The presence of renewable energy resources in LV distribution networks may lead to a distribution transformer,also known as a Smart Transformer(ST),experiencing the bidirectional power flow.Therefore,the ST must have ...The presence of renewable energy resources in LV distribution networks may lead to a distribution transformer,also known as a Smart Transformer(ST),experiencing the bidirectional power flow.Therefore,the ST must have the capability to operate in both directions.However,the reverse power is less as compared to the forward power,thus the design of ST with the same capacity in both directions increases the hardware cost and decreases the system efficiency.This paper proposes a Hybrid-modular-ST(H-ST),composed of a mixed use of single active bridge-based series resonant converter and dual active bridge instead of complete use of uni-or bi-directional converter adopted in the conventional solid-state-transformer.Based on the proposed H-ST,the impacts of power imbalance among cascaded modules in reverse operation mode are analyzed and then an effective solution based on reactive power compensation combined with the characteristics of the proposed architecture is adopted.The simulation and experimental results clearly validate the effectiveness and feasibility of the theoretical analyses.展开更多
为了更好地将分布式电源与负荷接入直流配电网,并提升功率传输效率,针对双向有源桥(dual active bridge,DAB)变换器的运行控制,研究其回流功率的优化控制技术策略。建立基于扩展移相控制的DAB变换器的传输功率与回流功率数学模型,详细...为了更好地将分布式电源与负荷接入直流配电网,并提升功率传输效率,针对双向有源桥(dual active bridge,DAB)变换器的运行控制,研究其回流功率的优化控制技术策略。建立基于扩展移相控制的DAB变换器的传输功率与回流功率数学模型,详细阐述回流功率的产生机理,在传输功率特性中引入电路的回流功率特性。其次,分析不同电压转换比下,回流功率与传输功率的耦合关系,提出DAB变换器的回流功率最优控制模型。搭建DAB变换器的实验样机,分析最优回流功率控制下的变换器工作特性,对比研究不同控制策略下DAB内部的回流功率,验证了所提回流功率最优控制模型的有效性。展开更多
基金supported in part by National Key Research&Development Project of China(2017YFE0134300)in part by Shanghai 2022 Science and Technology Innovation Action Plan-Star Cultivation(Sailing Program)(22YF1415700)in part by the National Natural Science Foundation of China under Grant 52307215.
文摘The presence of renewable energy resources in LV distribution networks may lead to a distribution transformer,also known as a Smart Transformer(ST),experiencing the bidirectional power flow.Therefore,the ST must have the capability to operate in both directions.However,the reverse power is less as compared to the forward power,thus the design of ST with the same capacity in both directions increases the hardware cost and decreases the system efficiency.This paper proposes a Hybrid-modular-ST(H-ST),composed of a mixed use of single active bridge-based series resonant converter and dual active bridge instead of complete use of uni-or bi-directional converter adopted in the conventional solid-state-transformer.Based on the proposed H-ST,the impacts of power imbalance among cascaded modules in reverse operation mode are analyzed and then an effective solution based on reactive power compensation combined with the characteristics of the proposed architecture is adopted.The simulation and experimental results clearly validate the effectiveness and feasibility of the theoretical analyses.
文摘为了更好地将分布式电源与负荷接入直流配电网,并提升功率传输效率,针对双向有源桥(dual active bridge,DAB)变换器的运行控制,研究其回流功率的优化控制技术策略。建立基于扩展移相控制的DAB变换器的传输功率与回流功率数学模型,详细阐述回流功率的产生机理,在传输功率特性中引入电路的回流功率特性。其次,分析不同电压转换比下,回流功率与传输功率的耦合关系,提出DAB变换器的回流功率最优控制模型。搭建DAB变换器的实验样机,分析最优回流功率控制下的变换器工作特性,对比研究不同控制策略下DAB内部的回流功率,验证了所提回流功率最优控制模型的有效性。
