The switched capacitor differential boost inverter (SCDBI) is a single-stage single-phase step-up bidirectional inverter, in which the voltage gain lifts as the number of switched-capacitor cells increases. When this inverter is applied to grid-connection as herein proposed, its capacitive output-voltage feature enables a grid current with low ripple, even when a simple L filter is employed. In addition, the SCDBI is free of high frequency common mode voltage, which mitigate the common mode current circulation between the input and output sources. These attributes favor the employment of this inverter in grid-connected systems. Although these are positive aspects, the SCBDI also presents some challenges related to its nonlinear voltage gain and high-order dynamic models. In this paper, a reduced order dynamic model is derived to simplify the SCDBI modeling and a static gain linearization technique is proposed in order to simplify the control strategy, therefore enabling the use of classical control methods. Experimental results achieved from a 250 W prototype, dc input voltage of 60 V, and electrical grid of 220 V rms, corroborated the inverter operation, in which a peak efficiency of 90% and a grid-current total harmonic distortion less than 5% were reached.

中文翻译：

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应用于并网的开关电容差动升压逆变器

开关电容差分升压逆变器 (SCDBI) 是一种单级单相升压双向逆变器，其中电压增益随着开关电容单元数量的增加而提升。当该逆变器应用于本文提出的并网时，其容性输出电压特性使电网电流具有低纹波，即使采用简单的 L 滤波器也是如此。此外，SCDBI 没有高频共模电压，这减轻了输入和输出源之间的共模电流循环。这些特性有利于在并网系统中使用该逆变器。尽管这些都是积极的方面，但 SCBDI 也提出了一些与其非线性电压增益和高阶动态模型相关的挑战。在本文中，推导出降阶动态模型以简化 SCDBI 建模，并提出静态增益线性化技术以简化控制策略，从而允许使用经典控制方法。从 250 W 原型、60 V 直流输入电压和 220 V rms 电网获得的实验结果证实了逆变器的运行，其中峰值效率为 90%，电网电流总谐波失真小于 5%到达。