stability

Open Access Article

1 - Investigating natural landslides and roadside by using shallow landsliding stability physically based model ( case study: Sari- Kiasar axis range)
Ali Talebi Alireza Motavalli

Communication networks and roads are important part of the investments of each country. Beside of this, maintenance of these large communication networks and process of developing construction are among the causes of the degradation of natural resources. In this resear More

Communication networks and roads are important part of the investments of each country. Beside of this, maintenance of these large communication networks and process of developing construction are among the causes of the degradation of natural resources. In this research , occurrence of landslides in Kiasar road, located in the south of Sari city, was evaluated by using basic physical model, SHALSTAB, and slope stability map of this area was determined by this model. First, the physical and mechanical properties of 15 soil sample near the main roadside were measured and compared with 115 cases of landslides around the road. Results of Square research, analysis of geological data, and laboratory tests showed that for all landslides occurrence, 43.49 percent of actual landslides have been located in unstable regions. Then, the roadsides have been distinguish from happened landslides, in natural conditions. Then a separated model has been run for each landslide. The results showed that whenever SHALSTAB model has been implemented by using roadside landslides, this model can simulated only 18.55% of slip points in unstable zones, and when SHALSTAB model implemented by using slips which occurred in natural conditions , by predicting 69.5 percent , is a successful usage. Manuscript profile

Open Access Article

2 - Estimation of stream bank erosion by BSTEM model
محمد مهدي حسين زاده Reza Esmaili

Stream bank erosion is known to be a major source of sediment shedding in streams and rivers. However it is difficult to define and estimate the contribution of sediment from river erosion. The purpose of this paper is to demonstrate the application of BSTEM model as a More

Stream bank erosion is known to be a major source of sediment shedding in streams and rivers. However it is difficult to define and estimate the contribution of sediment from river erosion. The purpose of this paper is to demonstrate the application of BSTEM model as a viable tool for identifying and quantifying the controlling bank-slope conditions for a range of stream-restoration objectives, evaluation of the importance of fluvial erosion, vegetation properties and near-bank pore-water pressure properties. The Bank Stability and Toe Erosion Model (BSTEM) were used in order to predict streambank retreat due to both fluvial erosion and geotechnical failure. In this research, BSTEM model also was used to simulate hydraulic erosion at the bank toe and bank stability during a series of flow events (bankfull discharge, mean annual flood, maximum flood discharge) for the purpose of evaluating current (existing) and potential changes in failure frequency (factor of safety or FS) and stream bank-derived loadings. The study site is located at the exit point of the Lavij river from the mountains in Kashpal park area (Chamestan-noor). Every year there is a significant amount of bank erosion caused by large floods in this river section. This study showed that for a multilayered stream bank in Lavij River, the most significant retreat occurred during a series of high flow events. In fact, the floods that occur with a return period of more than 10 years, play an important role in fluvial erosion and lateral retreat processes. Results of BSTEM analysis showed that lateral retreat measured at the stream bank in different scenarios ranged from 0 to 81cm and the bank stability conditions in the first scenario is unstable (FS =0.9), but in the second and thirds scenarios is almost stable (FS=1.15-1.26). Bank top vegetation provided additional cohesive strength to the top 1.0 m of the bank and resulted in a further reduction of failure frequency and failure volume. Results of this study showed that toe protection added to eroding stream banks can reduce overall volumes of eroded sediment. Manuscript profile

Open Access Article

3 - Analysis of stress regime in Shah Deniz oilfields and wellbore stability, in south Caspian Sea basin
Parvaneh Alizadeh Saeid Mohammad Hassanpour sedghi Ali Kadkhodaie Malek Mohammad Gity

Wellbore instability is one of the main problems during drilling of oil and gas wells. Analyzing and wellbore instability prediction is important. In-situ stress measurement and stress regime are important for stability studies. This study was carried out in one of the More

Wellbore instability is one of the main problems during drilling of oil and gas wells. Analyzing and wellbore instability prediction is important. In-situ stress measurement and stress regime are important for stability studies. This study was carried out in one of the oilfields in the south Caspian basin in Iran. The compressional stress regime in the studied field was determined based on regional stress indicators and larg scale tectonic observations. . This study presented the effect of borehole inclination and azimuth on borehole stability under reverse fault regimes. The magnitude of stresses was determined from measured sonic velocities, density log and predicted pore pressure utilizing the Eaton method. In this study, the modified Lade model have been utilized to perform stability calculation for different inclinations and azimuths. In this study, to perform stability calculation with the use of STABview software is presented. It is shown that drilling wells parallel to maximum in-situ horizontal stress (NE-SW) causes less stability problems. The results of this study could help in the mitigation and/ or prevention of wellbore stability issues in this oilfield. Manuscript profile

Open Access Article

4 - Hegemony in International Politics: Conceptuap Framework, Historical Experience and Its Future
jahangir karami

The concept of hegemony was first used in the third decade of the 20th centuty to analyze internal politics and it was only aftre 1960's that this term entered the domain of international politics. During 1970's the theorists of international political economy used the More

The concept of hegemony was first used in the third decade of the 20th centuty to analyze internal politics and it was only aftre 1960's that this term entered the domain of international politics. During 1970's the theorists of international political economy used the tern as a pivotal concept, but in fact it was only at the post cold war era that many debates began on this subject. In this article, hegemony is studied as an important concept in many different theories and ideas of international relations, which is equally very influential in the domain of international politics. Different views on hegemony are presented and studied in order to illustrate the reason behind the emergence, function, continuance and fall of a hegemonic power. The present situation of international politics as well as pro and con views of the American hegemony during last decades are also studied. Manuscript profile

