Low Voltage Inbound Powerline Communication Based on Talkative Power Conversion

In the informational low voltage (LV) power grid, inbound communication possesses significant importance. Utilizing LV inbound powerline communication (PLC) based on talkative power conversion (TPC) can effectively facilitate the establishment of LV smart grids. This article conducts a comprehensive study and design of TPC-based LV inbound PLC, and introduces a digital transmission method which is suitable to the application with ultra-low signal noise rates (SNRs). By analyzing the mechanism of nonlinear load circuits, the powerline channel characteristics at low frequencies are elaborated. Leveraging these insights, we propose a digital bandpass transmission method to counteract substantial interferences within the LV channel. This method incorporates binary phase shifting keying (BPSK) modulation, along with an innovative signal accumulation process. Considering applications in compact grid equipment, we select a boost power factor correction (PFC) circuit as the hardware transponder. This transponder employs the TPC technique to encode the carrier within current ripples. In scenarios where the SNR in the channel falls below -19.5 dB, the LV inbound PLC method achieves a bit error rate (BER) of 10% at 2.4 kHz, with the transmission rate of 50 bits/s. Finally, experiments are carried out on the TPC transponder hardware, which shows the potential applicability in real-world LV power grid settings.