An EMTP simulation of PLC receiver based on OFDM

DC distribution system is one of technologies for reducing the loss of electric power transmittion because the most of loads are recently driven by DC source. For a farther improvement of the efficiency, an optimum control of loads is required. Power line communication (PLC) is suitable for its communication. A simulation of a PLC for a DC distribution system based on orthogonal frequency-division multiplexing (OFDM) modulation by Electromagnetic Transients Program (EMTP) with MODELS is reported in this paper. A binary phase shift keying (BPSK) and a discrete Fourier transform (DFT) which are major elements of the OFDM is described in the MODELS. A capacitive load and a noise current cause a communication error due to the phase shift in the DFT output within the OFDM receiver. A resonance between the capacitive load and the line inductance affects the phase shift in a high frequency region. A series blocking inductor is required to improve the communication stability against the capacitive load. Although the OFDM inherently has a high tolerance to noise, the communication is interfered by a truncation error of the DFT due to the noise. These phenomena are reproduced by the proposed method including the characteristics both of the electrical circuit and the communication system.