مهندس رضا غفارپور

Humans have always sought a solution to overcome the phenomenon of darkness and produce light in dark or low light environments. They have overcome this problem by inventing a variety of lights and lamps. In current lighting systems, the lighting source is located in the ceiling, which has advantages such as a relatively uniform distribution of light intensity in the entire environment centered on the location of the source and, of course, disadvantages such as the need for wiring in the ceiling. In places such as tunnels, buildings with high ceilings, very high arches, and such things, in addition to the high cost of wiring in the roof, if there is a need to repair or replace the lighting source, in addition to the great difficulty and risks, an additional fee should be considered for this purpose. In addition, the absence of a wire carrying electricity in the ceiling is one of the requirements in some places. In order to increase the safety of people and equipment and significantly reduce the cost, as well as not using the wire carrying electricity in the roof of some tunnels or buildings in order to comply with the principles of passive defense, a new lighting system has been proposed that uses LED light sources as lighting sources. The use of a collimated optical element, along with the use of a  reflector-diffuser system, in addition to removing the electricity transmission wire from the ceiling and the possibility of easy repair or replacement of the light source, also provide the required lighting for that place. The results of the experimental setup conducted using two different geometries for the reflector-diffuser system indicate that the use of the proposed method not only does not reduce the measurement lux of the light scattered in the environment but also increases the brightness to a small value.

Natural disasters and cyber-attacks pose many risks to the acceptable performance of power grids. In addition, the bitter experiences, gained from the recent Natural disasters in the country, lead to a greater focus on the concept of resilience. In this paper, a flexible method for improving the distribution network distribution resilience is proposed considering remote control switches and mobile power sources according to Tavanir Company policies. In the proposed method, changing the network configuration in real-time, controlling switches, and utilizing mobile power sources bring high flexibility and resilience to the network. The objective functions and constraints of the problem are completely linearized to reduce the complexity and solving time of the resilience problem. The mixed-integer linear programming method is used in the proposed method to optimize the objective functions. A modified IEEE 33-bus distribution system is utilized to evaluate the efficiency of the proposed method. According to the results, when the mobile power sources are located in the network based on the proposed method along with sending the repair team and operating switches after a disaster, the value of the objective functions and un-supplied loads are reduced by about 85 %. Therefore, the proposed method has a proper performance in increasing the resilience of distribution systems.

In today's societies, the power systems despite their vast developments as critical infrastructures (CI), are exposed to numerous natural and unnatural threats. In the past, power grids were designed only to withstand typical events which would have predictable probabilities. However, nowadays events with low probabilities and high effects are considered a major challenge. Power grids are expected to have the necessary flexibility in the face of such events and should not be disrupted quickly. This demonstrates the concept of resilience. In this article the resilience enhancement strategies, and in particular, the undergrounding as the best solution, are examined considering focused physical attacks. Taking budget constraints into account, the proposed algorithm determines the priorities of lines and buses to be undergrounded. This algorithm considers two approaches of the contingency analysis, namely the experts views and the index of load loss, in order to get the best choices for undergrounding. It should be noted that in this paper the static status of the grid is considered. Finally, the proposed method is implemented on the IEEE 39-bus test grid using Digsilent software, and the results are presented and discussed to evaluate the capabilities of the proposed method.

Nowadays, the impact of accidents with a low probability of occurrence and severe damage such as natural disasters and terrorist attacks on the power grid has been considered in many research works. According to the reported results, it is highlighted that such events can influence power systems in the form of long-term blackouts in large parts of the power system, the elimination of main equipment (ex. posts, transmission lines, and power plants), and the infliction of severe damage on the equipment. Therefore, the power system resilience concept is defined as the power system capability to reduce the effects that occur as a result of the occurrence of high-impact low-probability events. In other words, the goal of power system resilience is to create a potential capability for accelerating the recovery of the system from the impacts of such events and to adapt its functions and structure to reduce or eliminate the effects of these events. In this paper, a comprehensive review of power system resilience against high-impact low-probability events is provided. The related published works are classified in two parts including resilience against natural disasters and resilience against terrorist attacks. The published work related to each part is described in detail, and the papers of each sub-section are classified from different perspectives and the characteristics of all categories are presented.

