majid ajalli - Academia.edu (original) (raw)
Papers by majid ajalli
ABSTRACT In this paper DC microgrid small signal stability is studied. Droop based decentralized ... more ABSTRACT In this paper DC microgrid small signal stability is studied. Droop based decentralized control is assumed for micro grid control. Dynamic model of each component is derived individually and combined to form total state space equations of DC micro grid. Eigen values of system are also extracted. It is shown that under variation of PI controller the location of system poles changes.
Faults in MV systems are the cause of almost 70 percent of outages in power system. by using suit... more Faults in MV systems are the cause of almost 70 percent of outages in power system. by using suitable outage management methods, amount of power outages will be reduced in large extent. In Iran, traditionally outage management system was conducted by trial and error methods and relied on operators' experience. The ever-increasing expansion of distribution networks has made it impossible
Faults in MV systems are the cause of almost 70 percent of outages in power system. by using suit... more Faults in MV systems are the cause of almost 70 percent of outages in power system. by using suitable outage management methods, amount of power outages will be reduced in large extent. In Iran, traditionally outage management system was conducted by trial and error methods and relied on operators' experience. The ever-increasing expansion of distribution networks has made it impossible
Journal of Control, Automation and Electrical Systems, Feb 1, 2018
Nowadays, several test systems available in the specialized literature are used to verify studies... more Nowadays, several test systems available in the specialized literature are used to verify studies regarding power system planning or network reliability. However, there are no test systems currently available with enough information in order to endorse studies that simultaneously approach expansion planning, operation, and reliability issues. This paper introduces a real test system, including the load modeling, and generation and transmission systems. The main objective is to provide all the details and information required to evaluate methods and models developed for power system planning, operation, and reliability. The presented load modeling includes hourly, daily, weekly, monthly, and seasonal patterns. Furthermore, besides the substation data, reliability details, construction costs, and characteristics of right of ways (e.g., line length, impedance, and ratings) for the transmission system are exposed. The real transmission system presented contains 39 buses, 135 transformers, and 66 lines at two voltage levels: 230 and 400 kV. Finally, the generation system reliability data as well as operation and installation costs for each unit are also provided.
کچ ی هد لع ی مغر س نوزفازور دشر ی متس اه ی نورتکلا تخادرپ ی ک ی ، شقن کوکسم و سانکسا مه زونه مهم ... more کچ ی هد لع ی مغر س نوزفازور دشر ی متس اه ی نورتکلا تخادرپ ی ک ی ، شقن کوکسم و سانکسا مه زونه مهم ی تخادرپ رد اه ی ا درخ ی اف یم دننک زوت . ی ع اراک رد کوکسم و سانکسا بسانم یی ماظن دقن تخادرپ ی زه شهاک و ی هن اه ی لوت ی د راشتنا و رثؤم لوا ضرف .تسا ی ه ا ی ن اس هک تسا ی ر لماوع رثؤم کرت رد ی ب هب ی هن هب کوکسم و سانکسا تبسن و مجح :لماش کوکسم و سانکسا دقن ی گن ی ی ا لوت ی د لخاد صلاخان ی زوت و ی ع هقطنم ا ی راتخاس ،نآ ی ا س ی متس دادعت ،لوپ دحاو ازجا ی ازجا دادعت ،هکس ی رتکچوک ،سانکسا ی ن رتگرزب و ی ن ،سانکسا و هکس نورب از و هدوب بسانم وحن هب ی حارط ی ا فده .دنشاب هدش ی ن هب هلاقم ی هن زاس ی و سانکسا ءزج ره تبسن کرت رد هکس ی ب لوپ ی ارب .تسا ی تسد ی با ی ا هب ی ن صخت زا ،فده ی ص هب کوکسم و سانکسا ق ی تم هدرخ شورف ی فرصم تامدخ و اهلااک ی روگلا زا ماهلا اب و راوناخ ی مت رح ی هناص اضف رد ی مرن رازفا لتم ب اتن .تسا هدش هدافتسا ی قحت ج ی ن ق ی ب زا ی ج رتش هعما اب کوکسم و سانکسا هب مسا شزرا ی ) رتمک صخشم ار (درخ لوپ یم دزاس لحت اب . ی اتن ل ی ج هب و هلصاح اراک روظنم یی ب ی رتش گولج و ی ر ی...
