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The increased penetration of photovoltaic (PV) systems in different applications with critical loads such as in medical applications, industrial control systems, and telecommunications has highlighted pressing needs to address reliability and service continuity. Recently, distributed maximum power point tracking architectures, based on dc–dc converters, are being used increasingly in PV systems. Nevertheless, dc–dc converters are one of the important failure sources in a PV system. Since the semiconductor switches are one of the most critical elements in these converters, a fast switch fault detection method (FDM) is a mandatory step to guarantee the service continuity of these systems. This paper proposes a very fast FDM based on the shape of the inductor current associated to fault-tolerant (FT) operation for boost converter used in PV systems. By implementing fault diagnosis and reconfiguration strategies on a single field-programmable gate array target, both types of switch failure (open- and short-circuit faults) can be detected, identified and handled in real time. The FDM uses the signal provided by the current sensor dedicated to the control of the system. Consequently, no additional sensor is required. The proposed FT topology is based on a redundant switch. The results of hardware-in-the-loop and experimental tests, which all confirm the excellent performances of the proposed approach, are presented and discussed. The obtained results show that a switch fault can be detected in less than one switching period, typically around 100 ms in medium power applications, by the proposed FDM. [ABSTRACT FROM PUBLISHER]

In this paper, an FPGA-based fault-tolerant back-to-back converter without redundancy is studied. Before fault occurrence, the fault-tolerant converter operates like a conventional back-to-back six-leg converter, and after the fault, it becomes a five-leg converter. Design, implementation, and experimental verification of an FPGA-based reconfigurable control strategy for this converter are discussed. This reconfigurable control strategy allows the continuous operation of the converter with minimum affection from a fault in one of the semiconductor switches. A very fast detection scheme is used to detect and locate the fault. Implementation of the fault detection and of the fully digital control schemes on a single FPGA is realized, based on a suited methodology for rapid prototyping. FPGA in loop and also experimental tests are carried out, and the results are presented. These results confirm the capability of the proposed reconfigurable control and fault-tolerant structure. [ABSTRACT FROM PUBLISHER]

Fast fault detection and reconfiguration of power converters is necessary in electrical drives to prevent further damage and to make the continuity of service possible. On the other hand, component minimized converters may provide the benefits of higher reliability and less volume and cost. In this paper, a new fault-tolerant converter topology is studied. This converter has five legs before the fault occurrence, and after fault detection the converter continues to function with four legs. A very fast fault detection and reconfiguration scheme is presented and studied. Simulations and experimental tests are performed to evaluate the structure requirements, the digital reconfigurable controller, and fault detection scheme. For experimental tests, the control and the fault detection and reconfiguration schemes are implemented on a single field-programmable gate array (FPGA) chip. Experimental and simulation results show the effectiveness of the proposed fault-tolerant topology and its FPGA-based control. [ABSTRACT FROM PUBLISHER]

The performances of wind energy conversion systems (WECS) heavily depend on the accurate current sensing. A sudden failure in one of the current sensors decreases the system performances. Moreover, if a fault is not detected and handled quickly, its effect leads to system disconnection. Hence, to reduce the failure rate and to prevent unscheduled shutdown, a real-time fault detection, isolation, and compensation scheme could be adopted. This paper introduces a new field-programmable-gatearray (FPGA)-based grid-side-converter current sensor fault-tolerant control for WECS with doubly fed induction generator. The proposed current sensor fault detection is achieved by a predictive model. "FPGA-in-the-loop" and experimental results validate the effectiveness and satisfactory performances of the proposed method. [ABSTRACT FROM AUTHOR]

This paper discusses the design, implementation, experimental validation, and performances of a field-programmable gate array (FPGA)-based real-time power converter failure diagnosis for three-leg fault tolerant converter topologies used in wind energy conversion systems (WECSs). The developed approach minimizes the time interval between the fault occurrence and its diagnosis. We demonstrated the possibility to detect a faulty switch in less than 10 μs by using a diagnosis simultaneously based on a "time criterion" and a "voltage criterion." To attain such a short detection time, an FPGA fully digital implementation is used. The performances of the proposed FPGA -based fault detection method are evaluated for a new fault tolerant back-to-back converter topology suited for WECS with doubly fed induction generator (DFIG). We examine the failure diagnosis method and the response of the WECS when one of the power switches of the fault tolerant back-to-back converter is faulty. The experimental failure diagnosis implementation based on "FPGA in the loop" hardware prototyping verifies the performances of the fault tolerant WECS with DFIG. [ABSTRACT FROM AUTHOR]