Online diagnostics and condition monitoring in voltage source inverters

This paper presents a method for online diagnostics and monitoring in voltage source inverters. Single components of the inverter prone to failure and aging are investigated and analysed. The proposed method allows for real time statistics and determination of gradual changes that would be difficult to estimate in an offline mode. Power semiconductors and other components of the voltage source inverter are considered and a more complete state report of the system can be given in real time. Practical measurements prove that the suggested diagnosis and monitoring approach can significantly contribute to better knowledge about the system´s state and help to recognise and overcome dangerous and critical states of voltage source inverters. Hence better utilisation and a more reliable power electronic system are obtained