Innovative Adaptive Protection Approach to Maximize the Security and Performance of Phase/Earth Overcurrent Relay for Microgrid Considering Earth Fault Scenarios.

Highly Fast Innovative Overcurrent Protection Scheme for Microgrid Using Metaheuristic Optimization Algorithms and Nonstandard Tripping Characteristics

“…The increasing of DGs in the distribution networks make the OC relays coordination an increasingly complex problem. Recently, various researchers have presented the nonstandard curve characteristics as a potential solution for the protection coordination problem in microgrid [17], [18] and using the metaheuristic optimization algorithms [19]. In [12] and [20], the OC coordination problem described as objective function with several constraints and they used the GA method to achieve the minimum operation time for the relays by finding the optimal settings for the OC relays.…”

“…Therefore, the Plug Setting Multiplier (PSM) is selected within the maximum and minimum limitations based on the fault current level seen by the relay (maximum and minimum) and the load level as light load or overload. In general, the PSM limits start from 1.1 to 20 times of PSM for OC relays in industrial and microgrid applications [4], [7], [19]. In this paper, the PSM limits vary between 1.1 and 100, where the PMS has been extended to 100 instead of 20 times of PSM to cover the different increases in the DGs and fault current levels in the microgrid.…”

“…In addition, the fault characteristics (level, location and direction) are different for a power network connected to DGs compared to the traditional network without DGs. This limitation will decrease the sensitivity of OC protection systems in the modern network and microgrid system, where are a wide range of the minimum and maximum fault current levels [7]- [9], [19]. To improve the OC protection system performance and overcome the NI characteristic limitation in the microgrid system, this work proposed an advanced optimal OC relays coordination scheme based on modern metaheuristic optimization algorithms and using a nonstandard tripping characteristic.…”

“…Then, the 𝑂𝐹 𝑟𝑒𝑙𝑎𝑦𝑠 , in Equation 4, will be solved by using four modern metaheuristic optimization algorithms (MPSO, TL, GWO and MFO) to find the optimal TMS for OC relays based on standard and nonstandard curves. In the literature, the MPSO [28], [29], TL [19], [30], GWO [1], [31] and MFO [1], [32] algorithms showed a powerful performance in solving complex engineering problems and stochastic behaviour by considering a different number of possible solutions at each iteration [1], [7], [19]. Therefore, these modern metaheuristic optimization algorithms can be beneficial in improving the OC relays performance and solving the relays coordination problems in a microgrid.…”

“…The current literature has begun to investigate the benefits of solving different engineering problems as optimization problems by using new optimization algorithms and treating the challenges of adding renewable energy sources to the power network. In this paper, the modern optimization algorithms MPSO [29], TL [19], [30], GWO [31] and MFO [32] are adapted and employed to solve OC relays coordination problem and handle the stochastic nature of fault currents and load levels in the power network due to connecting the DGs. The newly proposed optimization algorithms are designed and developed to solve complex optimization problems most simply within a low computational cost.…”