M.M.A. Salama

University of Waterloo | UWaterloo · Department of Electrical & Computer Engineering

Public transportation electrification is a topic of great interest due to its potentially significant impact on the reduction of greenhouse gas emissions. In order to electrify the public transportation system, the first stage is to determine the appropriate sizing of the necessary assets. Consequently, the goal of this work is the sizing of the fl...

The high penetration of distributed energy resources and heavy flexible loads, such as electric vehicles, has changed the operating conditions of the distribution network. In particular, the adoption of green energy innovations has caused an increase in electricity consumption. Such an increase can result in thermal overloading due to power flow ex...

Interconnected Microgrids (IMGs) are considered a futuristic paradigm of power grids that offer modularity, resilience, and independence with energy exchangeability. In this context, each MG is accountable to its own citizens (i.e., generators or loads) and can participate in a market with its neighbours, if this enhances the benefits of its citize...

Public transportation electrification is gaining significant traction due to its substantial positive environmental impact. However, the introduction of new electric fleets imposes a considerable additional load on the electrical system, creating a unique challenge that incorporates the interests of both transit agencies (TAs) and electric utilitie...

The electrification of the transportation system is double-edged for the smart grid. Although it is green and eco-friendly, uncontrolled charging of electric vehicles (EV) could cause not only distribution network congestion, but also long queues at the charging stations. Hence, it is necessary to ensure existing charging resources are efficiently...

Islanded microgrids have specific features that should be considered in their harmonic analysis. First, microgrids' distributed generators (DGs) are typically droop-based, and accordingly , the steady-state frequency is different from the nominal one. This affects the harmonics produced by DGs and nonlinear loads. Second, there is no slack bus, whi...

This paper develops a novel control approach for the droop-controlled Voltage Source Converters (VSC) of Multi-Terminal High Voltage Direct Current (MTDC) systems. The frequency consensus controller is shown to assist in damping the inter-area oscillations and providing enhanced mutual frequency support. Such features, however, might be achieved at...

This paper investigates the problem of cyber-attacks on Wide-Area Under-Frequency Load Shedding (WAUFLS), as these schemes are critical to maintaining power systems stability. First, we perform a detailed analysis on existing WAUFLS schemes and show that an adversary can launch a False Data Injection (FDI) cyberattack by manipulating the frequency...

As the main frequency controller in the electrical grid, the Automatic Generation Control (AGC) is one of the critical components that requires high level of security. A cyber attack on the AGC system does not only affect the operation of the AGC, but it also affects the whole system frequency. Previous research works have ignored the nonlinearitie...

A unified protection technique for different configurations of Multi-Terminal high voltage Direct Current (MTDC) systems is presented in this paper. The technique is based on using positive and negative poles’ currents of one end for each line. The spectral energy of two distinct frequency bands captured from fault currents, together with the fault...

Maintaining proper operation of adaptive protection schemes is one of the main challenges that must be considered for smart grid deployment. The use of reliable cyber detection and protection systems boosts the preparedness potential of the network as required by National Infrastructure Protection Plans (NIPPS). In an effort to enhance grid cyber-p...

Microgrids have the ability to function in islanded or grid-connected modes of operation. The increased penetration of inverter-based Distributed Energy Resources (DERs) in the system promotes the concept of partitioning the system into self-governing and self-adequate microgrids. Most of the partitioning techniques determine virtual boundaries and...

The increasing demand for energy storage systems (ESSs) alongside the continuous enhancements to storage technology have been of great positive impact on the electric grid. Their unceasing development has been driven by the need to accommodate increased penetration of renewable energy resources and defer capital investments, among other benefits. M...

This paper develops a novel control approach for the droop-controlled Voltage Source Converters (VSC) of Multi-Terminal High Voltage Direct Current (MTDC) systems. The frequency consensus controller is shown to assist in damping the inter-area oscillations and providing enhanced mutual frequency support. Such features, however, might be achieved at...

The substantial cost of voltage transformers in high and extra high voltage levels has persuaded power engineers to widely utilize Capacitive Voltage Transformers (CVTs) in transmission systems. CVTs, however, demonstrate an inferior transient response in certain situations, which distorts their secondary voltages. Consequently, the voltage wavefor...

