ABSTRACT With growing decentralized power generation, medium-voltage (MV) dc-dc converters are becoming increasingly important. A three-phase dual-active bridge (DAB3) is a promising topology for high-power MV applications. The semiconductor devices used in such converters at multi-megawatt level tend to be slow in switching. Hence, a considerable dead time between switching instants is required to avoid shoot-through in phase legs. This dead time forces the current to commutate to the freewheeling diodes and introduces a current dependence of the phase voltages. In this work, the effects of dead time on the operation of DAB3 are analysed in detail. The derived analytical expressions are used in the control development to compensate for the effects of dead time and hence achieve superior control performance. Measurements are carried out on a small-scale laboratory prototype to validate the derived operational modes and the effectiveness of the proposed dead time compensation.

中文翻译：

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三相双有源桥式DC-DC变换器死区时间建模与补偿

摘要 随着分散式发电的增长，中压 (MV) dc-dc 转换器变得越来越重要。三相双有源电桥 (DAB3) 是一种适用于大功率 MV 应用的有前途的拓扑结构。在这种多兆瓦级转换器中使用的半导体器件往往开关缓慢。因此，在开关瞬间之间需要相当长的死区时间以避免相腿中的直通。该死区时间迫使电流换向至续流二极管并引入相电压的电流依赖性。在这项工作中，详细分析了死区时间对 DAB3 操作的影响。导出的解析表达式用于控制开发，以补偿死区时间的影响，从而实现卓越的控制性能。