The invention provides a control instruction
time sequence synchronization method and device of a multi-node
industrial control system. The control instruction
time sequence synchronization method comprises the following steps: a control node calculates an initial time offset through a calibration frame, loops back a
test frame to measure link
transmission delay, and compensates a local
clock of an execution node to realize initial alignment; periodically
broadcasting a reference
clock, calculating an accumulated drift amount in real time by an execution node, and adjusting a local
clock frequency when the accumulated drift amount exceeds a threshold value; sending a control instruction based on a synchronization period starting moment,
synchronizing a trigger
signal to enable an execution node to sample data at the same time, and reading the data by a period ending boundary. According to the control instruction
time sequence synchronization method, the initial synchronization precision is + / -10ns, the accumulated drift distance is controlled within + / -10ns, the total time sequence deviation is smaller than 100ns,
system errors are effectively eliminated, the problem of
crystal oscillator deviation is solved, the method can be compatible with an industrial
bus, the hardware cost is reduced, and the multi-axis cooperative control precision and stability are greatly improved.