DC–AC Talkative Power Conversion Based on Variable Zero-Vector Position Modulation
Yang Leng, Rongwu Zhu, Peter Adam Hoeher, Marco Liserre
Abstract
Talkative power conversion (TPC), which embeds information in the switching ripple to achieve simultaneous power and data transmission without installing any or few additional hardware at the transmitter side, can reduce the additional communication infrastructure needed in cyber-physical systems like smart grids and renewable power plants. While in dc–dc converters TPC has been the subject of numerous investigations, dc–ac converters have received less attention. Recently, zero vectors of three-phase dc–ac converters were used to embed data, and variable zero vector width modulation TPC has been investigated. In this study, a novel zero vector-based modulation, called variable zero-vector position modulation, is proposed for three-phase dc–ac TPC with improved communication performance. This type of dc–ac converter can send data through the power line to the demodulator with good power quality. The viability of using sliding fast fourier transform (FFT)-based demodulation for target side-band harmonics is supported by a mathematical study of the harmonic distribution. The results of MATLAB/Simulink-based simulations and scaled-down prototype-based experimental results verify the correctness of the theoretical analysis. Besides, the bit error rate is evaluated for different line lengths and zero vector positions.