固态变压器中隔离双向DC/DC变换器扩展移相下虚拟电流控制策略

SOLID-STATE TRANSFORMER IN ISOLATED BIDIRECTIONAL DC/DC CONVERTER EXTENDED UNDER PHASE SHIFT VIRTUAL CURRENT CONTROL STRATEGY

该文以固态变压器后级隔离双向DC/DC变换器为重点研究对象,提出一种扩展移相下虚拟电流控制策略。通过分析后级变换器在扩展移相传输功率下相移量关系以获得最小电流应力最优解来提高变换器的传输效率,减少器件损耗。同时通过虚拟电流控制思想在线估算传输功率来提高系统动态响应性能,减少电流传感器使用。最后,对该文所提出的扩展移相下虚拟电流控制与扩展移相控制进行实验对比分析,验证了扩展移相下虚拟电流控制策略具有降低电流应力,显著提高变换器的动态响应的优点。

In this paper,a virtual current control strategy under extended phase shift is proposed,which focuses on the isolated bidirectional DC/DC converter of solid-state transformer.By analyzing the phase shift relationship of the post-stage converter under the extended phase shift transmission power,the optimal solution of the minimum current stress is obtained to improve the transmission efficiency of the converter and reduce the device loss.At the same time,the virtual current control idea is used to estimate the transmission power online to improve the dynamic response performance of the system and reduce the use of current sensors.Finally,the experimental comparison between the virtual current control and the extended phase shift control under the extended phase shift is carried out.It is verified that the virtual current control strategy under the extended phase shift has the advantages of reducing the current stress and significantly improving the dynamic response of the converter.