IEEJ Transactions on Power and Energy
Online ISSN : 1348-8147
Print ISSN : 0385-4213
ISSN-L : 0385-4213
High-Precision Techniques of Analog Input Unit for Advanced Digital Protection Relay
Takayuki MatsudaKen YanagibashiTakafumi MaedaTomio ChibaMitsuyasu KidoTadao Kawai
Author information

1994 Volume 114 Issue 7-8 Pages 777-784


Power system control and protection equipment has required higher sensitibity and operational reliability than conventional one.
Studies of digital signal processing suitable for electric power systems fullfil this objection using fast sampling and digital filtering by a 32-bit DSP (Digital Signal Processor).
The fast sampling rate of 4.8kHz is carefully selected a point of view of A-D conversion time, operational ability of DSP for digital filter, the size of analog filter and the power spectrums of the A-D conversion output errors. The new analog input unit using a 16-bit A-D converter equipped with a recursive-type digital filter achieved high resolution of 14-bit conversion.
This paper describes the design concept and high-precision techniques of analog input unit for advanced digital protection relays. In addition, measured total A-D conversion errors filtered by the digital filters are described along with new analog filter characteristics.

Information related to the author
© The Institute of Electrical Engineers of Japan
Previous article Next article