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Unanticipated faults can hinder the operation of the utility grid, consumers, and businesses. This study aims to ensure the continued power supply to the consumers during outages and peak hours from the stored energy in the batteries of electric vehicles (EVs). Considering the bi-directional charging feature, the energy capacity model of the EV-batteries in a centralized parking lot (PL) and distributed EVs is developed. Various factors that affect the energy capacity of EVs are considered and modeled. The optimal location of PL and charging/discharging time and rate are found for reliability improvement, losses reduction, and voltage regulation of the distribution system. The problem is formulated as a mixed-integer multi-objective optimization problem. The first objective function is formulated to maximize the energy output from the EVs-batteries during blackouts or to minimize the energy not supplied (ENS) to the consumers, whereas the second objective function minimizes the losses of the distribution system. Moreover, an IEEE 37 Node-Test Feeder and seven test cases are considered for this study. Simulation results show that PL of EVs could be employed as a power source during the islanded and grid-connected mode for improvement of reliability in the power systems.

This paper focuses on objective to get the real time data of the generator that will help the user to monitor the generator health and need of maintenance. Domestic consumers do not look over and study every detail in the instruction manual that they get with the generator and so, don't do preventive maintenance on their generator which results in breakdown. The designed system constantly monitors the generator, and helps to prevent damages. This system is specifically designed for household generators that run on gasoline, ranging up to 5KVA. The system consists of six different sensors being placed at different places on generator, through these sensors real time monitoring is done and data appear in the application with maintaining log of each activity. The data collected by the sensor is forwarded through Wi-Fi-module and is further sent to android application that alerts the user every time if the generator needs maintenance. The preventive maintenance based on grading index algorithm that shows alerts whenever the maintenance or ambiguity arises. By applying the designed system reduce maintenance issues and increase the life of generator, moreover with special feature it can count running along with that it measures the CO emissions.

The use of renewable energy systems (RES), as distributed generation (DG) units, in distribution systems is growing in recent years. DC distribution system is more feasible for the integration of renewable energy-based DGs as compared to the AC Distribution system. In DC distribution protection is the main issue because of low line impedance that causes high fault current. In this paper wavelet decomposition based protection scheme is proposed which identify the fault section in the distribution system and also identify which type of fault is occurred. Voltage and current signals, both are analyzed through wavelet. Sequence voltages are used for the input signal to wavelet decomposition for fault type identification. A communication channel is used between lines relays for the identification of faulty sections in distribution. A bipolar ring and radial type DC distribution systems are modeled on MATLAB/Simulink and different fault events are simulated.

Islanding detection has a very important role in power systems because it addresses many safety problems. A novel passive method for islanding identification in a distributed system is proposed in this paper. The proposed framework is discussed in two folds. In the first fold, the modal signal is calculated from a three-phase current, and its envelope is generated using a square law device (SLD). In the second fold, variance in autocorrelation of modal current envelop (VAMCE) is utilized as a detection basis for islanding. The autocorrelation function (ACF) of modal current (MC) envelop yields various transient features, which are then used to discriminate between the islanding and non-islanding situations. The smaller non detection zone (NDZ) and accuracy are the key advantages of this method. The VAMCE varies negligibly in normal conditions, however it varies significantly during islanding conditions, making this scheme a very effective tool for the detection of island. The scheme is evaluated using several simulations under different conditions, normal and islanded. It is found that the proposed scheme is quick and has better accuracy in comparison to other passive techniques.

Energy management system ISO 50001:2011 standard was developed in 2011 to cater requirement of energy efficiency and saving culture in order to control carbon emissions and production cost. This version was adopted by many organizations and industries. The second version of energy management system was revised in 2018 that focused on leadership role, procurement, risk and opportunities, competence and managing operations. However industries and organizations are hesitant to adopt this standard due to complexity doubts. In this paper a fast track implementation plan is discussed that can be adopted by any organization to ease the implementation and reduce the efforts. This half yearly plan covers all the major aspects of standard that is to be fulfilled by the organization in order to get ISO 50001:2018 certified.

Periodic cellular solids, due to their ability to provide high stiffness and strength to weight ratios, have become common in engineering applications requiring weight minimization. Such applications relate to aerospace, marine, renewable energy, and automotive industries. The continuously increasing industrial relevance of periodic cellular solids has motivated developing methodologies to improve their elastic and failure properties. Introducing hierarchical features in periodic cellular solids proved as one of the most effective methods to improve their in-plane elastic and strength properties. This approach was applied to aluminum honeycombs and resulted in more than doubling their in-plane stiffness. However, the effect of introducing hierarchical features on the out-of-plane properties of periodic cellular solids in general and honeycombs in particular has not been fully investigated yet. Accordingly, this work investigates the effect of introducing hierarchical features on the out-of-plane behavior of honeycombs. In particular, this work investigates, using finite element computations, the effect of introducing hierarchy on the buckling strength of hexagonal honeycombs. Results show that hierarchy when carefully introduced, can enhance the buckling strength of honeycombs by more than 170% without increasing their weight.