Integrated demand response effectively promotes the use of renewable energy sources and improves energy efficiency in systems with multiple energy carriers. This paper proposes a resilient scheduling model for local energy systems based on electricity, cooling, hydrogen, and water in the presence of electric and hydrogen vehicles. In addition, the role of integrated demand response based on electricity and cooling to reduce the operating cost of the local water-energy system is investigated. The local energy system is equipped with electricity generation sources, a water desalination device, wind turbine, water, electricity, cooling, and hydrogen storage systems, an electricity to hydrogen conversion unit, and an electric chiller to simultaneously meet water and energy demands. To model the uncertainty of wind power generation, a robust optimization approach is used without the need for probability density function and scenario generation, which supports the optimal scheduling of the water-energy system against changes in wind power generation. It also enables the operator to apply a risk-averse approach. Numerical results show that using integrated demand response besides water-energy storage systems reduces the total operating cost of the local system by 5.6%.

Nowadays, the stable operation of urban infrastructure is of a lot of importance. The operation of infrastructure systems is often dependent to each other. One of the important concepts that is seriously affected by the dependence of such systems is resilience aganist extreme events. This paper proposes a comprehensive model for the resilience of critical infrastructures, especially the electrical grid and its associated infrastructure, faced with the damage caused by different attacks. In this model, three aspects of infrastructure are addressed: physical, human and cyber, each of which is defined based on the services they can provide. This modeling is developed based on the definition of a geometric graph. Since one of the most important infrastructures related to the electrical network, which is also a vital load for it, is the communication network, the proposed model is discussed in terms of the telecommunication system. This study focuses on the multi-time and multi-domain performance of the infrastructure, and considers the dynamics of the power system. Finally, in order to evaluate the proposed method, a numerical study is presented in which the case study is simulated using MATLAB software.

In recent years, the tendency to use renewable energy resources in remote areas has been raised due largely to increase in the energy demand and fossil fuel costs. In this paper, the aim is to find the optimal number of components of the off-grid hybrid PV/wind/battery/diesel system, in the presence of the load and renewable power generation uncertainty. Optimization is based on minimizing the value of the annualized cost of system, which meets the requirements of the desired loss of power supply probability (LPSP).Three various optimization algorithms including PSO, CPSO, and Modified PSO are proposed to solve the optimization problem. To exam the efficiency of the proposed model and optimization strategies, the proposed approach has been applied to a stand-alone hybrid energy system in Sistan and Bluchestan, Iran. Furthermore, the effect of different desired LPSP and optimization algorithms on the economic operation have been discussed. The results demonstrate that the MPSO has a faster solution and better performance than the PSO and CPSO. In this paper, while previous research has mainly focused on theoretical results only, for practical implementation, the maximum allowed constraint for diesel fuel consumption is added to the optimization algorithm and practical implementation has been done based on the simulation results and actual data.

With the warming of the weather conditions and significant load growth in the distribution sector, peak management in power systems has become an essential issue in hot seasons, and demand response programs are one of the most suitable common methods for managing peak. In this article, the authors propose a new approach to network peak management in critical conditions by the distribution company. This approach is the optimal scheduling of distributed energy sources and various demand response resources to reduce the network's peak consumption during critical peak hours and with the lowest cost. Demand response resources in this article include the three critical peak pricing, incentive-based load curtailment, and emergency load response, which the distribution company implements. The problem is optimized using a robust complex number linear programming and considering the power uncertainty of renewable resources. Providing a peak price 14% larger than the peak price of the normal tariff can bring a suitable load impact from the critical peak program customers in the network. The participation of customers in the load curtailment program in the beginning and end hours of peak management is equal to 30% and 20% of the customer's baseline. Considering the risk related to solar production, power contribution in this program increases by 117 and 74 kilowatts for the same hours. Adopting a risk-averse strategy increases the cost by 745 $ for the distribution company and the reason is the increase in curtailment of 120 kW through the emergency demand response program.

