scholarly journals A New Transient Frequency Acceptability Margin Based on the Frequency Trajectory

Energies ◽  
2018 ◽  
Vol 12 (1) ◽  
pp. 12
Author(s):  
Ancheng Xue ◽  
Jiehao Cui ◽  
Jiawei Wang ◽  
Joe Chow ◽  
Lei Yue ◽  
...  

When the electric power system is disturbed, the transient frequency deviation may be large and harmful to its stable operation, especially in some small power systems. However, there is a lack of transient frequency acceptability margin (TFAM) which could be directly used by dispatchers. In this paper, a new TFAM is proposed based on the transient frequency acceptability index (TFAI). First, based on the frequency trajectory and the philosophy of “different weights to the different frequency offset levels”, a new TFAI is proposed combined with frequency thresholds and time duration limits. The effectiveness of the TFAI is verified, and the critical acceptable disturbance is determined by using the TFAI. Then, a new TFAM is proposed based on the critical acceptability disturbance. The proposed TFAM can quantitatively describe the distance of the operation point from the critical frequency acceptability point, and distinguish the transient frequency acceptability of different disturbances. Finally, with different simulations, the effectiveness and applicability of the proposed TFAM are verified. The TFAM can be used for disturbances with single-parameter and multiple parameters.

2008 ◽  
Vol 18 (05) ◽  
pp. 1415-1424 ◽  
Author(s):  
SHAO-HUA LI ◽  
HSIAO-DONG CHIANG

A structure-induced bifurcation of nonsmooth nonlinear systems is studied and illustrated on electric power system models. The consequence of structure-induced bifurcation is an immediate instability induced by generator reactive power limits. It is numerically shown that structure-induced bifurcation can occur at both small power systems and large-scale power systems. Without taking the structure-induced bifurcation into account in defining power system operating limits, the resulting operating limits can be overly optimistic.


Mathematics ◽  
2021 ◽  
Vol 9 (13) ◽  
pp. 1474
Author(s):  
Ruben Tapia-Olvera ◽  
Francisco Beltran-Carbajal ◽  
Antonio Valderrabano-Gonzalez ◽  
Omar Aguilar-Mejia

This proposal is aimed to overcome the problem that arises when diverse regulation devices and controlling strategies are involved in electric power systems regulation design. When new devices are included in electric power system after the topology and regulation goals were defined, a new design stage is generally needed to obtain the desired outputs. Moreover, if the initial design is based on a linearized model around an equilibrium point, the new conditions might degrade the whole performance of the system. Our proposal demonstrates that the power system performance can be guaranteed with one design stage when an adequate adaptive scheme is updating some critic controllers’ gains. For large-scale power systems, this feature is illustrated with the use of time domain simulations, showing the dynamic behavior of the significant variables. The transient response is enhanced in terms of maximum overshoot and settling time. This is demonstrated using the deviation between the behavior of some important variables with StatCom, but without or with PSS. A B-Spline neural networks algorithm is used to define the best controllers’ gains to efficiently attenuate low frequency oscillations when a short circuit event is presented. This strategy avoids the parameters and power system model dependency; only a dataset of typical variable measurements is required to achieve the expected behavior. The inclusion of PSS and StatCom with positive interaction, enhances the dynamic performance of the system while illustrating the ability of the strategy in adding different controllers in only one design stage.


2013 ◽  
Vol 2 (4) ◽  
pp. 44-58 ◽  
Author(s):  
E. V. Markova ◽  
I. V. Sidler ◽  
V. V. Trufanov

The first part of the paper is devoted to the problem of optimal control in the area of electric power industry which is described on the basis of a one-sector variant of Glushkov integral model of developing systems. The authors consider the ways uncertain conditions of future electric power system development influence the optimal service life. The results of calculations for the Unified Electric Power System of Russia are presented and analyzed. The second part of the paper deals with the application of Prony method to identification of the Volterra equations in the two-sector models of developing systems. The authors suggest a numerical method for identifying the efficiency function parameters. An illustrative example is given.


