Modeling of Sensor Faults in Power Electronics Inverters and Impact Assessment on Power Quality

Abstract

Sensors are crucial for the operation of power electronics converters. Voltage and current sensors, widely used in power electronic converter systems, are prone to malfunction or failure mainly due to varying environmental conditions, broken connectors, and ageing of electronic circuit components. Therefore, it is important to characterize the behavior of these sensors under a number of possible faulty conditions and study their impact on the performance of the system. Further, the distinct behavior of such sensors, under different fault types, encourages us to correlate them with the generic fault models. In this paper, a root cause analysis for each type of sensor fault is presented and experimental validation for five fault models is performed, where the parameters of key components in the power electronics voltage and current sensor are intentionally modified to emulate a specific type of fault. Moreover, the impact of each fault on the power quality of Grid Side Converter (GSC) under various types and magnitudes of sensor faults are assessed and validated experimentally. The results of this work are useful to ensure the design for the reliability approach in power electronics converters and provide an assessment of the impact of a sensor failure in the overall operation of power electronics converters. Further, the impact of sensor faults in the overall operation of a power electronics converters give some directions to design algorithms that can improve the reliability and robustness of the power electronics converters.Index Terms-Circuit faults, DC-AC power converters, fault models, power quality, sensor systems.

Model-Based Fault Diagnosis Scheme for Current and Voltage Sensors in Grid Side Converters

“…A detailed discussion on modeling and types of possible sensor faults in the power electronics voltage and current sensors can be found in [19] and [4] that may occur at dc voltage and ac current sensors.…”

“…Consequently, the GSC operation can be critically affected, which can either trip the protection mechanisms or downgrade the reliability and power quality of the GSC [3]. Specifically, in the Hall effect-based voltage and current sensors, the malfunction mechanism can be attributed to either the failure of the integrated circuit of an operational amplifier, the failure of electronic components (resistors or capacitors), or cosmic radiation, which may cause gradual or single-event burnout of the sensor [4]. The aforementioned failure mechanism of voltage and current sensors can lead to catastrophic failure of the GSC and can trip the protection relay of RES.…”