A New FFT-Based Digital Frequency Relay for Load Shedding

Girgis,; Ham,

doi:10.1109/mper.1982.5520276

Cited by 6 publications

(8 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The idea of the load shedding based on the rate of change of frequency can be traced back to as early as in 1960s [29][30]. Issues of hardware implementations in the form of relays were discussed and resolved in the 70s and 80s.…”

Section: Load Shedding Schemementioning

confidence: 99%

“…Issues of hardware implementations in the form of relays were discussed and resolved in the 70s and 80s. In [30], the leakage occurring in the fast Fourier transform (FFT) is advantageously used to detect the fluctuations in the fundamental frequency of a power system so that it can optimally estimate the mean frequency and its average rate of decline and determine the appropriate amounts of load to be shed. The idea was then adopted in an isolated power system [31][32], In the United Kingdom, the principal of the rate of change of frequency used for load shedding is referred to as ROCOF.…”

Section: Load Shedding Schemementioning

confidence: 99%

See 1 more Smart Citation

Self-healing in power systems: an approach using islanding and rate of frequency decline-based load shedding

You

Vittal

Yang

2003

IEEE Trans. Power Syst.

216

View full text Add to dashboard Cite

The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleed-through, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion.

show abstract

Section: Load Shedding Schemementioning

confidence: 99%

Section: Load Shedding Schemementioning

confidence: 99%

Self-healing in power systems: an approach using islanding and rate of frequency decline-based load shedding

You

Vittal

Yang

2003

IEEE Trans. Power Syst.

216

View full text Add to dashboard Cite

show abstract

“…Substituting Eqns. (5) and (6) (9) Where P e (pu) and P m (pu) are the per unit electrical power and mechanical power.…”

Section: Introductionmentioning

confidence: 99%

“…(10), it can be observed that the mismatches between demand and supply results in frequency change. Thus in order to measure the real time power frequency, different techniques have been developed namely; Newton method; level crossing technique; modified zero-crossing technique least-square error technique; Discrete Fourier Transform (DFT); leakage effect technique; Kalman filter technique; and phasor-based technique and Prony Method [6][7]. However in practical system, most of the relays worked on the principle of zero crossing detection [8][9].…”

Section: Introductionmentioning

confidence: 99%

Modeling and simulation of digital frequency relay for generator protection

Aman

Jasmon

Mokhlis

et al. 2012

2012 IEEE International Conference on Power and Energy (PECon)

View full text Add to dashboard Cite

Modeling tools are useful for educational and industrial use. Such tools help the new engineers to simulate the power system under normal and faulted conditions. This paper presents the design and various data conversion steps of a digital frequency relay. The designed relay will cover both over and under frequency conditions. The digital relay has superiority over electromechanical relay in terms of accuracy and speed. The large frequency variations could lead to complete power system blackout. History has seen several blackouts due to frequency instability, either due to supply-demand unbalance or N-1 contingency. After distributed generation and the possible islanding issues, frequency relay has again gain the attention of the researchers and industrialists. The performance of proposed digital frequency relay will be observed under different system dynamics on MATLAB/ SIMULINK®.

show abstract

“…Sachdev and Giray [4] and Nguyen and Srinivasan [5] measure the duration of an integer number of cycles of the voltage waveform and calculate the frequency from those measurements. Girgis [6] calcu lates the leakage of the fast Fourier transform (FFT) and estimates frequency deviation from it. A zero-crossing detector is used to initiate the procedure for obtaining each frequency estimate.…”

Section: Introductionmentioning

confidence: 99%

A study of estimation techniques for frequency-relaying applications

El-Hawary

Mostafa

El-Arabaty

et al. 1996

Can. J. Electr. Comput. Eng.

View full text Add to dashboard Cite

This paper presents an evaluation and performance comparison of two estimating algorithms used for frequency-relaying applications. The first algorithm is based on least squares (LS) error estimation, while the second is based on the least absolute value (LAV) approximations. Two models for frequency estimation, namely the constant-frequency model (CFM) and the variable-frequency model (VFM), are used. CFM is used to measure the steady-state frequency deviation, while VFM is used to measure the transient frequency and its rate of change. For the constant-frequency model, which is suitable for use in microprocessor-based relays, the algorithms are tested using two data sets. The first involves a pure sine waveform, and the second is a wave generated from the electromagnetic transients program (EMTP) simulating a study system. The EMTP is used to generate the corresponding voltage samples at a relay location. Fault conditions applied on the study system to generate distorted waves with and without frequency deviations are considered. For the variable-frequency model, the algorithms are tested using a data set generated from a pure sine waveform. The effects of sampling rate, sample window size and bad data on the performance of each algorithm are studied. A comparison of the results is offered to evaluate the two techniques. Cet article propose une Evaluation et une comparaison des performances de deux algorithmes d'estimation employes pour des applications a relais de frequence. Le premier algorithme est bas6 sur 1'estimation d'erreur des moindres carres, alors que le second algorithme emploie les approximations de la moindre valeur absolue. Deux modeles pour 1'estimation de frequence, soit le modele a frequence constante (MFC) et le modele a frequence variable (MFV), sont employes. Le MFC sert pour mesurer la deviation de la frequence en regime permanent, alors que le MFV permet de mesurer les frequencestransitoires ainsi que leur taux de variation. Dans le cas du modele a frequence constante, qui est adaptable a des systemes de relais a micro-processeurs, les algorithmes sont tester avec deux ensembles de donnees. Le premier ensemble est en fait une onde sinusoidale pure et le second est un signal produit par le programme EMTP qui simule le systeme 6tudie\ Le programme EMTP produit les Schantillons de tension a la localisation meme d'un relais. L'occurrence de pannes dans le systeme, pannes qui peuvent engendrer des ondes avec et sans deviation de frequence, est considered. Pour le modele a frequence variable, les algorithmes sont tested en employant des ensembles de donnees purement sinusoidaux. Les effets du taux d'lchantillonnage, de la taille de la fenetre et de donnles erron6es sur la performance de chaque algorithme sont 6tudi6s. Une comparaison des rSsultats est presented pour ^valuer les deux techniques.

show abstract

A New FFT-Based Digital Frequency Relay for Load Shedding

Cited by 6 publications

References 0 publications

Self-healing in power systems: an approach using islanding and rate of frequency decline-based load shedding

Self-healing in power systems: an approach using islanding and rate of frequency decline-based load shedding

Modeling and simulation of digital frequency relay for generator protection

A study of estimation techniques for frequency-relaying applications

Contact Info

Product

Resources

About