This paper presents a smart and efficient system for the surveillance of the ceramic and polymeric insulators installed in distribution system. Various manual methods are used to monitor the distribution system, but they are not efficient. They require more time, resources and also harmful for human life. The proposed system is able to monitor distribution line specially insulators using image processing and sensors reading. Complete system having quad-copter with camera resolution of 1080p, IR temperature sensor, humidity sensor and WiFi supported micro controller. Quad copter captures images of insulators and installed sensors take reading of the system. This system keep the record of all images taken along with GPS that provide ease to distribution company while locating faults on insulators. A GUI is created in MATLAB that is used for analyzing images through different image processing techniques. It monitors the condition of insulator by using the algorithm of canny filter and sober filter and create histogram of each image. Standard deviation and Mean value are also used to analyze the health of insulator. This system reduce the human effort and resources that consume more time and money.

Smart grids are likely to modernize the conventional power grids by commencing new sets of services and technologies which will enable the power system to be more sustainable, secure, cooperative and efficient. It is expected that the integration of more advanced communication and computing technologies will enhance the reliability and efficiency of the smart grids and eventually the overall power network. Unfortunately, one of the major issues of the smart grid is susceptibility to the cyber-attacks that eventually give rise to various problems related to control, communication, social and economic in the operations of the power network. The millions of devices in the power network are interconnected through a communication channel; thus, cyber-attack has a deep impact on the reliability of the system. In this paper, comprehensive analysis of the cyber issues of the smart grids will be discussed along with giving focus on network vulnerabilities, security requirements, techniques to detect the attack, countermeasures for attack and secure architectures and protocols of communication in smart grids. The primary purpose of this research is to develop the insight knowledge of the network vulnerabilities and possible solutions to them in smart grids.

This paper proposes an intelligent fault classification method for microgrids using a combination of discrete orthonormal Stockwell transform (DOST) and ensemble classifier. The proposed method first pre-processes the one cycle post-fault voltage and current signals using DOST. Then, the standard deviation of the DOST coefficients of the voltage and current signals is utilized to form the input feature vector to train and test the ensemble of classifiers. The ensemble classifier created by combining the hybrid base classifiers such as k-nearest neighbor (k-NN), support vector machine (SVM), and decision tree (DT) is used for classifying faults in microgrids. To evaluate the performance of the proposed method, we conduct a comprehensive evaluation study on a standard IEC microgrid test system using MATLAB/Simulink software. The test results confirm that the proposed method classifies faults in a microgrid with high classification accuracy.

Microgrids (MG) has become the most imperative issue in the modern research. A microgrid is a cluster of distributed energy resources (DER) along with energy storage devices in the premises of load, which provides the opportunity to employ renewable energy resources (RES), along with the traditional power system. In most of the developing countries like Pakistan, ageing and overloading of the transmission lines is one of the major problem in energy system. The old infrastructure of electric power grid is not proficient of compensating the increased demand of power. However, these effects can be encountered by deploying the distributed energy resources nearby to the load. Apart from technical constrains, there are certain non-technical issues regarding deployment of microgrids in Pakistan. This survey investigates the problems associated with the implementation of microgrid and its challenges, which hinder its deployment in Pakistan. In this paper microgrid policies of Pakistan, challenges and driving factors of microgrid have been investigated. This will help to motivate the people to implement DER's and MG. Ultimately it will accelerate the implementation process of MG and will improve the overall power system of Pakistan.

Continuous power supply is one of the major concern in modern world and for this purpose protection schemes must be efficient enough to overcome faults with minimum time. This paper presents the design of electromechanical and microcontroller (Arduino) based relay as an educational lab trainer to compare the behavior of both relays in over current protection of radial feeder. The proposed trainer introduces the use of both electromechanical and microcontroller based relays in a single panel in such a way that the system could be switched to either electromechanical or microcontroller based relay setup. It is designed for protection of two sections so that the concept of primary and secondary protection is observed. Microcontroller based relay setup is coded with IDMT characteristics and requires the values of PSM and TMS for the calculation of operational time of relay to clear the fault. This trainer also displays the magnitude of fault current as well as operational time of relay required to clear the fault. The fault is incorporated to the system by the insertion of low resistance path which leads to additional flow of current. Simulations are carried on Proteus and the hardware result shows that microcontroller based relays are fast in operation having less time of operation, more efficient and have very low cost as compared to conventional electromechanical relays. This trainer's idea could be implemented in engineering universities as a compulsory component for electrical power students.