Increased penetration of heavy loads is expected to lead to congestion in distribution networks. The distribution network operator can use Demand Side Management (DSM) to motivate consumers to shift their load from peak to off-peak times. In this paper, multi-objective optimization is utilized to schedule flexible load to alleviate potential conges...

In this paper, The IEEE thermal ageing model is utilized to build an enhanced Transformer Life Expectancy (TLE) model. The enhanced model is developed relying on the current transformer Health Index (HI) in addition to the loading conditions. A direct correlation between the IEEE and the (HI) ageing factors is identified and projected. The model is...

Market-based congestion management methods adopt Demand Side Management (DSM) techniques to alleviate congestion in the day-ahead market. Reliance of these methods on the communication layer makes it prone to cyber attacks affecting the security, reliability, and economic operation of the distribution network. In this paper, we focus on Load Alteri...

This paper develops a new control strategy for volt age source converter (VSC) based multi-terminal high voltage dc (MT-HVDC) grids for enhancing the mutual frequency support between MT-HVDC interconnected asynchronous ac systems. The existing control structure of VSCs is augmented with an additional feedback voltage-based loop that generates a vol...

Inter-connected Microgrids (IMGs) have emerged as a promising structure for future grids, offering resilience and independence in energy exchangeability with neighbours. To enable such interconnected structure, an interconnected market between individual Microgrids (MGs) participating via an agent (i.e., Energy Management System [EMS]) is required....

This article investigates the impact of battery energy storage systems (BESSs) on the distribution system energy management (DSEM). The article introduces a linearized multiobjective DSEM framework for reconfigurable smart distribution systems (DSs) in the presence of renewable distributed generators (DGs) and BESSs. The proposed framework aims to...

The DC microgrid (DC MG) concept enables the hosting of DC-type renewable energy resources. However, their intermittent nature means that a high penetration of renewables can jeopardize supply adequacy and voltage provision during islanding. The work presented in this paper was therefore directed at developing a probabilistic graphical approach bas...

This article proposes an auxiliary framework to address the challenges of transformer differential protection for single-phase transformers or three-phase transformer banks. This framework enables the differential scheme to: 1) work properly if transformers or current transformers (CTs) saturate; 2) detect internal and cross-country faults; 3) dete...

The severe impact of natural disasters on distribution system (DS) infrastructure highlights the importance of enhancing the resiliency of such systems. The loss of critical loads, one of the worst results of these events, increases the significance of resilient restoration approaches. In addition to distributed generators (DGs), which are common r...

Microgrid planning philosophies are changing from islanding in the case of abnormal conditions to independent sustainability for constant secure, reliable operation. Large independent operators foresee a shift from gigantic-grid bulk generation and transmission to distributed generation (DG) from smaller, interlinked grid clusters. Customers and th...

As the growing demand for battery energy storage systems (BESSs) generally follows the renewable energy sources (RESs) trend, the active management of BESS- and RES-based distributed energy resources (DERs) could effectively solve voltage-sag problems in active distribution systems (ADSs). DERs are typically interfaced with the grid through power-e...

This paper proposes a novel stochastic planning framework for bilayer microgrids (BμGs), which facilitates the integration of different types (AC and DC) of loads and distributed generations (DGs). In contrast to the conventional μG configurations that adopt single layer, the bilayer configuration has an AC layer in addition to a DC layer, where al...

Owing to its system independence and unmatched speed, Traveling-wave (TW)-based relaying has become a top contender for transmission and distribution systems. However, existing measurement devices, such as Current Transformers (CTs), are incapable of capturing the full frequency content of TWs, as their bandwidths are limited. Consequently, existin...

Technical developments in communication technology and measurement synchronization have facilitated the design of advanced protection schemes, such as Line Current Differential Relays (LCDRs). However, the superior performance of LCDRs is achieved at the expense of exposing them to cyber-threats, since cyber-induced intrusions against protective re...

This paper proposes a framework for solving voltage-sag and voltage-deviation problems in distribution networks using battery energy storage systems (BESSs). The proposed framework is divided into two parts. In the first part, a proposed stochastic planning algorithm determines the optimal sizes and locations of the BESSs that mitigate voltage sags...

