Single Open-phase Fault Detection with Fault-Tolerant Control of an Inverter-fed Permanent Magnet Synchronous Machine

Abstract

In this paper first a current predictive method for single open-phase fault detection in a three phase drive with a permanent magnet synchronous machine is presented. The proposed method is based on a predictive stator current calculation. For each sampling interval the difference between the actual stator current and its predicted value in a previous sampling interval is calculated. To identify the location of a single open-phase fault, an identification method is presented which is based on the analysis of the stator current vector angle. After the single open-phase fault is detected and identified it is desirable for the electrical machine to continue operating with a reduced number of phases. For this purpose, a modified direct torque control algorithm for the fault-tolerant control is implemented. In order to improve the performance of the drive, a pre-firing angle is additionally introduced. All proposed methods have been simulated in Matlab/Simulink and verified on an experimental model. Detekcija odspojene faze i na kvarove otporno upravljanje pretvaračem napajanim sinkronim motorom s permanentnim magnetima. Učlanku je prvo predstavljena metoda za detekciju kvara odspojene faze u trofaznom elektromotornom pogonu sa sinkronim motorom s permanentim magnetima zasnovana na predikciji struja statora. U svakom koraku uzorkovanja računa se razlika izmeu trenutne mjerene struje statora i prediktirane vrijednosti iz prethodnog koraka. U svrhu odreivanja lokacije odspojene faze, predstavljena je metoda identifikacije zasnovana na analizi kuta vektora struje statora. Nakon otkrivene i utvrene odspojene faze, poželjno je nastaviti rad električnog stroja sa smanjenim brojem faza. U ovu svrhu implementiran je izmijenjeni algoritam izravnog upravljanja momentom za postizanje na kvarove otpornog upravljanja. Da bi se unaprijedilo vladanje sustava elektromotornog pogona, dodatno je uveden kut prethoenja aktivacije impulsa. Sve predložene metode simulirane su u Matlab/Simulink okruženju i provjerene na eksperimentalnom postavu.Ključne riječi: Sinkroni motor s permanentnim magnetima, na kvarove otporan sustav, kvar jedne odspojene faze, na kvarove otporno upravljanje, kut prethoenja aktivacije impulsa

Cost-Effective Three-Phase PMSM Drive Tolerant to Open-Phase Fault

“…This can be done using different methods, e.g. by analyzing the angle of the stator current vector [21]. The method is based upon the fact that when one phase is disconnected, the angle of stator current vector can only take two discrete values.…”

“…Thus the machine is operating in a single phase mode optimized through "prefiring" to gain highest possible torque. In addition to [21], the analysis of the post-fault torque de-rating caused by the fourswitch operation is given.…”

“…Instead of using much simpler direct torque control (DTC) as in [21], the detection algorithm for field oriented control (FOC) based on current estimation (similar to [13]) is analyzed. Besides, the threshold level for fault detection is also analytically determined in this paper.…”

Application of Open-Circuit IGBT Faults Diagnostic Method in DTC-SVM Induction Motor Drive

“…This approach is effective but requires more complex computing. A similar technique is presented in [13], where for an open-phase fault diagnosis, an error between the predicted and measured stator current is used. This method is effective but it requires detailed motor parameters identification for the current prediction.…”

“…Thus the most frequently developed approaches are based on the analysis of easily accessible signals of the control structures, such as measured currents or estimated voltages. Many of them rely on monitoring of standardized errors between reference, estimated or measured diagnostic variables [8]- [13]. In [8] diagnostic signals are defined as average values of the errors between reference and measured phase currents that are normalized by the module of the measured current vector.…”