Series Of Facts Research Articles

Application of Hybridized Model of Shunt and Series Facts Controllers for Improvement of Generator Oscillation Damping Stability of Electrical Power System

Application of Hybridized Model of Shunt and Series Facts Controllers for Improvement of Generator Oscillation Damping Stability of Electrical Power System

Modeling and Simulation of Static Synchronous Series Compensator and It’s Applications in IEEE 14-Bus System

The growing demand for electricity has been a main reason for many blackouts. The way we transmit electricity now can't support the high need for power. This is making the voltage, which is like the electric pressure, unstable, which results in a big problem when managing the power grid. So, it's really important to understand how much load, or demand, the system can handle without getting messed up. Stability is a key concept, especially voltage stability. This means the power system's ability to keep the voltage at good levels at all points, both when things are normal and when there are problems or malfunctions. The unstable voltage happens because of higher demand for power, changes in the way the system works, and when the voltage drops in overloaded power grids. Checking voltage stability is a basic way to figure out if a system is safe. In order to make the system healthy there is a need of a series FACTS device to maintain certain power and voltage profile even though it’s subjected to practical disturbances.

Series FACTS Devices for Increasing Resiliency in Severe Weather Conditions

Severe weather conditions are low-probability, high-impact events that affect grid operations. The majority of power outages are caused by severe weather conditions. Grid resiliency to weather events can be enhanced by decreasing the reliance on its affected sections. One way to do this is to reduce the power flow through lines vulnerable to severe weather. If a line is disconnected, its initial power flow is distributed through the neighbor lines, which may cause congestion in the grid. FACTS devices can be used to control the power flow of lines that have a higher chance of power outages. Most previous works do not consider weather events in power flow control. In this work, a linearized optimal power flow (OPF)–based algorithm is developed to minimize the real power flow of vulnerable lines considering the thermal limits of lines to prevent infeasible solutions; the simulation is fast, making it suitable for large-scale systems. The proposed optimization problem is presented as a mixed-integer linear program (MILP), making it capable of using short-term load forecasting due to its high solution speed. The proposed optimization problem considers multiple lines with different outage probabilities and the uncertainties of the weather forecast. Moreover, it estimates the power reduction in vulnerable lines due to changes in the series FACTS devices. The performance of the proposed optimization problem is tested on IEEE 14-, 30-, and 118-bus systems for several scenarios. The results are validated with the AC power flow results from MATPOWER.

" Optimal Location and Sizing of Series FACTS device to Minimization of Power Loss and Voltage Magnitude "

" Optimal Location and Sizing of Series FACTS device to Minimization of Power Loss and Voltage Magnitude "

Power transmission system stability using sssc series facts device with heuristic and hybrid heuristic optimization techniques

This paper presents a hybrid algorithm using a Hybrid Firefly and Particle Swarm Optimization (HFPSO) algorithm to determine the optimal placement of SSSC devices. A multi-objective function is used to increase voltage stability, voltage profile and minimize overall power losses of the transmission system. At first, PSO algorithm is used to find the optimal SSSC location and further more to reduce the power losses and voltage profile enhancement to overcome the sub-optimal operation of existing algorithms. The HFPSO algorithm is used to determine the optimal placement of SSSC series FACTS device and verification of the proposed algorithm was achieved on standard IEEE 14-bus and IEEE 30-bus transmission systems in the MATLAB environment. Comprehensive simulation results of two different cases show that the proposed HFPSO demonstrates significant improvements over other existing algorithms to enhance voltage stability and reducing active and reactive power losses in electrical power transmission systems.

Voltage stability assessment of grid connected PV systems with FACTS devices

Three static techniques (i.e. Power flow, Continuation Power Flow (CPF) and the Q–V curve) are used to assess the voltage stability of the power grid with a Solar Photovoltaic Generator (SPVG) and FACTS devices under nominal and heavy loading conditions. A static model is proposed for the power system that includes conventional power generation units and SPVGs with FACTS devices. Two models of SPVG were used (i.e., PV-model and PQ-model) to elucidate the effect of the SPVGs on the stability of the voltage under various operating conditions. The best location for FACTS devices was obtained under nominal and heavy load conditions using static techniques. A comparison between series and shunt FACTS devices under nominal and heavy loading conditions was carried out using the three static techniques. The interaction between SPVGs and FACTS devices was detailed in this paper. The proposed approach was tested on the New England 39-bus standard test system, and the results confirmed the effectiveness of the proposed approach under various operating conditions.

