隔离型双向直流变换器的最小回流功率移相控制方法

The Phase-Shifted Control Method of Isolated Bidirectional DC-DC Converter with Minimum Backflow Power

降低隔离型双向直流变换器的回流功率以提高变换效率,对拓展隔离型双向直流变换器在直流配电网中的应用具有重要意义。首先,阐述双移相控制的工作原理和变换器回流功率产生的原理,建立传输功率和电源侧、负载侧回流功率的数学模型,分析减小回流功率对减小电流应力、提高效率所起的作用。其次,提出一种最小回流功率移相控制方法。在传输相同功率的条件下,相比双移相控制方法,该方法控制的功率运行点可实现回流功率最小。最后,在所搭建的2k W实验平台上进行实验验证,结果表明,所提控制方法在不同工况下均能实现最小回流功率运行,从而有效地减小了电流应力及功率损耗,提高了效率。

Reducing backflow power of isolated bidirectional dc-dc converter （IBDC） can improve the transmission efficiency. It is important to extend the application of IBDC in dc power distribution network. Firstly, the principles of dual-phase-shift control and backflow power production are analyzed. Then the mathematical models of the transmission power, power supply side backflow and load side backflow are established. Accordingly, a minimum backflow power phase shift control method is proposed to decrease current stress and improve efficiency. Under the same power transfer capability, the proposed method can control operating points to realize the minimum backflow power compared with the dual-phase-shift control. Finally, by using a 2kW IBDC porotype, the experimental results show that the proposed control method can achieve the minimum backflow power operation in different conditions, which can effectively reduce the current stress and power loss and improve efficiency.