Automatic timing system and method based on carry delay chain

Abstract

The invention discloses an automatic timing system and method based on a carry delay chain. The system comprises a carry delay chain, a signal comparison module and a time offset calculation module, the signal comparison module is used for acquiring a first signal generated by a crystal oscillator in the individual soldier operation and maintenance device and acquiring a second signal output by the carry delay chain; the second signal is a signal obtained by inputting the first signal into the carry delay chain; the signal comparison module is used for determining a phase difference signal of the first signal and the second signal; and the time deviation calculation module is used for calculating the timing deviation of the crystal oscillator according to the phase difference signal of the first signal and the second signal, and adjusting the time counting logic of the individual soldier operation and maintenance device according to the timing deviation. According to the technical scheme, the problems of large time correction difficulty, low accuracy, high cost and the like of the individual operation and maintenance device are solved, the frequency change of the crystal oscillator is calibrated through the inherent time delay of the carry delay chain, automatic time correction of the individual operation and maintenance device is realized, the time correction cost is reduced, and the time correction precision is improved.

Description

Technical Field

[0001] The present invention relates to the field of power electronics technology, and in particular to an automatic timing system and method based on a carry delay chain. Background Art

[0002] The individual operation and maintenance device is an important device in the main distribution network relay protection test. The individual operation and maintenance device usually needs to have a high time accuracy to ensure the accuracy of the test results. Therefore, the individual operation and maintenance device is usually equipped with IRIG-B, GNSS and other interfaces for time synchronization. In order to further enhance the applicability of the individual operation and maintenance device in different test scenarios, the individual operation and maintenance device also needs to meet the requirements of self-timekeeping, that is, in the absence of an external clock source, to maintain time accuracy within a certain time range.

[0003] In order to meet the requirements of self-keeping, the existing technology usually replaces the conventional crystal oscillator in the individual operation and maintenance device with a constant temperature crystal oscillator or a temperature compensated crystal oscillator, so that the crystal oscillator maintains a small frequency deviation within a certain temperature range, and ultimately the time of the device maintains a high accuracy within a certain period of time.

[0004] However, constant temperature crystal oscillators usually face problems such as high power consumption, large size and high cost. Although temperature compensated crystal oscillators have temperature compensation circuits, they are still very sensitive to changes in ambient temperature and are difficult to calibrate. This paper uses the inherent delay of the FPGA carry delay chain to calibrate the crystal oscillator frequency change, and ultimately achieves high-precision time calibration, which has the characteristics of low cost, simple implementation and high precision. Summary of the invention

[0005] The present invention provides an automatic time calibration system and method based on a carry delay chain to solve the problems of difficulty, low accuracy and high cost in the time calibration of a single-soldier operation and maintenance device. The frequency change of the crystal oscillator is calibrated by the inherent time delay of the carry delay chain to achieve automatic time calibration of the single-soldier operation and maintenance device, which is beneficial to reducing the time calibration cost and improving the time calibration accuracy.

[0006] According to one aspect of the present invention, there is provided an automatic timing system based on a carry delay chain, the automatic timing system comprising a carry delay chain, a signal comparison module and a time offset calculation module;

[0007] The signal comparison module is used to obtain a first signal generated by a crystal oscillator in the individual operation and maintenance device, and to obtain a second signal output by a carry delay chain; wherein the second signal is a signal obtained by inputting the first signal into the carry delay chain;

[0008] The signal comparison module is used to determine a phase difference signal between the first signal and the second signal;

[0009] The time deviation calculation module is used to calculate the timing deviation of the crystal oscillator according to the phase difference signal between the first signal and the second signal, and adjust the time counting logic of the individual operation and maintenance device according to the timing deviation.

[0010] According to another aspect of the present invention, there is provided an automatic timing method based on a carry delay chain, the method being performed by an automatic timing system, the automatic timing system comprising a carry delay chain, a signal comparison module and a time offset calculation module; the method comprising:

[0011] Acquire a first signal generated by a crystal oscillator in the individual operation and maintenance device through a signal comparison module, and acquire a second signal output by a carry delay chain; wherein the second signal is a signal obtained by inputting the first signal into the carry delay chain;

[0012] Determine a phase difference signal between the first signal and the second signal by a signal comparison module;

[0013] The timing deviation of the crystal oscillator is calculated according to the phase difference signal between the first signal and the second signal through the time deviation calculation module, and the time counting logic of the individual operation and maintenance device is adjusted according to the timing deviation.

