Abstract: In preferred embodiments, a short circuit protection system for a wide-band gap power electronics converter composed of multiple half-bridge legs is presented. The main approaches of the system are a single point of monitoring (SPM) for multiple switching legs, and non-invasive implementation and fast speed of the short circuit current detection. Ultra-high frequency (UHF) AC current, tens or hundreds of MHz, flowing through the DC-link capacitors represents the short circuit current occurred at the multiple switching legs. To capture the UHF AC current, a non-invasive MHz bandwidth magnetic current sensor is applied to the PCB conduction path of the converter. In this digest, simulation results of the short circuit current representation through the DC-link network and the magnetic field distribution in PCB layout for the selection of the proper location of the detection, and experimental results showing the UHF AC current sensing performance are presented.

Abstract: Various examples are provided for on-state voltage sensing for in-situ monitoring and prognostics. In one example, an on-state monitoring circuit includes clamping circuitry including high-side and low-side voltage clamping circuits associated with high-side and low-side switching devices of a half-bridge (HB) leg of an converter, on-state voltage circuitry including high-side and low-side voltage measurement circuits, the high-side and low-side circuits referenced to the positive and negative buses of the converter respectively, and output circuitry including high-side and low-side isolation circuits that provide isolated outputs referenced to a control ground of the converter.