DistanceRelay - Real time embedded firmware of Distance Relay - for Aluminium Industries

Distance relay finds its application in electrical transmission systems. Basically to prevent the systems associated in generation , distrubution & the transmmision line from fault that might occur during power distribution . This distance relay will detect the fault as well as the fault location.The relay derives the impedance depending on the voltage, current signals & based on this value, finds the distance from the relay location to the fault point. Developed for Aluminum Industries,Thiruvananthapuram, Kerala, India.


  • System consists of signal conditioning circuits, sample & hold circuits, ADCs, microcontrollers & DSPs,CTs & PTs
    Very linear CTs & PTs to step down the current & voltage
  • Signal conditioning circuits consists of filters to chop out the unwanted signals, variable gain amplifiers to amplify the signal to a desired level
  • Sample & hold circuit can adjust the sampling rate depending on the frequency of the input signal & can hold the data for the ADC to read it
  • 13 bit ADCs, used for A/D conversion
  • 16 bitMicro-controllers are used as front-end wich does the data acquisition & gets relay settings from the pheripheral devices
  • DSPs 16 bit, 12 Mhz. which does all data processing, fault location calculations & gives the final trip if there is a fault
  • Calculations are done for every sample
  • Fourier algorithm implementation to get the fundamental value of the signal
  • Fault detection with minimum amout of time
  • Makes use of quadrilateral characteristics for fault location & detection
  • Power swing blocking is provided
  • User selectable time & other settings are provided