无PFC LED球泡灯滤波电路对电流谐波的影响研究

无功率因数矫正(PFC)LED球泡灯广泛用于家庭及小型商业用户,其驱动电路结构通常包括整流、滤波和驱动。基于无PFC LED球泡灯常用的三种不同滤波结构(π型、倒L型、C型)的电路拓扑,通过整流滤波电路产生谐波表达式,计算3次、5次、7次和9次谐波初相角和电流畸变率;分析滤波电路器件参数对公共连接点(PCC)处电流谐波相角及畸变率的影响。研究结果表明,滤波参数和各次谐波电流初相角、含量具有关联性,不同的滤波结构的LED球泡灯组合存在谐波的叠加和消除规律。

Research on the Influence of PFC-free LED Bulb Filter Circuit on Current Harmonic

PFC-free LED bulb is widely used in home and small business users,and its drive circuit structure usually includes rectified,filtered and driven.The 3th,5th,7th and 9th harmonic initial phase angle and current distortion rate were calculated by generating the harmonic expression through the rectifier filter circuit based on the circuit topology of three different filter structures(π-type,inverted L-type,C-type)commonly used in PFC-free LED bulb;the influence of filter circuit device parameters on the current harmonic phase angle and distortion rate at point of common coupling(PCC)was analyzed.The research results show that the filtering parameters are related to the initial phase angle and content of each harmonic.The LED bulb combinations with different filtering structures have the rules of superposition and elimination of harmonics.