A Fast and Robust Open-Circuit Fault Detection Method for Voltage-Source-Inverter With Integrated High-Frequency Sensor

Efficient fault detection is essential for the safety and reliability of voltage source inverters (VSIs), particularly the rapid and robust detection of open-circuit faults (OCFs) under dynamic conditions. This study proposes a novel OCF detection method for VSI, employing a high-frequency (HF) sensor embedded in a traditional Hall current sensor to detect HF switching oscillations. First, the causal relationship between switching actions of power devices and HF current oscillation events was analyzed. Subsequently, an integrated HF current sensor is designed to capture HF oscillation currents, enabling OCF detection through signal integrity analysis of switching oscillation events with no need of gate signals. Finally, experimental validations on both insulated-gate bipolar transistor (IGBT) and silicon carbide (SiC) MOSFET platforms have confirmed the method’s efficacy. Detection and localization of OCFs in VSI systems can be achieved within 1–2 switching periods. Moreover, the method demonstrates robust performance under dynamic operating conditions and ensures nonintrusive safety.