Congestion management in deregulated power system by series facts device using heuristic optimization algorithms

Conventionally in many countries, electrical power industry is organized as vertically integrated system. Under this system, large utilities are authoritative for the generation, transmission and distribution of electrical power. Such utilities are governed by the rules and regulations of the government and are forced to operate within the prescribed guidelines with minimal profit. This confirmation causes an ineffective and sluggish perspective in power industry with a lack of technical innovation, competent management and customer satisfaction. To overcome these deficiencies, power sector around the globe is getting restructured. This paper addresses an inevitable technical disputes occurring in deregulated environment i.e., transmission congestion which has an adverse effect on system security, increase in electricity pricing and line losses. Flexible AC Transmission System (FACTS) is a boon to the power sector which helps in a better and reliable power flow through the transmission lines. The problem is articulated as a multi objective function satisfying all the operational and security limits. Three heuristic algorithms namely Particle Swarm Optimization (PSO), Symbiotic Organism Search (SOS) and hybrid Quantum based PSO-Bio-geography based krill herd optimization (Q-PSOBBKH) algorithms were applied in finding solution to this complex congestion problem. To study the effectiveness of the proposed objective, IEEE 14 bus system was considered as the test system. In order to validate the proposed methodology three congestion cases i.e. bilateral transaction, multilateral transaction and overloading were imposed on the test bus system. Simulation was carried out in MATLAB.

Enhancement of Transient Stability of a Series Compensated Long Transmission Line By Using Series Facts Controller

Enhancement of Transient Stability of a Series Compensated Long Transmission Line By Using Series Facts Controller

Series FACTS controllers in industrial low voltage electrical distribution networks for reducing fault current levels

In this paper, series FACTS devices like Thyristor control series capacitor(TCSC)and Static synchronous series compensator (SSSC) with designed control logic used to reduce the fault current located in LV distribution network at the LV busbar. The electrical distribution network in small and medium scale industries such as steel plants, process and power plants is through low voltage switchgear (LVS) fed from motor control centre (MCC) switchgear through step down transformer of 11kV or 33kV /415V. The designed switchgear in the LV side for these utilities usually is at 50kA. However, the process loads are continuously increasing and sustained with additional feeders with the existing switchgear. Consequently, the fault current at the busbar of the switchgear increases which may require the replacement of entire switchgear to the new design fault current. However, upgrading the existing switchgear is not an economical solution to the industries. Alternatively reducing the fault current at the busbar is feasible. Controller design implemented for reducing the short circuit current with series FACTS devices. A study carried on 800 MW Thermal power plant Ash handling LVS in ETAP and Matlab. It is observed that the results are encouraging to use series FACTS devices effectively in the LVS.

Twitter sentimental analysis from time series facts: the implementation of enhanced support vector machine

Sentiment analysis through textual data mining is an indispensable system used to extract the contextual social information from the texts submitted by the intended users. Now days, world wide web is playing a vital source of textual content being shared in different communities by the people sharing their own sentiments through the websites or web blogs. Sentiment analysis has become a vital field of study since based on the extracted expressions, individuals or the businesses can access or update their reviews and take significant decisions. Sentimental mining is typically used to classify these reviews depending on its assessment as whether these reviews come out to be neutral, positive or negative. In our study, we have boosted feature selection technique with strong feature normalization for classifying the sentiments into negative, positive or neutral. Afterwards, support vector machine (SVM) classifier powered with radial basis kernel with adjusted hyper plane parameters, was employed to categorize reviews. Grid search with cross validation as well as logarithmic scale were employed for optimal values of hyper parameters. The classification results of this proposed system provides optimal results when compared to other state of art classification methods.

Multi-objective resilient-constrained generation and transmission expansion planning against natural disasters

In this paper, the resilient-constrained generation and transmission expansion planning (RCGTEP) considering natural disasters such as earthquake and flood is presented. The proposed model contains a two objective problem that the first objective function minimizes the construction and operation costs of resiliency sources (RSs) and, in the second objective function, the minimization of the expected energy not supplied (EENS) due to the outage of the system against the mentioned natural disasters is formulated. Also, the proposed model is constrained to linearized AC optimal power flow (AC-OPF) equations, the planning and operating of RSs constraints such as generation units, hardening transmission lines, parallel and series FACTS devices, resiliency constraints and power system angular stability against earthquakes and floods in the presence of critical and non-critical loads. In order to achieve the best compromise response, the RCGTEP single-objective problem is formulated based on the ε constraint-based Pareto optimization. In addition, this model has the uncertainty of RSs availability against natural disasters, so stochastic programming is used for RCGTEP. Then, the Benders decomposition (BD) method is used to solve the proposed problem and achieve the optimal solution in the shortest possible time. Finally, by implementing the proposed model on an IEEE standard transmission network, the numerical results confirm the capability of this method in improving the economic, operation, angular stability and resiliency indices of the power system simultaneously.

