Energy storage devices are required for power balance and power quality in stand alone wind energy systems. A Vanadium Redox Flow Battery (VRB) system has many features which make its integration with a standalone wind energy system attractive. This paper proposes the integration of a VRB system with a typical stand-alone wind energy system during wind speed variation as well as transient performance under variable load. The investigated system consists of a variable speed wind turbine with permanent magnet synchronous generator (PMSG), diode rectifier bridge, buck-boost converter, bidirectional charge controller, transformer, inverter, ac loads and VRB (to store a surplus of wind energy and to supply power during a wind power shortage). The main purpose is to supply domestic appliances through a single phase 230V, 50Hz inverter. Simulations are accomplished in order to validate the stability of the supply. Figure 1. A vanadium redox flow battery I.

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Introduction: Faculty members have little time and usually lack expertise to provide writing feedback on lab reports. Sending students to a writing center, an existing resource on virtually all college campuses, could fill that gap. However, the majority of peer writing tutors are in nontechnical majors, and little research exists on training them to provide support for engineering students. Research question: Can peer writing tutors without technical backgrounds be trained to provide effective feedback to engineering students? About the case: Previously, sending students to the writing center was ineffective. The students did not see the value and the tutors did not feel capable of providing feedback to them. To remedy this situation, an interdisciplinary training method was developed collaboratively by an engineering professor and the writing center director. Situating the case: Researchers have suggested that it is

This paper presents the results of a novel digital signal processor (DSP) based technique for signal conditioning of Linear Variable Dgferential Transformers (L VDTs).Signal conditioning is achieved through a modified DSP-based Costas receiver. This system is tested and compared with two commercially available analog signal conditioners and a second DSP-based signal conditioner. The system developed by the authors has better dynamic response than existing solutions and better noise rejection than commercially available solutions. Static testing of the system using both 4-wire and 5-wire LVDTs verifies that the conditioner meets or exceeds the linearity performance of existing signal conditioning systems over the full-scale operating range. In addition, this system requires no phase compensation network or manual tuning.

This paper introduces a new configuration of the DFIG-based wind energy conversion system (WECS) employing only a reduced-size Rotor Side Converter (RSC) in tandem with a supercapacitor. In the proposed structure, the Grid Side Converter (GSC) utilized in conventional DFIG-based WECSs is successfully eliminated. This is accomplished by employing the hydraulic transmission system (HTS) as a continuously variable and shaft decoupling transmission unit. This transforms the conventional constant-ratio drives by providing an opportunity to control the power flow through the generator's rotor circuit regardless of the wind turbine's shaft speed. This feature of HTS can be utilized to control the RSC power and ultimately regulate the supercapacitor voltage without a need for GSC. The proposed system is investigated and simulated in MATLAB Simulink at various wind speeds to validate the results and demonstrate the dynamic performance of the system.

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