Open-circuit Fault Diagnosis Strategy Based on Current Reconstruction with A Single Current Sensor for Voltage Source Inverter

The parameter difference and cost of multiple current sensors exist in the open circuit fault diagnosis of the inverter. This paper proposes an open-circuit fault diagnosis strategy based on current reconstruction with a single current sensor for the voltage source inverter. Through the parallelogram law analysis of the voltage vectors under different fault states, the phase angle of the voltage vector under the fault is obtained. At the same time, the reverse complementary vector is used to replace the zero vector to reconstruct the fault three-phase current in the current unsamplable area with a single current sensor. According to the fault voltage vector analysis and the reconstructed fault three-phase current, an open-circuit fault diagnose method is proposed based on average current vector. Simulation results verify the feasibility and reliability of the fault diagnosis strategy.