Design and implementation of ground power unit using a three‐level fault‐tolerant neutral point clamped inverter

• Published in: International journal of circuit theory and applications 2023-03, Vol.51 (3), p.1372-1388
• Main Authors: Abbaspour, Hasan, Madadi Kojabadi, Hossein
• Format: Article
• Language: English
• Subjects: Aircraft reliability; Aircraft survivability; Algorithms; availability; Circuit reliability; Clamping; Fault detection; fault detection (FD); fault‐tolerant multilevel inverter (FT‐MLI); ground power unit (GPU); Inverters; Power converters; reconfigure inverter; recovery capability; reliability; Reliability analysis; Reliability aspects; Switches
• ISSN: 0098-9886; 1097-007X
• DOI: 10.1002/cta.3459

Due to the widespread use of static power converters in various industries and sensitive applications such as ground power units (GPUs), it is essential that the inverters have high reliability. A failure in the inverters can cause undesirable consequences such as low performance, shutting down the system, and losing the stability of the entire system. On the other hand, in some critical industrial processes with high standstill costs and safety‐aspect concerns, such as aircraft, high reliability, and survivability of the system, are very important. Therefore, the use of fault‐tolerant (FT) inverters is inevitable in such applications. In this paper, using a three‐level fault‐tolerant neutral point clamped (FT‐NPC) inverter, the reliability of the GPUs is increased and it results in higher availability and continuous system performance. Furthermore, a simple automatic fault detection (FD) algorithm is presented by taking the inverter pole voltage as a FD parameter. The inverter is analyzed for open‐circuit fault in the switches, and the reliability of the FT‐NPC inverter is compared with the classic inverter. The simulation and experimental results of the 2‐kVA converter prototype are presented to confirm the FT inverter performance and the proposed method. By applying the fault detection scheme (FD) to the ground power unit (GPU), the reliability and continuous service of GPU will be provided. In the proposed FD inverter, the output power will not be reduced in the case of switch open circuit faults. Meanwhile, the stability of GPU inverter will be improved by using multilevel neutral point clamped inverter.