BeiDou-1 timing technology and its application in power systems

Brief: Based on the current timing technology and market situation, this article introduces the working principle of Beidou timing terminal, the application methods and characteristics of Beidou timing terminal, and the application examples of Beidou timing terminal in power system .

1. Introduction

For a modern country entering the information society, the navigation positioning and timing system is the most important and one of the most critical national infrastructures. Precision time is a basic physical parameter in scientific research, scientific experiments and engineering technology. It provides an indispensable time base coordinate for the measurement and quantitative research of all dynamic systems and time processes. Precision timing has extensive and important applications in industrial fields such as communications, electricity, control and defense. Modern weapons experiments and wars require its guarantee, and the establishment of intelligent transportation systems and the realization of the digital earth require its support. The construction of modern communication networks and power grids has also increasingly increased its dependence on precision time and frequency. From the overall consideration of the large system engineering of building a modern country, the navigation positioning and timing system should be said to be the foundation of the foundation. Its support for the entire society is almost all-round. Satellite-based navigation and timing are an inevitable trend for development.

The current satellite timing synchronization technologies mainly include the United States' global satellite navigation system GPS , Russia's global navigation satellite system GLONASS, China's BeiDou-1 navigation and positioning system and the European Union's Galileo global navigation and positioning system Galileo. Based on the security considerations of timing, domestic power companies currently rely mainly on the global satellite positioning system GPS time synchronization technology, but GPS is restricted by the United States and is free to use, so it has low reliability and poor autonomy. In order to meet the time requirements and security needs of power production and management businesses, it is necessary to study and promote the application of BeiDou-1 timing synchronization technology. In this article, only BeiDou timing technology and its application in power systems are introduced.

The time synchronization referred to in this article refers to the synchronization of the time and time intervals of the clocks of each node in the network and the clocks of each application interface connected through the network with the Coordinated Universal Time (UTC).

2. Beidou timing principle and characteristics

1. BeiDou-1 timing principle

Timing means that the receiver obtains the clock difference between the local time and the Beidou standard time in some way, and then adjusts the local clock to control the time difference within a certain accuracy range.

Satellite navigation systems usually consist of three parts: navigation and timing satellites, ground detection, correction and maintenance systems, and user receivers. For the BeiDou-1 local satellite system, the ground detection center will help users complete positioning and timing synchronization.

In the Beidou navigation system, timing users continuously verify their clock errors based on the satellite's broadcast or positioning information to obtain very high clock accuracy. Based on the timing characteristics of the broadcast or navigation message, a high-precision synchronous second pulse 1pps signal can be obtained through a counter, which is used for synchronous operations of multi-channel data acquisition and control in the same or different locations.

"Beidou-1" provides two timing modes for user terminals: one-way timing and two-way timing. The accuracy of one-way timing is 100ns, and the accuracy of two-way timing is 20ns. In the one-way timing mode, the user terminal does not need to exchange information with the ground central station, but only needs to receive Beidou broadcast telegram signals, and independently obtain the clock difference between the local time and the Beidou standard time to achieve time synchronization; in the two-way timing mode, the user terminal exchanges information with the central station, sends a timing application signal to the central station, and the central station calculates the time difference of the user terminal, and then forwards it to the user through the outbound signal via the satellite. The user adjusts the local clock to align with the standard time signal according to this time.