FPGA Based Robust Open Transistor Fault Diagnosis and Fault Tolerant Sliding Mode Control of Five-Phase PM Motor Drives

Abstract

The voltage-source inverters (VSI) supplying a motor drive are prone to open transistor faults. To address this issue in faulttolerant drives applicable to electric vehicles, a new open transistor fault diagnosis (FD) method is presented in this paper. According to the proposed method, in order to define the FD index, the phase angle of the converter output current is estimated by a simple trigonometric function. The proposed FD method is adaptable, simple, capable of detecting multiple open switch faults and robust to load operational variations. Keeping the FD in mind as a mandatory part of the fault tolerant control algorithm, the FD block is applied to a five-phase converter supplying a multiphase fault-tolerant PM motor drive with nonsinusoidal unbalanced current waveforms. To investigate the performance of the FD technique, the fault-tolerant sliding mode control (SMC) of a five-phase brushless direct current (BLDC) motor is developed in this paper with the embedded FD block. Once the theory is explained, experimental waveforms are obtained from a five-phase BLDC motor to show the effectiveness of the proposed FD method. The FD algorithm is implemented on a field programmable gate array (FPGA).

Performance Evaluation of the Field-Oriented Control of Star-Connected 3-Phase Induction Motor Drives under Stator Winding Open-Circuit Faults

“…The only difference between (13) and a healthy 3-phase IM torque equation is that, in (13): M q =√3/2L ms , but in the healthy condition: M=3/2L ms . Moreover, the difference between (14) and a healthy 3-phase IM torque equation is that, in (14): √M d M q ≈1.14L ms , but in the healthy condition: M=3/2L ms . A comparison between the equations of the flux, speed and torque for healthy and faulty 3-phase IMs in the rotating reference frame based on the presented transformation matrices for stator current variables (equation (11) and (12)) is summarized in Table II (to obtain these equations the assumptions λ dr mr =|λ r | and λ qr mr =0 have been considered).…”

“…Despite the robustness of this method against disturbances, its performance under healthy conditions is not optimized. In active methods after fault detection and fault diagnosis, a new set of control parameters or a new control structure is applied [1]- [5] and [14]- [20]. These methods have good performances under both healthy and faulty conditions.…”

“…A large number of studies have been conducted on the implementation of vector control techniques for electrical machines under stator open-circuit faults [1]- [4] and [14]- [20]. Most of these works focused on developing vector control methods of faulty Permanent Magnet Synchronous Motors (PMSMs) and multi-phase IMs (five and six phase) [14]- [17].…”

“…Most of these works focused on developing vector control methods of faulty Permanent Magnet Synchronous Motors (PMSMs) and multi-phase IMs (five and six phase) [14]- [17]. In [18], [19] the analysis of star-connected 3-phase IMs in an open-phase fault indicates that the odd harmonic voltages of the magnitude and phase angle can be injected at the machine terminal to compensate torque pulsations.…”

Quick Diagnosis of Short Circuit Faults in Cascaded H-Bridge Multilevel Inverters using FPGA

“…Due to high performance of the Field-Programmable Gate Array (FPGA) in power electronics applications [20], some FPGA-based fault detection and reconfiguration methods have been suggested [21], [22]. Additionally, if both the fault detection and converter control units can be implemented on a single FPGA chip, the cost can be decreased [21].…”