Simple Innovative Method for Online Condition Monitoring of IGBTs in Back-to-Back Converters

The reliability of power electronic based converters has become increasingly important due to their wide-spread use in industry. An effective method to increase the availability of converters is to use condition monitoring systems for planning scheduled maintenances. This paper provides a method to monitor the condition of IGBTs in a back-to-back converter based on their on-state voltage measurement. Using the proposed system adds limited number of elements to the circuit but can be implemented independent from the converter. Considering the converter topology has made the proposed method applicable for condition monitoring of switches in different back-to-back converters. This advantage significantly reduces the cost of the condition monitoring process making it cost-feasible for cheaper converters. The simulations are performed to prove the performance of the proposed circuit, and the results are presented to confirm the accuracy of the measurement of the on-state voltage.