第41卷第3期陕西科技大学学报Vol.41No.32023年6月JournalofShaanxiUniversityofScience&TechnologyJun.2023*文章编号:2096-398X(2023)03-0172-08新型两单元逆变器的调制策略及其功率均衡方法胡文华,陈卓凡,丁文斌(华东交通大学电气与自动化工程学院,江西南昌330013)摘要:传统两单元级联H桥逆变器输出电平数较少,且在传统载波移幅调制策略下存在各单元输出功率不均衡的问题.针对上述问题,提出了一种不对称级联八开关逆变器拓扑结构,并针对所提拓扑提出了一种改进型POD-PWM功率均衡调制策略.该逆变器由两个相同的不对称八开关七电平逆变器级联而成,能够输出十三电平的电压,在减少开关管的同时实现了一个输出周期内各单元之间输出功率的均衡.最后通过仿真与实验验证证明了所提拓扑及其功率均衡方法的正确性与可行性.关键词:多电平逆变器;新型拓扑;改进型调制策略;倍频调制;功率均衡中图分类号:TM464文献标志码:ANovelmodulationstrategyandpowerbalancemethodfortwo-unitinverterHUWen-hua,CHENZhuo-fan,DINGWen-bin(SchoolofElectricalandAutomationEngineering,EastChinaJiaotongUniversity,Nanchang330013,China)Abstract:Thetraditionaltwo-unitcascadedH-bridgeinverterhadasmallnumberofoutputlevels,andtheoutputpowerofeachunitwasunbalancedunderthetraditionalcarrierampli-tudeshiftmodulationstrategy.Tosolvetheseproblems,thispaperproposedanasymmetriccascadedeightswitchinvertertopology,andproposedanimprovedPOD-PWMpowerequali-zationmodulationstrategyfortheproposedtopology.Theinverterwascascadedbytwoiden-ticalasymmetriceightswitchsevenlevelinverters,whichcouldoutput13levelvoltage,andachievedtheoutputpowerbalancebetweenunitsinanoutputcyclewhilereducingthenum-berofswitches.Finally,thecorrectnessandfeasibilityoftheproposedtopologyanditspowerequalizationmethodwasverifiedbysimulationandexperiment.Keywords:multilevelinverters;newtopology;improvedmodulationstrategy;frequencydoublingmodulation;powerbalance0引言随着近年来新能源发电的蓬勃发展[1,2],电力行业对多电平逆变器的需求也不断提高,多电平逆变器广泛应用于无功补偿、中压大功率传动及光伏并网等领域[3-5],它具有输出电平数多、输出波形质量高、开关管电压应力低且易于模块化等优点.传统的多电平逆变器主要分为飞跨电容型(FlyingCap...