Nowadays, the human life in societies has become impossible without reliable operation of critical infrastructures. Therefore, many studies have focused on their operation and protection. One of the main fields in infrastructural studies is system modeling, especially with regard to interdependency. In this paper, recent studies on the modeling of interdependent infrastructures are reviewed. The purpose is to further protect the systems against disruptive events and to prevent cascading disturbances. One of the most effective and practical concepts in evaluating the impacts of perturbation and cascading interruptions is the concept of system resilience. Resilience, also known in the defense literature as passive defense, can provide a precise understanding of the probability of interdependent infrastructures' functionality. Therefore, in this review paper, interdependency modeling in infrastructure systems is investigated through the approach of system resilience against threats and disruptive events. To this end, various modeling approaches, are categorized into empirical, agent-based, system dynamics, economic, and network-based approaches and studied. Finally, the challenges that the researchers may face in the future studies are pointed out. The description of present challenges can pave the way for significant future developments in the field of interdependent infrastructure system modeling.

Islands are generally considered strategic points for enemy missile and drone strikes. Therefore, due to the vulnerability of these islands to such attacks and the need for sustainable energy supply, the concept of resilience is very important in the day-ahead scheduling of energy resources on the islands. On the other hand, with the increasing prevalence of emerging resources such as electric vehicles, electrical storage, and demand response programs in microgrids, the need for integrated scheduling to use the capacity of these resources to improve the resilience of these networks has increased. To this end, this paper examines a two-stage scheduling approach to reduce the daily operating costs and improve the resilience of an island microgrid integrated with wind turbines. In addition, the effects of coordinated scheduling of emerging energy sources, including grid-connected electric vehicles, an electrical storage system, and shiftable electrical demands are evaluated to improve the daily operating costs and system resilience. The resilience index is considered as the sum of the cost of load shedding and the cost of increased power production in the event of an enemy attack on the wind turbines. Therefore, the proposed model determines the best operation strategy under normal conditions in such a way that, in the event of an enemy attack on the wind turbines, the lowest cost of load shedding and the lowest cost of increasing production in the presence of emerging energy sources will be tolerated by the islanding microgrid.

Given the lack of access to the electricity distribution network in remote areas, rising fossil fuel prices and transportation costs, the importance of using renewable energy in these areas is increasing. Due to the high price of equipment such as wind turbine, solar panels and batteries, capacity sizing of the equipment is vital. In this research, the optimal design and practical implementation of renewable energy systems in a remote area in Sistan and Baluchestan province have been investigated and the net present value function has been modeled and solved by the GAMS software as MILP. In the following, practical implementation based on computer simulation has been considered and the operating scenario is set to 4 kW of solar panels, 28 seald acid batteries, 1200 W wind turbines and 4 kW inverter. Economic analysis shows that renewable energy systems will be utilized by a 35% reduction in costs relative to energy from diesel generators.

The purpose of passive defense plans is to reduce the vulnerability of human resources and critical equipment in the country. Therefore, compliance with non-operating defense principles is essential to prevent and reduce the risks of natural disasters such as lightning. Direct and indirect lightning strikes on buildings and transmitting current through incoming service lines can cause step-and-contact voltages that are harmful and dangerous to the humans and, the buildings and their valuable contents. In general, the step voltage is scattered to a radius of several meters around the location of the lightning stroke, causing injury to the people nearby. Therefore, from the passive defense perspective, the present study aims to minimize the damage of lightning strikes on sensitive centers placed at high altitudes and located in rocky areas. Since telecommunications and data stations are generally positioned in highlands or open areas, lightning protection is very important. Observing the compliance with international standards and recommendations in such environments, this paper uses the CDEGS Software to present the best and most optimal way to implement the ground system in order to minimize the step-and-contact voltages of telecommunication sites.

