摘要
将模块化多电平换流器(MMC)应用于船舶中压直流电力系统时,由于子模块数较少,使用传统的最近电平逼近调制(NLM)策略,输出电压谐波含量大,电压畸变程度较高。为此,分析了最近电平脉宽调制(NL-PWM)策略的原理与特点,选择NL-PWM作为船用MMC调制策略,利用控制变量法改变子模块个数、桥臂电感参数以及电压调制比改善输出电压的谐波。在Matlab/Simulink环境下,搭建MMC逆变侧仿真模型,对NL-PWM调制策略进行仿真。结果表明,该MMC调制策略适合应用于船舶中压直流电力系统电能变换,能够有效提升直流电力系统电能质量,提高直流母线电压稳定性。
When modular multilevel converter(MMC)is applied to marine medium voltage direct current power system,the traditional nearest level modulation(NLM)strategy leands to large harmonic content of output voltage and high voltage distortion due to the small number of sub modules.Therefore,nearest level-pulse width modulation(NL-PWM)is selected as marine MMC modulation strategy by analyzing the principles and characteristics of NL-PWM strategies.The control variable method is used to change the number of sub modules,bridge arm inductance parameters and voltage modulation ratio to improve the harmonic of output voltage.In the Matlab/Simulink environment,the simulation model of MMC inverter side is establised to simulate the NL-PWM modulation strategy.The simulation results show that the MMC modulation strategy is suitable for the application of power conversion in ship medium voltage direct current power system,and can effectively improve the power quality of direct current power system and the voltage stability of direct current bus.
作者
李闯
郭燚
卓秀
LI Chuang;GUO Yi;ZHUO Xiu(Logistics Engineering College,Shanghai Maritime University,Shanghai 201306,China)
出处
《上海电机学院学报》
2021年第6期318-324,共7页
Journal of Shanghai Dianji University
基金
上海市科学技术委员会科研资助项目(19040501700)。