Open Access Article

5 - Ibn Khaldun‘s “Loyalty” (Asabiyah) and Social Capital; an Analysis of Political Stability
aliakbar asadi kaviji Abolfazl Shakoori

Political stability and social order and, vice versa social decline and decay, are in the center of political and social thought. Centuries ago, an Islamic thinker, Ibn Khaldun discussed social order and political stability and gave a theory in regard of Loyalty (Asabiy More

Political stability and social order and, vice versa social decline and decay, are in the center of political and social thought. Centuries ago, an Islamic thinker, Ibn Khaldun discussed social order and political stability and gave a theory in regard of Loyalty (Asabiyah). Nowadays, the debates on social order and political stability have focused on the concept of “social capital”, and specific attitudes have developed among researchers. The aim of this paper is content analysis of Ibn Khaldun thought about Asabiyah, by comparing it with the concept of social capital; claiming that this can be done by a comparative study between new and traditional concepts. In this method we can throw a new light on the thinker’s thought in order to reload his thought for contemporary era and solving some of problems of current society. Manuscript profile

Open Access Article

6 - Stability Analysis of Networked Control Systems under Denial of Service Attacks using Switching System Theory
Mohammad SayadHaghighi Faezeh Farivar

With the development of computer networks, packet-based data transmission has found its way to Cyber-Physical Systems (CPS) and especially, networked control systems (NCS). NCSs are distributed industrial processes in which sensors and actuators exchange information bet More

With the development of computer networks, packet-based data transmission has found its way to Cyber-Physical Systems (CPS) and especially, networked control systems (NCS). NCSs are distributed industrial processes in which sensors and actuators exchange information between the physical plant and the controller via a network. Any loss of data or packet in the network links affects the performance of the physical system and its stability. This loss could be due to natural congestions in network or a result of intentional Denial of Service (DoS) attacks. In this paper, we analytically study the stability of NCSs with the possibility of data loss in the feed-forward link by modelling the system as a switching one. When data are lost (or replaced with a jammed or bogus invalid signal/packet) in the forward link, the physical system will not receive the control input sent from the controller. In this study, NCS is regarded as a stochastic switching system by using a two-position Markov jump model. In State 1, the control signal/packet passes through and gets to the system, while in State 2, the signal or packet is lost. We analyze the stability of system in State 2 by considering the situation as an open-loop control scenario with zero input. The proposed stochastic switching system is studied in both continuous and discrete-time spaces to see under what conditions it satisfies Lyapunov stability. The stability conditions are obtained according to random dwell times of the system in each state. Finally, the model is simulated on a DC motor as the plant. The results confirm the correctness of the obtained stability conditions. Manuscript profile

Open Access Article

7 - Explaining The Contexts of Achieving Sustainability in Old and Worn Textures with Integrated Urban Regeneration Approach; Case Study: The Old Texture of Kashan
Abozar Vafaei

Today, the old texture of Kashan as one of the urban areas, despite having concealed potentials and capacities for future urban development, holds an ample of problems including lack of urban services, inability of tissues residents, spread of social harms, low level of More

Today, the old texture of Kashan as one of the urban areas, despite having concealed potentials and capacities for future urban development, holds an ample of problems including lack of urban services, inability of tissues residents, spread of social harms, low level of health, insecurity, safety crisis and low resilience to calamities (physical instability). Therefore, to resolve these problems, traditional policies and approaches intervention in urban dysfunctional and worn tissues such as urban redevelopment and renovation cannot be accountable and there is a need to apply state-of-the-art patterns and approaches to place-based intervention in urban dysfunctional and worn tissues neighborhoods under the title of sustainable urban regeneration. This study intends to investigate the different dimensions of erosion and the challenges ahead in the old texture of Kashan to explain the context of sustainability realization in all dimensions of the texture with the approach of integrated urban regeneration based on analytical application. The research is categorized in practical sort in terms of purpose and analytical-explanatory in terms of using theoretical documents related to the research topic. The results show that integrated regeneration strategies in different dimensions of sustainability can be an appropriate model for resolving the problem of various types of exhaustion and the formation of a stable and intellectual spatial form in the old texture of Kashan. Manuscript profile

Open Access Article

8 - On the Stability of Primal-Dual Congestion Control Algorithm in the Presence of Exogenous Disturbances
A. moarefianpour V. johari majd

In this paper, we consider the effects of exogenous disturbances on the closed-loop system of the congestion control problem in a network with general structure. This investigation is important since many of data flows in internet network are considered as unmodeled flo More

In this paper, we consider the effects of exogenous disturbances on the closed-loop system of the congestion control problem in a network with general structure. This investigation is important since many of data flows in internet network are considered as unmodeled flows. In contrast to previous works, we suppose that both senders and links in the network have dynamics. Each sender updates its sending rate to minimize its own cost function. The network is modeled based on fluid flow approximation with nonlinear dynamics for the links. In this research, we first derive the conditions for the existence of the system equilibrium point taking into account the constraint sets of the problem. Then, we prove input-to-state stability (ISS) of the closed-loop system for the congestion control problem with input and output disturbances in the network links. We further show that the obtain results are valid even when the routing matrix of the network varies. Finally, we verify the theoretical results by simulation on two different multi-link networks. Manuscript profile