Passive defense principles are essential in the design and implementation of vital and critical plans as well as infrastructures to prevent and reduce the risks of natural disasters such as lightning. Lightning is a natural atmospheric phenomenon and there are no means to prevent it from happening. Direct and indirect exposure to lightning and the transmission of lightning discharge through the buildings and their inbound service lines can be harmful and hazardous to humans, buildings and their valuable contents, so it is imperative that measures be taken to protect against lightning. Since telecommunications and data stations are generally located in highlands or outdoors, lightning protection is essential and urgent. This paper provides an overview of the different methods of designing and implementing lightning protection systems and grounding of telecommunication sites at high altitudes and rocky terrains from the standpoint of international standards and recommendations. In this article, a review and analysis of earthing systems and lightning protection techniques and related international, military and communication standards for telecommunication towers on mountains and rocky land have been presented in order to design and propose a good quality protection system in accordance with relevant standards.

The electrical industry is one of the most sensitive energy-industries as the infrastructure and social life depend on it. This important energy source has always been subject to a variety of threats from hostile groups. This industry has a variety of assets that are each affected in a different way, and therefore a variety of immunization strategies and civil defense approaches are required. In this article these assets are explained separately, and civil defense requirements for each one, are discussed from the viewpoint of passive defense principles. These assets, which include network assets, such as major assets, communications facilities, human resources, machinery and tools, etc. are analyzed separately in this article. Then the relevant requirements and strategies for each asset are presented, according to passive defense principles and taking into account the issues of camouflage, surveillance, trickery, retrofitting, locating, scaling, scaling, moving, aligning, resuscitation and preparation and storage of spare-parts. In this way, executive solutions that can provide a comprehensive framework for passive defense can be presented.

Nowadays, critical infrastructures are more vulnerable to natural events, malicious physical and cyber-based attacks or intrusions. Since most societal functions rely heavily on critical infrastructures’ functionality, disturbances in any of them, can yield fatal consequences for interdependent infrastructures and subsequently, for the depending society. Therefore, critical infrastructure protection (CIP) has become an important research field in this century. In our country, to strengthen critical infrastructures and reduce the likelihood of willful attacks, possible vulnerabilities and negative consequences, it is imperative to consider the requirement of passive defense. Hence, critical infrastructure protection against any types of threats, as one of the goals of passive defense, would be achieved by developing and expanding appropriate strategies and guidelines. In this paper existing methodologies and national strategies for critical infrastructure protection is described. Resilience as a novel concept in common practices and strategies that have been applied in various countries to establish national protection plans, is investigated. In the concluding remarks, a set of strategic goals and also the most important challenges and requirements for developing critical infrastructure protection frameworks with a futuristic outlook are proposed. Thus, comparative research methodology is used to analyze the primary requirements of our national critical infrastructure protection strategy which could be counted as an effective step in achieving passive defense objectives.

The proper and sustainable performance of any electrical system is mainly related to the designers' insight into the nature of that system. Therefore, the need to provide an accurate model based on the actual behavior of the system has considerable importance. In the case of inverter-based microgrid, due to the lack of sufficient synchronizing torque, the design process must be carried out with the utmost precision. In this paper, the stability of the inverter-based microgrid will be studied. First by presenting the equations of the microgrid components its state-space model is obtained and in the presence of the static load model the stability of the system will be investigated. Then, by placing the inventory of dynamic exponential recovery and static polynomial load models, the results of the static model-based design are investigated. In this study, the measure of system stability will be eigenvalue plots and system performance. In order to achieve system stability and performance improvement, the state variables participation factors extracted and the effective parameters will be studied

Control systems based on internet are developing day by day. These systems are faced with many practical difficulties and challenges. Exchanged Information delay through the network is one of the most important issues of these systems and delay forecasting can make the user aware about the delays and missed data. As a result, the security system can prevent the cyber attacks. Predicting delays accurately, is a complex and difficult problem which has been studied by researchers, and several algorithms have been proposed to solve this problem. Artificial Immune System (AIS) and Particle Swarm Optimization (PSO) are two meta-heuristic methods based on stochastic search that has been developed to solve optimization problems. In this paper, the optimization model is presented. The AIS and PSO has been used as tools for optimization and the “Matlab” software has been utilized as a simulating tool to pridicting delays. In systems Comparing the results of AIS and PSO algorithm on the same data shows the efficiency and superiority of the AIS, both in terms of convergence speed and quality of response.

