Condition Monitoring of Power Electronic Systems Through Data Analysis of Measurement Signals and Control Output Variables

Abstract

A major disadvantage of existing condition monitoring methods is the need for additional sensors and measuring equipment. In this work, this disadvantage is eliminated by completely avoiding additional hardware. Instead, software-based methods from the field of machine learning are used. Therefore, measurement signals and control output variables are utilized which are acquired and processed in any power electronic system for the purpose of converter control. The publication focuses on two main converter components: power semiconductors and DC link capacitor. For each component, the aging mechanisms that have been studied in the literature are explained. Based on the aging mechanisms, the degradation indicators are identified. Then, a converter model is built that allows the variation of degradation indicators in order to analyze their effects on the available data set. These findings form the basis for mathematical models, which detect future failure mechanisms of this type during converter operation. The test setup must offer the possibility of generating reproducible failure cases in various components with the aid of additional failure equipment. Finally, failure mechanisms are intentionally introduced at the test bench in order to validate the methodology of the developed approach.

Advances in Capacitor Health Monitoring Techniques for Power Converters: A Review

“…The reported technique for estimation of the DC-link capacitor of these converters can be categorized as methods involving low-frequency voltage/current injection [75]- [78] and estimation of power loss in capacitor [43], [79]. A model-based approach is proposed in [80], [81], and measured current and voltage signals are processed in [82]- [90]. In [91]- [93], the charging/discharging profile is used to estimate capacitance in different motor drive systems.…”

“…Further, the relation between the stator temperature and resistance is utilized to incorporate the temperature effect. Another model-based approach is proposed in [81]. A mathematical model was developed By analyzing the time signal of the DC-link voltage to calculate changes in the capacitance of the DC-link capacitor during converter operation.…”

Semiconductor Devices Condition Monitoring Using Harmonics in Inverter Control Variables

“…Extra components may also introduce additional risk of failure to the overall system. To avoid adding extra circuits, D. Xiang et al [12] and F. Yüce et al [13], [14] exploited harmonics in the control variables as a precursor to monitor power semiconductor devices in a three-phase inverter. However, no general mathematical justification is provided, which limits the generalization of this method to a specific system.…”