Evaluating the effects of renewable and non-renewable DGs on DNEP from the reliability, uncertainty, and operational points of view by employing hybrid GA and OPF

Summary Distribution network expansion planning is one of the most important problems in power systems. Modeling distribution network expansion planning in the presence of distributed generators needs new requirements to model the renewable energies, electricity price, and demand uncertainties. In this paper, 2 risk indices are proposed: (1) If a scenario is flexible, it requires a relatively low investment, introduced as adjustment cost, to attain the efficiency of the optimal solution in other scenarios (ie, flexibility criterion) and (2) if the maximum distance of a solution is minimum from the optimal solution of all scenarios, then the scenario is robust (ie, robustness criterion). The resulted model is a multiobjective mixed‐integer nonlinear problem, which is solved using nondominated sorting improved harmony search algorithm‐II. To obtain the final plan, the fuzzy decision‐making analysis is applied, and to demonstrate the effectiveness of the model, it was applied to 9‐node and 69‐node distribution systems.

Section: Numerical Resultsmentioning

confidence: 99%

Flexible and robust distribution network expansion planning in the presence of distributed generators

Rastgou

Bahramara

Moshtagh

2018

“…Equations 20 and 24 reveal the feedback relation between the block JK and the block consisting of the rest of the power system dynamic components, which can be drawn accordingly in Figure 1. Equation 20 shows the transfer function in the forward path of the close-loop system while Equation 24 demonstrates the transfer function in the feedback path of the close-loop system. Each block has its own voltage components as outputs, and its inputs are composed of its own control variables and the voltage outputs from the other block.…”

Section: Building Feedback Modelmentioning

confidence: 99%

Developing feedback model for power system dynamic sensitivity analysis

Hill

et al. 2017

Summary Since sensitivity analysis provides information on changes of the system dynamics with respect to changes of system parameters, it has been long recognized as an important tool for power system small‐signal stability analysis and controller designs. Sensitivity analysis is now much more important due to all the anticipated changes of future power systems, so more efficient and feasible methods are needed. The current sensitivity analysis methods are either simulation based or eigenvalue based. The eigenvalues and/or the time domain trajectories of the investigated system are solved for scenarios both before and after the parameter changes to evaluate the impacts of these changes on the system dynamics. However, both methods are actually numerically based, so often insufficient in fully revealing system physical characteristics. This paper analyzes the drawbacks of the available methods for analyzing the dynamic impacts of parameter changes in a power system and then develops a feedback‐based model for sensitivity analysis. The model is easier to identify the dynamic interactions of components; meanwhile, it also offers a new perspective on sensitivity analysis from the frequency domain. Case studies of increasing complexity demonstrate fully that the application of the proposed method reveals new insights on power system dynamics that conventional methods could not do.

“…In modern power system grid, renewable energy sources (RES) are giving attractive solutions for the future and further technology advancement is in process to enhance energy generation. [1][2][3][4][5][6] The RES have possibility to play an important role in the modern smart grid technology. The contribution and share of their RES in energy production has significantly increased in the last decade.…”

Section: Introductionmentioning

confidence: 99%

Stochastic evaluation of voltage sag in power system network considering effect of photovoltaic generation

Khatri¹,

Kumar

Bansal

et al. 2018

Summary The present scenario need is to integrate renewable energy sources (RESs) with power grid to address the increasing concerns of environmental issues and energy demand. Apart from renewable energy integration, the quality of power delivered is also important. Among all power quality issues, the most common power quality issue is voltage sag which significantly affects industrial, commercial, and domestic users. This paper estimates the frequency of voltage sag using analytical method. This paper also analyses the change in frequency of occurrence of voltage sag when power system network is integrated with photovoltaic system. This stochastic evaluation of voltage sag is performed for 30‐bus IEEE subtransmission system. The voltage sags are evaluated at various observation buses with and without integration of photovoltaic generation. The numbers of photovoltaic generating plant are increased in order to observe variation in frequency of occurrence of voltage sag. The results are presented in terms of frequency of occurrence of voltage sag and area of vulnerability for transmission network.