Wind turbine participation in micro‐grid frequency control through self‐tuning, adaptive fuzzy droop in de‐loaded area

Abstract The variations in the consumption load and generation power in microgrid systems such as photovoltaic, wind-turbine fuel cell and energy storage systems (PV/WT/FC/ESSs) has challenged the load-frequency control due to the increased complexity and nonlinear nature of these systems. This paper employs a self-tuning controller based on the fuzzy logic to overcome parameter uncertainties of classic controllers, such as operation conditions, the change in the operating point of the microgrid and the uncertainty of microgrid modeling. Further, a combined fuzzy logic and fractional-order controller is used for load-frequency control of the off-grid microgrid with the influence of renewable resources because the latter controller benefits robust performance and enjoys a flexible structure. To reach a better operation for the proposed controller, a novel meta-heuristic whale algorithm has been used to optimally determine the input and output scale coefficients of the fuzzy controller and fractional orders of the fractional-order controller. The suggested approach is applied to a microgrid with a diesel generator, wind turbine, photovoltaic systems, and energy storage devices. The comparison made between the results of the proposed controller and those of the classic PID controller proves the superiority of the optimized fractional-order self-tuning fuzzy controller in terms of operation characteristics, response speed, and the reduction in frequency deviations against load variations.

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Retaining of Frequency in Micro-grid with Wind Turbine and Diesel Generator

Engineering, Technology & Applied Science Research ◽

10.48084/etasr.2413 ◽

2018 ◽

Vol 8 (6) ◽

pp. 3646-3651

Author(s):

P. D. Chung

Keyword(s):

Power Control ◽

Wind Turbine ◽

Control Method ◽

Frequency Control ◽

Speed Control ◽

Frequency Regulation ◽

Rotor Speed ◽

Diesel Generator ◽

Control Scheme ◽

Micro Grid

This paper aims to compare the performance of frequency regulation with two control modes of controller including power control scheme and rotor speed control scheme. The frequency control in this research is based on the frequency droop control method but fuzzy logic is used to define the frequency droop coefficient. To compare the performance of these control modes, a simulation of a micro-grid with the existence of a group of doubly fed induction generator wind turbine system and a diesel generator is fulfilled in Matlab/Simulink. Simulation results indicated that the frequency in the micro-grid with two control schemes always remains in the operation range. With the power control scheme, the frequency in the micro-grid is smoother than that with the rotor speed control. Additionally, DFIG wind turbine with the power control scheme has a better performance in terms of electrical energy when compared to the rotor speed control scheme, and hence the cost of fuel used by diesel is less costly.

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Frequency Control in a Micro Grid with Wind Turbine System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.433-440.1116 ◽

2012 ◽

Vol 433-440 ◽

pp. 1116-1120

Author(s):

Amir Jalali Shahrood ◽

S.M. Moghaddas Tafreshi ◽

A. Houshmand Viky ◽

Azim Saliminiaie Lahiji ◽

Milad Moghassem Hamidi

Keyword(s):

Wind Turbine ◽

Power Flow ◽

Frequency Control ◽

Wind Turbine System ◽

Pi Controllers ◽

Micro Grid ◽

Micro Turbine ◽

Trial And Error Method ◽

System Frequency ◽

Ultra Capacitor

In this paper a micro grid that consists of micro turbine, fuel cell, wind turbine, electrolyzer, ultra capacitor and battery, is analyzed for frequency control, during several load disturbances. In other word, produced power from all the other distributed generation (DG) sources are regulated by PI controllers. As the balance between the load and generation changes, the power system frequency deviates. In order to reduce these frequency deviations, the PI controllers, used to regulate the power flow from DGs. It is proposed that, proportional and integral gains tuned through trial and error method.

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