摘要
针对常规锁相方法在电网异常时不能有效地检测出电网相位和幅值的问题,采用自适应滤波器提取电网电压的正序基波分量,根据正序基波分量检测电网的相位和幅值.针对电网相位突变的情况,在分析锁相环数学模型的基础上,提出了电网正序电压的q轴分量的直接前馈方法,有效地提高了系统的动态特性和相位检测精度,并从理论上分析了电网幅值变化对锁相环的稳定性和稳定裕度的影响.仿真结果证明了所提锁相方法的可行性.
For the problem that an ordinary phase-locked method cannot effectively detect the phases and the amplitudes of grid voltages when grid voltages are distorted, a self-adaptive filter is adopted to extract positive sequence fundamental components of grid voltages, and then the phases and the amplitudes of the grid voltages are detected according to the positive sequence fundamental voltage components. For the suddenly changing phase of the grid, a direct feedforward method for the q axis component of grid voltages is proposed based on the analysis of the mathematical model of the phase-locked loop. The dynamic performance of the phase-locked loop and the precision of phase detection are both improved effectively. The effects on the stability performance and the stability margin of the phase-locked loop brought by the variation of grid voltage amplitude are analyzed theoretically. The feasibility of the proposed phase-locked method is verified by simulation results.
出处
《信息与控制》
CSCD
北大核心
2013年第3期345-350,共6页
Information and Control
基金
湖北省教育厅科学技术研究项目(B20122506)
