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Transmission congestion is one of the major drawbacks of deregulated power system. Due to increase in load demand, generation increases, but capacity of transmission line is limited, and transmission lines carry power more than its rated capacity, as a result congestion occurs. Congestion management in deregulated power system is a challenging and tough task which can be achieved by introducing one or more Distributed Generators (DG) at optimal location. Optimal location and sizing of DGs is very important for maximizing the social welfare function which is profit to both the producers and consumer of electricity. In this paper hourly congestion management is proposed. It manages the network congestion by optimal placement and sizing of DG in ‘24 h’ time frame. Transmission Congestion Rent (TCR) is used to find the optimal location for DG placement whereas hybrid Differential Evolution (DE) and Particle Swarm Optimization (PSO) technique is used for finding optimal size of DG. In this work, Solar PV along with Energy Storage System (ESS) is utilized as Distributed Energy Storage System (DESS). ESS along with DG is used to store surplus energy during off-load period which will be utilized at peak load thereby enhancing the overall efficiency of the system. 24 h solar irradiance and temperature data of Delhi is taken to mathematically model the power generated from Solar PV. Results obtained with hybrid optimization technique are compared with PSO based optimization. It is observed that hybrid optimization technique outperforms the PSO optimization technique in managing resources and congestion problem in the network for the ‘24 h’ time frame. Proposed work has been carried out on IEEE 30 bus test system.

When an energetic primary conductor comes into contact with a quasi-insulating surface, such as a tree, equipment, or structure or it falls to the ground, the occurrence of the high impedance fault becomes quite high. The importance of these previously unnoticeable flaws is that they pose a significant threat to public safety as well as the risk of ignition by arcing fire. The high impedance failure is categorized by a sufficiently high impedance that traditional safety, such as fuses and current relays, does not detect it. Unlike short circuits with low impedance, which involves relatively large fault currents and are easily detectable by conventional over-current protection, these HIFs constitute a small threat to the power system equipment damage. High impedance failures generate current rates approximately in the range from 0 to 85 Amperes. Typically, a HIF shows flashing and arcing at the point of contact. In this paper, high impedance fault is modelled in the MATLAB/Simulink environment and are classified using discrete wavelet transform to implement proper safety scheme in the distribution system.

This paper presents the fuzzy logic system (FLS) for the classification and detection of three-phase fault that occurs in the distributed power system network. An 11 kV, 50 Hz three-phase three-wire power system distributed network model is designed in MATLAB/Simulink environment and various faults such as Normal, Line to Ground (LG), Line to Line (LL) to Ground (LLG), and Line to Line to Line to Ground (LLLG) have been applied to study the performance of distribution system. Based on the results of the simulation, it has been analyzed that the proposed fuzzy logic system correctly classifies and detects the various types of the fault.

Protection is an utmost important part of a power system as it helps in its proper and safe operation. In order to comprehend the complexity of it, modern simulation tools can be used as an active learning tool along with classroom teaching. The simulation tools considerably improve the level of understanding of the theoretical concepts without expensive lab-setups. This paper presents a methodical approach using simulation tool PSCAD to enhance the teaching–learning experience of transmission line protection using distance relay with the auto-recloser feature. The response of the protection scheme is studied and analyzed when the temporary and permanent fault occurs in the system.