Open Access Article

9 - Power System Stability Improvement Using QFT-Based Excitation Robust Control
A. Akbari Forod H. Seifi A. khaki sedigh

Due to uncertainties in system modeling as well as system parameters, current excitation systems are unable to perform quite satisfactorily over a wide range of operating conditions. In this paper a QFT-based excitation robust control is proposed which the above mention More

Due to uncertainties in system modeling as well as system parameters, current excitation systems are unable to perform quite satisfactorily over a wide range of operating conditions. In this paper a QFT-based excitation robust control is proposed which the above mentioned uncertainties are, somehow, considered. The Horowitz second method is employed in the design of the nonlinear QFT controller. Manuscript profile

Open Access Article

10 - Application of Combinational Adaptive Load Shedding Schemes to Improve Power System Voltage Stability - Part I: General Concept & the Algorithms
A. Saffarian M. Sanaye-Pasand A. P. Ghaleh

In this paper three combinational adaptive load shedding schemes are proposed to enhance the power system stability especially voltage stability margins of the system following severe events. Nowadays, the security margin of power systems against various instabilities i More

In this paper three combinational adaptive load shedding schemes are proposed to enhance the power system stability especially voltage stability margins of the system following severe events. Nowadays, the security margin of power systems against various instabilities is decreased due to the developments, deregulation and competitions in the power industry. In this situation, traditional system protection schemes can not offer adequate protection especially against combinational events. In some combinational disturbances, after initial frequency drop the conventional protection schemes returns back the system frequency to its permissible values; however, the system eventually collapses due to severe voltage declines which result in voltage instability. In some other disturbances, severe voltage declines cause troubles in appropriate operation of the under frequency load shedding relays. In this paper three adaptive combinational load shedding schemes are proposed to counteract such disturbances. The proposed schemes use locally measured frequency and voltage signals and do not need any communication link. In the proposed algorithms, during under frequency condition, load shedding is started from the locations which have higher voltage decay and for longer period of time. The speed, location and amount of load shedding are changed adaptively depending on the disturbance location, voltage status of the system, and the rate of frequency decline. In the second part of this paper using model of a real network, various simulation studies are performed and performance of the proposed schemes is investigated. Manuscript profile

Open Access Article

11 - Application of Combinational Adaptive Load Shedding Schemes to Improve Power System Voltage Stability - Part II: Simulation Results
A. Saffarian M. Sanaye-Pasand A. P. Ghaleh

paper is part II of a two-part paper. In the first part, several adaptive combinational load shedding schemes were proposed to enhance the power system voltage stability. The main objective of the proposed schemes is to improve the voltage stability margin of the system More

paper is part II of a two-part paper. In the first part, several adaptive combinational load shedding schemes were proposed to enhance the power system voltage stability. The main objective of the proposed schemes is to improve the voltage stability margin of the system following large and combinational disturbances. For major disturbances the frequency and voltage stability of the system are jeopardized simultaneously and the conventional schemes might fail to operate correctly. In this part, the proposed methods are simulated in a real network to evaluate their performance. To achieve realistic results, dynamic model of generators, automatic voltage regulators, governors and loads are considered in the simulations. Considering the importance of load modeling in these studies, the frequency and voltage dependence of static loads have been modeled accurately. Dynamic motor loads have also been modeled using aggregate equivalent induction motors at load buses. Performance of the proposed schemes is compared with each other also with performance of the conventional scheme for various combinational disturbances. Considering the obtained simulation results it is concluded that by using the proposed algorithms the power system becomes more robust against large disturbances and the probability of the power system instability is decreased. Manuscript profile

Open Access Article

12 - Cost Allocation Framework for Small Signal Stability Ancillary Service in Deregulated Environment
E. Riahi Samani H. Seifi Mohammad Kazem Sheikh El Eslami

An ISO is responsible for responsible for keeping system security within its specified limits. Rapid demand increase on one hand and less investment on transmission system and the other hand, have resulted in more stress on existing transmission grids. Therefore, variou More

An ISO is responsible for responsible for keeping system security within its specified limits. Rapid demand increase on one hand and less investment on transmission system and the other hand, have resulted in more stress on existing transmission grids. Therefore, various types of stability should be monitored and controlled. The small signal stability (SSS) is a type which may be improved using power system stabilizers (PSS). In this paper, though using the non-dominated sorting genetic algorithm version II (NSGA-II), it is, initially, shown how the PSSs may affect the generation cost as well as the SSS. Moreover, the service provided by PSSs is introduced as an ancillary service. A cost allocation framework is prospect in which the PSS owners are properly paid for their services provided. Manuscript profile

Open Access Article

13 - A New Algorithm for Fast Mode-Switching and Control of TCSC in Less than Half Cycle A New Algorithm for Fast Mode-Switching and Control of TCSC in Less than Half Cycle
M. Nayeripour M. M. Mansuri

Thyristor Controlled Series Capacitor (TCSC) has been used for various purposes such as power system stability improving and increasing of loadability, loss reduction, line impedance compensation or power flow control. Fast switching of TCSC from capacitive mode to indu More