[0014] The technical solution of the embodiment of the present invention is to obtain the first signal generated by the crystal oscillator in the individual operation and maintenance device through a signal comparison module, and obtain the second signal output by the carry delay chain; the second signal is the signal obtained by inputting the first signal into the carry delay chain; the phase difference signal between the first signal and the second signal is determined through the signal comparison module; the timing deviation of the crystal oscillator is calculated according to the phase difference signal between the first signal and the second signal through the time deviation calculation module, and the time counting logic of the individual operation and maintenance device is adjusted according to the timing deviation. This solution solves the problems of difficulty in time calibration, low accuracy and high cost of the individual operation and maintenance device, and realizes automatic time calibration of the individual operation and maintenance device by calibrating the frequency change of the crystal oscillator through the inherent time delay of the carry delay chain, which is conducive to reducing the time calibration cost and improving the time calibration accuracy.

[0015] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1A is a structural schematic diagram of an automatic timing system based on a carry delay chain provided according to Embodiment 1 of the present invention;

[0018] Figure 1B is a circuit connection diagram of an automatic time synchronization system provided according to Embodiment 1 of the present invention;

[0019] Figure 2 The flowchart of an automatic timing method based on a carry delay chain is provided according to the second embodiment of the present invention. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0021] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, device, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices. The acquisition, storage, use, processing, etc. of data in the technical solution of this application comply with the relevant provisions of national laws and regulations.

[0022] Embodiment 1

[0023] Figure 1A The present invention provides a structural diagram of an automatic time synchronization system based on a carry delay chain. This embodiment is an automatic time synchronization system based on a carry delay chain. The system can be applied to substation relay protection scenarios, especially clock synchronization. Figure 1A As shown, the automatic timing system based on the carry delay chain includes a carry delay chain 110, a signal comparison module 120 and a time offset calculation module 130;

[0024] The signal comparison module 120 is used to obtain a first signal generated by a crystal oscillator in the individual operation and maintenance device, and obtain a second signal output by a carry delay chain; wherein the second signal is a signal obtained by inputting the first signal into the carry delay chain 110;

[0025] The signal comparison module 120 is used to determine a phase difference signal between the first signal and the second signal;

[0026] The time deviation calculation module 130 is used to calculate the timing deviation of the crystal oscillator according to the phase difference signal between the first signal and the second signal, and adjust the time counting logic of the individual operation and maintenance device according to the timing deviation.

[0027] In this solution, the automatic timing system is composed of a carry delay chain 110, a signal comparison module 120 and a time deviation calculation module 130. The crystal oscillator in the individual operation and maintenance device is connected to the carry delay chain 110, the carry delay chain 110 is connected to the signal comparison module 120, and the signal comparison module 120 is connected to the time deviation calculation module 130. Among them, the carry delay chain 110 refers to a transmission delay line formed by cascading multiple carry-lookahead logic structures (Carry-Lookahead Adders). The signal delay generated by the carry delay chain 110 is fixed, so it can be used to correct the crystal oscillator delay.

[0028] The carry delay chain 110 can obtain the square wave signal generated by the crystal oscillator in the individual operation and maintenance device, that is, the first signal, and delay the first signal to obtain the second signal. The signal comparison module 120 can obtain the first signal generated by the crystal oscillator in the individual operation and maintenance device, and at the same time obtain the second signal output by the carry delay chain, compare the phases of the first signal and the second signal, and output the phase difference signal between the first signal and the second signal. Specifically, the signal comparison module 120 can be a phase detector. If the rising edge of the first signal leads the rising edge of the second signal, the signal comparison module 120 outputs a positive polarity voltage; if the rising edge of the first signal lags behind the rising edge of the second signal, the signal comparison module 120 outputs a negative polarity voltage. Among them, the amplitude of the output voltage can be proportional to the phase difference between the first signal and the second signal.