This paper proposes an economical photovoltaic water pumping system with maximum power point tracking for extracting water in remote areas. MPPT algorithm is used to draw maximum available power from PV panels. The MPPT charge controller technology increases the efficiency of the battery charging state. Inside MPPT DC-DC converter is used to compare voltages of PV module to battery voltage. MATLAB simulations are used to check the DC-DC converter design and hardware implementation. Battery supplies 12V to operate DC pump and inverter converts 12V DC to 220V AC to run AC Load. The results authenticate that MPPT can fundamentally increase the proficiency and performance of photovoltaic panels. Analysis between A.C and D.C system is also presented which shows the cost-effectiveness of the system; Because of portable structure, it offers a great advantage for the user. Moreover, it is eco-friendly, has battery backup and is cost effective.

The assessment of technical losses is essential to the economics of the distribution network. Unbalance phases affect the performance of the system which results in power loss and continuous stress on the distribution transformers. This paper aims to provide evaluation of losses based on the surveys of a selected distribution network of the IESCO (Islamabad electric supply corporation) in unbalanced and balanced condition consists of different transformers with rating of 200 KVA and 100 KVA installed in residential and small commercial areas.

The increasing penetration of distributed generation (DG) units into power system networks has increased the overall reliability of global electricity consumption. DG integration also creates some challenges in the form of unintentional islanding, power quality, and bi-directional power flows. Islanding of DG units creates safety issues for the maintenance personnel and can damage protection equipment. The paper presents a passive islanding detection approach (IDA), which is based on voltage harmonics, extracted using a Kalman Filter (KF) model. A KF model is utilized to extract the harmonic features from the measured modal voltage (MV) signal at DG terminals. A derivative of the selected voltage harmonic distortion (SVHD) is considered as a decisive factor for islanding detection. The proposed IDA is validated using UL 1741 standard test cases, which confirm the reliability and efficiency of the proposed approach. The simulations are performed in the Matlab/Simulink environment. The results demonstrate that the proposed approach can detect islanding condition under worst operating scenarios and has a negligible non-detection zone (NDZ).

The frequency deviation of a system from its nominal value is a significant indicator of the system’s stability. This issue is further highlighted when the system is incorporated with intermittent renewable energy resources. In this work, frequency regulation of a microgrid is achieved by aggregated demand response. The proposed aggregator is implemented in a central controller that controls frequency deviation by manipulating responsive loads. In case of higher frequency deviation, an adaptive control action which is proportional to the magnitude of frequency deviation manipulates a large number of responsive loads to quickly restore the frequency to its nominal range. The amount of manipulated responsive load is reduced by another section of the central controller which deals with minor frequency deviations as well. The proposed control scheme is implemented on a test system and obtained results verify the desired functionality of aggregated demand response controller.

This paper presents the innovative solution of the unbalanced phases in the LV (low voltage) networks. A realistic data of eight transformers with different power rating has been taken. The data has been gathered from the area where unbalance phase problem is relatively frequent. An automatic phase load balancing methodology is proposed which can balance the load on three phases of transformers using a monitoring system. This system continuously checks the load on phases and gives feedback to the main control center. It gives command to each Slave unit through which switching device is connected. Furthermore power loss comparison and their economic effects before and after implementing the proposed technique have been discussed.

Cognitive radar offers an effective and optimal way for threat evaluation of suspicious target in cognitive radar. Controller based on fuzzy logic tools has been used in this study to solve such a complex problem. Proposed system due to enormous advantages of fuzzy logic, provide optimal solution. Fuzzy Logic Controller as an adaptive control for cognitive radar is effective scheme to solve complex problem like suspicious target detection in dynamic environment. In the proposed system, Fuzzy Logic Controller was used to evaluate threat rate of suspicious target for cognitive radar. We consider Altitude, Speed and Distance as an input parameters while threat rate of suspicious target as an output parameter. The results according to suggested rules belonging assigned MFs has been displayed in surface viewer. This shows that fuzzy logic as an efficient scheme for threat evaluation of suspicious target for cognitive radar. This system has also been verified by using mamdani's formula on specific values of inputs and output. Values from simulation are very close to values taking from mamdani's formula. In this study threat rating of suspicious target has been effectively estimated.