Thyristor Controlled Series Capacitor (TCSC) has been used for various purposes such as power system stability improving and increasing of loadability, loss reduction, line impedance compensation or power flow control. Fast switching of TCSC from capacitive mode to inductive mode and vice versa following the fault and clearing of it respectively, is an essential key for improving transient and even dynamic stability of power system which have not been considered significantly. In this paper a new algorithm for fast mode-switching and control of TCSC in less than half cycle is proposed for changing capacitive to inductive mode and vice versa in less than half cycle. Simulation results show that the proposed method is faster and more reliable in different conditions than the existing method and can be used more effective in transient and dynamic stability improvement. Manuscript profile

Open Access Article

14 - Risk-based Static and Dynamics Security Assessment and Its Enhancement with Particle Swarm Optimization Generation Realloca
M. Saeedi H. Seifi

Security assessment is traditionally checked using a deterministic criterion. Based on that, the system may be considered as secured or unsecured. If an unsecured condition is detected, preventive actions are foreseen to make it secure. Recently, risk based security as More

Security assessment is traditionally checked using a deterministic criterion. Based on that, the system may be considered as secured or unsecured. If an unsecured condition is detected, preventive actions are foreseen to make it secure. Recently, risk based security assessment is used in power systems. In this paper, risk-based static and dynamic security assessment is proposed and a new transient stability index is defined. In this paper, the risk index is used as an objective function in the generation reallocation algorithm. In this algorithm, the security is maintained using the generation reallocation. The algorithm is tested on IEEE 24-bus test system and its capabilities are assessed in comparison with a traditional OPF, in which the security is maintained based on a deterministic criterion. Particle Swarm Optimization (PSO) algorithm is used as the optimization tool. Manuscript profile

Open Access Article

15 - Optimal Location for Distributed Generation Based on Uuncertain Data
H. Goodarzi

The purpose of this paper is optimal location of distributed generation in electric distribution networks. Load uncertainty and desired voltage range has been modeled using fuzzy data theory. The objective function includes loss reduction, improvement of profile index a More

The purpose of this paper is optimal location of distributed generation in electric distribution networks. Load uncertainty and desired voltage range has been modeled using fuzzy data theory. The objective function includes loss reduction, improvement of profile index and voltage stability index with their relevant constraints, voltage constraints and transmittable power from the line. Load variation has been shown for three different time durations (peak, off peak and average).PSO technique has been used to optimize the objective function while Max-Min method has been applied to select the answer. Results produced from the proposed model have been provided in 5 different scenarios on a 33 bus system of IEEE. Manuscript profile

Open Access Article

16 - The Probabilistic Small Signal Stability Analysis and Coordinate Tuning of PSSs and TCSC in the Power System with Considering the Wind Farm Generation Uncertainty
H. Ahmadi H. Seifi

With the decreasing of the fossil fuels and increasing of the environmental pollution, using of renewable energy resources is growing rapidly. On the other hand, the restructured electricity industry causes to cooperation of the distributed generation resources in the c More

With the decreasing of the fossil fuels and increasing of the environmental pollution, using of renewable energy resources is growing rapidly. On the other hand, the restructured electricity industry causes to cooperation of the distributed generation resources in the competitive electricity market. In such situation, the presence of the wind farms in the power system in order to provide the system loads is quite favorable. However, wind farm generation depends on the wind speed and the uncertainty in the generation cause to some concerns about the connection and operation of the power system. So, in this paper, a probabilistic approach for small signal stability analysis with considering the wind farm generation uncertainty based on PCM method is proposed. The PCM method is based on the orthogonal polynomials which provide a linear model for desired output. The continuous changes of the wind farm generation level cause to variation on the operating point that the control equipment parameters should be adjusted based on the new operation conditions. Therefore, genetic algorithm and the approximate models which are obtained from the PCM method are used. In order to validate the proposed method, the IEEE 10-machine and IEEE 16-machine test system are used. Manuscript profile

Open Access Article

17 - Reactive Power Management in the Presence of Wind Turbine Considering Uncertainty of Load and Generation
E. Moharamy S. Esmaeili

Reactive power management is very important in power systems for the secure transmission of active power, especially when a part of system generation is provided by stochastic sources like wind energy. This paper presents a new algorithm for reactive power management in More

Reactive power management is very important in power systems for the secure transmission of active power, especially when a part of system generation is provided by stochastic sources like wind energy. This paper presents a new algorithm for reactive power management in the presence of wind generators and considering the stochastic nature of these sources and load simultaneously .In this regard, the proposed probabilistic algorithm, minimizes the overall cost function of the system considering the cost of each of the reactive power sources including wind generators. Besides economic issues, the voltage stability margin, having sufficient reactive power reserve in each area of voltage control and considering transmission congestion probability as technical aspects of the planning, have been investigated .Another advantage of this method compared to the previous one, is using of doubly-fed induction generator (DFIG) and its capability in providing reactive power considering the constraints of grid side and rotor side converters. The proposed optimization algorithm uses a multi objective function with different weighting coefficients. This algorithm is applied to minimize total reactive power, cost and losses and maximize voltage stability margin and reactive power reserve, simultaneously, meanwhile the probabilistic nature of wind and load forecasting inaccuracy is considered in this algorithm. The proposed method is implemented on the IEEE 30-bus test system and the simulation results demonstrate the effectiveness of proposed algorithm in real conditions for PMSMs against internal faults, especially inter-turn faults. Manuscript profile

Open Access Article

18 - Lateral Stabilization of a Four Wheel Independent Drive Electric Vehicle Using a Three Layer Controller and Sliding Mode Control
H. Alipour M. Sabahi M. B. B. Sharifia