2019 ◽  
Vol 24 ◽  
pp. 02012
Author(s):  
Yury Shornikov ◽  
Evgeny Popov

Transients in electric power systems are of great interest to power engineers when designing a new or maintaining an existing system. The paper deals with using hybrid system theory for modeling and simulation of an electric power system with controllers. The presented technique is rather convenient and recommended as mathematical models of transients in electric power systems with controllers in general contain both continuous and discrete components. The modeling and simulation were carried out in the modeling and simulation environment ISMA, which is briefly presented in the paper.


Energies ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 418 ◽  
Author(s):  
Gangjun Gong ◽  
Zhening Zhang ◽  
Xinyu Zhang ◽  
Nawaraj Kumar Mahato ◽  
Lin Liu ◽  
...  

With the integration of highly permeable renewable energy to the grid at different levels (transmission, distribution and grid-connected), the volatility on both sides (source side and load side) leading to bidirectional power flow in the power grid complicates the control mechanism. In order to ensure the real-time power balance, energy exchange, higher energy utilization efficiency and stability maintenance in the electric power system, this paper proposes an integrated application of blockchain technology on energy routers at transmission and distribution networks with increased renewable energy penetration. This paper focuses on the safe and stable operation of a highly penetrated renewable energy grid-connected power system and its operation. It also demonstrates a blockchain-based negotiation model with weakly centralized scenarios for “source-network-load” collaborative scheduling operations; secondly, the QoS (quality of service) index of energy flow control and energy router node doubly-fed stability control model were designed. Further, it also introduces the MOPSO (multi-objective particle swarm optimization) algorithm for power output optimization of multienergy power generation; Thirdly, based on the blockchain underlying architecture and load prediction value constraints, this paper puts forward the optimization mechanism and control flow of autonomous energy coordination of b2u (bottom-up) between router nodes of transmission and distribution network based on blockchain.


2014 ◽  
Vol 2014 ◽  
pp. 1-13
Author(s):  
Agustín Flores ◽  
Eduardo Quiles ◽  
Emilio García ◽  
Francisco Morant ◽  
Antonio Correcher

This work proposes a new method for fault diagnosis in electric power systems based on neural modules. With this method the diagnosis is performed by assigning a neural module for each type of component comprising the electric power system, whether it is a transmission line, bus or transformer. The neural modules for buses and transformers comprise two diagnostic levels which take into consideration the logic states of switches and relays, both internal and back-up, with the exception of the neural module for transmission lines which also has a third diagnostic level which takes into account the oscillograms of fault voltages and currents as well as the frequency spectrums of these oscillograms, in order to verify if the transmission line had in fact been subjected to a fault. One important advantage of the diagnostic system proposed is that its implementation does not require the use of a network configurator for the system; it does not depend on the size of the power network nor does it require retraining of the neural modules if the power network increases in size, making its application possible to only one component, a specific area, or the whole context of the power system.


2018 ◽  
Vol 55 (2) ◽  
pp. 3-10
Author(s):  
A. Obushevs ◽  
A. Mutule

Abstract The paper focuses on the application of synchrophasor measurements that present unprecedented benefits compared to SCADA systems in order to facilitate the successful transformation of the Nordic-Baltic-and-European electric power system to operate with large amounts of renewable energy sources and improve situational awareness of the power system. The article describes new functionalities of visualisation tools to estimate a grid inertia level in real time with monitoring results between Nordic and Baltic power systems.


2021 ◽  
Vol 286 ◽  
pp. 02009
Author(s):  
Ivaylo Nedelchev ◽  
Hristo Zhivomirov ◽  
Yoncho Kamenov

The renewable energy take part in the most of the electric power systems in the modern world. The part of this type of energy in the global electric power system, as well as in the local scale, increases with the setting the stricter requirements for decreasing the level of the carbon dioxide emissions. This is the result of the newest international conventions and decision for saving the nature. By these conditions, the electric power systems are forced to work with more different types of energy sources: wind power, photovoltaic, biomass plants etc. Switching of such miscellaneous power sources, leads to complicated transient processes, which are developed due to specific electrical parameters, especially harmonic components, of the synchronous generators, photovoltaic and wind power plants. This paper represents data from measurements of the transient processes into the physical model of the electric power system with predominant part of renewable energy and assesses the applicability of the model. For conducting this study, the multichannel DAQ measurement system is used.


Sign in / Sign up

Export Citation Format

Share Document