Transmission congestion is one of the prevailing limitation present in the current scenario employing the restructured power system. It is the scarcity of transmission capacity to deliver the power to all the prioritized load transactions at transmission and distribution end. Several other issues rather than obstruction to continuous power flow have risen due to the congested network such as market inefficiency, market power and security. Transmission line parameters will be exceeded beyond its stability limits effecting voltage and thermal limits of the entire transmission system. Congestion management is a methodology that helps us to resolve the issues prevailing in the network owing to restriction in path of power flow through transmission lines having certain power flow limits. Management of power flow congestion in huge electric power system remains a challenging and tough task which can be achieved by introducing Distributed Energy Storage System (DESS) in the congested line. Optimized definite location and size of DESSs are necessary before placing it for maximizing the social welfare function which is nothing but profit to both the producers and consumer of electricity. Consequently, in this work, congestion management for ‘24 h’ time frame has been proposed. It manages the network congestion by selecting preeminent site and size of DESS with in ‘24 h’ time frame. Transmission Congestion Rent (TCR) is used to find the preeminent site for Distributed Generator (DG) whereas hybrid combination of Differential Evolution (DE) and Particle Swarm Optimization (PSO) technique for optimal DG size. In this work, Solar PV along with Energy Storage System (ESS) is utilized as Distributed Energy Storage System (DESS). ESS along with DG is used to store surplus energy during off-load period which will be utilized at peak load thereby enhancing the overall efficiency of the system. Real 24 h’ solar irradiance and temperature data of Delhi are taken to mathematically model the power generated from Solar PV. The suggested methodology is verified on standard IEEE 30 bus system with certain modifications. At the meantime, 24 h’ demand data is created by considering 25% load of the original IEEE 30 bus demand data. The efficacy of proposed methodology is assessed by matching the proposed system results with PSO technique based system results as available in the literature. After analysis it is observed that hybrid optimization technique outperforms the PSO optimization technique in managing resources and congestion problem in the network for the ‘24 h’ time frame.

Voltage instability is a major problem in power system it seldom results in voltage collapse and blackout. FACTS devices can be used to maintain voltage stability by controlling active and reactive power and increase voltage stability margin. Optimal location of these devices is also an important issue. In this paper static var compensator (SVC) is used to improve voltage stability. Optimal location of SVC is found by continuation power flow and by finding fast voltage stability index. SVC is placed at optimal location and its effect on improving voltage stability, loadability limit and reducing power losses have been studied under normal as well as contingency conditions. Two types of contingencies are considered, transmission line (N − 1) contingency and generator outage contingency. The proposed work is tested in IEEE 14 bus test system.

In unbundled electricity market managing transmission congestion is a real challenge for independent system operator. This paper presents placement of thyristor controlled series compensators (TCSC) at optimal location for maintaining voltage stability and mitigating congestion under single line contingency condition. Optimal location is found out by Line voltage stability index calculation. Congested lines are found out under contingency condition (single line outage). Critical contingencies are found out by finding performance index. Effect of placement of TCSC under critical contingency can be observed. TCSC is a member of Flexible AC Transmission Systems devices can reduce power loss in overloaded transmission lines, have ability to increase loadability, reduce system loss and maintains stability of power systems. Work is carried out on IEEE 14 bus test system using MATLAB.

In the deregulated power system congestion of transmission network is a key challenge. Any attempt to operate transmission system beyond its line limits leads to congestion. By use of FACTS devices, the power transfer capability of network increases & reactive power compensation is done thereby improving the power system stability and network power quality. This paper presents the optimal placement of Thyristor controlled series compensators (TCSC) to avoid congestion in the transmission network. The optimal placement is figured out by factors like line utilisation factor (LUF), line loading, voltage profile at each bus & real and reactive power losses between buses. An algorithm is presented for finding the optimal location for placing TCSC. The reactance model of TCSC is considered to hike the power capabilities of the line. The potency of the model is tested on IEEE 24-bus system with the standard data using MATLAB-PSAT Simulink.

In the deregulated power system market, congestion management is one of significant technical issues. Congestion management demands for decrease in load in a particular line, installation of flexible AC transmission system (FACTS) devices in transmission line for reliability and the addition of new renewable generation unit. Various new technologies have been developed so far to mitigate congestion within the network without construction of any new line. This paper presents an idea of mitigating congestion by using Smart Wire (SW) in series. SW series module operates whenever congestion is detected and during normal condition, the smart wire circuitry is bypassed. This technology supports the efficacy of the system by decreasing relevant losses also. Proposed system utilises 15 bus IEEE system in MATLAB/Simulink to demonstrate the working of smart wire, and the results are formulated graphically.

In the current scenario of deregulated power system congestion in the network is one of the critical issues, which need to be resolved for better economic and system efficiency. Several measures have been adopted to relieve the system from congestion for maximization of social benefit. Fuel cost minimization is considered as the key factor for social welfare maximization, which provides benefits to both buyer and consumer of electricity. The fuel cost minimization for power system is achieved based on many parameters one of them being generator allocation. This paper uses GA-based optimization algorithm to obtain optimal generator allocation to find the best fit having minimum fuel cost. The proposed approach for fuel cost minimization is tested on IEEE 14 bus standard system.