IEEE Systems Journal, 2019
Power systems must be prepared to match the current growing demand for electrical energy. In this... more Power systems must be prepared to match the current growing demand for electrical energy. In this paper, the transmission network plays an important role, delivering the electric power generated in conventional power plants to load centers. For the last 45 years, the transmission network expansion planning (TNEP) problem has been widely studied; nowadays, TNEP, combined with new challenges, is being highly investigated, as researchers aim to reach a better solution. This paper presents a complete review and classification of the most significant works to date, providing a literary framework for TNEP specialists. Hence, a categorization of proposed models, case studies, innovations, and solution methods of the most relevant works regarding TNEP is provided. In order to establish a complete background, not only traditional approaches, but also those involving maintenance, uncertainties in generation and demand, reliability, electricity markets, energy storage, and risk management in TNEP are highlighted. This framework can help planners to improve previous formulations and methods and can propose more efficient models to better exploit existing infrastructure and reduce costs of investment.
Iranian Journal of Science and Technology, Transactions of Electrical Engineering, 2018
This paper studies transmission expansion planning (TEP) problem considering effects of wind farm... more This paper studies transmission expansion planning (TEP) problem considering effects of wind farms on transmission network congestion, power system reliability, line repair, and operational costs of wind and generating units in a deregulated environment. Transmission congestion is modeled using difference between local marginal prices (LMPs) of start and end buses of each line that is multiplied by its power flow. In this way, wind units can efficiently affect network congestion through decrease in lines loading and LMPs of buses. Transmission system reliability is modeled using load shedding (LS) index as well as outage rate and outage duration of a single line or simultaneous outage of a line and a wind unit. Also, generation reliability is formulated using loss of load, value of lost load, and LS criteria due to outage rates and outage durations of generating and wind units considering line limits. In addition, the effect of wind units on repair cost of transmission lines is modeled by the relationship among wind generation, line failure rates and lines loading. Operational cost includes cost of network losses, pollution penalty, fuel expenses, and generation cost of wind units. In order to more efficiently investigate the effect of wind power on TEP problem, the proposed model was tested on the IEEE Reliability Test System (IEEE RTS) for different scenarios, and the results were discussed.
Journal of Control, Automation and Electrical Systems, 2018
Nowadays, several test systems available in the specialized literature are used to verify studies... more Nowadays, several test systems available in the specialized literature are used to verify studies regarding power system planning or network reliability. However, there are no test systems currently available with enough information in order to endorse studies that simultaneously approach expansion planning, operation, and reliability issues. This paper introduces a real test system, including the load modeling, and generation and transmission systems. The main objective is to provide all the details and information required to evaluate methods and models developed for power system planning, operation, and reliability. The presented load modeling includes hourly, daily, weekly, monthly, and seasonal patterns. Furthermore, besides the substation data, reliability details, construction costs, and characteristics of right of ways (e.g., line length, impedance, and ratings) for the transmission system are exposed. The real transmission system presented contains 39 buses, 135 transformers, and 66 lines at two voltage levels: 230 and 400 kV. Finally, the generation system reliability data as well as operation and installation costs for each unit are also provided.
The Journal of Engineering, 2018
In this study, a transmission expansion planning problem is studied considering the effects of wi... more In this study, a transmission expansion planning problem is studied considering the effects of wind units on transmission congestion and power system reliability in a uniform electricity market. Market clearing price (MCP) is determined based on the maximisation of social welfare. Also, the congestion cost of a transmission system is defined as the difference between the cost of power supply before market clearing disregarding the transmission system (dispatching cost) and the operation cost of generating wind units of power suppliers considering transmission lines limit (re-dispatching cost). Dispatching cost is calculated using economic load dispatch and the re-dispatching cost is determined using optimal power flow. Moreover, the effect of wind units on transmission network reliability is studied through the relationship between wind units and lines loading and coherence between lines loading and lines failure rate. In addition, the effects of wind generation on composite transmission and generation reliability is formulated via the relationship between wind units and MCP and considering this price in loss of load and load shedding cost of customers. The proposed model is applied to the IEEE reliability test system and the results are discussed.