[0029] The time deviation calculation module 130 can calculate the timing deviation of the crystal oscillator according to the phase difference signal between the first signal and the second signal, and adjust the time counting logic of the individual operation and maintenance device according to the timing deviation. Specifically, the time deviation calculation module 130 can calculate the period or frequency of the first signal output by the crystal oscillator according to the phase difference signal between the first signal and the second signal, and compare the period of the first signal with the period of the crystal oscillator, or compare the frequency of the first signal with the frequency of the crystal oscillator to obtain the timing deviation of the crystal oscillator. According to the timing deviation of the crystal oscillator, the automatic time correction system can adjust the time counting logic of the individual operation and maintenance device. It can be understood that the time counting logic of the individual operation and maintenance device can be used to represent the mapping relationship between unit time and the number of clock cycles.

[0030] In this solution, optionally, the automatic time calibration system further includes an input selection module;

[0031] The input selection module is used to determine the input signal of the signal comparison module according to the working mode of the automatic timing system; wherein the working mode includes a calibration mode and an application mode.

[0032] In order to ensure the reliability of the automatic time calibration system, the automatic time calibration system can perform an automatic calibration operation before application. The automatic time calibration system can include two working modes, namely, a calibration mode and an application mode. It is easy to understand that in the calibration mode and the application mode, the input signal of the signal comparison module 120 is different.

[0033] Based on the above solution, the automatic timing system further includes a pulse generation module;

[0034] The pulse generating module is used to generate a reference pulse signal;

[0035] The input selection module is specifically used for:

[0036] If the working mode of the automatic timing system is the application mode, it is determined that the input signal of the signal comparison module 120 is the first signal generated by the crystal oscillator in the individual operation and maintenance device and the second signal output by the carry delay chain;

[0037] If the working mode of the automatic timing system is the calibration mode, the input signal of the signal comparison module 120 is determined to be the reference pulse signal generated by the pulse generation module and the third signal output by the carry delay chain 110; wherein the third signal is the signal obtained by inputting the reference pulse signal into the carry delay chain 110.

[0038] In the calibration mode, the automatic timing system can use the pulse signal of the preset period generated by the pulse generation module as a reference pulse signal, input it into the carry delay chain 110, and calibrate the carry delay chain according to the third signal and the reference pulse signal output by the carry delay chain 110. Therefore, the input signal of the signal comparison module 120 is the reference pulse signal generated by the pulse generation module and the third signal output by the carry delay chain 110.

[0039] In application mode, the automatic timing system can use the first signal generated by the crystal oscillator in the individual operation and maintenance device and the second signal output by the carry delay chain 110 as input signals of the signal comparison module 120 to calibrate the frequency of the crystal oscillator according to the inherent delay of the carry delay chain 110.

[0040] In a feasible solution, the signal comparison module 120 is further used to determine a phase difference signal between the reference pulse signal and the third signal;

[0041] The time offset calculation module 130 is used to determine a phase-time mapping relationship according to a phase difference signal between the reference pulse signal and the third signal.

[0042] The time deviation calculation module 130 can determine the mapping relationship between the phase and time based on the period of the reference pulse signal and the phase difference signal between the reference pulse signal and the third signal. The phase-time mapping relationship can be characterized by analog signals such as voltage and current output by the signal comparison module 120. For example, a voltage amplitude of 1 mV indicates that there is a phase difference of 0.036 degrees between the two input signals of the signal comparison module 120, and a voltage amplitude of 1 mV indicates that there is a time difference of 0.0005 ns between the rising edges of the two input signals, that is, a phase difference of 0.036 degrees corresponds to a time difference of 0.0005 ns.

[0043] On the basis of the above solution, the time deviation calculation module 130 is used to calculate the timing deviation of the crystal oscillator according to the phase difference signal between the first signal and the second signal based on the phase-time mapping relationship.

[0044] The time deviation calculation module 130 can obtain the timing deviation of the crystal oscillator based on the phase-time mapping relationship according to the phase difference signal between the first signal and the second signal, and then adjust the time counting logic of the individual operation and maintenance device according to the timing deviation. Specifically, the time deviation calculation module 130 can calculate the period or frequency of the first signal output by the crystal oscillator according to the phase-time mapping relationship according to the phase difference signal between the first signal and the second signal, and compare the period of the first signal with the period of the crystal oscillator, or compare the frequency of the first signal with the frequency of the crystal oscillator, to obtain the timing deviation of the crystal oscillator. According to the timing deviation of the crystal oscillator, the automatic time calibration system can adjust the time counting logic of the individual operation and maintenance device.

