Time Synchronization Method and Apparatus, and Storage Medium

A network device, comprising:

• a memory configured to store computer-readable instructions;
• and
• a processor coupled to the memory, wherein the computer-readable instructions cause the processor to be configured to:
• generate data about voltage zero-crossing points based on a reference time, wherein the data comprise zero-crossing time points of the voltage zero-crossing points;
• and
• send first information to a tail end node when a first timing point arrives,
• wherein the first information comprises a timestamp of a first zero-crossing point,
• wherein the timestamp is a first zero-crossing time point that is in the zero-crossing time points and that has a smallest time interval with the first timing point, and
• wherein the timestamp enables the tail end node to determine a second zero-crossing time point of a second zero-crossing point.

A terminal device, comprising:

• a memory configured to store computer-readable instructions;
• and
• a processor coupled to the memory, wherein the computer-readable instructions cause the processor to be configured to:
• receive first information from a first node when a first timing point arrives, wherein the first information comprises a first timestamp of a first zero-crossing point, wherein the first timestamp is a first zero-crossing time point that is in zero-crossing time points of voltage zero-crossing points and that has a smallest time interval with the first timing point:
• and
• determine a second timestamp of a second zero-crossing point based on the first timestamp.

A power-line communication (PLC) communications system comprising:

• a head end node configured to:
• generate data about voltage zero-crossing points based on a reference time, wherein the data comprises comprise zero-crossing time points of the voltage zero-crossing points;
• and
• send first information when a first timing point arrives, wherein the first information comprises a first timestamp of a first zero-crossing point, and wherein the first timestamp is a first zero-crossing time point that is in the zero-crossing time points and that has a smallest time interval with the first timing point;
• and
• a tail end node coupled to the head end node and configured to:
• receive the first information from the head end node;
• and
• determine a second zero-crossing time point of a second zero-crossing point based on the first timestamp.