MW级LLC谐振式光伏并网变流器及控制策略研究  

Research on MW LLC Resonant Photovoltaic Grid Connected Converter and Its Control Strategy

作　　者：张振兴 常忠廷 甄帅 何青连 ZHANG Zhen-xing;CHANG Zhong-ting;ZHEN Shuai;HE Qing-lian(XJ Electric Co.,Ltd.,Xuchang 461000,China)

机构地区：[1]许继电气股份有限公司,河南许昌461000

出　　处：《电力电子技术》2023年第3期76-79,共4页Power Electronics

摘　　要：在“双碳”目标的大环境下,交直流混合微电网将是新能源发电发展的方向。为提供可靠性高、电压等级高、交直流交互能力强的并网设备,设计了兆瓦级LLC谐振式变流器,变流器可直接连接10 kV交流配电网。首先介绍了LLC谐振式变流器的主拓扑结构,并对高频隔离DC/DC模组功率单元进行了分析说明,然后根据变流器的实际工况,给出了其运行模式,研究设计了适用于该拓扑结构的移相启动控制策略和正常运行控制策略,并针对交流侧三相不平衡问题,制定了对应的均压控制策略。最后,研制了500 kVA/AC 10 kV/DC 750V实验系统,验证了所提拓扑结构和控制策略的正确性和有效性,为新能源并网提供新的实现方案。In the environment of"double carbon"goal,AC/DC hybrid microgrid will be the development direction of new energy power generation.In order to provide grid connected equipment with high reliability,high voltage level and strong AC/DC interaction ability,MW LLC resonant converter is designed,which can be directly connected to 1O kV AC distribution network.Firstly,the main topology of LLC resonant converter is introduced,and the power unit of high frequency isolated DC/DC module is analyzed and explained.Then,according to the actual working condition of the converter,its operation mode is given,and the phase-shift start control strategy and normal operation control strategy suitable for the topology are studied and designed.Aiming at the three-phase imbalance on the AC side,the corresponding voltage sharing control strategy is formulated.Finally,a 500 kVA/AC 10 kV/DC 750 V experimental system is developed,which verifies the correctness and effectiveness of the proposed topology and control strategy,and provides a new implementation scheme for new energy grid connection.

关 键 词：变流器 高频隔离 移相启动 控制策略 

分 类 号：TM46[电气工程—电器]