Mohammed Haj-ahmed

• PhD
• Professor (Associate) at University of Jordan

In this paper, the particle swarm optimization (PSO) technique is used to optimally allocate phasor measurement units (PMUs) within standard test systems and a real-world power system. PMUs are allocated at system substations in a manner that ensures complete system observability while minimizing installation costs. This study considers IEEE 14-, 3...

University campuses resemble small cities in terms of their high energy use intensity. In transitioning toward sustainability, many universities have set ambitious targets to cover their electricity needs through solar energy. This has substantial environmental and economic advantages. Such initiatives bridge the gap between research and practice a...

In this paper, the robust features of wireless sensor networks are utilized in tele-protection systems. Cognitive radio algorithms are applied to transfer tripping signals from one substation to another in a permissive underreach transfer tripping scheme. The dependability, security, and cost of the proposed scheme is discussed within this paper an...

Transmission networks face continuous electrical and mechanical stresses due to increasing system challenges and power losses. Transmission networks require special focus and detailed studies each time a load or a generator emerges to the grid. The interline power flow controller (IPFC) is a relatively new scheme that is implemented in the transmis...

Arcing current faults (ACFs) occurring in a medium-low voltage $3\phi$ transformer represent a challenge for transformer protection. Such faults initiate currents with different features from those triggered by conventional faults, thus making it difficult for transformer protection to accurately detect and respond to arcing current faults. This...

Arcing current faults (ACFs) are undesired transient events that can occur in different power system equipment, including medium voltage-to-low voltage (MV-LV) power transformers. The main challenge in detecting, identifying, and responding to low-voltage (LV) side ACFs (in a MV-LV power transformer), is due to low magnitudes of MV side currents tr...

The global lockdowns adopted by many countries to combat the outbreak of the COVID-19 pandemic led to a significant transformation in the teaching methods adopted in higher education institutions toward dependence on online learning systems. Although this pandemic has placed a technical and financial burden on academic institutions to facilitate th...

This article investigates factors affecting the contributions of battery units to fault currents in grid-connected battery storage systems (BSSs). The work in this article is intended to examine the effects of the state-of-charge (SOC) on battery currents that are drawn due to faults. This article also examines the impacts of charger controller act...

In this article, the promising features of cognitive radio communication systems are used to propose a novel directional comparison blocking pilot relaying scheme. The proposed scheme will use relatively cheap, yet reliable, communication technology to transmit pilot signals between distance relays that are used for transmission line protection. Th...

This paper presents a method for evaluating smart grid functions that are implemented to operate residential loads. The proposed assessment method is developed based on the energy not-served (ENS) determined at a point-of-supply feeding residential loads. Smart grid functions can operate energy storage appliances (household water heaters, air condi...

This paper presents a method for evaluating smart grid functions that are implemented to operate residential loads. The proposed assessment method is developed based on the energy not-served (ENS) determined at a point-of-supply feeding residential loads. Smart grid functions can operate energy storage appliances (household water heaters, air condi...

Bulk wind farms are being increasingly connected to power systems all over the world. Normally, long transmission lines are used to deliver the power from remote areas where abundant wind power exists to load centers. Transmission lines are equipped with distance relays which serve as both main and backup protection. The integration of such farms p...

This paper investigates factors affecting the contributions of battery units to fault currents in grid-connected battery storage systems (BSSs). The work in this paper is intended to examine effects of the state-of-charge (SOC) on battery currents that are drawn due to faults. This paper also examines impacts of charger controller actions on the cu...

The unpredictable magnitude and phase angle of PV-integrated microgrids (PV-MGs) makes overcurrent protection highly unreliable. This paper investigates distance protection as an alternative to overcurrent protection for fault detection and allocation in PV-MGs through PSCAD simulations. The MG is integrated with distributed photovoltaic and synchr...

The fault current in a PV-integrated microgrid (PV-MG) has a relatively low value and an unpredictable phase angle, making current-measurement based fault detection techniques highly unreliable. This paper investigates the ability of conventional distance protection to detect and allocate balanced (LLL-G) faults on MG feeders emanating a PV inverte...

In this paper, the Harmony Search Algorithm (HSA) is proposed to estimate the optimal parameters of a hybrid active power filter (HAPF). Mathematical modeling of an industrial plant with linear and nonlinear loads combined with HAPF is developed. Four cases of study have been simulated using MATLAB/Simulink software to evaluate the effective perfor...

In this paper, a backup protection scheme is presented. The proposed scheme uses the concept of a cognitive radio-based wireless sensor network to implement a protection scheme without the need for conventional electric wires and/or optical fiber between current and voltage transducers, control panels, and circuit breakers. The proposed scheme uses...

