ISOP型直流变压器的谐振网络分析与设计

Analysis and Design of Resonance Network of ISOP DC Transformer

为实现低压器件在高压电能变换领域的应用,采用基于模块化ISOP(输入串联输出并联)拓扑的直流变压器技术方案,实现中压直流配电网和低压直流配电网之间电压等级变换和功率双向传输。直流变压器的子单元为全桥子模块拓扑结构,采用串联谐振软开关技术,半导体器件工作在ZVS(零电压开通)和近似ZCS(零电流关断)软开关工作状态,效率高,通过定频同步控制和合理的谐振参数设计,在负载动态变化时实现了输出电压稳定。设计并生产了一台500 kW,±10 kV/750 V直流变压器,试验验证了谐振网络理论分析和参数设计方法的正确性和可行性。

In order to realize the application of low-voltage devices in the field of high-voltage power conversion, a DC transformer technology scheme based on modular input series output parallel(ISOP) topology is adopted to realize voltage degree conversion and power bidirectional transmission between medium and low voltage DC distribution networks. The sub-unit of the DC transformer is a full-bridge sub-module topology,which adopts series resonant soft switching technology. The semiconductor device which works in ZVS and approximate ZCS soft-switching working state has high efficiency, Through the fixed-frequency synchronization control and rational resonant parameter design, output voltage stability is achieved when the load changes dynamically. A 500 kW,±10 kV/750 V DC transformer was designed and produced. The experimental results verify the correctness and feasibility of the theoretical analysis and parameter design method of the resonant network.