Engineering
Ebadollah Amouzad Mahdiraji; Mojtaba Sedghi Amiri
Abstract
Nowadays, to involve wind turbines in controlling the network frequency, drop and inertia control methods are usually used for variable speed wind turbines. Adjusting the benefits of droop and inertia control loops is very effective on the performance of wind turbines, but due to the variability of wind ...
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Nowadays, to involve wind turbines in controlling the network frequency, drop and inertia control methods are usually used for variable speed wind turbines. Adjusting the benefits of droop and inertia control loops is very effective on the performance of wind turbines, but due to the variability of wind speed and network conditions, adjusting the control coefficients that produce the best response in all conditions is impossible. In this paper, a new method for the comparative regulation of the gain of the droplet control loops and the inertia of the doubly-fed induction generator (DFIG) is presented. Also, due to the relief of problems and shortcomings of wind turbine and network modeling, the use of a data-driven method, which operates only on the input and output of the system, has been proposed. In the new idea presented for faster control and prevention of sharp frequency droop, new equations have been calculated to update the coefficients of the control loops using the second fault derivative, which is used in the comparative adjustment of the gain of the droop and inertia control loops. In the proposed control method, the next instantaneous output is first estimated using KVNN and then the coefficients of the frequency control loops are adjusted adaptively using the Hessian matrix. The simulation results for a DFIG wind farm show the proper performance of an adaptive method based on data-driven control in increasing the minimum frequency and improving the network frequency in a permanent and transient state when a fault occurs.
Engineering
Mojtaba Sedghi Amiri; Ebadollah Amouzad Mahdiraji
Abstract
One of the most commonly used equipment in the power system, which is exposed to various types of faults for various reasons, is high and low voltage pressure cables. Due to the fact that cables, either power or distribution cables are mostly transported from underground, despite their further reliability ...
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One of the most commonly used equipment in the power system, which is exposed to various types of faults for various reasons, is high and low voltage pressure cables. Due to the fact that cables, either power or distribution cables are mostly transported from underground, despite their further reliability in airway, they are more difficult to repair and possibly replace in case of fault, in line with this the correct fault detection and location of them is of utmost important. In this paper, as is clear from the title of the research, the Fourier transform and Modal transform methods are used to find the type and location of faults, so that the efficiency of the selected method for detecting and locating the faults in underground transmission cables is examined and the speed and accuracy of finding a solution to the problem is assessed. In this paper, it is expected that the Fourier transform method, followed by the Modal transform has substantial speed and accuracy in determining the type and location of the faults. Meanwhile, the detection and location indicators are used to determine the type and location of the fault, which as shown in the simulations, will have efficient performance. The sample model is simulated to demonstrate the correctness of these methods. The simulation results from MATLAB and EMTP/ATP software confirm the precise and rapid performance of the proposed method.