This paper introduces a new control approach for Voltage Source Converter (VSC) stations in a multi -terminal dc (MTDC) grid to provide mutual frequency support among asynchronous ac networks. The developed coordinated control strategy modifies the active power references of each droop-controlled converter considering its adjacent ac system’s opera...

With the negative climate impact of fossil fuel power generation and the requirement of global policy to shift towards a green mix of energy production, the investment in renewable energy is an opportunity in developing countries. However, poor economy associated with limited income, funds availability, and regulations governing project funding and...

The accurate ratio-based current sharing, which is one of the desired features of the droop controlled dc microgrid, might be affected by the system impedance. Several strategies have been presented in the literature to achieve precise current sharing. This paper proposes a new controller reconfiguration algorithm that is capable to achieve enhance...

AC/DC hybrid microgrids (HMGs) represent a promising architecture that allows the hosting of a mix of ac/dc energy resources and ac/dc loads. Despite their potential, when islanded, HMGs impose operational challenges among of which are precise and stable power sharing, frequency restoration, and voltage regulation. Imprecise power sharing can resul...

This paper presents a comprehensive design procedure for isolated microgrids with a high penetration of nonlinear loads. The proposed microgrid planning approach simultaneously determines the sizes, locations and types of distributed generators (DGs) and shunt capacitor banks (CBs). The presence of nonlinear loads along with the capacitors of CBs o...

Line current differential relays (LCDRs) detect faults accurately and promptly, by comparing all currents flowing into the line. This type of relay has been identified in the literature as a reliable protection for lines in DC microgrids (MGs). LCDRs, however, lack the required resiliency against cyber intrusions, such as false data injection attac...

http://ietdl.org/t/LFO_I ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++Planning the integration of PV power systems into the grid necessitates an accurate modelling of renewable power generation. Global solar irradiance, weather tempe...

High penetration of distributed generation (DG) results in technical problems as voltage rise, voltage unbalance, substation reverse power, and transformer overloading. These problems adversely affect the connectivity of DGs either in the planning stage by decreasing the number of connected DGs, or in the operation stage by applying DGs' active pow...

This paper presents a method to find a reliable health index (HI) for oil-immersed transformers using reduced number of tests. The method depends on using the most important tests that are directly related to the transformer health. Field data for 90 working transformers were used to validate and test the proposed method. A linear relationship betw...

Meeting electricity demand in remote communities and non-electrified regions in the poor developing world is a challenge. Power generation is in shortage compared to electricity demand. Electric utilities either would enforce grid’s zonal load curtailment or not electrify regions. Controlling electricity demand can play a vital role in enabling ele...

Population dispersion necessitates grid expansion to meet electricity demand. For many developing countries and remote communities, meeting electricity demand is a challenge due to a power generation shortage and load variability highly driven by weather uncertainty. Electric utilities’ practical planning solutions are to disable electricity access...

This paper proposes a two-stage energy management scheme (EMS) for AC-DC hybrid smart distribution systems (DSs). The proposed EMS is formulated as a multi-objective optimization problem to minimize the DS operation costs and energy losses. The proposed EMS is achieved in two stages. In the first stage, a network reconfiguration algorithm determine...

A major concern associated with the connection of distributed generators (DGs) to distribution systems is the voltage rise problem. A solution introduced in many voltage control schemes is DG active power curtailment. However, this measure has a negative effect on both DG revenue and DG investment. This paper proposes the use of existing system res...

This paper presents a new generic approach for developing a Jacobian matrix for use with the optimization unit in real-time energy management systems (EMS) for unbalanced smart distribution systems. The proposed formulation can replace approximated calculations for real-time optimal power flow in an optimization unit while providing greater accurac...

Energy is an essential key to humanity progress and economy development. With the recent population growth, more energy resources are needed to be explored to handle fossil fuel power generation deficiency in correspondence to electricity demand growth. These resources’ deployment is governed by the policy regulating projects’ funding. Based on the...

For distribution network operators to make effective decisions about real-time applications, they should have complete knowledge of all system variables. However, measuring all variables is infeasible due to the large number of system buses and the consequently high cost of measurement devices. Network operators are thus in serious need of methods...

