Relative phase detection in power line communications networks

摘要

Systems and methods for relative phase detection and zero crossing detection for power line communications (PLC) are described. In some embodiments, both transmit and receive PLC devices detect a zero crossing on an AC mains phase. The devices start a phase detection counter (PDC) by generating a zero crossing pulse within 5% of the actual zero crossing time. When a frame is transmitted, the transmitting device includes a PDC value in the frame control header (FCH). The PDC value corresponds to the start time of the FCH. When the frame is received at the receive PLC device, the receive PLC device measures a local PDC value between the zero crossing and the start of the FCH. The receive device compares the local PDC value to the PDC value in the FCH of the received frame and determines if the devices are on the same phase.

主权项

1. A method comprising:
performing, by a power line communication (PLC) device,
starting a phase detection counter (PDC) upon detecting a zero crossing on a phase of an AC mains;generating a zero crossing pulse upon detection of the zero crossing, a center of the zero crossing pulse occurring within an error limit of an actual zero crossing on the AC mains, the zero crossing pulse used to start the PDC;determining a PDC value at a frame transmission time, the PDC value representing a duration between the zero crossing and an initial transmission of a designated segment within a frame; andcreating the frame for transmission to a remote PLC device, the frame comprising the PDC value.