摘要
针对传统基于虚拟电机磁链的无电压传感器方法电压波动较大问题,结合二阶广义积分原理与占空比信号提出一种电压观测器以代替电压传感器获取更加精准的网侧电压信息。依据瞬时功率理论,在两相静止坐标系下,采用基于PQ开环的准直接功率电压定向控制策略,实现了并网变流器的四象限工作状态运行,电流内环采用比例谐振控制器保证指令电流快速无差跟踪。对比分析网侧电压信号谐波畸变率,实验波形表明:所提方法不需要电压传感器与电流解耦控制环节,且谐波含量低,可获得较传统方法更准确的网侧电压信号,提高了系统运行的稳定性与可靠性。
For the large voltage fluctuation of the traditional method based on the virtual motor flux link- age, a voltage observer based on the second order generalized integral （SOGI） principle and duty cycle signal was proposed to replace the voltage sensor in order to obtain more accurate information of the volt- age of the network side. According to the theory of instantaneous power, the quasi-direct power voltage di- rectional control strategy based on PQ open-loop was adopted in the two-phase stationary coordinate sys- tem, and the four-quadrant operation state of the grid-connected converter was realized. Meanwhile, the application of proportional resonant controller to ensure current reference could keep tracking grid cur- rent. The result shows that the proposed method need neither the voltage sensor nor the current decou- piing, the network side voltage signal with low harmonic content can be obtained more accurately than the traditional method, which improves the stability and reliability of system operation.
出处
《电机与控制学报》
EI
CSCD
北大核心
2017年第5期89-96,共8页
Electric Machines and Control
基金
广西科学研究与技术开发项目(1598008-3)
南宁市科学研究与技术开发计划(20131048)
关键词
无电压传感器
两相静止坐标系
准直接功率控制
二阶广义积分器
占空比
比例谐振
vohage sensorless
αβ coordinate
quasi direct power control
second order generalized inte-gral
duty cycle
proportional resonant
