A Cascaded Hybrid Multilevel Inverter Incorporating a Reconfiguration Technique for Low Voltage DC Distribution Applications

  • Khomfoi, Surin
  • Received : 2015.01.24
  • Accepted : 2015.08.07
  • Published : 2016.01.20


A cascaded hybrid multilevel inverter including a reconfiguration technique for low voltage dc distribution applications is proposed in this paper. A PWM generation fault detection and reconfiguration paradigm after an inverter cell fault are developed by using only a single-chip controller. The proposed PWM technique is also modified to reduce switching losses. In addition, the proposed topology can reduce the number of required power switches compared to the conventional cascaded multilevel inverter. The proposed technique is validated by using a 3-kVA prototype. The switching losses of the proposed multilevel inverter are also investigated. The experimental results show that the proposed hybrid inverter can improve system efficiency, reliability and cost effectiveness. The efficiency of proposed system is 97.45% under the tested conditions. The proposed hybrid inverter topology is a promising method for low voltage dc distribution and can be applied for the multiple loads which are required in a data center or telecommunication building.


Cascaded hybrid inverter;Cascaded multilevel inverter;DC microgrid;Low Voltage DC Distribution;PWM paradigm;Reconfiguration technique


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