In this paper, a new controller, for lateral stabilization of four wheel independent drive type electric vehicles without mechanical differential, is proposed. The proposed controller has three levels includes high, medium and low control level. Desired vehicle dynamics More

In this paper, a new controller, for lateral stabilization of four wheel independent drive type electric vehicles without mechanical differential, is proposed. The proposed controller has three levels includes high, medium and low control level. Desired vehicle dynamics such as reference longitudinal speed and reference yaw rate are determined by higher level of controller. In this paper, a new sliding mode controller is proposed and its stability is proved by Lyapunov stability theorem. This sliding mode control structure is faster, more accurate, more robust, and with smaller chattering than common sliding mode controllers. Based on the proposed sliding mode controller, the medium control level is designed to determine the desired traction force and yaw moment. In the lower level controller, suitable wheel forces and torques are calculated by an optimal cost function minimizing. Finally, the effectiveness of the introduced controller is investigated through conducted simulations Manuscript profile

Open Access Article

19 - Optimal Power Flow in the Smart Distribution Grid Based on the Optimal Load Curtailment and Voltage Stability Index Improvement
S. Derafshi Beigvand H. Abdi

Smart grid is the result of enabling consumers in the power system in order to play an effective role in the power system planning and operation processes. The communication, control, and measurement infrastructures create a two-way intelligent communication between use More

Smart grid is the result of enabling consumers in the power system in order to play an effective role in the power system planning and operation processes. The communication, control, and measurement infrastructures create a two-way intelligent communication between users and the network which facilitates the effective implementation of demand response programs (DRPs) such as the direct load control (DLC). In this paper, optimal power flow as an important research topic in the power systems is presented based on DLC and a new voltage stability index. Simple calculations, voltage dependence, indirect dependence to the load and network topology, and also not reducing the network into a two-bus equivalent model, have made the proposed voltage stability index more applicable to real-time calculations considering the load pattern changes. In the proposed method, the optimal load curtailment in some selected loads of the network, with the aim of improving the voltage stability index of the weakest bus is evaluated. Finally, in order to show the effectiveness of the suggested method, it is applied to a 69-bus radial distribution network as an intelligent system. Manuscript profile

Open Access Article

20 - A New Method for under Voltage Load Shedding Using Voltage Sensitivity and Load Reactive Power
J. Modarresi E. Gholipour A. Khodabakhshian

Load shedding is the last line of defense for controlling and stabilizing of the power system in the occurrence of a disturbance. Determining the amount and location of the load shedding are issues that the power system operators always have faced In this paper, a new m More

Load shedding is the last line of defense for controlling and stabilizing of the power system in the occurrence of a disturbance. Determining the amount and location of the load shedding are issues that the power system operators always have faced In this paper, a new method is proposed for determining the location of under voltage load shedding (UVLS). The proposed method, unlike the previous UVLS methods, uses two different factors to determine the effective location of UVLS. Considering the load reactive power in the process of determination of the UVLS location leads to disconnecting more reactive power during the initial steps of UVLS. Therefore, less active power sheds by the UVLS. To verify the accuracy of the proposed method, the proposed UVLS method accompanied with the method which uses the sensitivity of voltage with respect to the active power are implemented in IEEE 118-bus test system and New England 39 bus system. The obtained results show the superiority of the proposed method. Manuscript profile

Open Access Article

21 - Online Estimation of Transient Stability in a Two-Area Power System Based on Local and Wide-Area Measurements
M. Arabzadeh H. Seifi Mohammad Kazem Sheikh El Eslami

Transient stability analysis (TSA) is one of the important issues in the power system operation. The common methods of TSA are typically based on offline simulations so that some preventive and corrective actions may be designed to be adopted in real time conditions. To More

Transient stability analysis (TSA) is one of the important issues in the power system operation. The common methods of TSA are typically based on offline simulations so that some preventive and corrective actions may be designed to be adopted in real time conditions. To reduce the risk of these actions, in this paper a new method of transient stability estimation is proposed in which both local and wide-area measurements are used. According to the proposed method, the coherent generator groups of the two-area power system are initially identified and then the system is simplified based on the single machine equivalent (SIME) method. Thereafter, the equal area (EA) criterion is used to estimate the system transient stability. The innovation of this paper is the calculation of the acceleration area of SIME system based on the acceleration areas calculated locally in generator buses. The proposed method is applied on a10-mchine 39-bus test system and its results are presented by further explanation of its technical advantages. Manuscript profile

Open Access Article

22 - Algebraic Stability Analysis and Stabilization by Proportional Controllers: Critical Inflection Point in Phase Diagram
kh. Neshat M. S. Tavazoei

This paper deals with algebraic stability analysis and investigating the existence of proportional stabilizing controllers on the basis of frequency response data. Firstly, it is shown that using the available results in this subject may yield in inconsistent subsequenc More

This paper deals with algebraic stability analysis and investigating the existence of proportional stabilizing controllers on the basis of frequency response data. Firstly, it is shown that using the available results in this subject may yield in inconsistent subsequences in the cases that there is a critical inflection point in phase diagram of the open-loop/process transfer function. Then, to solve this inconsistency problem some modifications are proposed. Finally, conditions for ensuring the existence of critical inflection point in phase diagram of a dynamical system are analytically found. Manuscript profile

Open Access Article

23 - Stability Analysis of Doubly-Fed Induction Generator Wind Turbine Systems Using Modal Analysis
Ahmad Jafari G. Shahgholian M. Zamanifar