Guaranteed Convergence Embedded System for SSSC and IPFC

This letter presents a holomorphic embedded system for two series FACTS devices, namely SSSC and IPFC, to evade the numerical issues faced by traditional iterative methods. The developed embedded systems and white germ solutions are investigated along-with their recursive relationships.

Installation cost estimation of IPFC for Power Loss Reduction in Transmission lines using Firefly Algorithm

Firefly algorithm is proposed in this article for placement of Interline power flow controller (IPFC) to reduce power loss of a transmission line and cost estimation. The IPFC is one of the series FACTS devices. It can control active and reactive power of multiple transmission lines. Power loss reduction, improvement of efficiency of the transmission line and enhancement of voltage profile are major issues in the power transmission system. The average power loss in the system is taken as the objective function with various constraints and then cost is estimated. The code has been developed in MATLAB (Version 2019) and executed on personal computer. The proposed algorithms has been tested on IEEE 5 bus system and the results are presented. It is noticed that the proposed algorithm provides best results in terms of power loss and installation cost with less computational time.

Contingency Analysis for Improved Power System Stability of the Nigerian 330 Kv, 48-Bus System Using Series Facts Controllers

Stressed electric network, either due to increased loading because of system expansion, or due to extreme contingencies, often result in voltage limit violations and overload of lines leading to extreme degradation in the system's damping torque, metamorphosing into fluctuations and dynamic instability. This paper employs two series, Flexible Alternating Current Transmission System (FACTS) controllers; Static Synchronous Series Compensator (SSSC) and Thyristor Controlled Series Compensator (TCSC) to investigate the system responses during line outages for dynamic stability improvement. The commercial version of Power System Analysis Toolbox (PSAT) was used to model the Nigerian 48-bus power system network with simulation of line outages using breakers on lines 6-8 (Oshogbo to Ikeja West transmission stations) and 35-39 (Ugwuaji to Ikot Ekpene transmission stations). SSSC and TCSC were optimally positioned on line 21-28 close to bus 21 (Jos transmission station) after continuation power flow simulation and computation of voltage sensitivity factor of all the load buses. Results show that the two FACTS controllers effectively improved the system stability by reducing the rotor angle and speed and by damping the post outage oscillations of the bus voltage and real power.

Power System Security with Contingency Technique by using SSSC & UPFC

Now days’ electrical power requirement has enlarged expanding as expansion & restructuring of electrical power system (PS) for generation & transmission in power sector is critically limited due to current resources & environmental circumstances. As outcome, approximately of corridors of power transmission overhead lines are greatly loaded & congested. Also major issue of power system voltage stability becomes power transfer restricted and capability issue. A Modern power electronics technology FATCS considered device Static Synchronous Series Compensator (SSSC) is VSC demanded series FACTS equipment. Unified power flow controller (UPFC) is to manage power flow (PF), voltage magnitude & phase angle. In this research paper suggested to maintain voltage magnitude as well as PF of faulty lines. The consequence of mutation of PS parameters like voltage, phase angle, active power, reactive power, & overall power factor with & without SSSC & UPFC have also incorporated. Assessment of PS safety is essential in society to expand customs to sustain system functions when one or more components fail. A PS is "secure" when it can defy loss of one or more ingredients & still go on working without major problems. The Contingency event investigation technique is taken to identify electrical node PF in faulty transmission lines (TL). The Performance of PS has been tested on IEEE 14-Bus System.