Recent advances in the field of information and communication technology (ICT) have led power system's operators to seek assistance from communication network for the continuity of normal operation of this critical infrastructure. However, connecting the communication network to the power system facilitated its operation, but nevertheless caused issues that were not previously apparent. One of these issues is the infection of damage from one infrastructure to another. Sometimes this damage goes so far as not to leave any connection between the infrastructures. In this paper, percolation theory has been used to find the threshold of disconnection of interconnected infrastructures. Two critical infrastructures are modeled as an interconnected network and then it is decomposed into three distinct graphs. By using the adjacency matrices of these three graphs, without actually simulating of any percolation process, the phase change diagram of interconnected network is drawn. Also, the most vital connections between the two infrastructures and the most vulnerable nodes of each infrastructure are identified from the consequences of the present model analysis. These results can be used in code regulation for connection of communication network to the power system.

The aim of optimal planning of renewable system is to maximize achieved benefits from this investment. Modelling the problem with more details will cause to achieve the results with more reality and practicality. One of the most important off-grid areas are border garrisons. Although, these spots are disconnected from each other electically, but, their energy usages are interconnected because of the presence of unique fuel transportation system. In this paper, the reduction of energy provision’s cost from a overhead organization’s aspect has been considered as objective function. To model the problem with elboration, the fuel transportation system has been considered as the one of cost source of problem. In addition, the constraints of economical evaluation have been written to guarantee the economic condition of carried out investment. The results of simulation using the test system including 4 garrisons, show that with an economical investment, the total cost of energy provision can be decreased up to 78%.

During recent years, increment of incentives for deliberate subversive activities against power systems along with the restrictions on the allocation of financial resources for protection of these infrastructures have absorbed significant attentions of researchers toward the necessity of optimal allocation of these finances; and such the way, to minimize damages and consequently energy not supplied in case of future events. Planners of subversive activities as fully strategic actors target those low probability events which are no considered in protection schemes to maximize quantity of damages to power system. In this study, a new game theory based scheme is proposed in form of a zero sum playoff in order to provide an optimal allocation strategy. In this paper, two budget allocation algorithms have been presented to protect transmission lines and substations against deliberate threats. In the first algorithm, allocation of a certain amount of annual funding to transmission lines and substations is formulated with the aim of attaining the best possible condition of power grid in term of system reliability; while, required budget and procedure of allocation of this budget to targeted system utilities against undefined strategy of malicious individuals are calculated in second algorithm, in order to reach a predefined level of system reliability. Proposed model is implemented employing MATLAB (i.e. to execute single-objective Cuckoo optimization algorithm as well as multi-objective non-dominated sorting genetic algorithm II) and GAMS (i.e. to determine reliability of grid by use of power system load flow) software. Totally, optimized game strategy of protectors to acquire the best condition of system reliability has been obtained. Results validate effectiveness and applicability of proposed method in cases of optimality of allocation technique and subsequently increase of reliability indices.

Readiness of power systems to cope with emergencies, especially those of sabotage origins, can improve the resiliency and minimize the restoration cost and time. In the current paper, in a tri-level robust decision making framework, system operator (SO) schedules the power generation for a base case in the upper level while a rational attacker tries to disrupt the most sensitive substation and consequently the connected generation units and transmission lines which leads to maximum load shedding in the middle level. Meanwhile, the SO once again tries to minimize the load shedding by redispatching the generation fleet in the lower level. In addition, in power systems with high wind penetration rates the SO should also consider the impacts of wind generation uncertainty for a more realistic robust scheduling. In contrast with two-stage robust methods with full recourse which immunize solutions against worst economic scenario (over-conservative solutions), the proposed column and constraint generation (CCG)-based model tries to find the base case solution while ensuring that in case of malicious attacks or wind realizations the solution can be adaptively adjusted with least load shedding. The performance of the proposed model is examined in 118-bus IEEE test system.