In this paper, the modal analysis of a grid connected doubly-fed induction generator (DFIG) using small signal stability analysis is presented and effect of variation in system parameters such as mutual inductance, stator resistance, line reactance, shaft stiffness and More

In this paper, the modal analysis of a grid connected doubly-fed induction generator (DFIG) using small signal stability analysis is presented and effect of variation in system parameters such as mutual inductance, stator resistance, line reactance, shaft stiffness and wind speed on the eigenvalues, stability and damping ratio of different modes of system are studied. This analysis shows that which parameters variation can deviate the system from normal working conditions as well as which parameters variation can improve the system behavior. For evaluating the stability and different controllers design, the simulation results show the effects of parameters variations. Manuscript profile

Open Access Article

24 - Distributed Control Scheme Based on Model Predictive Control for Supplying Power in an Isolated DC Microgrid
Arash Abedi Behrooz Rezaie Alireza Khosravi مجید شهابی

In this paper, a control scheme is presented for an isolated DC microgrid including wind turbine connected to permanent magnet synchronous generator, electrical energy storage unit, and variable electrical loads. Energy sources are connected to a common bus through DC b More

In this paper, a control scheme is presented for an isolated DC microgrid including wind turbine connected to permanent magnet synchronous generator, electrical energy storage unit, and variable electrical loads. Energy sources are connected to a common bus through DC buck and buck-boost converters. The local distributed controllers are located in the first control layer. These controllers are designed based on a Lyapunov stability analysis and thereby its stability is guaranteed. Moreover, the current and voltage, injected to the network, are adjusted by controlling the switching functions of the converters. The decentralized secondary controllers determine the contribution of the local units for supplying the local loads. In this control layer, a model predictive controller for the wind generation unit as well as a proportional-integral controller for preserving the bus voltage are proposed to determine the reference currents for the local controllers. In addition to the practical simplicity, complete isolation of the secondary controllers, minimum requirements to data transfer, and providing a control structure without any need to change in development plan are the important advantages of the proposed control scheme. The performance of the controllers is investigated and verified using the simulations in MATLAB software performed for different cases. Manuscript profile

Open Access Article

25 - Controller Design and Asymptotic Stability Analysis of a Buck Converter with a Cascade Control Structure Using Singular Perturbation Theory
Sajad Azarastemal Mohammad Hejri

This paper presents the theoretical proof for the closed-loop asymptotic stability of a DC-DC buck converter based on singular perturbation theory. Due to the two-time scales structure of this converter with fast and slow dynamics, a cascade control structure is used to More

This paper presents the theoretical proof for the closed-loop asymptotic stability of a DC-DC buck converter based on singular perturbation theory. Due to the two-time scales structure of this converter with fast and slow dynamics, a cascade control structure is used to control it. This controller has two control loops: an outer loop to control the output voltage based on the proportional-integral control and an inner loop to control the inductor current based on the sliding mode control. The controllers in the loops are designed based on perturbation theory to meet the constraints of the converter and ensure the asymptotic stability of the closed-loop system over a wide range of initial conditions. For validation, the proposed control design method is simulated for a typical buck converter in the MATLAB-SIMULINK environment. The simulation results show that by properly selecting the PI controller coefficients in the outer loop, the problem requirements are met, and the asymptotic stability of the closed-loop system is guaranteed in a wide range of the converter initial conditions. Furthermore, the system robustness against load uncertainty and input disturbances as well as the voltage reference tracking are evaluated, and the proposed structure is compared with a PI-PI structure. Manuscript profile

Open Access Article

26 - Improving the Transient Stability of Grid Connected Converter During Severe Voltage Drop by Virtual Impedance
Omid Abdoli E. Gholipour R. Hooshmand

With the rise in the penetration of inverter based distributed energy sources, grid codes say that converters should not be disconnected during the fault. These sources should also help the grid by reactive power injection. Power system grids are resistive inductive and More

With the rise in the penetration of inverter based distributed energy sources, grid codes say that converters should not be disconnected during the fault. These sources should also help the grid by reactive power injection. Power system grids are resistive inductive and the converter may be unstable during the fault. Converters use phase locked loop (PLL) to synchronize with the grid. PLL is not able to be stable during severe voltage drop, so converters cannot ride through the fault and should be disconnected. In this paper a novel method based on virtual impedance is proposed to maintain the synchronization during severe voltage drop. This method needs grid impedance estimation and virtually connects the converter to a point that has a stronger connection. By this novel method, during voltage drop, the converter stays connected to the grid and injects reactive power. Simulation results in MATLAB verify the ability of proposed method in improving the transient stability of converter. Manuscript profile

Open Access Article

27 - Sustainable development of the neighborhood in the direction of social happiness and public happiness (Analysis of principles, dimensions and indicators)
Shiva Shokri Raheleh Rostami Fatemeh Mozaffari

Sustainable development is a potential solution to some important social challenges such as happiness, which is an ultimate goal for human beings and happiness is often seen as an individual trait for which each person is solely responsible. However, it is also a social More