Power System Security by FACTS Devices using GA

Now daily's electrical power necessity has expanded exponentially while the development and rebuilding of the electrical power framework for age and transmission in the power segment has been basically restricted because of present assets and natural conditions. Accordingly, roughly of the halls of power transmission overhead lines are intensely stacked and clogged. Additionally the serious issue of power framework voltage dependability turns into a power move constraining and capacity factor. A Modern power electronics innovation FATCS based gadget Static Synchronous Series Compensator (SSSC) is a VSC based series FACTS gadget. Bound together power flow controller (UPFC) is to control power flow, voltage magnitude, and phase point. In this examination paper proposed to keep up the voltage magnitude just as power flow of broken lines. The result of change of the power framework parameters, for example, voltage, phase point, dynamic power, responsive power, and in general power factor with and without SSSC and UPFC have additionally been consolidated. Assessment of power framework security is important in the public arena to create approaches to keep up framework activity when at least one segments come up short. A power framework is "secure" when it can resist the loss of at least one fixings and still continue working without serious issues. The Contingency occasion examination strategy is taken to recognize electrical hub power flow in the flawed transmission lines. The Performance of power framework is checked on IEEE 14-Bus System.

Analysis of Radial Distribution Systems with FACTS Devices Using a Fast Line Flow-Based Algorithm

The electrical energy produced at the generating station is conveyed to the consumers through a network of transmission and distribution systems. It is often difficult to draw a line between the transmission and distribution systems of a large power system. It is impossible to distinguish the two merely by their voltage because what was considered as a high voltage because what was considered as a high voltage a few years ago is now considered as a low voltage. In general, distribution system is that part of power system which distributes power to the consumers for utilization. Analysis of radial distribution systems with embedded series FACTS devices is facilitated by a formulation of power flow equations with bus voltage magnitudes and line flows as independent variables The line flow-based (LFB) formulation is shown to provide easy implementation with multiple series FACTS devices in the system and enable direct evaluation of the FACTS device ratings. Keywords: FACTS, LFB, Radial distribution system DOI : 10.7176/NCS/10-01 Publication date :July 31 st 2019

Optimal Allocation of Series FACTS Devices Under High Penetration of Wind Power Within a Market Environment

Series FACTS devices are one of the key enablers for very high penetration of renewables due to their capabilities in continuously controlling power flows on transmission lines. This paper proposes a bilevel optimization model to optimally locate variable series reactor (VSR) and phase shifting transformer (PST) in the transmission network considering high penetration of wind power. The upper level problem seeks to minimize the \textcolor{black}{investment cost} on series FACTS, the cost of wind power curtailment and possible load shedding. The lower level problems capture the market clearing under different operating scenarios. Due to the poor scalability of $B\theta$ formulation, the \textsl{shift factor} structure of FACTS allocation is derived. A customized reformulation and decomposition algorithm is designed and implemented to solve the proposed bilevel model with binary variables in both upper and lower levels. Detailed numerical results based on 118-bus system demonstrate the efficient performance of the proposed planning model and the important role of series FACTS for facilitating the integration of wind power.

The Interdependence Between Transmission Switching and Variable-Impedance Series FACTS Devices

High congestion costs and new congestion patterns, formed by intermittent renewable generation, demand for more efficient utilization of the transmission system. Transmission switching (TS) and variable-impedance series FACTS devices are two technologies that provide such efficiency gains through controlling the power flows. As the system operators begin to utilize these tools, it is essential to understand the interdependence between them at various stages, such as planning and operation. This paper develops an optimal power flow framework that incorporates both FACTS and TS to study the link between the two power flow control technologies. The simulation results on an RTS 96-bus system suggest that: 1) substantial economic savings can be achieved through utilization of both TS and FACTS, beyond the independent capabilities of each technology; 2) performing TS actions affect the optimal location and set point of FACTS devices; and 3) operation of FACTS devices affect the location and frequency of TS actions. It is, thus, essential to acknowledge the interdependence between the two technologies both at the planning and operation stage. Failure to do so will lead to economic inefficiencies that can be avoided through co-optimization of generation dispatch, TS, and FACTS.

Optimal allocation of series FACTS devices in large‐scale systems

Series FACTS devices, such as the variable series reactor (VSR), have the ability to continuously regulate the transmission line reactance so as to control power flow. This paper presents a new approach to optimally locating such devices in the transmission network considering multiple operating states and contingencies. To investigate optimal investment, a single target year planning with three different load patterns is considered. The transmission contingencies may occur under any of the three load conditions and the coupling constraints between base case and contingencies are included. A reformulation technique transforms the original mixed integer nonlinear programming (MINLP) model into mixed integer linear programing (MILP) model. To further relieve the computational burden and enable the planning model to be directly applied to practical large scale systems, a two phase decomposition algorithm is introduced. Detailed numerical simulation results on IEEE 118-bus system and the Polish 2383-bus system illustrate the efficient performance of the proposed algorithm.