Title :
Real wavelet-domain modified phasor: Principle and applications in power systems
Author_Institution :
Nat. Eng. Res. Center for T&D, China Electr. Power Res. Inst. (CEPRI), Beijing
Abstract :
Wavelet transform is a new competitive tool to deal with power quality disturbances. Real discrete wavelet transform (RDWT) is simple, fast and non-redundant, but is regarded to be lack of phase information (PI). This paper presents three RDWT-based PI extraction methods and then develops a modified phasor Zw(n) in real wavelet domain to analyze single-frequency or narrow-band signal. Amplitude, frequency and phase of the signal simply relate to the phasor. Zw(n) can be used to separate, identify and quantify frequency disturbance, phase disturbance and amplitude disturbance at one time quickly. Demonstration examples are given. The modified phasor may have practical application in custom power and protective relays.
Keywords :
fault diagnosis; power supply quality; power system protection; relay protection; wavelet transforms; PI extraction methods; amplitude disturbance; frequency disturbance; narrowband signal; phase disturbance; phase information; power quality disturbances; protective relays; real discrete wavelet transform; single-frequency analysis; Data mining; Discrete wavelet transforms; Frequency; Narrowband; Power quality; Power systems; Protection; Signal analysis; Wavelet analysis; Wavelet domain; Amplitude disturbance; Frequency disturbance; Modified phasor; Phase disturbance; Phase information; Power quality; Real discrete wavelet transform;
Conference_Titel :
Power and Energy Society General Meeting - Conversion and Delivery of Electrical Energy in the 21st Century, 2008 IEEE
Conference_Location :
Pittsburgh, PA
Print_ISBN :
978-1-4244-1905-0
Electronic_ISBN :
1932-5517
DOI :
10.1109/PES.2008.4596005