This paper proposes a diagnostic and fault-tolerant method for an open-fault condition in dual inverters with open-end winding interior permanent magnet synchronous motors (OEW-IPMSMs). Certain switch pairs show similar behavior in the output current in an open-fault condition due to the structural characteristics of the two-level dual inverter. This work presents a method for detecting open-fault conditions and ensuring a fault-tolerant operation. The proposed method is applied in dual inverters with isolated voltage sources for driving OEW-IPMSM. In the event of an open-fault condition, a pair of switches containing the faulty switch is identified based on the stator current. Subsequently, the switch with the open-fault condition is determined, and fault-tolerant control for a faulty switch is immediately performed through a single-mode operation using zero-voltage vectors. The effectiveness of the proposed detection and tolerant control method is confirmed through simulation and experimental results.
This work was supported by the Korea Institute of Energy Technology Evaluation and Planning (K500000110). ETEP) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea (No. 20225