[0045] Figure 1B is a circuit connection diagram of an automatic time synchronization system provided according to Embodiment 1 of the present invention. In a specific example, the automatic time synchronization system is constructed based on a Field Programmable Gate Array (FPGA). Figure 1B As shown, the signal comparison module 120 can be a phase detector, the pulse generation module can be a pulse generator, and the signal comparison module 120 can realize the switching of the input signal in the calibration mode and the application mode through the selector (MUX). The selection pin (selection PIN) of the FPGA is connected to the selector to control the gating of the input signal of the selector. For example, when the selection PIN outputs a high level, the selector selects the reference pulse signal output by the pulse generator; when the selection PIN outputs a low level, the selector selects the first signal output by the crystal oscillator. The input pin (input PIN) of the FPGA is connected to the output end of the selector. The output pin (output PIN) of the FPGA is connected to one input end of the phase detector, and the output end of the selector is connected to the other input end of the phase detector. The analog-to-digital conversion chip (ADC chip) is used to convert the analog signal output by the phase detector into a digital signal. The ADC acquisition module in the FPGA can obtain the digital signal output by the analog-to-digital conversion chip (ADC chip), restore the digital signal to an analog signal, and input the analog signal to the carry delay chain, so as to increase the cascade number of the look-ahead carry logic structure in the carry delay chain 110 when the collected phase difference signal is greater than the preset signal value. For example, when the voltage amplitude is greater than 1 mV, the cascade quantity of the carry lookahead logic structure in the carry delay chain 110 is increased by 1.

[0046] It can be understood that, assuming that the phase detector output analog voltage amplitude range is -5V to +5V, set the crystal oscillator to output a square wave signal with a period of 5ns and a duty cycle of 50%. When the rising edge of the first signal leads the rising edge of the second signal by 90 degrees, the phase detector outputs a phase difference signal of +2.5V; when the rising edge of the first signal lags behind the rising edge of the second signal by 90 degrees, the phase detector outputs a phase difference signal of -2.5V. If the phase difference signal is positive, it indicates that the rising edge of the first signal leads the rising edge of the second signal, that is, the period of the square wave signal output by the crystal oscillator is less than 5ns and the frequency is greater than 200MHz; if the phase difference signal is negative, it indicates that the rising edge of the first signal lags behind the rising edge of the second signal, that is, the period of the square wave signal output by the crystal oscillator is greater than 5ns and the frequency is greater than 200MHz.

[0047] Each 1mV voltage amplitude indicates that there is a 0.036 degree phase difference between the first signal and the second signal. Calculated at 5ns, that is, each 1mV voltage amplitude indicates that there is a 0.0005ns time difference between the rising edge of the first signal and the rising edge of the second signal. If the phase difference signal is 100mV, the first signal period is 4.95ns and the frequency is 202.02MHz; if the phase difference signal is -100mV, the first signal period is 5.05ns and the frequency is 198.02MHz. Assume that the counting standard of the single-soldier operation and maintenance device is to count 200000000 clock rising edges every 5ns. If the crystal oscillator timing deviation is -0.05ns, the counting logic of the single-soldier operation and maintenance device can be adjusted to count 202020202 clock rising edges every 5ns. If the crystal oscillator timing deviation is +0.05ns, the counting logic of the single-soldier operation and maintenance device can be adjusted to count 198019801 clock rising edges every 5ns.

[0048] The technical solution of the embodiment of the present invention is to obtain the first signal generated by the crystal oscillator in the individual operation and maintenance device through a signal comparison module, and obtain the second signal output by the carry delay chain; the second signal is the signal obtained by inputting the first signal into the carry delay chain; the phase difference signal between the first signal and the second signal is determined through the signal comparison module; the timing deviation of the crystal oscillator is calculated according to the phase difference signal between the first signal and the second signal through the time deviation calculation module, and the time counting logic of the individual operation and maintenance device is adjusted according to the timing deviation. This solution solves the problems of difficulty in time calibration, low accuracy and high cost of the individual operation and maintenance device, and realizes automatic time calibration of the individual operation and maintenance device by calibrating the frequency change of the crystal oscillator through the inherent time delay of the carry delay chain, which is conducive to reducing the time calibration cost and improving the time calibration accuracy.

