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The virtual inertia J in single-phase synchronverter (SPSV) can be designed specifically to improve system stability. However, J also relates to active power loop (APL) and reactive power loop (RPL) time constants, which restricts the flexibility of control parameters choice and increases the complexity of parameter design process. This paper proposes a method to increase SPSV overall inertia without...
This paper briefly introduces the charging and discharging characteristics of electric vehicles, and calculates the charging and discharging load of electric vehicles by Monte Carlo simulation method. A dynamic scene analysis method is used to deal with the stochastic uncertainty of electric vehicles charging and discharging, and the dynamic neural network is used to predict the load. The paper uses...
The Internet of things (IoT) will make it possible to interconnect and simultaneously control distributed electrical loads. Various technical and regulatory concerns have been raised that IoT-operated loads are being deployed without appropriately considering and systematically addressing potential cyber-security challenges. Hence, one can envision a hypothetical scenario when an ensemble of IoT-controlled...
The increasing penetration of electric vehicles (EVs) will bring great challenges to the secure and economic operation of distribution networks. On the other hand, coordinated charging of EVs can alleviate the adverse impacts of charging loads and even increase the efficiency of distribution network operation. This paper aims at optimally scheduling the daily charging of EVs and the daily on/off switching...
This paper develops coordinated voltage control with high penetration of wind in power distribution systems. In the proposed method, daily schedule of optimal voltage profiles are determined by using optimization technique based on predicted values of load demand and by controlling tap positions of regulators, switched capacitors, and reactive power outputs of the inverters. In this paper, three optimal...
In this paper, the performance of different optimization techniques is evaluated for the estimation of dynamic load model parameters. Two categories of methods are considered: the nonlinear least-squares-based and the population-based. The accuracy of the optimization methods is assessed by applying Monte Carlo simulations using artificially created distorted data. In order to represent different...
One of the biggest threats for the security of power grids are congestion of cross-border lines and congestion in the network itself as result of parallel flows. Nowadays, occurrence of congestion is a result of limited network transfer capacities as a direct consequence of increased power transactions. One of the reasons for cross-border congestions are the unreal cross-border capacities calculations...
The aim of the paper is maximization the consumption of energy generated by RES in distribution system. It is achieved by aggregation of loads and power generating units to common internal grid called power park. In order to maximize consumption of renewable energy, the RES sizing optimization model is used. In order to reflect the intermittency of renewables, they are modelled by generation profiles...
This paper presents a novel approach to determine both the exponential and ZIP load model parameters in electrical power system substations. The proposed approach aims to estimate the polynomial and exponential parameters for active and reactive power loads. Field measurements are obtained from a rigorous testing script to impose sustained voltage variations, and the parameters are estimated by using...
This paper presents an algorithm developed for the optimization of Low Voltage (LV) grids that takes advantage of Distributed Energy Resources (DER) such as storage devices and flexible loads. The proposed approach is based on a multi-temporal Optimal Power Flow (OPF) algorithm that feeds from forecasting tools for load and renewable generation, which means the optimization model looks at a 24-hours...
This paper proposes a risk-based mixed integer quadratically-constrained programming model for the long-term VAr planning problem. Risk aversion is included in the proposed model by means of regret-based optimization to quantify the load shedding risk because of a reactive power deficit. The expected operation and expansion costs of new installed reactive power sources and load shedding risk are jointly...
In order to consider the uncertainty of DG and loads, the interval number is used to describe the uncertainty of the wind speed and loads. The optimal selection and configuration of distributed generators model is established for distribution systems. The largest investment income for independent power producer of DG is taken as the objective function, and interval power flow is introduced to determine...
With the optimization of solar distributed generation (DG), different methods and models are implemented for system improvement. However, the stochastic nature and intermittency of solar power is often neglected. This paper presents an approach in finding the optimal site and size of a solar DG unit in the context of minimizing power loss and improving voltage profile. Uncertainties of the solar irradiance...
This paper demonstrates on the development of weak bus identification method using novel reactive power tracing index for determination and selection on appropriate buses for load shedding purpose. Power tracing principles using downstream looking algorithm is utilized for the development of a novel reactive power tracing index known as LQP_LT. The results obtained from the weak bus identification...
This work presents an optimal reactive power management strategy for the operation of a transmission connected distribution grid with high share of wind power. Main control objective is minimizing reactive power exchange with the overlaying transmission grid. For this purpose, a mixed integer non-linear optimal power flow (MINLP-OPF) problem is formulated utilizing reactive power capabilities of wind...
Inpower systems because of uncertainty of the load curve and transfer of power between various utilities and loads block out situations will be created. In these situations the Flexible AC transmission system (FACTS) controllers play an important role in power system security enhancement. As the capital cost of these controllers is high, these controllers must be placed optimally. FACTS devices can...
A new methodology for distribution network planning considering single contingencies and relocation of switchgear is proposed in this paper. A two-stage optimization methodology is developed, where the first stage solves the investment problem and the second stage focuses on the operational aspects. The novelty of the proposed investment methodology is explicit incorporation of network contingency...
Conservation voltage reduction (CVR), the theory that reducing distribution feeder voltages will result in a reduction in demand, has recently been reintroduced with the aim of improving overall energy efficiency. Although CVR is a simple and cost-effective scheme, reducing voltages may not always be the most beneficial decision in terms of reducing demand. In fact, for certain types of load, reducing...
The emerging smart grid paradigm enables more efficient use of energy through optimizing the local grid operation. Conservation Voltage Reduction (CVR) is an application which aims at reducing the power consumption by decreasing the voltage level. Another important application is the Volt Ampere Reactive (VAR) control which aims at flattening the voltage profile and improving the power factor, which...
Among the many electrical load disaggregation methods, often referred to as Non-Intrusive Load Monitoring techniques, the Additive Factorial Approximate MAP (AFAMAP) algorithm has shown outstanding capabilities and, therefore, it is nowadays regarded as a reference model. In order to achieve more accurate disaggregation results, and to satisfy real life environment requirements, further improvements...
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