Akanksha Mishra

Congestion management of power system with interline power flow controller using disparity line utilization factor and multi-objective differential evolution

The restructuring of the electric power market has led to complex power transmission congestion problems. Additionally, scheduled power flows in the transmission line, as well as spontaneous power exchanges have also risen sharply in recent years. The proper placement of IPFC can improve the transmission line congestion problem to a great extent. This paper proposes a disparity line utilization factor (DLUF) for the optimal placement of IPFC to control the congestion in transmission lines. DLUF determines the difference between the percentages of Mega Volt Ampere utilization of each line connected to the same bus. The IPFC is placed in the lines with maximum DLUF. A multiobjective function consisting of reduction of active power loss, minimization of total voltage deviations, minimization of security margin and minimization of installed IPFC capacity is considered for the optimal tuning of IPFC using differential evolution algorithm. The proposed method is implemented for IEEE-30 bus test system under different loading conditions and the results are presented and analyzed to establish the effectiveness on the reduction of congestion.

A Fast Contingency Management Approach with Optimal Placement and Tuning of Interline Power Flow Controller Using Differential Evolution Algorithm

Abstract In the traditional approach of steady-state contingency screening, each line is removed sequentially and its effect on the system is studied, while only some contingencies may cause certain lines to become severe. This article presents an approach for fast contingency ranking in steady-state, based on the selection of a limited number of important buses. A composite severity index based placement of interline power flow controller and tuning using differential evolution for IEEE 14- and 30-bus systems has also been proposed. The composite severity index is a combination of line utilization factor and fast voltage stability index. All the lines connected to the important buses only are sequentially considered for line outage and the most severe line corresponding to each outage is ranked on the basis of composite severity index. An interline power flow controller is optimally placed and tuned to improve the system post-contingency condition. Differential evolution has been used to tune the device for a multi-objective function. The load on the system is increased to test the performance of the interline power flow controller under highly stressed conditions.

A risk of severity based scheme for optimal placement of interline power flow controller using composite index

Due to massive increase in the power transactions due to restructuring, the stress in transmission lines has increased largely and severity assessment is very essential. Contingency assessment of a power system predicts the effect of outages in transmission lines and generator units. In this paper, contingency ranking of the lines has been done using composite severity index. A risk-based strategy has been adopted for the placement of interline power flow converter (IPFC). From the list of the severe lines obtained, IPFC is placed on the line which has highest possibility of severity during the occurrence for different outages. To verify the proposed methodology, it is implemented on IEEE 30 and Indian Utility 62 bus systems. The load on the bus with highest load is further increased gradually up to the critical value and the results have been presented and analysed to ascertain the effectiveness of IPFC for contingency management.

Composite severity contingency distribution index based contingency management of power system

Secured and uninterrupted operation of the power systems has become a great challenge. The load on the practical power systems vary through the day, month and year. Thus making the task of the power system engineers much more complicated. In this paper, a novel index, namely, composite severity contingency distribution index (CSCDI) has been proposed in order to find the severe-most line of the system under contingency condition in real time scenario. Contingency analysis for each hour load of the IEEE 30 bus system has been performed. CSCDI has been calculated for each line of the system and the result obtained indicates the stress on the lines due to contingency for varied load throughout the day. An IPFC has been optimally placed to improve the post-contingency condition. The device has further been tuned for a multi-objective function using differential evolution algorithm. The results obtained have been presented and analyzed to emphasize on the advantages of IPFC for post-contingency management in a real time framework.

Harmony Search Algorithm Based Optimal Tuning of Interline Power Flow Controller for Congestion Management

With rapid increase in private power producers to meet the increasing power demand, results in the congestion problem. As the power transfer is increasing the operation of power systems is becoming difficult due to higher scheduled and unscheduled power flows. Interline Power Flow Converter (IPFC) is a most flexible device and effective in reducing the congestion problem. In this paper line utilization factor (LUF) is used for finding the best location to place the IPFC. The Harmony Search (HS) Algorithm is used for proper tuning of IPFC for a multi objective function which reduces active power loss, total voltage deviations, security margin and the capacity of installed IPFC of installed IPFC capacity. Simulation is carried out on IEEE-30 bus test system and the results are presented and analyzed to verify the proposed method.

Composite Severity Indices Based Contingency Management of Power System: A Comparative Study

Severity assessment of transmission lines is a very important aspect of contingency analysis of a power system. Thereafter, a proper solution needs to be provided to ensure a secured power supply. In this paper, rapid contingency ranking technique (RCRT) has been introduced for the contingency assessment of a power system. Several composite indices have been designed by forming different combinations of line overload indices and voltage stability indices and the results have been compared. Deterministic and probabilistic approach have been used for the placement of IPFC and the results have been compared. While, the probability approach protects the system against most of the contingencies, the deterministic approach protects the system against the severe-most contingency. Thereafter, the IPFC is tuned using the differential evolution method. A multi-objective function has been formulated for tuning the device. The use of IPFC to overcome the post-contingency problems has been reinforced by implementing the proposed strategy on an IEEE 57 bus system.

A line utilization contingency distribution index based secured operation of power system

Abstract The practical power systems undergo variable load throughout the year. Maintaining security and reliability in operation of these structures in such a vulnerable scenario is a huge challenge. In this paper, a line utilisation contingency distribution index (LUCDI) has been proposed for obtaining the weakest line of the real-time power system in cases of contingency. The contingency analysis has been executed for every hour load of the IEEE 30-bus system. The LUCDI has been computed for every transmission line of the power system for the severe-most outage, which specifies the stress on the transmission lines as a result of contingency for a real-time load. An interline power flow controller (IPFC) has been positioned and tuned to recover the system from the post-contingency condition. A function with multiple objectives has been used for tuning the IPFC using differential evolution and results have been evaluated to highlight the benefits of an IPFC for management of post-contingency condition in a real-time context.

Optimal Utilization of IPFC for Congestion Management Using Disparity Line Utilization Factor and Cuckoo Search Algorithm

Recently, due to adoption of power reforms there is a marked increase of contracted power that flows in the transmission line and the spontaneous power exchanges leading to complex power transmission congestion problems. Appearance of FACTS devices specifically IPFC has opened up new opportunities to overcome the congestion problem by increasing the system loadability. Proper placement and tuning of IPFC in this respect is very important for maximum utilization of its benefits. This paper proposes a Disparity Line Utilization Factor (DLUF) for the optimal placement of IPFC to control the congestion in transmission lines. DLUF determines the difference between the percentage MVA utilization of each line connected to the same bus. The IPFC is placed in the lines with maximum DLUF. The multi objective function consisting of the reduction of active power loss, minimization of total voltage deviations, and minimization of security margin with the usage of minimum value of installed IPFC is considered for the optimal tuning of IPFC using Cuckoo Search. The proposed method is implemented for IEEE-30 bus test system under different loading conditions and the results are presented and analyzed to ascertain the effectiveness for the reduction of congestion.