CAJ | 학술논문

光伏逆变器由于受外界因素以及逆变器的一些内在因素的影响，导致逆变器对输入电压的要求很严格。传统的逆变器加变压器的方法和多级级联的方法不能够妥善解决输入电压适应性的问题。为满足对大范围直流电压输入变化的适应性要求，同时实现光伏并网逆变器逆变与升压两个功能，提出了一种新型的单相三开关光伏并网逆变器拓扑。采用高频开关器件和反激变换器，替换了传统笨重的工频升压变压器，使得逆变器的体积、重量及成本降低，易于集成，且提高了变换效率。实时波形反馈技术的闭环SPWM（sinusoidal pulse width modulation）控制方法，可提供快速响应。通过一个小的交流滤波器可获得低谐波失真的正弦输出。对理论分析结果进行仿真验证，结果表明该新型单相三开关光伏并网逆变器具有拓扑简单，适应大范围直流输入电压变化，可靠性高等优点。
광복역변기유우수외계인소이급역변기적일사내재인소적영향，도치역변기대수입전압적요구흔엄격。전통적역변기가변압기적방법화다급급련적방법불능구타선해결수입전압괄응성적문제。위만족대대범위직류전압수입변화적괄응성요구，동시실현광복병망역변기역변여승압량개공능，제출료일충신형적단상삼개관광복병망역변기탁복。채용고빈개관기건화반격변환기，체환료전통분중적공빈승압변압기，사득역변기적체적、중량급성본강저，역우집성，차제고료변환효솔。실시파형반궤기술적폐배SPWM（sinusoidal pulse width modulation）공제방법，가제공쾌속향응。통과일개소적교류려파기가획득저해파실진적정현수출。대이론분석결과진행방진험증，결과표명해신형단상삼개관광복병망역변기구유탁복간단，괄응대범위직류수입전압변화，가고성고등우점。
There are strict requirements of input voltage for a photovoltaic inverter due to some external effects and internal factors, and it is difficult to solve the problem of tolerance to varied input DC voltage properly through the traditional method of an inverter plus a transformer and multi-stage cascading. In order to meet the need of tole-rance to a widely varied input DC voltage and realize the function of inversion and step-up in photovoltaic grid-connected inverter, this paper puts forward a novel single-phase photovoltaic grid-connected inverter topology with three switches. High-frequency switches and fly-back converter were adopted to substitute the traditional bulky line frequency step-up transformer, which made the system easy to integrate with small volume, low weight and cost, and higher efficiency. The closed-loop sinusoidal PWM control method with real-time waveform feed-back technique can provide fast dynamic response. Through a small ac filter, the inverter achieved low-THD sinu-soidal output. Simulation results verify that the novel single-phase photovoltaic grid-connected inverter is fea-tured by simple structure and control, tolerance to a widely varied input DC voltage with high reliability.