单相逆变器随机PWM选择性消谐滞环随机扩频方法  

A Novel Hysteresis Random Spread-Spectrum Method in Random PWM Selective Harmonic Elimination for Single-Phase Inverter

作　　者：李国华[1,2] 刘春武 汪玉凤 Li Guohua;Liu Chunwu;Wang Yufeng(College of Electrical and Control Engineering Liaoning Technical University,Huludao 125105 China;College of Mechanical Engineering Liaoning Technical University,Fuxin 123000 China)

机构地区：[1]辽宁工程技术大学电气与控制工程学院,葫芦岛125105 [2]辽宁工程技术大学机械工程学院,阜新123000

出　　处：《电工技术学报》2021年第6期1279-1289,共11页Transactions of China Electrotechnical Society

基　　金：National Natural Science Foundation of China(51307076);Natural Science Foundation of Liaoning Province,China(20180550268)。

摘　　要：在随机脉冲宽度调制(RPWM)中,要求逆变器的瞬时开关频率分布在较宽的频率范围内,以获得较好的随机性。然而,当开关频率持续偏高时,逆变器的开关损耗将会增加;当开关频率持续较低时,会引起输出电流纹波的增加。现有的RPWM选择性谐波消除方法在随机扩频的过程中不能有效地控制逆变器的开关频率。该文提出一种单相逆变器RPWM选择性消谐滞环随机扩频方法。根据RPWM策略中有效随机数k与开关频率的关系,合理选择随机数k,既可以保证逆变器瞬时开关频率在较宽的范围内随机分布,又可以将平均开关频率控制在预先设定的频率范围内。在RPWM选择性消谐过程中,当开关频率较低而引起电流纹波增加时,该方法可以通过提高平均开关频率来减小纹波。In random pulse width modulation(RPWM),the instantaneous switching frequency of inverter is required to be distributed in a wide frequency range for better randomness.However,when the switching frequency continues to be high,the switching loss will be increased.When the switching frequency continues to be low,the increase of output current ripples will be introduced.The existing selective harmonic elimination method in RPWM cannot effectively control the switching frequency of inverter as needed in the process of random spread-spectrum.In this paper,a novel hysteresis random spread-spectrum method in RPWM selective harmonic elimination for single-phase inverter is proposed.With the reasonably chosen random number(k)according to the relationship between k and switching frequency in RPWM,the proposed method can guarantee that the instantaneous switching frequency is randomly distributed over a wide range and the average switching frequency can be controlled within a preset range.When the current ripples are large due to low switching frequency in RPWM selective harmonic elimination method,the average switching frequency can be increased to reduce it.

关 键 词：滞环随机扩频 随机脉宽调制(RPWM) 选择性谐波消除 单相逆变器 

分 类 号：TM46[电气工程—电器]