Zero Voltage Switching for High Power Threephase Inductive Power Transfer with a Dual Active Bridge

Journal article, 2024

Inductive power transfer (IPT) technology used for charging electric vehicles faces challenges in transferring high power because the power capacity and switching losses of high-frequency semiconductor devices are limiting factors. A three-phase system is a common high-power solution and soft switching is crucial for efficiency-oriented applications with high switching frequencies. In addition, dual active bridge (DAB) topology is a suitable topology for soft switching and has advantages in controllability and high efficiency. Therefore, to obtain higher power and efficiency, this paper studies the zero voltage switching (ZVS) of a three-phase inductive power transfer system with a dual active bridge. The three-phase IPT system with a DAB is different from both the normal three-phase DAB converter and the single-phase IPT system with a DAB, so their ZVS conditions and ranges are also different and need to be studied. This paper investigates the conditions and operating range for realizing zero voltage switching of the three-phase IPT system with a DAB. Based on this, the efficiency of the system is improved by changing the load angle between the primary and secondary sides. Finally, a 60 kW three-phase IPT system with a DAB is built, and the experimental verification of the study is conducted.