Fundamental System Frequency Detection and Flicker Analysis Mechanism for Intelligent Electronic Devices and Digital Protection Relays

• Main Authors: Shih-Che Lin, 林士哲
• Other Authors: Wen-Kung Chang
• Format: Others
• Language: en_US
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/14445518048256812265

碩士 === 國立中正大學 === 電機工程研究所 === 101 === With the widespread use of nonlinear loads in the power system, pollutions of power quality have become serious. Besides, the power unbalance between the generation and the load demand would make the fundamental frequency varying with time. These disturbances may introduce operational problems of power system equipment. When a fault occurs, the protection relay will be fast operated. Then, the protection relays will isolate the faulted zone to reduce the extent of damage to the equipment so that the power system remains stable and protects the safety of the system and staff. Protection relays need to rely on accurate measurement of basic parameters. Therefore, the protection relays will make the most appropriate decisions. These parameters include voltage, current, and fundamental frequency. Many controls and protections of the power system need to have accurate measurements of the fundamental frequency, which is one of the most important index in power quality and protection relays. For quick measuring fundamental frequency of system and study the influence of power quality on the performance of protection relays, this thesis proposes a mechanism which is applied for fundamental frequency measurement and flicker analysis in intelligent electronic devices (IED) or digital protection relays. In this thesis, the flickermeter combines with frequency tracking methods in which the flickermeter is based on IEC (International Electrotechnical Committee) standard 61000-4-15. Therefore, the mechanism not only evaluates the flicker severity in voltage signal but also detects fundamental frequency. Finally, this mechanism is written into DSP F2812 and an arbitrary waveform generator is used to produce actual signals as inputs to LabVIEW and DSP F2812 to verify the mechanism’s effectiveness and usefulness.