ABSTRACT In this paper DC microgrid small signal stability is studied. Droop based decentralized ... more ABSTRACT In this paper DC microgrid small signal stability is studied. Droop based decentralized control is assumed for micro grid control. Dynamic model of each component is derived individually and combined to form total state space equations of DC micro grid. Eigen values of system are also extracted. It is shown that under variation of PI controller the location of system poles changes.
Faults in MV systems are the cause of almost 70 percent of outages in power system. by using suit... more Faults in MV systems are the cause of almost 70 percent of outages in power system. by using suitable outage management methods, amount of power outages will be reduced in large extent. In Iran, traditionally outage management system was conducted by trial and error methods and relied on operators' experience. The ever-increasing expansion of distribution networks has made it impossible
Faults in MV systems are the cause of almost 70 percent of outages in power system. by using suit... more Faults in MV systems are the cause of almost 70 percent of outages in power system. by using suitable outage management methods, amount of power outages will be reduced in large extent. In Iran, traditionally outage management system was conducted by trial and error methods and relied on operators' experience. The ever-increasing expansion of distribution networks has made it impossible
Journal of Control, Automation and Electrical Systems, Feb 1, 2018
Nowadays, several test systems available in the specialized literature are used to verify studies... more Nowadays, several test systems available in the specialized literature are used to verify studies regarding power system planning or network reliability. However, there are no test systems currently available with enough information in order to endorse studies that simultaneously approach expansion planning, operation, and reliability issues. This paper introduces a real test system, including the load modeling, and generation and transmission systems. The main objective is to provide all the details and information required to evaluate methods and models developed for power system planning, operation, and reliability. The presented load modeling includes hourly, daily, weekly, monthly, and seasonal patterns. Furthermore, besides the substation data, reliability details, construction costs, and characteristics of right of ways (e.g., line length, impedance, and ratings) for the transmission system are exposed. The real transmission system presented contains 39 buses, 135 transformers, and 66 lines at two voltage levels: 230 and 400 kV. Finally, the generation system reliability data as well as operation and installation costs for each unit are also provided.
کچ ی هد لع ی مغر س نوزفازور دشر ی متس اه ی نورتکلا تخادرپ ی ک ی ، شقن کوکسم و سانکسا مه زونه مهم ... more کچ ی هد لع ی مغر س نوزفازور دشر ی متس اه ی نورتکلا تخادرپ ی ک ی ، شقن کوکسم و سانکسا مه زونه مهم ی تخادرپ رد اه ی ا درخ ی اف یم دننک زوت . ی ع اراک رد کوکسم و سانکسا بسانم یی ماظن دقن تخادرپ ی زه شهاک و ی هن اه ی لوت ی د راشتنا و رثؤم لوا ضرف .تسا ی ه ا ی ن اس هک تسا ی ر لماوع رثؤم کرت رد ی ب هب ی هن هب کوکسم و سانکسا تبسن و مجح :لماش کوکسم و سانکسا دقن ی گن ی ی ا لوت ی د لخاد صلاخان ی زوت و ی ع هقطنم ا ی راتخاس ،نآ ی ا س ی متس دادعت ،لوپ دحاو ازجا ی ازجا دادعت ،هکس ی رتکچوک ،سانکسا ی ن رتگرزب و ی ن ،سانکسا و هکس نورب از و هدوب بسانم وحن هب ی حارط ی ا فده .دنشاب هدش ی ن هب هلاقم ی هن زاس ی و سانکسا ءزج ره تبسن کرت رد هکس ی ب لوپ ی ارب .تسا ی تسد ی با ی ا هب ی ن صخت زا ،فده ی ص هب کوکسم و سانکسا ق ی تم هدرخ شورف ی فرصم تامدخ و اهلااک ی روگلا زا ماهلا اب و راوناخ ی مت رح ی هناص اضف رد ی مرن رازفا لتم ب اتن .تسا هدش هدافتسا ی قحت ج ی ن ق ی ب زا ی ج رتش هعما اب کوکسم و سانکسا هب مسا شزرا ی ) رتمک صخشم ار (درخ لوپ یم دزاس لحت اب . ی اتن ل ی ج هب و هلصاح اراک روظنم یی ب ی رتش گولج و ی ر ی...
