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The recent environmental crisis and global warming have compelled an energy transition, particularly in the power generation and transportation sectors. Increased energy competence and production will necessitate enormous efforts. Admittedly, power system inertia metrics have revealed reduced inertia attributes, which could lead to a catastrophic shutdown and security issues in future electrical power systems. The design of the load frequency controller is essential for improving frequency regulation and power system stability. Nonetheless, more research is needed into control development and design approaches that take into account renewable energy characteristics, complexities, connected electric vehicles (EVs), and uncertainties. Metaheuristic‐based design methods and fractional order control have recently demonstrated an improved response when compared to classical design methods and integer‐order controllers. This work presents an improved fractional order hybrid control system based on two modified versions of the Manta Ray Foraging Optimization (MRFO) Algorithm. The exploration and exploitation stages of the modified MRFO are enhanced by utilizing a chaotic map and a weighting factor. The transients and steady‐state performance of the studied two‐areas interconnected microgrids have been significantly improved by incorporating the advantages of both the suggested fractional order‐based control approach and the proposed modified MRFO algorithms. While assessing the feasibility of the developed controller and modified optimizers, uncertainty, renewable energy fluctuations, load transients, and electric vehicle attributes are all properly considered. The modified MRFO's performances are evaluated using 23 benchmark functions, and the results are compared to the original MRFO and recent well‐known optimization algorithms. Both statistical analysis and time‐domain results demonstrate the superiority of the proposed modified optimizers and the proposed load frequency controller. [ABSTRACT FROM AUTHOR]

Coordination between protection and control devices is crucial for maintaining continuous operation of power systems. Existing strategies suffer from improper coordination of control and protection devices. Moreover, high penetration levels of renewable energy sources result in lowering the overall power system inertia. Therefore, this paper presents a robust fuzzy‐logic control (FLC) method for superconducting magnetic energy storage (SMES) in low inertia power systems. The new proposed FLC enables robust and wide operating range for SMES compared to the widely employed controllers. The proposed FLC method and load frequency control are coordinated to emulate virtual inertia. In addition, a cooperate coordination between frequency relay and proposed controller is preserved to maintain reliable operation of low inertia power systems. To prove the effectiveness of proposed coordination strategy, it has been tested with considering different load and renewable energy sources (RESs) disturbances with varying inertia level of the selected case study. The results demonstrate that the proposed FLC method can achieve robust SMES operation as virtual inertia controller (VIC) at wide operating range. Moreover, cooperative operation of VIC and frequency protection is preserved using the proposed coordination strategy. The power system availability, frequency regulation, and dynamic stability are improved using the proposed method. [ABSTRACT FROM AUTHOR]

Research concerns have grown towards precede diagnosis and prognosis of faults in power converters that result from thermal overheating problems of semiconductor devices. These problems directly affect the overall system availability and reliability as well. Many papers in the literature have addressed these problems. However, almost all of them suffer from major challenges such as increased components count, reduced output current ratings, reduced output voltage levels, and unbalanced voltages over the DC-link capacitors. These challenges impede the maximum energy harvesting, especially in renewable energy systems. A novel space vector modulation (SVM) algorithm has been proposed for lifetime prolongation of thermally aged power semiconductor devices in multilevel inverters. The proposed SVM algorithm functions to alleviate the affected device and to prevent the harmful consequences such as short-open circuit faults. The feasibility of the proposed method has been verified by simulation and experimental results on the three-phase three-level T-type inverter and compared with the previously addressed approaches. It can be concluded that the proposed algorithm provides a significant reduction of thermal stresses on the thermally aged power devices in addition to maintaining the same components count, the same output ratings, the same output levels, and balanced capacitors' voltages as well. [ABSTRACT FROM AUTHOR]

As promising and suitable candidates for high-power applications, multilevel inverters have become one of the most promising solutions in various applications. However, power switching devices are highly subjected to thermal overheating, which leads to shortened lifetime and reduced reliability. Thermal overheating may result from the degradation of power switching devices due to continuous overloading and power cycling. In addition, degradation and faults in the cooling system of power switching devices may cause thermal stresses as well. A new overheating-tolerant space vector modulation algorithm is proposed in this paper to alleviate thermal stresses from overheated power switching device. The proposed algorithm relies on using the redundancy property between switching states in multilevel inverters to continuously evaluate a cost function of the junction temperature of the overheated device for all possible switching sequence sets and then selects the optimal switching sequence. In addition, the proposed algorithm preserves the DC-link capacitor voltage without reduction in the output current of the inverter. The proposed algorithm is general, which can be applied to n-level inverters. Both simulation and experimental results reveal the efficient performance of the proposed algorithm using a three-level T-type inverter as a case study. Accordingly, the lifetime and reliability of the inverter are enhanced considerably using the proposed algorithm. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]