Device and method for processing input data of protective relay

A device for processing input data of a protective relay, the device comprising:

• a detecting unit configured to detect a voltage and current;
• an analog-digital converting unit configured to convert an analog signal input via the detecting unit into digital data, the digital data comprising event data, fault data, wave data, and demand data;
• a memory configured to store data;
• and
• a digital signal processing unit comprising a measurement accumulation buffer and an update accumulation buffer, the digital signal processing unit configured to:
• perform an RDFT (Recursive Discrete Fourier Transform) operation on the digital data input via the analog-digital converting unit;
• buffer the RDFT-operated data in the measurement accumulation buffer and the update accumulation buffer;
• control the memory to store the buffered data item-by-item;
• and
• in every period, input a value of the update accumulation buffer to the measurement accumulation buffer and initialize the value of the update accumulation buffer to ‘0’.