Sustainable development is a potential solution to some important social challenges such as happiness, which is an ultimate goal for human beings and happiness is often seen as an individual trait for which each person is solely responsible. However, it is also a social trait that is influenced by external factors. The present article reviews the parameters and goals of sustainable development to achieve happiness, the most important quantitative and qualitative criteria in five areas of happiness and ecological, economic, social and cultural sustainability through them, one can evaluate and promote happiness in neighborhoods and a brief insight about the neighborhood development project . The tool can also be used in future sustainable neighborhoods for fun projects. Finally, he suggests that sustainable development should promote happiness while rebuilding local economies and ecosystems, strengthening social ties and revives or preserves desirable cultural traditions, as well as provides an alternative framework for sustainable social development that focuses on improving the opportunities for happiness and well-being of society. Manuscript profile

Open Access Article

28 - A comprehensive study of shale intervals of Burgan Formation: implications for borehole stability
Mohammad سلیمانی سعیده رعیت دوست

Abstract This aims of this study is to characterize the Shale intervals of Burgan Formation from a borehole stability point of view. This paper describes the process and workflow for data-acquisition and interpretation in a shale formation characterization program an More

Abstract This aims of this study is to characterize the Shale intervals of Burgan Formation from a borehole stability point of view. This paper describes the process and workflow for data-acquisition and interpretation in a shale formation characterization program and demonstrates not only the benefits of acquiring specific data, but also highlights the uses of the data to aid the exploration decision process. The next purpose of this paper is to provide a research process that can be applied in similar geological settings. In the study process, we collected a complete set of information and samples from the field and presented a detailed case study, including laboratorial studies of formation samples and interpretation of the information. Available samples and information sources from Burgan Formation include drillhole cores. The minerals were defined by direct and indirect methods. Bulk XRD analyses performed on core samples showed presence of traces of clay minerals. For determination of the exact clay mineral type, clay minerals were extracted and treated by heat and ethylene glycol saturation. Treated samples were subjected to XRD analyses. Interpretation of the natural gamma spectrometry logs allowed the determination of the type and content of clay minerals. In a next step, in order to study the distribution of minerals types, SEM photomicrographs and Cation exchange capacity (CEC) of the samples were carried out. The results revealed that shale intervals of Burgan Formation are not expandable clays. The instability problem cannot be completely solved by drilling fluid design. The study shows, different approached methods reached the same results. Manuscript profile

Open Access Article

29 - Stabilizing and Synchronizing the Islanded Microgrid with the Presence of Sensor and Actuator Fault and Cyber-Attack with Secondary Controller Design
Abdollah Mirzabeigi Ali Kazemy Mehdi Ramezani Seyed Mohammad Azimi

In many microgrid control methods, the output information of sensors and actuators of neighbouring distributed generators (DGs) is used to stabilize and synchronize voltage and frequency. Many problems such as disturbances, uncertainty, unmodeled dynamics, cyber-attacks More

In many microgrid control methods, the output information of sensors and actuators of neighbouring distributed generators (DGs) is used to stabilize and synchronize voltage and frequency. Many problems such as disturbances, uncertainty, unmodeled dynamics, cyber-attacks, noise, time delay, and measurement errors cause invalid data problems and errors in the system. Better microgrid control depends on the quality of data measured or sent from the output of sensors and actuators. In this paper, according to the advantages of the Cooperative distributed hierarchical control, it is used for control and synchronization in the islanded microgrid with the presence of sensor and actuator error. To synchronize DGs with multi-agent systems and communication channels, it is modeled with graph theory. To stabilize and synchronize, sensor and actuator error in the DG model is mathematically formulated. In the proof of stability and synchronization, the appropriate Lyapunov candidate is presented and the conditions of stability and synchronization are proved. Finally, to show the effectiveness of the designed controller in solving communication channel problems and verifying the presented theory, a case study is simulated in the MATLAB/Simulink software environment with the presence of error and cyber-attack of sensors and actuators. Manuscript profile

Open Access Article

30 - Bounded Delays in Switching Signal for Switched Affine Systems
Arman Sehatnia F. Hashemzadeh Mahdi Baradarannia

In this article, the consequence of the presence of delay in the switch signal for switched affine systems is investigated. First, based on the principles of stability, the process of extracting the switch law as the only control input is examined, then by presenting th More

In this article, the consequence of the presence of delay in the switch signal for switched affine systems is investigated. First, based on the principles of stability, the process of extracting the switch law as the only control input is examined, then by presenting the practical stability issue for switched systems, more realistic view of these systems is proposed. The main focus of the article will be on the effect of delay in the transmission of switching signal information. The presence of limited delay in switching signal is usually caused by high volume of switching law calculations or any cyber attacks. In this paper, the practical Lyapunov stability results related to the states before and after the presence of delay in switching signal for a linear switched affine system are compared analytically and simulated. The results of the comparison of these modes show that when the value of delay in switching signal increases, the ultimate limit of the error for system states becomes larger, and this means a decrease in the convergence of the system states. In this regard, the results implemented for a DC-DC power converter and the necessary comparisons are presented in the last chapter. Manuscript profile

Open Access Article

31 - Polymer inclusion membranes for the extraction of rare earth elements
Zahra Daneshfar

The demand for rare earth elements has increased significantly due to potential industrial applications such as catalysts, magnets, battery alloys, ceramics. However, the separation and recovery of rare earth metals are very difficult due to their similar chemical prope More

