Communication Concept for Sensors at an Inverter-Fed Electric Motor Utilizing Power-Line Communication and Energy Harvesting

In this paper, a novel communication concept for sensors at an inverter-fed electric motor is proposed. The concept utilizes power-line communication and a motor cable in data transmission. The signal used in communication is inductively coupled to the motor cable. The supply power for sensing and communication at the electric motor is harvested from the motor-phase conductor with a current-transformer-based power supply. The proposed concept has numerous advantages, such as no galvanic connection to the motor power circuit, an opportunity to implement the concept afterwards without electrical installation, and reliable and battery-free operation. The operation of the concept is analyzed, simulated, and verified by laboratory measurements.