transfer between different control mode is unavoidable, and it is essential to reduce the impact of frequency and voltage while transferring to guarantee the power supply quality. Firstly, we quantify and analyze the errors between different control strategies and present an optimized method for seamless transfer, including a dq-axis/reference phase angle calibration and a large disturbance instantaneous power compensation, and implementing calibration/compensation of modulation wave. Then, taking a hybrid DC system as an example, we adopt the above compensation strategy to design a DC power supply strategy for isolated microgrid that can achieve seamless transfer of control mode.The strategy includes the seamless access of the hybrid DC system to the isolated network and the seamless transfer strategy of control mode during large disturbances. Compared with the traditional seamless strategy, this strategy considers the coordination of the feeder/receiver sides in the DC transmission system and the reference phase angle error between different control modes, and provides certain instantaneous power support, thus the impacts caused by changes in the microgrid structure are reduced. Simulation results show that this strategy can not only achieve seamless transfer between different control modes, but also effectively support the frequency and voltage of the system during large disturbances in an isolated network.

关 键 词：微网直流供电 无缝接入 无缝切换 混合直流 瞬时功率支援 

分 类 号：TM721.1[电气工程—电力系统及自动化]