The demand for rare earth elements has increased significantly due to potential industrial applications such as catalysts, magnets, battery alloys, ceramics. However, the separation and recovery of rare earth metals are very difficult due to their similar chemical properties and ionic radius, so progress in the separation process of these elements will bring many global benefits. Among the improved methods, the membrane technique has received much attention as a stable method with easy operation in the separation of such metals, and several membranes have been designed for separation. This article provides a summary of the types of membranes in the separation of rare earth elements in terms of extraction performance, transfer efficiency, and membrane stability. Polymer inclusion membranes are a new generation of non-liquid membrane that is made by a simple method of casting a solution containing liquid phases (carrier, plasticizer /modifier) and base polymers. Polymer inclusion membranes due to the possibility of simultaneous extraction and back-extraction, high selectivity, excellent stability, reusability, simple applicability, relatively low cost, and low energy consumption, it provides a great advantage in both the separation and purification of metal ions. Therefore, in this study, an overview of the PIMs reported in the studies to date is presented and the performance, permeability and stability of the membrane are discussed according to the base polymer, carrier, plasticizer and modifiers used. Manuscript profile

Open Access Article

32 - Depositional Environmental Analysis of Shally Units of Pabdeh-Gurpi Formation and Clay Minerals Effect on Wellbore Stability, Aghajari Oil Field
بهمن سلیمانی Zahra Dehghani

<!-- [if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:TrackMoves/> <w:TrackForm More

<span style="font-size: 10.0pt; mso-bidi-font-size: 11.0pt; font-family: 'Times New Roman',serif; mso-fareast-font-family: Calibri; mso-bidi-theme-font: major-bidi; mso-bidi-language: FA; mso-bidi-font-weight: bold;">This research is related to detect of clay minerals and geochemical changes of Pabdeh-Gurpi shale formations and their role in borehole instability in Aghajari oil field. For this purpose, these formations were investigated using NGS well log (one well ring), X-ray diffraction method (XRD) and XRF analytical method (11 samples from two wells). In the NGS log, the detected minerals are illite, montmorillonite, mixed layer, glauconite and feldspar. In the XRD method, clay minerals illite, montmorillonite, mixed layer, chlorite and kaolinite were identified in order of abundance.These minerals due to their sensitivity to react with water causes the instability of the borehole. The high ratio of Si/Al and changes of Ti and high level of Fe3+ and Mg are also a sign of the widespread presence of illite, chlorite and montmorillonite in the mentioned formations.   <span style="font-size: 10.0pt; mso-bidi-font-size: 11.0pt; font-family: 'Times New Roman',serif; mso-fareast-font-family: Calibri; mso-bidi-theme-font: major-bidi; mso-bidi-language: FA; mso-bidi-font-weight: bold;">The changes of major and trace elements compared to Al2O3 except for MnO, CaO, and P2O5 showed a positive linear relationship. The changes in the amount of Fe2O3 show the oxidizing conditions in the upper part of the base, but the reducing conditions towards the upper side. Based on the amount of iron, manganese and vanadium, the sediments were formed under conditions of reduction, non-sulphide reduction Eh and medium to low pH. Variations in Th/U ratio (1-4.5) indicate marine to transitional environments. The existence of horizons rich in organic matter (more than 2%) confirms the reduction conditions.   <span style="font-size: 10.0pt; mso-bidi-font-size: 11.0pt; font-family: 'Times New Roman',serif; mso-fareast-font-family: Calibri; mso-bidi-theme-font: major-bidi; mso-bidi-language: FA; mso-bidi-font-weight: bold;">Based on the low values of the Zr/Rb ratio, the sediments in the upper and lower parts are finer than the middle part of the grain. The relative accumulation of biogenic carbonate along with the shale is periodic and is reflected in the changes in the (Zr+Rb)/Sr ratio. Based on the Sr/Ba ratio, marine conditions prevail in the lower part and continental and metamorphic and sometimes marine conditions prevail in the upper part of the formation. Oxidation-reduction conditions were also investigated. The values of the V/(V + Ni) ratio of the semi-reduction region, the Ni/Co ratio of the reduction region and the V/Cr diagram show the almost reduction region and in some cases the oxidant conditions. Paleoclimatic conditions at the time of sedimentation based on low values of Rb/Sr ratio (less than 0.14) were completely hot and dry.   Manuscript profile

Open Access Article

33 - Analysis of the content of political development in the documents upstream documents (Constitutional Law and the 20-year vision document of 1404)
Moustafaa kavakebyan Azim Matin

This research delves into the intricate facets of political evolution within the framework of the Islamic Republic of Iran, particularly focusing on the confluence of constitutional governance and strategic foresight. Underlining the imperative of a meticulous scrutiny More

This research delves into the intricate facets of political evolution within the framework of the Islamic Republic of Iran, particularly focusing on the confluence of constitutional governance and strategic foresight. Underlining the imperative of a meticulous scrutiny of both the constitutional framework and the 20-year vision document of 1404, this inquiry probes into the reciprocal influence between the foundational precepts of the constitution, steeped in Islamic jurisprudence, and the transformative objectives delineated in the long-term perspective. Employing a methodical content analysis, the study scrutinizes the stance on political evolution as articulated in both the constitutional provisions and the 20-year horizon document, elucidating the nuanced dynamics that mold Iran's political trajectory. These revelations illuminate the state-driven, hierarchically structured nature of political advancement, underscoring the formidable task of harmonizing developmental initiatives with democratic principles and citizen engagement. This examination not only enriches scholarly discourse surrounding political progression but also furnishes policymakers with invaluable insights to navigate the distinctive socio-political terrain of the Islamic Republic of Iran. Lastly, this study underscores the constitutional emphasis on citizen participation and democratic values as pivotal components for fortifying political and social equilibrium. Manuscript profile

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