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This paper proposes a single-phase nine-level (9L) inverter topology suitable for control strategy and design of an AC/DC/AC IGBT-PMW power converter for PMSG-based variable-speed wind energy conversion systems (VSWECS) operation in grid/load-connected mode are presented. VSWECS consists of a PMSG connected to a AC-DC IGBT-based PWM rectifier and a DC/AC IGBT-based PWM inverter with LCL filter. The proposed inverter is realized using a T-type neutral point-clamped inverter connected in cascade to a oating capacitor (FC) H-bridge. Additionally, two low-frequency switches are added across the dc-link enabling the inverter to generate a 9L waveform. A sensor less voltage control based on redundant switching state is developed and embedded with PWM controller, which is responsible for regulating the FC voltage at one quarter of the dc source voltage. The proposed PWM technique employs the generation of 9L waveform without using any voltage sensor, thereby reducing the complexity of the overall control scheme. This, in turn, will make the overall system appealing for various industrial applications. In comparison to conventional and recent topologies, generation of the 9L waveform using a lower number of components is the notable contribution. Another important feature of the proposed inverter is that if FC H-bridge fails, it can be bypassed, and the inverter can still operate as a 5L inverter at its nominal power rating. Furthermore, a comprehensive comparison study is included which confirms the merits of the proposed inverter against those of other state-of-the art topologies. Finally, simulation and hardware results are included for validating the feasibility of the proposed system. [ABSTRACT FROM AUTHOR]

Unified Power Quality Conditioner (UPQC) device combines a shunt active filter together with a series active filter in a back-to-back configuration, to simultaneously compensate the supply voltage and the load current. The Three phase four wire system is realized from a three phase three wire system. In three phases, four wire system electrical loads are connected from line to neutral of the three phases. Neutral current in three-phase power systems is often thought to be only the result of the imbalance of the phase currents. Unbalance is a serious power quality problem, mainly affecting low-voltage distribution systems, as for instance encountered in office buildings with abundant PCs and lighting. In an ideal balanced sinusoidal three-phase power system, the neutral current is the vector sum of the three phase currents, should be equal to zero. Under normal operating condition, some phase unbalance occurs resulting in a small neutral current. A new control strategy to balance the unbalanced load currents is presented. The neutral current that may ow towards transformer neutral point is compensated by using a four-leg voltage source inverter topology in shunt part of the inverter. Hysteresis controller is mainly used to control the gating pulses of the inverter. The series transformer neutral will be at virtual zero potential during all operating conditions. The simulation results based on MAT-LAB/Simulink are presented to show the effectiveness of the proposed UPQC-based three phases four wire distribution system. [ABSTRACT FROM AUTHOR]

Lack of resources established in the present world is initiating everyone towards energy efficient technologies. Among all these resources, power is one which needs to be monitored and controlled as per the need since electricity consumption is increasing day-by day. In this project, we have described an effective implementation of an intelligent remote monitoring system for solar Photovoltaic (PV), Wind Energy Conversion System (WECS) and battery which are used in a greenhouse environment. The proposed system design can be installed in solar PV, WECS and battery in order to solve management problems, maintenance and shortens the mean time to repair. We have designed a smart remote monitoring system based on internet of thing for monitoring Solar PV, WECS and Battery. This system had incorporated remote monitoring for solar PV, WECS and battery through internet using host, network GPRS (Global Positioning Radio Service), embedded system gateway and Arduino. The result of our demonstration shows that the system can monitor store and manipulate data from solar PV, WECS and battery. Thus, the remote monitoring functions are realized in real-time. [ABSTRACT FROM AUTHOR]

The power control of small-scale wind energy conversion system is usually limited by the sluggish mechanical dynamic. Aiming at highlighting this phenomenon, this article introduces a small-scale wind energy conversion system using the permanent magnet synchronous machine as generator to validate different combinations of control strategy resulting from four different maximum power point tracking (MPPT) methods with hysteresis control: one indirect MPPT method based on a look-up table and three direct methods based on perturb and observe relationship. Following two ideal wind speed profiles, a real rapid wind speed profile and using a test bench emulating a small-scale wind turbine, the MPPT methods are compared and analysed based on experimental results. The indirect method operates with the best MPPT performances for all three wind speed profiles while requiring accurate knowledge of the controlled system. The direct methods operate with low MPPT performance under rapid variation of wind speed and the superiority of variable step size is not significant since the dynamic process of the perturbation strongly weakens the effect of MPPT algorithm. In proposed system Adaptive Network-based Fuzzy Interference System is used to control the MPPT. [ABSTRACT FROM AUTHOR]