IEEE Systems Journal, 2019
Power systems must be prepared to match the current growing demand for electrical energy. In this... more Power systems must be prepared to match the current growing demand for electrical energy. In this paper, the transmission network plays an important role, delivering the electric power generated in conventional power plants to load centers. For the last 45 years, the transmission network expansion planning (TNEP) problem has been widely studied; nowadays, TNEP, combined with new challenges, is being highly investigated, as researchers aim to reach a better solution. This paper presents a complete review and classification of the most significant works to date, providing a literary framework for TNEP specialists. Hence, a categorization of proposed models, case studies, innovations, and solution methods of the most relevant works regarding TNEP is provided. In order to establish a complete background, not only traditional approaches, but also those involving maintenance, uncertainties in generation and demand, reliability, electricity markets, energy storage, and risk management in TNEP are highlighted. This framework can help planners to improve previous formulations and methods and can propose more efficient models to better exploit existing infrastructure and reduce costs of investment.
Iranian Journal of Science and Technology, Transactions of Electrical Engineering, 2018
This paper studies transmission expansion planning (TEP) problem considering effects of wind farm... more This paper studies transmission expansion planning (TEP) problem considering effects of wind farms on transmission network congestion, power system reliability, line repair, and operational costs of wind and generating units in a deregulated environment. Transmission congestion is modeled using difference between local marginal prices (LMPs) of start and end buses of each line that is multiplied by its power flow. In this way, wind units can efficiently affect network congestion through decrease in lines loading and LMPs of buses. Transmission system reliability is modeled using load shedding (LS) index as well as outage rate and outage duration of a single line or simultaneous outage of a line and a wind unit. Also, generation reliability is formulated using loss of load, value of lost load, and LS criteria due to outage rates and outage durations of generating and wind units considering line limits. In addition, the effect of wind units on repair cost of transmission lines is modeled by the relationship among wind generation, line failure rates and lines loading. Operational cost includes cost of network losses, pollution penalty, fuel expenses, and generation cost of wind units. In order to more efficiently investigate the effect of wind power on TEP problem, the proposed model was tested on the IEEE Reliability Test System (IEEE RTS) for different scenarios, and the results were discussed.
Journal of Control, Automation and Electrical Systems, 2018
Nowadays, several test systems available in the specialized literature are used to verify studies... more Nowadays, several test systems available in the specialized literature are used to verify studies regarding power system planning or network reliability. However, there are no test systems currently available with enough information in order to endorse studies that simultaneously approach expansion planning, operation, and reliability issues. This paper introduces a real test system, including the load modeling, and generation and transmission systems. The main objective is to provide all the details and information required to evaluate methods and models developed for power system planning, operation, and reliability. The presented load modeling includes hourly, daily, weekly, monthly, and seasonal patterns. Furthermore, besides the substation data, reliability details, construction costs, and characteristics of right of ways (e.g., line length, impedance, and ratings) for the transmission system are exposed. The real transmission system presented contains 39 buses, 135 transformers, and 66 lines at two voltage levels: 230 and 400 kV. Finally, the generation system reliability data as well as operation and installation costs for each unit are also provided.
The Journal of Engineering, 2018
In this study, a transmission expansion planning problem is studied considering the effects of wi... more In this study, a transmission expansion planning problem is studied considering the effects of wind units on transmission congestion and power system reliability in a uniform electricity market. Market clearing price (MCP) is determined based on the maximisation of social welfare. Also, the congestion cost of a transmission system is defined as the difference between the cost of power supply before market clearing disregarding the transmission system (dispatching cost) and the operation cost of generating wind units of power suppliers considering transmission lines limit (re-dispatching cost). Dispatching cost is calculated using economic load dispatch and the re-dispatching cost is determined using optimal power flow. Moreover, the effect of wind units on transmission network reliability is studied through the relationship between wind units and lines loading and coherence between lines loading and lines failure rate. In addition, the effects of wind generation on composite transmission and generation reliability is formulated via the relationship between wind units and MCP and considering this price in loss of load and load shedding cost of customers. The proposed model is applied to the IEEE reliability test system and the results are discussed.