Selection of optimal frequency band for motor cable communication

In previous publications it has been demonstrated that the power line communication (PLC) is a feasible method for data transmission between a LV (Low Voltage) motor and a frequency converter. In this paper, attenuation and noise power spectrum of the motor cable communication channel are analyzed. The analysis is based on a laboratory test setup, laboratory measurements, simulation models, and known PSD (Power Spectral Density) limits for industry standard PLC (Power Line Communication) equipment. The modeling principles, used in simulation models, are presented. According to the analysis, in the researched cases, the frequency band 20-30 MHz is feasible for the motor cable communication. In addition, data transmission in the test setup is demonstrated with a low-cost 27 MHz radio transceiver operating at a license free RF band, and using the transmission power of approximately 1 mW.