Optimal Placement Of Shunt Capacitors Research Articles

Time-series quasi-dynamic load flow analysis with seasonal load variation to resolve energy nexus for a practical distribution network in Puducherry smart grid system incorporating harmonic analysis and mitigation

Time-series quasi-dynamic load flow analysis is an important methodology to estimate the voltage profiles across various nodes in modern distribution networks. This paper describes the necessity of time-series load flow analysis (LFA) for a real-time power distribution network in Puducherry smart grid system by considering seasonal load variations in the union territory of Puducherry, India to obtain optimal performance. In this study, this load flow analysis has been applied to test systems such as IEEE 69, IEEE 37, IEEE 34 and the Indian utility 29 node distribution network (IU29NDN) in Puducherry smart grid system with unbalanced load patterns and energy sources in close proximity. Modified Decision Making (MDM) algorithm is proposed in this paper to improve voltage profiles with in distribution networks by choosing the size and location of solar photovoltaic (SPV) systems. The variations in the node voltages, real power, and reactive power flows are estimated for distribution networks subjected to seasonal load variations by quasi-dynamic load flow simulations conducted over a period of 24 h with 15-minute step size. Furthermore, a harmonic power flow is illustrated and extended to mitigate the harmonics by optimal placement of shunt capacitors (SCs) in all the test systems by incorporating MDM algorithm.

Optimal capacitor placement in northern region of Bangladesh transmission network for voltage profile improvement

This paper solves the problem of optimal placement of shunt capacitors in the northern region of Bangladesh transmission network. During network augmentation event like very high inductive reactive load condition, the weakened voltage profile of the buses can be compensated by optimum allocation of the capacitor banks. In this regard, the aim of this problem is to minimise the costs associated with capacitor banks, transmission system losses and voltage profile improvement whilst satisfying various constraints. Mixed integer linear programming method is introduced for the discrete optimisation problem of placing capacitors in transmission system for cost minimisation and voltage profile improvement. In this proposed formulation, sensitivity dependent voltage magnitude is taken into account for the selection of candidate buses. It is also shown that voltage profile is linearly dependent on reactive load. Therefore, load modelling is done carefully to get a more realistic image of the overall outcomes. The proposed methodology yields integer number of capacitors of particular sizes to be placed on best suited buses. In addition, the proposed approach is applied to IEEE 39 bus system and 33 bus real transmission system of northern region of Bangladesh power system Furthermore, a thorough performance comparison with an existing state-of-the-art capacitor placement method is also performed for validation. The simulation results demonstrate that the proposed methodology is capable of producing optimised solution while successfully mitigating the low voltage issue. Moreover, the proposed approach shows enhanced voltage profile of the buses at a reduced reactive support size than the existing approach.

Multiobjective hybrid evolutionary approach for optimal planning of shunt capacitors in radial distribution systems with load models

Abstract This article proposes a novel hybrid heuristic search algorithm based on Harmony search and particle artificial bee colony algorithm (HSA-PABC) for shunt capacitor placement problem. The objective function is framed to minimize power loss and to maximize voltage stability. To search for the optimal location of shunt capacitors, the combinatorial use of loss sensitivity factor and hybrid HSA-PABC algorithm is utilized. In this paper, different types of voltage dependent load models are taken into consideration to investigate their influence on the active power loss and voltage stability of the RDN. Simulation results shows that the voltage dependent load models lead to completely different solutions interms of power loss reduction, voltage stability improvement and net annual savings which are the crucial parameters in the decision process of optimal shunt capacitor placement problem. The result outcomes of the proposed hybrid algorithm outperform the results of other heuristic techniques in the literature.

An Analytical Method for Optimal Capacitors Placement from the Inversed Reduced Jacobian Matrix

This paper presents a novel analytical methodology to determine location for optimal shunt capacitor placement in power systems. The new method modifies modal analysis technique and develops new formulation to compute the Reactive Contribution Index (RCI) of each load buses based on the inversed reduced Jacobian matrix. The objective of this study is to achieve the most stable condition as well as to minimize network losses. The proposed method is implemented at the modified IEEE 30-bus Reliability Test System (RTS). The simulation results show the proposed method can provide a solution to the ideal shunt capacitor placement to improve the system's voltage stability.

Reconfiguration and Capacitor Placement of Radial Distribution Systems by Modified Flower Pollination Algorithm

This article proposes a combined methodology for network reconfiguration and optimal placement of shunt capacitors in radial distribution systems to reduce real power loss and enhance bus voltages. The power loss is reduced by network reconfiguration and capacitor placement, which in turn reduces a utility's loss of revenue. To ensure radial structure and avoid islanding of nodes, feasible tie-switch combinations are formed prior to the optimization process using a graph theory based method. The modified flower pollination algorithm uses a flower pollination process, an improved local neighborhood search method, and a dynamic switching probability approach to enhance the global search for optimization. The performance of this approach is tested on standard 33-bus, 69-bus, and 118-bus radial distribution test feeders. Results have been compared with previous methods reported in the literature, indicating the effectiveness of the combinatorial approach in terms of loss reduction, voltage enhancement, and cost saving.

APPLICATION OF BINARY VERSION GSA FOR SHUNT CAPACITOR PLACEMENT IN RADIAL DISTRIBUTION SYSTEM

This paper presents a binary gravitational search algorithm (BGSA) is applied to solve the problem of optimal allotment of Shunt capacitors in radial distribution systems. In this work, total line loss (TLL) and the total voltage deviations (TVD) are to be minimized separately by incorporating optimal placement of shunt capacitors with constraints which include limits on voltage, sizes of installed capacitors. This BGSA is applied on the balanced IEEE 12-Bus distribution network and the results are compared with conventional binary particle swarm optimization (BPSO). --------------------------------------------------------------------***------------------------------------------------------------------

Optimum placement of shunt capacitors in a radial distribution system for substation power factor improvement using fuzzy GA method

Abstract In this work a combination of fuzzy multiobjective and genetic algorithm (GA) based approach is proposed for optimal shunt capacitor placement to improve the substation power factor near unity, reduce the real power loss, and reduce the burden on the substation and to improve the voltage profile of the distribution network. In order to obtain best nodes for capacitor placement, a sensitivity index based on real power loss reduction and voltage profile improvement is considered. In the present work, an attempt is made to make reactive current component drawn by distribution network through substation is nearly zero such that power factor at the substation will be near unity. A fuzzy multiobjective function is formed considering substation reactive current component reduction, real power loss reduction, branch current constraint limit, minimum and maximum voltage limit satisfaction. The fuzzy multiobjective function is maximized using GA for obtaining the optimum sizing of fixed and switched shunt capacitors. Simulation results are shown to demonstrate the advantage of the proposed method compared to optimal shunt capacitor placement based on annual energy savings method.