Oscillator disciplining system for satellite clock device of power system

Abstract

The invention discloses an oscillator disciplining system for a satellite clock device of a power system, which comprises a digital phase discriminator which takes 1PPS output by a satellite time transfer receiver as a reference to discriminate the phase of 1PPS output by a high-stability crystal oscillator at divided frequency, wherein the digital phase discriminator is connected with a proportional integral controller; the voltage output by the proportional integral controller is transmitted to a pressure controlled control end of the high-stability crystal oscillator; the pressure controlled control end performs the fine adjustment of output frequency; and the high-stability crystal oscillator is connected with a frequency divider. The oscillator disciplining system for the satellite clock device of the power system is reasonable in structure, can eliminate an accumulated phase error and has excellent tracking performance. Due to adopted proportional plus integral control, the 1PPSoutput by the high-stability crystal oscillator can track the 1PPS of a satellite step by step, and if the 1PPS of the satellite is stable and final phase error is zero. When the 1PPS of the high-stability crystal oscillator locks the 1PPS of a satellite, the frequency of the 1PPS is calibrated.

Description

Technical field: [0001] The invention relates to an oscillator taming system for a satellite clock in a power system. Background technique: [0002] The power system covers a wide range, and automation devices are very popular at present. The measurement of electric energy and power requires the clock accuracy to reach the microsecond level, and the traveling wave ranging and traveling wave protection require the clock accuracy to reach the microsecond level. All nodes in the power system, such as power plants and substations, require strict time synchronization. Among various time synchronization technologies, satellite timing is widely used due to its wide coverage, high precision and relatively low cost. However, the satellite is tens of thousands of kilometers away from the ground, and the signal transmission is susceptible to interference. In order to ensure the reliability of the clock. The method of combining the local oscillator and satellite timing must be used. U...

AI Technical Summary

Problems solved by technology

[0003] In the technology of combining satellite timing and local crystal oscillator, some literature proposes to establish a quadratic equation of the crystal oscillator based on the second signal of the satellite to correct the crystal oscillator in real time. This method requires a large number of tests on the crystal oscillator in advance. Due to the difference in production , the model does not have wide availability, such as considering the aging rate of the crystal oscillator itself, the model will be more complicated; some literature uses a single-chip microcomputer to read the phase difference, establish a digital phase-locked loop, adjust the constant temperature crystal oscillator according to the output of the phase-locked loop Tuning voltage, but the literature does not give a detailed design of the phase-locked loop; some literature proposes the method of using the phase difference to obtain the frequency difference, but does not propose a phase compensation scheme; some literature combines the satellite with a high-stable crystal oscillator with good short-term stability, Form a digital phase-locked loop, and use the locked frequency as a reference for a direct digital frequency synthesizer; the document fails to describe the design and implementation of a digital phase-locked loop in detail

Images