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Integration of renewable energies such as wind and solar with an energy storage system (ESS) in a distribution network is the interest of current studies in power system engineering. Wind and battery ESS (BESS) are known for their complement and efficient approaches into the distribution networks. The promising of renewable energies for wind and solar in Afghanistan is a motivation for stepping up the power sector of the country by enhancing the power quality as well as self‐dependency in electricity production. In this study, a multi‐objective optimisation technique, non‐dominated sorting genetic algorithm II (NSGA‐II) is proposed for an extensive distribution network in Kabul city considering technical, environmental, and financial control schemes for the network improvement. Three different scenarios with various objective functions are deemed to evaluate their impact on decision variables and network parameters. Furthermore, optimum allocation of the wind turbine and charge/discharge scheduling of BESS are revealed with improvement in performance of the power system. Simulations are deployed in MATLAB® with its application on developed 162‐bus real‐distribution network to demonstrate the effect of different objective function arrangements in each scenario as well as confirming the robustness of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper presents a control approach for the Permanent Magnet Synchronous Generator (PMSG) based Wind Energy Conversion Systems (WECS) under a wide range of wind speeds. Generally, most of the wind turbines are turned-off and disconnected from the power grid, in case wind velocity is gone over 25 m/s. It may cause wind power supply shortage from wind farms. This research introduces a pitch angle controller as well as a rotational speed control system so that the PMSG based WECS can generate power if the wind speeds are above 25 m/s. The proposed method reduces the mechanical stress of the wind turbine by preferential reducing of the rotational speed rather than the mechanical torque during strong wind condition. As a result, the chance of turning-off the is reduced compared to the conventional control system because the PMSG based WECS can temporarily tolerate the wind speed up to 35 m/s. A 2 MW WECS with the electrical and mechanical characteristics is modeled in the MATLAB/SimPowerSystems ® to verify the proposed research. [ABSTRACT FROM AUTHOR]

Output power fluctuation of the wind turbine generator is a serious issue for power systems. The battery energy storage system is installed to the power system to solve this problem. However, the large battery energy storage system can increase the capital cost of the wind turbine generator system. Hence, the capacity of the battery should be reduced as much as possible. This article presents anH∞based control method for the output power smoothing method of the wind turbine generator by using a battery energy storage system. The output power fluctuation of the wind turbine generator is considered in the frequency domain. Low-frequency fluctuations are smoothed by pitch angle control of the wind turbine generator, while high-frequency variations are smoothed by charge or discharge of the battery energy storage system, respectively. The battery energy storage system’s capacity and mechanical stress of wind turbine blades can be reduced by the proposed method. In addition, the gain-scheduled control theory is applied to the pitch angle control system of the wind turbine generator. Therefore, the robust control performance for high non-linearities of the wind turbine generator model can be achieved. The effectiveness of the proposed method is validated by numerical simulations. [ABSTRACT FROM AUTHOR]

This paper presents a power smoothing control scheme for a permanent-magnet-synchronous-generator-based wind farm considering wake effects. The integrated power smoothing method consists of a pitch angle control system, a kinetic wind-energy turbine inertia control system, and a dc-link voltage control system. Low frequency range power fluctuations caused by wind speed variations are smoothed by the pitch angle control system and the kinetic wind-energy turbine inertia control system. Power fluctuations in the high frequency range are smoothed by the dc-link voltage control system. This power smoothing approach is cost-effective because the power smoothing is made possible without additional energy storage devices. In addition, the wake effects of the wind farm are considered for power smoothing with different tower spaces. The proposed method is compared with the conventional maximum-power-point-tracking method. Simulation results confirm the proposed method efficacy in smoothing the power injected by a wind farm. [ABSTRACT FROM PUBLISHER]

