Insulated Signal Transmission System with Near-field Resonant Coupler to Drive High-voltage Power Devices

Abstract

An insulated signal transmission system using a near-field resonant coupler was developed for providing driving signal transmission to control power switching devices. The resonant coupling in the near-field can reduce the unwanted leakage that prevents conventional wireless systems from being deployed inside the metal housing of the switching devices. The focus was on the parasitic capacitance of the resonant coupler because the capacitance needs to be reduced for suppression of the noise current caused by the switching devices. An equivalent circuit model of the resonant coupler was introduced to simulate the capacitance, and validated by showing agreement between the calculated value of 0.76 pF and the measured value of 0.80 pF. An insulated communication module configured with the resonant couplers and two transceivers on the PCB was fabricated. The module demonstrated the switching operation of 3.3 kV-1200 A insulated-gate bipolar transistors (IGBTs) without disturbances between the high-power switching IGBTs and RF transceivers.