Transmission congestion occurs in a power system due to increase in load demand. This mainly occurs in restructured power system because of restrictions of transmission line capacity. Due to this power system does not remain in secure condition. Ranking of contingency is done using performance index and critical contingency is found. In this paper, placement of multiple TCSCs for reducing transmission line congestion under single line critical contingency condition is done. Optimal location for placement of TCSCs is found out by using sensitivity analysis. By placing two TCSCs, there is reduction in line loading, improvement in voltage profile and reduction in reactive power loss, thus keeping power system in secure condition under critical contingency. Proposed work is carried out on IEEE 14 bus test system using MATLAB.

Transmission line efficiency is one of the major issues to be addressed in the heavily stressed electrical power system. It is a challenge to improve the overall power transfer capability along with considering system constraints that influences the better operational outcome of the power system at minimal cost of expansion. This problem can be overcome by having controllable power flow between tielines. This paper increment transmission line efficiency issueby installation of SmartWire Modules (SWM)and Controllable Network Transformers (CNT)in the transmission line when it is over loaded. Smart wire is a single turn transformer device which can improve the transmission capacity of transmission lines. Whereascontrollable network transformer is a smart transformer device connected in between the tie lines to provide more accurate power flow control.

The rapid increase in demand of electricity led to many challenges in transmission and distribution network in power systems. Out of which one of major problem is congested transmission lines. Earlier various FACTS devices were introduced to manage the congestion in lines. But they suffer for cost as well as reliability issues. To suppress these issues this paper introduces a device called Smart Wire that is connected in transmission lines. This smart wire limits the flow of current in transmission lines hence protects the lines from being congested. The operation of smart wire is implemented on IEEE-5 bus system. The results obtained have shown tremendous improvement of congestion from the transmission network.

In this paper placement of thyristor controlled series compensators (TCSC) at optimal location of a power system for maintaining voltage stability, improving transmission efficiency, steady state stability limit and mitigating congestion under single line critical contingency condition is discussed. Optimal location is found out by line voltage stability index and sensitivity analysis. Performance index (PI) is used for finding critical contingency. Under critical contingency condition which is single line outage in this case, congested transmission lines are found. TCSC is a FACTS device which can reduce power loss in overloaded transmission lines, increase loadability, reduce system loss and maintain stability of power systems. This work has been tested on IEEE 14 bus test system using MATLAB.

Voltage collapse is the possible outcome of voltage instability. Voltage collapse occurs when the transmission lines are operating very close to their maximum capacity limits. This paper focuses on the usefulness of two voltage stability indices to find out the weak bus so that the appropriate measures can be taken in advance to avoid voltage collapse. In this paper, WSCC 3 Machine, nine bus test system has been considered and comparison of different voltage stability indices is done to predict voltage collapse.

Major problem of heavily loaded system is, transmission networks are operating close to their limit which causes increase in stress on transmission lines. This problem was solved by the addition of isolated and individually controlled devices such as FACTS to the existing networks. This paper focuses on FACTS device-TCSC (Thyristor Controlled Series Capacitor) and its optimal location in the power system network. To decide optimal location of TCSC sensitivity factor methods and stability indices are used. These methods are applied on IEEE-14 bus system and its power flow analysis is done using PSAT (Power System Analysis Tool Box) software. Reactive and real power loss sensitivities, and line voltage stability indexes are calculated for each line and power flow results are compared with and without TCSC in sensitive and critical lines.

Power flow study is the initial step which provides voltage magnitudes, phase angles, active and reactive power flows at respective buses under normal operating conditions. It helps in analyzing the current state of the power system and effective alternative options for expanding the existing system in order to meet with the increasing load demand. Contingency Analysis is also a major part of study for reliable and planned operation of power system. It is very significant function in modern Energy Management Systems. The objective of contingency analysis is to give operator the information about the static security. There are several factors which may lead to the contingency in power system, for example line outage, transformer outage, generator outage and overloads resulting the extreme situations such as voltage collapse, over loads in other branches and/or sudden system voltage rise or drop. Contingency analysis is used to calculate parameters violations. In this paper, maximum loading parameter is calculated and contingency status of Western System Coordinating Council 3 Machine, 9 Bus test system is done using PSAT toolbox in MATLAB.