Engineering Commons^™

Enhanced Control Algorithms In Permanent Magnet Synchronous Machines, Haibo Li

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Permanent magnet synchronous machines (PMSMs) are gaining increasing popularity in various applications due to their advantages, such as high efficiency, high power density, and superior control performance. A well-designed machine control algorithm is indispensable for a PMSM system to secure its good performance.

In this work, enhanced control algorithms in PMSMs are developed. Online machine current trajectory tracking, source power management, hardware overcurrent regulation, and machine current sensor fault detection and isolation (FDI) are included in the developed algorithms. The online machine current trajectory tracking ensures the maximum torque per ampere (MTPA) or maximum torque per voltage (MTPV) control in …

Low Latency Bearing Fault Detection Of Direct-Drive Wind Turbines Using Stator Current, Samrat Nath, Jingxian Wu, Yue Zhao, Wei Qiao

Department of Electrical and Computer Engineering: Faculty Publications

Low latency change detection aims to minimize the detection delay of an abrupt change in probability distributions of a random process, subject to certain performance constraints such as the probability of false alarm (PFA). In this paper, we study the low latency detection of bearing faults of direct-drive wind turbines (WT), by analyzing the statistical behaviors of stator currents generated by the WT in real-time. It is discovered that the presence of fault will affect the statistical distribution of WT stator current amplitude at certain frequencies. Since the signature of a fault can appear in one of the multiple possible …

Current-Based Fault Detection For Wind Turbine Systems Via Hilbert-Huang Transform, Dingguo Lu, Wei Qiao, Xiang Gong, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

Mechanical failures of wind turbines represent a significant cost in both repairs and downtime. Detecting incipient faults of wind turbine components permits maintenance to be scheduled and failed parts to be repaired or replaced before causing failures of other components or catastrophic failure of the system. This paper proposes a Hilbert-Huang transform (HHT)-based algorithm to effectively extract fault signatures in generator current signals for wind turbine fault diagnosis by using the HHT’s capability of accurately representing the instantaneous amplitude and frequency of nonlinear and nonstationary signals. A phase-lock-loop (PLL) method is integrated to estimate wind turbine rotating speed, which is …

Online Nonintrusive Condition Monitoring And Fault Detection For Wind Turbines, Xiang Gong

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

The goal of this dissertation research is to develop online nonintrusive condition monitoring and fault detection methods for wind turbine generators (WTGs). The proposed methods use only the current measurements that have already been used by the control and protection systems of WTGs; no additional sensors or data acquisition devices are needed. Current-based condition monitoring and fault detection techniques have great economic benefits and the potential to be adopted by the wind energy industry. However, there are challenges in using current measurements for wind turbine condition monitoring and fault detection. First, it is a challenge to extract WTG fault signatures …

Imbalance Fault Detection Of Direct-Drive Wind Turbines Using Generator Current Signals, Xiang Gong, Wei Qiao

Department of Electrical and Computer Engineering: Faculty Publications

Imbalance faults constitute a significant portion of all faults in wind turbine generators (WTGs). WTG imbalance fault detection using generator current measurements has advantages over traditional vibration-based methods in terms of cost, implementation, and system reliability. However, there are challenges in using current signals for imbalance fault detection due to low signal-to-noise ratio of the useful information in current signals and non-stationary characteristic frequencies of imbalance faults. This paper proposes a method of using generator stator currents for imbalance fault detection of direct-drive WTGs. In the proposed method, the variable shaft rotating frequency of a WTG is estimated from one …