This paper introduces a stochastic multi-objective optimization model for the planning of AC-DC hybrid smart distribution systems (DSs). The proposed model determines the optimal AC-DC network configuration that achieves two main objectives: (1) minimizing system costs, and (2) maximizing system reliability. The second objective is achieved through...

This paper presents state of the art reconfiguration techniques used for service restoration in distribution systems under different practical considerations. The different formulations of the problem together with the different solution methods are presented to show the advantages and disadvantages of each formulation and each solution. Other aspe...

Abstract-- the high intermittency and uncertainty associated with wind energy have brought serious challenges to the power system operators, such as increasing the operating costs by increasing the requirements on primary reserves. Hence, the need to apply more robust and accurate forecasting model has become a persistent need to meet these challen...

This paper presents a comprehensive reliability framework for incorporating different PEV charging load models into the evaluation of generation adequacy. The proposed framework comprises special treatment and innovative models to achieve an accurate determination of the impact of PEV load models on reliability. First, a goodness-of-fit statistical...

This paper proposes a model for planning isolated microgrids. The goal of the proposed model is to minimize the investment, operational, and total costs of an isolated microgrid through the full identification of the system configuration. The model designates the optimal type of microgrid, i.e., ac, dc, or hybrid ac/dc, and the optimal sizing of bo...

The deployment of smart grids has facilitated the integration of a variety of investor assets into power distribution systems, giving rise to the consequent necessity for positive and active interaction between those investors and local distribution companies (LDCs). This paper proposes a novel incentive-based distribution system expansion planning...

This paper proposes a novel branch-based load flow approach for isolated hybrid microgrids. This evolving network configuration involves the application of a distinctive operational philosophy that poses significant challenges with respect to conventional load flow techniques. Hybrid microgrids are characterized by small-rating, droop-based distrib...

This paper proposes a new model for optimally allocating Plug?in Electric Vehicle (PEV) Charging Stations (CSs) in the network. The model considers Trip Success Ratio (TSR) in order to enhance CS accessibility for PEV drivers. Diversity of usage and different driving habits are considered in the presented model, as well as different trip types (In-...

This paper proposes a unified load flow (LF) model for AC-DC hybrid distribution systems (DSs). The proposed model can be applied in hybrid DSs with mixed configurations for AC/DC buses and AC/DC lines. A new classification of DS buses is also introduced for LF analysis. A set of generic LF equations has been derived based on comprehensive analysis...

Interest in microgrids is reaching the viral level, fed by the growing research attention and industry investment they are attracting. With its ingrained islanding capability, a microgrid can operate in isolation from the main grid while still keeping its load supplied for enhanced reliability and supply security. These microgrids represent the bui...

This paper proposes an economical staging planning method that optimally matches Plug-in Electric Vehicle (PEV) charging demand with the installation of Fast Charging Stations (FCSs) in the distribution system. The proposed plan consists of two stages. The first stage evaluates the capability of distribution systems to supply PEV charging demands w...

Meeting the growing electricity demand in many developing countries is a major challenge as there is a shortage in power generation. This paper proposes a novel strategy for mitigating the effect of weather intermittency on the scheduling power interruption of residential houses. The proposed method involves optimal scheduling strategy for the elec...

This article presents analysis of the systems in a Fuel Cell Electric Vehicle (FCEV) prototype with the aim of determining if it is possible to increase vehicle efficiency through strategic control of the auxiliary systems. To accomplish this, an overview of the vehicle design is given as well as an in depth analysis of the powertrain efficiency an...

Wind energy has become one of the most cost-effective renewable sources nowadays. However, the stochastic nature associated with wind-energy production represents a great challenge for power-system operations. Therefore, probabilistic techniques are necessary to evaluate the performance of power systems with substantial amounts of wind generation....

In this paper, a study of the effect of a group of transformer measurements on Health Index (HI) calculation is presented. Different methodologies for selecting the most efficient group of diagnostic measurements used in classifying transformer HI are investigated. A Binary Cat Swarm Optimization (BCSO) technique is undertaken based on Support Vect...