1. PLC-Based Anti-Islanding and Fault Locating System Concept A
PLC-Based Anti-Islanding and Fault Locating System Concept A. Poluektov, A. Pinomaa, J. Ahola, and A. Kosonen Electrical Engineering, LUT School of Energy Systems Lappeenranta University of Technology (LUT) Lappeenranta, Finland

2. Problem statement Present solutions
Research reason: modern grids with DGs pose new safety-related issues
Loss of Mains (LoM) and islanding
Types of LoM detection methods
Passive
Active
Communication-based
motivation

3. Initial idea Physical constraints Idea: PLC-based LoM detection
Signal propagation
Grid topology, cable materials, transformers
Noise scenario
Data transmission rate
Signaling power

4. Initial idea Physical constraints PLC-based LoM detection
Signal propagation
Noise scenario
Data transmission rate
Signaling power
System topology
Frequency band
Available power
Signal generation
Signal loss detection concept

5. Concept topology CENELEC band 3‒148.5 kHz Signaling PSK DSSS
OFDM (in the design process)
LoM detection
Signal level analysis
Signal demodulation

6. Laboratory tests Software-defined radios
MV/LV 20/0.4 kV distribution transformer
PSK and DSSS modulations
LoM detection
SNR
BER
USRP N200 by Ettus Research

7. Laboratory tests Results
Stable PSK and DSSS(BPSK) data transmission software instruments are designed
Over transformer signaling is performed and signal attenuation is analyzed
LoM detection is tested
SNR: 20–30 ms detection
BER (Real-time detection is not possible yet. High software latency, due to data processing)
SNR analysis mechanism is freely adjustable
 NDZ and detection speed can be modified

8. Conclusions
Concept topology: PLC from main substation at the MV side to DGs at the LV side
Frequency band: CENELEC band
Coupling: capacitive or inductive couplers, intermediate PLC units are coupled at transformers at MV and LV
LoM detection principle: SNR and BER analysis
Signal modulation: PSK, DSSS
Next steps:
OFDM
CDMA and grid monitoring functionality