No abstract

No abstract

This paper suggests an adaptive control approach using water cycle algorithm optimization method (WCA) modified by a new technique called ''Balloon Effect''. The main concept of Balloon Effect is to increase the ability of the WCA to tune individually the gains of the controller online. The proposed technique has been used to tune the gains of PID controller and applied to control both of the load frequency control in micro-grid power system (which minimize the fundamental frequency variations) and the position of armature-controlled DC motor. Digital simulations have been carried out to prove the efficiency of the proposed adaptive controller-based WCA with Balloon Effect. The obtained results showed that the proposed adaptive controller maintains robust performance, and effectively reduces the impact of identified disturbances and uncertainties.

No abstract

This paper presents an adaptive protection scheme (APS) for solving the coordination problem that deals with coordination directional overcurrent relays (DOCRs) and distance relays second zone time, in relation to coordination with DOCRs. The coordination problem becomes more complex with the impact of renewable energy sources (RES) when added to the distribution grid. This leads to a change in the grid topology, caused by the on/off states of the distribution generators (DG). The frequency of topological changes in distribution grids poses a challenge to the power system’s protection components. The change in the state of DGs leads to malfunction in reliability and miscoordination between protection relays, since that causes a direct effect to the short circuit currents. This paper used the school-based optimization (SBO) algorithm, which simulates the educational process, in order to deal with coordination problems. That algorithm is modified (MSBO) by modified both learning and teaching processes. The IEEE 8-bus test system and IEEE 14-bus distribution network are used to validate the proposed coordination system’s effectiveness when dealing with the coordination process between distance and DOCRs, at both the near- and far-end in the typical topological grid and with DGs in working order.

This paper proposes an adaptive protection scheme (APS) based on the original heap-based optimization (HBO) and a modified HBO (MHBO). APS is used to solve protection relays coordination problems that include directional overcurrent relays (DOCRs) as well as the distance relay’s second zone times. The complexity of the coordination problem increases with the impact of distributed generators (DGs) switching (ON/OFF). Topological changes in grid configuration frequently occur in distributing networks, equipped with DGs, causing changes in the values and direction of short circuit currents. This issue becomes a challenge for protection systems to avoid relays miscoordination and save a network’s reliability. In the proposed MHBO, the Original HBO is modified by three points, population are divided into subgroups, then they are unified into one group gradually, those subgroups are exchanging some search agents between themselves, these search agents are called travelling agents, and the last one is about, upgrading an internal equation in the original algorithm. For validating the proposed relays coordination, the IEEE 8-bus test system, and the IEEE 14-bus distribution network are selected as case studies. The obtained simulated results of the proposed algorithm show better performance compared with those obtained by the previous algorithms.

No abstract

In this paper, an improved Bonobo optimization algorithm (IBO) is proposed to solve the optimal coordination of directional overcurrent relays (DOCRs) problem. This problem is important for power system protection. It is considered a nonlinear and highly constrained optimization problem. IBO aims to improve the performance of the original Bonobo optimization algorithm (BO) using Levy flight distribution and three leaders selection. Both BO and IBO are utilized to develop two solvers for optimal coordination of DOCRs. The 15-bus and 30-bus test systems are used to validate BO and IBO in minimizing the total operating time of relays with satisfying the operational constraints. The results of the proposed IBO algorithm have been compared with the original BO algorithm and other well-known algorithms. The obtained results confirmed the effectiveness and superiority of the proposed IBO algorithm compared with the other algorithms in minimizing the total operating time of relays for the optimal coordination of DOCRs. Keywords: Directional overcurrent relays; Optimal coordination; Improved Bonobo algorithm; Levy flight distribution; Three leaders selection.