A new closed-loop regulation method dedicated to piezoelectric resonators based isolated DC-DC converter

Magnetic components are widely used in power electronics. Yet, their downscaling with frequency becomes moderate from 100 kHz, which limits the possibility of reducing the volume of the passive components in power converters. Therefore, a major breakthrough is under investigation to replace such components with piezoelectric resonators. Though, the conversion implies the use of more complex conversion cycles. In the literature, they include at least one synchronisation on the mechanical strain and closed-loops to regulate the zero voltage switching operations and the power flow. In this paper, a new technique involving a single closedloop control without any mechanical synchronisation is presented. To achieve this, a novel eight-phase conversion cycle has been designed and applied to a Dual active Bridge Isolated Piezoelectric Resonators Converter (DB-IPRC). This novel cycle simplifies the control without compromising the converter’s power level and efficiency. The following study first introduces an analytical model that models the converter’s switching operations. Then, a new analytical function is presented to estimate the converter’s operating frequency. Subsequently, exploiting the unique features of the new switching sequence, the single closed-loop control is experienced on a DB-IPRC. The paper concludes on unchanged efficiency and power level compared to the open loop fine-tuned configuration.