To incorporate the abundance of renewable energy into the power system, it is required to reconfigure the energy system. An intelligent power grid such as the smart grid is the solution for future energy demand. Among several renewable sources, the wind energy conversion system (WECS) is the rapidly growing source of energy, which is considered as the backbone of renewable energy and the smart grid. This paper deals with control strategies of distributed wind farms that are connected to smart houses for a smart grid application. A grid-side energy storage system is considered to deliver smooth power to the system. Stable control strategies under the line fault condition are also discussed in this paper. The surplus power of the smart houses is sent back to the power grid, and a house owner can benefit by selling the extra power to the power company. The detailed modeling and control strategies of an intelligent power system are demonstrated in this paper. The effectiveness of the proposed system is verified by the extensive numerical simulation results. [ABSTRACT FROM AUTHOR]

ABSTRACT This paper concentrates on the output power smoothing and the grid dynamic response enhancement of a grid-interactive MW-class permanent magnet synchronous generator-based wind energy conversion system (WECS). A simple fuzzy controller method is applied to improve the overall performance of the WECS. The proposed method can retrieve the storing kinetic energy from the inertia of a wind turbine, perfectly. As a result, it can ensure a proficient power smoothing of the variable speed WECS. On the other hand, the grid side inverter is controlled by the fuzzy controller. This approach can reduce the fluctuation of DC link voltage and can deliver a smooth power to the power grid. The proposed method is compared with two other methods such as the maximum power point tracking control method and the without fuzzy controller method. A simple shunt circuit also includes in the DC link circuit. Therefore, during the system fault condition, the WECS can perform a stable operation. Effectiveness of the proposed method is verified by numerical simulations. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Highlights: [•] A robust controller based frequency control method is designed for a small power plant. [•] The controller design procedures are explained elaborately. [•] The small power plant consists of a wind turbine, a battery storage and a diesel generator. [•] The proposed method can reduce the size of a battery storage system. [•] The proposed method can reduce the frequency deviations, and blades stress. [ABSTRACT FROM AUTHOR]

This paper deals with controlling the output power smoothing of a wind energy conversion systems (WECS) by using permanent magnet synchronous generator (PMSG). It uses the inertia control of the wind turbine and DC-link voltage control. The PMSG is connected to the grid through a generator-side converter and a grid-side inverter based on AC-DC-AC methods. The generator-side converter is used to control the torque of the PMSG while the grid-side inverter is used to control DC-Link voltage and grid voltage. Fuzzy logic is implemented to determine the torque command by using inertia of wind turbine. The inputs of the fuzzy logic are given by the operating point of the rotational speed of the PMSG and the difference between the wind turbine torque and the generator torque. From the proposed method, the generator torque is smoothed and kinetic energy generated by the inertia of the wind turbine is used to smooth the power fluctuations of PMSG. Also, a stable operation of WECS is achieved during the system fault by using the chopper circuit in the DC-link circuit. The output power smoothing is achieved with stability and low cost. The effectiveness of the proposed method is verified by the numerical simulations. [ABSTRACT FROM AUTHOR]

In this article, a technique is proposed for maximum power-point tracking control of a wind generation system. The optimal operation speed to which the wind turbine output power maximizes is determined with parameters identified by an iterative least squares technique. The effectiveness of the maximum point tracking control with identified parameters of wind turbine is verified by computer simulation. In addition, the article discusses how to address rotational speed and output power in the case when the wind turbine parameters used for determining the optimum rotational speed have errors. [ABSTRACT FROM AUTHOR]

Wind energy conversion systems have become important in the research of renewable energy sources. This is in no small part due to the rapid advances in the size of wind generators as well as the development of power electronics and their applicability in wind energy extraction. However, wind energy has a drawback of having only 1/800 (gm per cubic cm) density as compared to that of water energy. Wind energy does not remain constant and wind turbine output is proportional to the cube of wind speed, which causes the generated power of the wind turbine generator (WTG) to fluctuate. In this paper, a technique is proposed for output power leveling of a wind generation system. Wind turbine blades have a large inertia compared to the inertia of a generator. The inertia of the rotor behaves like an inductor in an electrical circuit. It helps smooth the wind turbine output power, stores energy during acceleration, and restores energy during deceleration. The effectiveness of output power leveling control is verified by simulations for the wind power generation system. [ABSTRACT FROM AUTHOR]