中文摘要：

针对目前单相谐波电流检测方法存在的问题，对无锁相环谐波电流检测法进行了详细分析，提出了一种改进的无锁相环单相谐波电流检测方法。采用低通滤波器和均值滤波器串联的形式对原有低通滤波器进行优化，以提高检测精度和动态响应速度；采用基波电流反馈形式，以进一步提高动态响应速度。Matlab／Simulink下的仿真结果表明：所提方法确实可行，大大提高了检测精度和动态响应速度。

英文摘要：

Aiming at the problems of the single phase harmonic current detection method, analyzes the harmonic detection method without phase locked loop （PLL） and proposes an improved single-phase harmonic current detection method without PLL. The method combines low pass filter and mean filter in series form to optimize the original low-pass filter and improve the detection precision and dynamic response speed; and for further accelerating the dynamic response speed, the fundamental wave current feedback form is applied. Matlab/Simulink simulation results show that this method is feasible and greatly improves the detection accuracy and dynamic response speed.