The efforts for better planning of power systems from various viewpoints, such as economic, technical, and environmental, for reliably meeting the demand are continued. The unit commitment (UC) is one of these planning problems. In this paper, the security-constrained unit commitment problem is addressed with focusing on the strategic importance of electrical energy in the presence of smart grids. To achieve this, firstly, a comprehensive UC model, amalgamating with emergency demand response programs (EDRP), is presented. To adapt the model with war condition, a modified form of EDRP, the so called strategic EDRP, is also proposed. The problem is formulated as a mixed integer linear programming problem solved via the GAMS. Then, to investigate the impacts of smart demand response programs on the reliability of load meeting, several scenarios are conducted regarding a stochastic contingency model for generating units under war condition. It is found in result evaluation that smart demand side contribution under war condition can increase reliability and so decreases the costs.

Power systems as main economic, security and natural life infrastructures have always been in the exposure of sabotage threats. Operational scheduling during disruptions, reducing probable damages, and reinforcing infrastructures considering passive defense goals are crucial and complicated tasks due to the large number of components in power systems and their interdependency and dispersion. Conventionally, passive defense is defined with a trihedral structure including prevention, protection, and response. However, due to emerging new security sabotage threats with low probabilities and high impacts beside natural disasters considering the resilience problem to lessen the impacts of disasters seems crucial. In this regard, the conventional trihedral augments to a structure with five pillars namely, prevention, protection, mitigation, response, and recovery. In the current paper these new concepts are discussed in power systems’ context. In the current literature, however, no practical quantitative measures are presented to precisely analyze the resiliency status of the system in different states (i.e. pre-event, during-event and post-event). Accordingly, the current paper firstly reviews and compares the common resiliency definitions in organizational, social, economic, and engineering systems along with electricity networks. Then, related but independent concepts such as risk, robustness, survivability, reliability, vulnerability and resiliency are compared and categorized. Finally, with assessing resiliency measures in social, national defense, and natural phenomena defining quantitative metrics for resiliency evaluation in electricity networks is facilitated. Eventually, explanation of recent aspects of resiliency in literature helps researchers to assess passive defense requirements in a resilient power system in a better way.

In the last decades, due to the emergence of new technologies, the usage of multi-energy systems has been widely increased. Therefore, it is very necessary to model and assess the maximum energy supply for consumers. Also, maintenance and development of resources and infrastructures against natural disasters and external threats become very essential in sustainable development programs. Recently, due to the severe dangers of climate change, as well as external threats, such as terrorist attacks, there has been a potential increase in power outages, which illustrates the value and importance of improving the resilience of energy systems. In this paper, a military center has been considered as a multi-energy microgrid. In this test system, the infrastructure of different energy carriers like gas and electricity has been used to provide the required amount of energy in the event of an attack, as well as to increase the security and resiliency of the multi-energy system.Also, the resiliency index is used for passive defense purposes to provide accurate estimation of energy security for a military center.

With increasing demand for fresh water and reduction in the investment cost of the renewable energy technologies, many of remote areas and small islands like the Abu-Musa Island are considered as potential markets for renewable energy based desalination systems. Therefore, in this paper, optimal investment of an off-grid hybrid renewable system is studied to supply customers electrical energy demand, as well as electrical and thermal energies required by the desalination units to provide drinking water consumed in the island. The simulation results for different desalination methods including multi-stage flash, multi-effect distillation, and reverse-osmosis are considered and analyzed. According to the results, although the average energy consumed in order to produce drinking water has the lowest value in reverse-osmosis method in comparison with the other two methods, but, the system net cost in the multi-effect distillation method is lower than the other two methods.