[0049] Embodiment 2

[0050] Figure 2 A flowchart of an automatic timing method based on a carry delay chain is provided for the second embodiment of the present invention. The method is executed by an automatic timing system, and the automatic timing system includes a carry delay chain, a signal comparison module, and a time offset calculation module. Figure 2 As shown, the method includes:

[0051] S210. Obtain a first signal generated by a crystal oscillator in the individual operation and maintenance device through a signal comparison module, and obtain a second signal output by a carry delay chain; wherein the second signal is a signal obtained by inputting the first signal into the carry delay chain.

[0052] This scheme can be executed by an automatic timing system, which includes a carry delay chain, a signal comparison module and a time deviation calculation module. The crystal oscillator in the single-soldier operation and maintenance device is connected to the carry delay chain, the carry delay chain is connected to the signal comparison module, and the signal comparison module is connected to the time deviation calculation module. Among them, the carry delay chain refers to a transmission delay line formed by cascading multiple carry-lookahead logic structures. The signal delay generated by the carry delay chain is fixed, so it can be used to correct the crystal oscillator delay.

[0053] S220. Determine a phase difference signal between the first signal and the second signal through a signal comparison module.

[0054] The carry delay chain can obtain the square wave signal generated by the crystal oscillator in the individual operation and maintenance device, that is, the first signal, and delay the first signal to obtain the second signal. The signal comparison module can obtain the first signal generated by the crystal oscillator in the individual operation and maintenance device, and at the same time obtain the second signal output by the carry delay chain, compare the phases of the first signal and the second signal, and output the phase difference signal between the first signal and the second signal. Specifically, the signal comparison module can be a phase detector. If the rising edge of the first signal leads the rising edge of the second signal, the signal comparison module outputs a positive polarity voltage; if the rising edge of the first signal lags behind the rising edge of the second signal, the signal comparison module outputs a negative polarity voltage. Among them, the amplitude of the output voltage can be proportional to the phase difference between the first signal and the second signal.

[0055] S230. Calculate the timing deviation of the crystal oscillator according to the phase difference signal between the first signal and the second signal through the time deviation calculation module, and adjust the time counting logic of the individual operation and maintenance device according to the timing deviation.

[0056] The time deviation calculation module can calculate the timing deviation of the crystal oscillator according to the phase difference signal between the first signal and the second signal, and adjust the time counting logic of the individual operation and maintenance device according to the timing deviation. Specifically, the time deviation calculation module can calculate the period or frequency of the first signal output by the crystal oscillator according to the phase difference signal between the first signal and the second signal, and compare the period of the first signal with the period of the crystal oscillator, or compare the frequency of the first signal with the frequency of the crystal oscillator to obtain the timing deviation of the crystal oscillator. According to the timing deviation of the crystal oscillator, the automatic time correction system can adjust the time counting logic of the individual operation and maintenance device. It can be understood that the time counting logic of the individual operation and maintenance device can be used to represent the mapping relationship between unit time and the number of clock cycles.

[0057] In this solution, optionally, the automatic time calibration system further includes an input selection module;

[0058] Before obtaining the first signal generated by the crystal oscillator in the individual operation and maintenance device through the signal comparison module, the method further includes:

[0059] The input signal of the signal comparison module is determined by the input selection module according to the working mode of the automatic timing system; wherein the working mode includes a calibration mode and an application mode.

[0060] In order to ensure the reliability of the automatic time calibration system, the automatic time calibration system can perform an automatic calibration operation before application. The automatic time calibration system can include two working modes, namely, calibration mode and application mode. It is easy to understand that the input signal of the signal comparison module is different in the calibration mode and the application mode.

[0061] Based on the above solution, the automatic timing system further includes a pulse generation module;

[0062] Before obtaining the first signal generated by the crystal oscillator in the individual operation and maintenance device through the signal comparison module, the method further includes:

[0063] Generate a reference pulse signal through a pulse generation module;

[0064] Through the input selection module, if the working mode of the automatic timing system is the application mode, the input signal of the signal comparison module is determined to be the first signal generated by the crystal oscillator in the individual operation and maintenance device and the second signal output by the carry delay chain; if the working mode of the automatic timing system is the calibration mode, the input signal of the signal comparison module is determined to be the reference pulse signal generated by the pulse generation module and the third signal output by the carry delay chain; wherein the third signal is the signal obtained by inputting the reference pulse signal into the carry delay chain.

