中文摘要：

快速准确地获取电网基波正、负序分量及各次谐波分量,对并网变流器在电网非理想工况下的控制具有重要意义.为此,提出一种能够快速精确的提取电网基波正序、负序及各次谐波分量的正负序观测器技术.采用现代控制理论的状态观测方法,观测器在两相静止坐标系下实现,包含基波和各次谐波子观测器,能区分正、负序信号,可直接提取,无需额外正负序分离,不需要进行实时三角函数运算,易于数字实现.仿真和实验结果表明,文中提出的方法能够在电网不对称与存在谐波干扰的情况下准确提取出基波及各次谐波正负序分量,并且具有良好的动态性能.

英文摘要：

It is of great significance for the grid-connected converter control to extract the grid fundamental positive,negative sequence component and each harmonic component quickly and accurately under non-ideal conditions. In this regard,a positive and negative sequence observer technology is proposed. Based on the modern control theory methods of status observation,the observer is implemented in two-phase stationary reference frame and includes the fundamental and harmonic sub-observer. It can distinguish positive and negative sequence signal with the same angular frequency. It does not require real-time trigonometric functions and is easy to realize. The effectiveness of the proposed observer is demonstrated by the comparative experimental results which showthe accurate extraction for the fundamental positive,negative components and harmonic components and good dynamic performance under the unbalance and harmonic interference grid.