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Voltage quality is an essential requirement in the operation of electricity distribution systems. At consumer busbars, the deviation from the nominal voltage has specific ranges, prescribed in technical regulations. A widely chosen voltage correction approach is to use reactive power compensation. Capacitor banks are used for this purpose in highly loaded networks, but their placement and sizing require...
The optimal capacitor allocation in electricity distribution networks (EDN) plays a meaningful role in voltage profile improvement, power factor amelioration and also power losses minimization. This work presents two comprehensive optimization algorithms based on metaheuristics as a comparison to solve the capacitor allocation problem in modern distribution networks. Thus, the problem of optimal capacitor...
An important requirement of a distribution network is that the voltage variations at the end user terminals should be as low as possible. This paper investigates a particular approach that highlights the influences which the connection of shunt capacitors may have over the solutions for voltage control in distribution networks. The problem of optimal capacitor allocation for the minimization of bus...
Capacitor banks (CBs) are used for reactive power compensation in electricity distribution systems. In order to achieve the best effect, CBs placement requires optimization. Metaheuristic computational intelligence algorithms are methods widely used in the literature for this purpose. This paper presents a parallel Particle Swarm Optimization algorithm for bus voltage optimization. The results of...
The power distribution networks supply nonlinear consumers which causes a distorted and unbalanced state. A repercussion of these states is represented by the increase of active power losses. Even if the symmetrical sinusoidal state is initially considered for the power losses, in reality this often leads to power lines overloading, especially for the neutral. The existing method for power losses...
Static VAR compensation is used as a fast response mechanism for dynamic voltage regulation in transmission grids. SVCs use electronically controlled shunt capacitors and reactors to inject or draw reactive power from the grid. This paper investigates the performance of standard Particle Swarm Optimization and Genetic Algorithms and proposes a hybrid GA-PSO approach for choosing the optimal buses...
The basic requirements for a good distribution system are good voltage profile, availability of power on demand and reliability. Capacitors are commonly used to provide the reactive power compensation in distribution systems. This paper investigates a particular approach that highlights the influences which the connection of reactive power sources may have over the solutions for voltage control in...
In this paper, an algorithm aiming for reliability in wireless sensor networks (WSN) will be discussed. Reliability optimization in WSN is obviously an important problem, because a more reliable network can secure a correct, durable, and complete communication. Power consumption optimization in WSN is highly necessary in order to have a reliable sensor network because consumption of power by WSN is...
This paper presents a medium term load forecasting methodology based on a mixed statistical computational intelligence model. The methodology can be used by any entity (such as transmission and distribution operators, electricity suppliers or energy managers) interested in planning different activities with electricity. The methodology produces daily load profiles forecasts for all the 365 days of...
The paper presents a self-organization based integrated model for customer classification and load profiling in distribution systems. The consumer classification in consumption classes characterized by typical load profiles is made using information provided by Smart Meters. For determination of the consumption classes, every customer is characterized by the following primary information: daily (monthly)...
Since the development of the Multilayer Perceptron, many types of artificial neural networks (ANNs) have emerged, each having best performances in solving particular types of problems. Current research developments focus on hybrid neural models, which combine neural and symbolic computation elements. In power engineering, ANNs are used today in a variety of applications, including optimization, approximation,...
State estimation is used currently in wide area electrical systems for real time analysis. Studies have shown that in HV transmission networks, where system-wide synchronized phasor measurement units are installed, voltage angle measurements can be included in the input measurements data set, with the result of improving the estimation precision. The authors developed in previous papers a SE algorithm...
The main objective of this paper is the enhancement of power system stability by using complex structure of Power System Stabilizers (PSS) in the voltage regulation loop of synchronous generators. The PSS uses multiple local and remote input signals. The remote signals are provided by Phasor Measurement Units (PMU) and measure the frequency at different buses and active power flows on different tie-lines...
A fundamental component of a smart grid is transmission and distribution system monitoring and control. Accurate load, power flow and voltage estimation is required for real time generation capacity dispatching and congestion management in wide area power systems or in networks with distributed generation. In electrical networks, bus voltage levels, load, generation and branch power flows are interdependent,...
The basic function of a power system is to provide an adequate electrical supply to its customers as economically as possible with reasonable level of reliability. Evaluating the reliability of a power system is a complex process and the work with the actual methods is difficult. Reliability studies require information about the history of the network components' behaviour, about the economic consequences...
While common estimation algorithms use as input data rated equipment parameters, the actual parameters of a three phase line will change with the load amount and unbalance degree, and weather conditions. This paper presents a method for estimating the actual MV overhead distribution line parameters such as resistance, reactance, shunt conductance and susceptance, using synchronous voltage and current...
This paper approaches a multi-objective non-conflicting optimization problem that aims to find the loading of local generators (DG) and the most appropriate DR strategy applied to some important customers in the network, to simultaneously optimize two objective functions. A combined method between differential evolution (DE) and analytic hierarchy process (AHP) is used in order to find the solution...
This paper studies the possibility to apply the approximation power of the MLP ANN in developing an alternative method for computing the load flow when the configuration of the system does not change. If the bus admittance matrix remains the same, the bus voltages are affected only by the changes of the bus active and reactive loads, in a non-linear and predictable variation. If the network is trained...
The Static state estimation is widely used in power systems for real time monitoring and analysis. Standard methods, such as the weighted least squares (WLS) algorithm, require the computation of bus admittance and Jacobian matrices and the solution is found in an iterative process. This paper presents an alternative for the classic state estimation (SE) algorithms, which uses a multilayer perceptron...
In the framework of the deregulated electricity markets, the way in which old local grids operate has changed. The degree of interconnection increased, and local networks became parts of wide area power systems. As part of the need to upgrade the existing networks in order to cope with the new operating conditions, the concept of smart grids was proposed. A part of such a smart grid is a real time...
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