Sliding Mode Control (SMC) has been widely utilized to control nonlinear systems with uncertain dynamics. This is due to its order reduction properties, low sensitivity to disturbances, great dynamic performance and ability to reduce the complexity of feedback control design by decoupling the system into independent lower dimensional subsystems. Th...

The fault characteristics for different types of wind generators are studied in this paper. Three types of wind generators are simulated within a microgrid that has the ability to connect and disconnect to a main grid. Types 1, 3, and 4 wind generators are simulated in both connected and islanded modes using MATLAB/SIMULINK software. The attributes...

In this paper, the fault characteristics of different types of wind generators have been investigated. Three types of wind generators, namely Types 1, 3, and 4, along with a microgrid are simulated in both islanded and grid-connected modes using MATLAB/Simulink software. The fault current contribution and voltage at the PCC during the fault have be...

In recent years, a lot of research efforts have been devoted to the application of sliding mode control (SMC) techniques to power electronic equipment and electrical drives. Hundreds of technical papers have been published in this research field. The tendency stems from the nature of sliding mode with discontinuous control actions and due to its po...

Village or community microgrids are being encouraged to improve resiliency against unexpected events. They also improve energy efficiency and reliability of power delivery to critical loads. However, many protection challenges exist in making the shift away from conventional distribution systems. In this paper, a multilayered protection strategy is...

In this paper, a comprehensive protection strategy is proposed for insuring dependable and secure operation of an islanded microgrid system. This is implemented using microprocessor based relays to prevent unnecessary loss of critical loads and distributed generators (DGs). Several improvements are proposed to clear the way for plug-and-play of dis...

New measures for increasing energy efficiency and reducing CO2 emissions are being introduced by several nations to tackle the growing concerns on climate change. This paper presents optimal distributed energy resource (DER) planning for establishing microgrids. Such microgrid systems are devised for industrial sites and campus communities in the U...

In this paper, a comprehensive protection strategy is proposed for insuring dependable and secure operation of an islanded microgrid system. This is implemented using microprocessor based relays to prevent unnecessary loss of critical loads and distributed generators (DGs). Several improvements are proposed to clear the way for plug-and-play of dis...

This paper presents the protection strategies for a medium voltage direct current (MVDC) microgrid at a remote area mine site. The microgrid is operated to provide high power quality and reliability to sensitive loads, and also improve the energy efficiency of the mining equipment. In the MVDC microgrid, various local distributed energy resources (...

It is well known that the control strategies of distributed energy resources (DER) have a major influence on protection schemes of both DER and distribution system. In view of that, coordination between the DER controls, DER relays, and distribution system relays is necessary to have a secure and reliable power delivery. Flexible Distribution of En...

Current transformers (CTs) are one of the key constituents of power system instrumentation and measurement, and their failure may lead to a breakdown of the entire protection scheme. The CT replacement or repair may not be feasible every time a CT malfunctions at a remote distribution substation as rural areas generally lack adequate skilled manpow...

A new framework for integrating distributed energy resources (DERs) and energy storage devices, known as Flexible Distribution of EneRgy and Storage resources (FDERS), has been proposed recently. It offers the benefits of increased DER lifetime, optimal energy storage deployment, enhanced controllability and improved system robustness. This paper p...

This paper investigates the design of a medium voltage direct current (MVDC) microgrid for a remote area mine site. The various aspects covered include its protection schemes as well as operation and control. This is intended to provide a voltage of high power quality and reliability at the sensitive load terminals, and also improve the energy effi...

The ever growing penetration of distributed generation (DG) in a distribution network has a profound impact on network protection and stability. Traditional protection schemes and algorithms need to be extensively investigated as more and more DGs get introduced into the network. The current version of IEEE Standard 1547 does not present a comprehe...

It is well known that the control schemes of Distributed Energy Resource (DER) have a major influence on protection schemes of both DER and distribution system. In view of that, coordination between the DER controls, DER relays, and distribution system relays is necessary to have a secure and reliable power delivery. Flexible Distribution of EneRgy...

Malfunctioning of distance relay third zone has been identified as one of the leading factors of power system blackouts in several nations. This inconsistency in operation happens when heavy loads start encroaching the zone 3 settings. In this paper, a novel multi-agent system based methodology for power system protection coordination is proposed....

The ever growing penetration of distributed generation (DG) in a distribution network has a profound impact on the network protection and stability. Traditional protection schemes and algorithms need to be extensively investigated as more and more DGs get introduced into the network. The current version of IEEE Std 1547 does not present a comprehen...

A multiband loop antenna that consists of a strip loop with two L-shaped arms connected together and designed to share the same feed and shorting points is introduced. In particular, this design can be considered to be an enhancement to the antenna presented in Chi and Wong (2007). The proposed antenna has sufficient bandwidth which makes it suitab...