[0065] In the calibration mode, the automatic timing system can use the pulse signal of the preset period generated by the pulse generation module as a reference pulse signal, input it into the carry delay chain, and calibrate the carry delay chain according to the third signal output by the carry delay chain and the reference pulse signal. Therefore, the input signal of the signal comparison module is the reference pulse signal generated by the pulse generation module and the third signal output by the carry delay chain.

[0066] In application mode, the automatic timing system can use the first signal generated by the crystal oscillator in the individual operation and maintenance device and the second signal output by the carry delay chain as input signals of the signal comparison module to calibrate the frequency of the crystal oscillator according to the inherent time delay of the carry delay chain.

[0067] In a feasible solution, after determining that the input signal of the signal comparison module is a first signal generated by a crystal oscillator in the individual operation and maintenance device and a second signal output by a carry delay chain, the method further includes:

[0068] Determine a phase difference signal between the reference pulse signal and the third signal by a signal comparison module;

[0069] The phase-time mapping relationship is determined by a time offset calculation module according to a phase difference signal between the reference pulse signal and the third signal.

[0070] The time deviation calculation module can determine the mapping relationship between the phase and time based on the period of the reference pulse signal and the phase difference signal between the reference pulse signal and the third signal. The phase-time mapping relationship can be characterized by analog signals such as voltage and current output by the signal comparison module. For example, a voltage amplitude of 1mV indicates that there is a phase difference of 0.036 degrees between the two input signals of the signal comparison module, and a voltage amplitude of 1mV indicates that there is a time difference of 0.0005ns between the rising edges of the two input signals, that is, a phase difference of 0.036 degrees corresponds to a time difference of 0.0005ns.

[0071] On the basis of the above scheme, the timing deviation of the crystal oscillator is calculated by the time deviation calculation module according to the phase difference signal between the first signal and the second signal, including:

[0072] The timing deviation of the crystal oscillator is calculated by the time deviation calculation module according to the phase difference signal between the first signal and the second signal based on the phase-time mapping relationship.

[0073] The time deviation calculation module can obtain the timing deviation of the crystal oscillator based on the phase-time mapping relationship according to the phase difference signal between the first signal and the second signal, and then adjust the time counting logic of the individual operation and maintenance device according to the timing deviation. Specifically, the time deviation calculation module can calculate the period or frequency of the first signal output by the crystal oscillator according to the phase-time mapping relationship according to the phase difference signal between the first signal and the second signal, and compare the period of the first signal with the period of the crystal oscillator, or compare the frequency of the first signal with the frequency of the crystal oscillator, to obtain the timing deviation of the crystal oscillator. According to the timing deviation of the crystal oscillator, the automatic time calibration system can adjust the time counting logic of the individual operation and maintenance device.

[0074] The technical solution of the embodiment of the present invention is to obtain the first signal generated by the crystal oscillator in the individual operation and maintenance device through a signal comparison module, and obtain the second signal output by the carry delay chain; the second signal is the signal obtained by inputting the first signal into the carry delay chain; the phase difference signal between the first signal and the second signal is determined through the signal comparison module; the timing deviation of the crystal oscillator is calculated according to the phase difference signal between the first signal and the second signal through the time deviation calculation module, and the time counting logic of the individual operation and maintenance device is adjusted according to the timing deviation. This solution solves the problems of difficulty in time calibration, low accuracy and high cost of the individual operation and maintenance device, and realizes automatic time calibration of the individual operation and maintenance device by calibrating the frequency change of the crystal oscillator through the inherent time delay of the carry delay chain, which is conducive to reducing the time calibration cost and improving the time calibration accuracy.

[0075] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0076] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An automatic timing system based on a carry delay chain, characterized in that: The automatic timing system includes a carry delay chain, a signal comparison module and a time deviation calculation module; The signal comparison module is used to obtain a first signal generated by a crystal oscillator in the individual operation and maintenance device, and to obtain a second signal output by a carry delay chain; wherein the second signal is a signal obtained by inputting the first signal into the carry delay chain; The signal comparison module is used to determine a phase difference signal between the first signal and the second signal; The time deviation calculation module is used to calculate the timing deviation of the crystal oscillator according to the phase difference signal between the first signal and the second signal, and adjust the time counting logic of the individual operation and maintenance device according to the timing deviation.

