Load-frequency control by hybrid evolutionary fuzzy PI controller

AbstractThis paper proposes a load frequency control (LFC) scheme for the distributed generation (DG) system of the microgrid (μ-grid) using the D-partition method (DPM). μ-grid is formed with a combination of renewable and non-renewable sources to supply distribution system loads of smaller capacity. In this research paper, μ-grid comprising of a combination of a wind turbine generator (WTG) and Diesel Generator (DG) are taken for investigation of LFC. For the effective control of real power generation of μ-grid, Proportional-integral (PI) controllers are implemented for WTG and DG system so that the frequency deviation is minimized. The PI controller parameters found by using DPM are compared with the conventional Ziegler-Nichols method (ZNM). The main contribution of this work is to provide a single step /simplistic computing method for calculating the PI controller parameters of a dynamic system such as the microgrid system comprising of the renewable energy sources without any further requirements of retuning. Simulation results demonstrate the robustness of the DPM, which is superior in damping frequency oscillations of μ-grid.

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STUDI ANALISIS GOVERNOR SEBAGAI LOAD FREQUENCY CONTROL PADA PLTG MENGGUNAKAN FUZZY LOGIC CONTROLLER

Majalah Ilmiah Teknologi Elektro ◽

10.24843/mite.2018.v17i01.p15 ◽

2018 ◽

Vol 17 (1) ◽

pp. 107

Author(s):

Gusti Made Ngurah Christy Aryanata ◽

I Nengah Suweden ◽

I Made Mataram

Keyword(s):

Fuzzy Logic ◽

Power System ◽

Fuzzy Logic Controller ◽

Frequency Control ◽

Pi Controller ◽

Active Power ◽

Load Frequency Control ◽

Electrical Power System ◽

Load Frequency ◽

Frequency Changes

A good electrical power system is a system that can serve the load in a sustainable and stable voltage and frequency. Changes in frequency occur due to the demand of loads that change from time to time. The frequency setting of the PLTG power system depends on the active power charge in the system. This active power setting is done by adjusting the magnitude of the generator drive coupling. The frequency setting is done by increasing and decreasing the amount of primary energy (fuel) and carried on the governor. Simulation in governor analysis study as load frequency control at PLTG using fuzzy logic controller is done by giving four types of cultivation that is 0,1 pu, 0,2pu, 0,3 pu and 0,4 pu. The simulation is done to compare the dynamic frequency response output and the resulting stability time using fuzzy logic controller with PI controller. Based on the results of comparative analysis conducted to prove that governor as load frequency control using fuzzy logic control is better than using PI controller. This can be seen from the output response frequency and time stability.

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A New Method for Computing the Delay Margin for the Stability of Load Frequency Control Systems

Energies ◽

10.3390/en11123460 ◽

2018 ◽

Vol 11 (12) ◽

pp. 3460 ◽

Cited By ~ 8

Author(s):

Ashraf Khalil ◽

Ang Swee Peng

Keyword(s):

Time Delay ◽

Power Systems ◽

Control Systems ◽

Frequency Control ◽

Pi Controller ◽

Load Frequency Control ◽

New Method ◽

Load Frequency ◽

The Stability ◽

Delay Margin

Open communication is an exigent need for future power systems, where time delay is unavoidable. In order to secure the stability of the grid, the frequency must remain within its limited range which is achieved through the load frequency control. Load frequency control signals are transmitted through communication networks which induce time delays that could destabilize power systems. So, in order to guarantee stability, the delay margin should be computed. In this paper, we present a new method for calculating the delay margin in load frequency control systems. The transcendental time delay characteristics equation is transformed into a frequency dependent equation. The spectral radius was used to find the frequencies at which the root crosses the imaginary axis. The crossing frequencies were determined through the sweeping test and the binary iteration algorithm. A one-area load frequency control system was chosen as a case study. The effectiveness of the proposed method was proven through comparison with the most recent published methods. The method shows its merit with less conservativeness and less computations. The impact of the proportional integral (PI) controller gains on the delay margin was investigated. It was found that increasing the PI controller gains reduces the delay margin.

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