scholarly journals Real-Time Economic Dispatch by Accommodating Implications of Uncertain Renewable Energy Resources

2019 ◽  
Vol 8 (2S11) ◽  
pp. 2484-2488
Keyword(s):  
Renewable Energy ◽  
Power Systems ◽  
Real Time ◽  
Economic Dispatch ◽  
Standard Test ◽  
Energy Resources ◽  
Renewable Energy Resources ◽  
Economic Implications ◽  
Load Demand ◽  
Net Load

The integration of considerable renewable energy resources in power grids has imposed high variability in the net load demand to be seen by conventional generating stations. The real-time economic dispatch (RTED) of modern power systems must consider minute-to-minute variability in the net load demand on the station during a scheduling interval of 5-15 min. The existing methods therefore may not explicitly handle economic implications of power system. This paper proposes a new method for RTED while fully addressing variability in power generation from renewable energy resources and load demand. The method suggests mean PFs for committed generators by conducting (off-line) economic dispatch for each subinterval of 1 min. Mean PFs are evaluated only once, that is just at the beginning of scheduling interval and will continued throughout the interval. This reduces complexity and dimensionality of the proposed method. The simulation results on a standard test bench validate economic competence of proposed approach over that conventional one.

THE ANALYSIS OF OPERATION MODES OF ENERGY STORES IN AUTONOMOUS HYBRID POWER PLANTS WITH RENEWABLE ENERGY RESOURCES

2018 ◽  
pp. 55-67
Author(s):  
S. G. Obukhov ◽  
I. A. Plotnikov ◽  
V. G. Masolov
Keyword(s):  
Renewable Energy ◽  
Power Systems ◽  
Low Frequency ◽  
Rechargeable Batteries ◽  
Energy Resources ◽  
Renewable Energy Resources ◽  
Hybrid Power ◽  
Operation Modes ◽  
Energy Stores ◽  
Energy Store

The paper presents the results of the comparative analysis of operation modes of an autonomous hybrid power complex with/without the energy store. We offere the technique which defines the power characteristics of the main components of a hybrid power complex: the consumers of the electric power, wind power and photo-electric installations (the last ones have been constructed). The paper establishes that, in order to compensate the seasonal fluctuations of power in autonomous power systems with renewable energy resources, the accumulative devices are required, with a capacity of tens of MWh including devices that are capable to provide energy storage with duration about half a year. This allows abandoning the storage devices for smoothing the seasonal fluctuations in the energy balance.The analysis of operation modes of energy stores has shown that for a stock and delivery of energy on time intervals, lasting several hours, the accumulative devices with rather high values of charging and digit power aren't required. It allows using the lead-acid rechargeable batteries of the deep category for smoothing the daily peaks of surplus and a capacity shortage. Moreover, the analysis of operation modes of energy stores as a part of the hybrid complexes has demonstrated that in charging/digit currents of the energy store the low-frequency and high-frequency pulsations of big amplitude caused by changes of size of output power of the renewable power installations and loading are inevitable. If low-frequency pulsations (the period of tens of minutes) can partially be damped due to the restriction of size of the maximum charging current of rechargeable batteries, then it is essentially impossible to eliminate high-frequency pulsations (the period of tens of seconds) in the power systems with the only store of energy. The paper finds out that the combined energy store having characteristics of the accumulator in the modes of receiving and delivery of power on daily time intervals, and at the same time having properties of the supercondenser in the modes of reception and return of impulses of power on second intervals of time is best suited to requirements of the autonomous power complexes with renewable energy resources.

Optimal Operation of Conventional Power Generation with High Penetration of Renewable Energy using Equilibrium Optimizer Technique

2020 ◽  
Author(s):  
Khaled Nusair ◽  
Lina Alhmoud
Keyword(s):  
Renewable Energy ◽  
Power Systems ◽  
Power Flow ◽  
Optimal Power Flow ◽  
Energy Resources ◽  
Solar Pv ◽  
Objective Functions ◽  
Renewable Energy Resources ◽  
High Penetration ◽  
Bus System

Over the last decades, the energy market around the world has reshaped due to accommodating the high penetration of renewable energy resources. Although renewable energy sources have brought various benefits, including low operation cost of wind and solar PV power plants, and reducing the environmental risks associated with the conventional power resources, they have imposed a wide range of difficulties in power system planning and operation. Naturally, classical optimal power flow (OPF) is a nonlinear problem. Integrating renewable energy resources with conventional thermal power generators escalates the difficulty of the OPF problem due to the uncertain and intermittent nature of these resources. To address the complexity associated with the process of the integration of renewable energy resources into the classical electric power systems, two probability distribution functions (Weibull and lognormal) are used to forecast the voltaic power output of wind and solar photovoltaic, respectively. Optimal power flow, including renewable energy, is formulated as a single-objective and multi-objective problem in which many objective functions are considered, such as minimizing the fuel cost, emission, real power loss, and voltage deviation. Real power generation, bus voltage, load tap changers ratios, and shunt compensators values are optimized under various power systems’ constraints. This paper aims to solve the OPF problem and examines the effect of renewable energy resources on the above-mentioned objective functions. A combined model of wind integrated IEEE 30-bus system, solar PV integrated IEEE 30-bus system, and hybrid wind and solar PV integrated IEEE 30-bus system are performed using the equilibrium optimizer technique (EO) and other five heuristic search methods. A comparison of simulation and statistical results of EO with other optimization techniques showed that EO is more effective and superior.

Sign in / Sign up

Export Citation Format

Share Document