4results about How to "Improve time synchronization accuracy" patented technology

The application provides a time synchronization system and method based on a TDMA system wireless network virtual-real joint simulation, which comprises a physical network and a virtual network simulation system, time synchronization between multiple physical nodes of the physical network is completed through radio frequency signals, and wireless communication of the TDMA system is adopted; one of the physical nodes is a gateway node, the gateway node is provided with a first interface and a second interface, the first interface is used for generating a time slot pulse signal, and the second interface is used for generating a time slot numerical signal; the virtual network simulation system communicates with the physical network, and the virtual physical network system is provided with a third interface for receiving the time slot pulse signal and a fourth interface for receiving the time slot numerical signal; wherein the time slot pulse signal carries synchronization interrupt information, the time slot numerical signal carries time slot time information, and the virtual network simulation system realizes time synchronization with the physical network through the time slot pulse signal and the time slot numerical signal. The application has high time synchronization precision and low resource consumption.

This invention discloses an algorithm for improving time synchronization accuracy in a master-slave network topology. The algorithm comprises the following steps: S1, establishing a master-slave network topology; S2, exchanging messages to obtain four timestamps and calculating the master-slave clock offset and average link delay, sending an Optimize_Req message to the master clock; S3, selecting the optimal master-slave clock offset from multiple offsets and calculating the asymmetric link delay ratio for each synchronization; S4, if the current link delay is approximately symmetrical, the master-slave clock offset is used to update the slave clock; S5, if the current link delay is asymmetric, the clock offset estimate is obtained using the maximum likelihood estimation algorithm, and an Optimize_Resp message is sent to the slave clock to update it. This invention improves the PTP time synchronization protocol by using the above algorithm, adding two message transmissions. The master clock receives the synchronization results from multiple slave clocks, further performs filtering and optimization, and then sends the updated results to the slave clocks, allowing the slave clocks to adjust themselves.

This invention discloses a method and apparatus for transformer fault detection based on sound signals. The method includes: acquiring a target sound signal and a leakage flux signal of the transformer; determining the phase deviation between the target sound signal and the leakage flux signal based on the fundamental frequency of the target sound signal and the fundamental frequency of the leakage flux signal; determining the frequency coupling relationship between the leakage flux signal and the target sound signal; extracting the time-frequency features of the target sound signal; and determining the transformer fault detection result based on the phase deviation, frequency coupling relationship, and time-frequency features. This invention solves the technical problem of inaccurate fault detection in related technologies when using sound signals to detect transformer faults.