2. The automatic time calibration system according to claim 1, characterized in that: The automatic time calibration system also includes an input selection module; The input selection module is used to determine the input signal of the signal comparison module according to the working mode of the automatic timing system; wherein the working mode includes a calibration mode and an application mode.

3. The automatic time calibration system according to claim 2, characterized in that: The automatic timing system also includes a pulse generation module; The pulse generating module is used to generate a reference pulse signal; The input selection module is specifically used for: If the working mode of the automatic timing system is the application mode, it is determined that the input signal of the signal comparison module is a first signal generated by a crystal oscillator in the individual operation and maintenance device and a second signal output by a carry delay chain; If the working mode of the automatic timing system is the calibration mode, the input signal of the signal comparison module is determined to be the reference pulse signal generated by the pulse generation module and the third signal output by the carry delay chain; wherein the third signal is the signal obtained by inputting the reference pulse signal into the carry delay chain.

4. The automatic time calibration system according to claim 3, characterized in that: The signal comparison module is further used to determine a phase difference signal between the reference pulse signal and the third signal; The time offset calculation module is used to determine the phase-time mapping relationship according to the phase difference signal between the reference pulse signal and the third signal.

5. The automatic time calibration system according to claim 1, characterized in that: The time deviation calculation module is used to calculate the timing deviation of the crystal oscillator according to the phase difference signal between the first signal and the second signal based on the phase-time mapping relationship.

6. An automatic timing method based on a carry delay chain, characterized in that: The method is performed by an automatic time calibration system, which includes a carry delay chain, a signal comparison module and a time deviation calculation module; the method includes: Acquire a first signal generated by a crystal oscillator in the individual operation and maintenance device through a signal comparison module, and acquire a second signal output by a carry delay chain; wherein the second signal is a signal obtained by inputting the first signal into the carry delay chain; Determine a phase difference signal between the first signal and the second signal by a signal comparison module; The timing deviation of the crystal oscillator is calculated according to the phase difference signal between the first signal and the second signal through the time deviation calculation module, and the time counting logic of the individual operation and maintenance device is adjusted according to the timing deviation.

7. The automatic time calibration method according to claim 6, characterized in that: The automatic time calibration system also includes an input selection module; Before obtaining the first signal generated by the crystal oscillator in the individual operation and maintenance device through the signal comparison module, the method further includes: The input signal of the signal comparison module is determined by the input selection module according to the working mode of the automatic timing system; wherein the working mode includes a calibration mode and an application mode.

8. The automatic time calibration method according to claim 7, characterized in that: The automatic timing system also includes a pulse generation module; Before obtaining the first signal generated by the crystal oscillator in the individual operation and maintenance device through the signal comparison module, the method further includes: Generate a reference pulse signal through a pulse generation module; Through the input selection module, if the working mode of the automatic timing system is the application mode, the input signal of the signal comparison module is determined to be the first signal generated by the crystal oscillator in the individual operation and maintenance device and the second signal output by the carry delay chain; if the working mode of the automatic timing system is the calibration mode, the input signal of the signal comparison module is determined to be the reference pulse signal generated by the pulse generation module and the third signal output by the carry delay chain; wherein the third signal is the signal obtained by inputting the reference pulse signal into the carry delay chain.

9. The automatic time calibration method according to claim 8, characterized in that: After determining that the input signal of the signal comparison module is a first signal generated by a crystal oscillator in the individual operation and maintenance device and a second signal output by a carry delay chain, the method further includes: Determine a phase difference signal between the reference pulse signal and the third signal by a signal comparison module; The phase-time mapping relationship is determined by a time offset calculation module according to a phase difference signal between the reference pulse signal and the third signal.

10. The automatic time calibration method according to claim 6, characterized in that: The timing deviation of the crystal oscillator is calculated by the time deviation calculation module according to the phase difference signal between the first signal and the second signal, including: The timing deviation of the crystal oscillator is calculated by the time deviation calculation module according to the phase difference signal between the first signal and the second signal based on the phase-time mapping relationship.

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