摘要
脉冲宽度调制PWM(pulse width modulation)变频器、开关电源等电力电子设备的规模化接入电网,将向电网注入大量超高次谐波,由此产生的电磁干扰问题势必越发严重。对LED驱动电路超高次谐波发射机理进行了深入研究,首先通过对电流控制模式LED驱动电路建模,求解出了MOSFET任意开关时刻,并建立了谐波源等效模型;然后分析电路在不同工作状态时,超高次谐波源对网侧谐波含量的影响,求解出了对应的开关函数以及网侧超高次谐波电流含量表达式;最后通过仿真验证了各参数对网侧超高次谐波的影响。
PWM converters,switching power supply,and other power electronic equipment will inject a large quantity of supraharmonics into power grid when they are connected to the grid on a large scale,resulting in serious electromagnetic interference at an increasing rate.In this paper,the supraharmonics emission mechanism of an LED drive circuit is studied in depth.First,by modeling the LED drive circuit in current-controlled state,the solution of arbitrary switching time of MOSFET is obtained,and a harmonic source equivalent model is established.Then,the influences of supraharmonics source on the grid-side harmonic content are analyzed when the circuit works in different states.The corresponding switching function is obtained,and the expression of the grid-side supraharmonics current content is solved.Finally,the influences of parameters in the expression on the grid-side supraharmonics are verified through simulations.
作者
朱明星
张晓刚
ZHU Mingxing;ZHANG Xiaogang(Research Center of Power Quality Engineering of Ministry of Education,Anhui University,Hefei 230601,China)
出处
《电源学报》
CSCD
北大核心
2021年第2期198-206,共9页
Journal of Power Supply
基金
国家电网公司总部科技资助项目(52182018000H)。
关键词
开关电源
超高次谐波
开关函数
恒流驱动
谐波源等效
switching power supply
supraharmonics
switching function
constant-current drive
harmonic source equivalence
