Research of the equivalent relationship between the space vector and the triangular carrier-based PWM modulation strategies in the flying capacitor multilevel inverters

ABSTRACT

The equivalent relationship between the carrier-based modulation (CBPWM) and the space vector modulation (SVPWM) based on the flying capacitor multilevel inverters has not been analysed systematically. Due to the redundancies of the flying capacitor multilevel inverters, this paper firstly focuses on the switching sequence and the working ratio of each switching state and then proposes a novel method of decomposing modulation wave. This method can distribute the ratio of redundancies arbitrarily to satisfy the requirements of the output. Taking three- and five-level inverters as examples, by injecting a zero-sequence voltage into the CBPWM modulation wave and then decomposing the new modulation wave, we can get the same sequence of SVPWM modulation. This method takes the advantages of using simple CBPWM to realise the complex output of SVPWM, such as double- and quadruple-frequency output. At last, we deduce the equivalent relationship between the SVPWM and CBPWM in n-level with an arbitrary number of segments. Experimental results verify the correctness of the equivalent relationship.     

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信息安全风险评估方法研究

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双向防水型数字缆的设计及开发

本文重点介绍了江苏亨通线缆科技有限公司结合目前特殊场合布线的需求,并从产品性能及成本角度出发,开发出了一种双向防水型数字电缆,并简单阐述了该产品的工艺设计、电气性能特点和生产过程中关键开发技术的控制。     

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使用梯度相似度的激光干扰图像评估

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