High-precision clock synchronization device of power system

Abstract

The invention discloses a power system high-precision clock synchronization device, which comprises a microprocessor, a GPS module, a temperature detection module, a crystal oscillator frequency control module and a time output module, and is characterized in that the microprocessor is respectively connected with the GPS module, the temperature detection module, the crystal oscillator frequency control module and the time output module. According to the technical scheme, the microprocessor utilizes satellite time information transmitted by the GPS module to form clock synchronization of year, month, day, hour, minute and second, and when the connection with a satellite is abnormal in practical application, a voltage regulation unit in the microprocessor controls a voltage value output to the crystal oscillator frequency control module according to crystal oscillator temperature data; the crystal oscillator frequency control module controls the frequency of the output oscillation signal to be stable, and a counting unit of the microprocessor counts the number of pulses of the oscillation signal so as to realize a clock synchronization function; according to the technical scheme, two different clock synchronization modes are combined, and the situation that the clock synchronization effect is affected due to the poor network is avoided.

Description

Technical Field

[0001] The present invention relates to the field of electronic power technology, and more particularly to a high-precision clock synchronization device for a power system. Background Art

[0002] The power system is highly time-sensitive. Changes in parameters such as voltage, current, phase angle, and power angle are all based on time-based waveforms. High-precision time synchronization technology ensures the consistency of these parameters across the entire network, thereby improving the overall performance of the power system.

[0003] Current clock synchronization solutions for power systems include GPS (Global Positioning System) synchronization timing or PTP (Precision Time Protocol) event protocol timing. GPS timing is achieved by receiving timing signals sent by GPS satellites and transmitting time information to various devices in the power system. GPS synchronization technology requires receiving satellite signals to synchronize the clock. Therefore, when the signal is blocked or weak, the synchronization accuracy will be reduced. PTP is an Ethernet-based time synchronization protocol that achieves time synchronization between devices by transmitting time synchronization messages in the network. Its disadvantage is that due to network delays, the PTP protocol can only achieve sub-microsecond time synchronization accuracy and has high network requirements. The PTP protocol is sensitive to network delays and jitter, requires high-quality network environment support, and is complex to deploy.

[0004] This shows that the existing power system clock synchronization technology is not effective enough and cannot meet the control requirements of the power system. Summary of the Invention

[0005] In order to solve the above technical problems, the purpose of the present invention is to provide a high-precision clock synchronization device for a power system.

[0006] The technical solution adopted by the present invention to solve the problem is:

[0007] A high-precision clock synchronization device for an electric power system comprises a microprocessor, a GPS module, a temperature detection module, a crystal oscillator frequency control module and a time output module, wherein the microprocessor is connected to the GPS module, the temperature detection module, the crystal oscillator frequency control module and the time output module respectively;

[0008] The microprocessor comprises:

[0009] A signal detection unit, used to detect whether the GPS module receives satellite signals normally;

[0010] a first receiving unit, configured to receive time information transmitted by the satellite through the GPS module when the GPS module normally receives the satellite signal;

[0011] A clock synchronization unit, configured to complete clock synchronization of year, month, day, hour, minute, and second according to the time information, and generate a first standard second signal;

[0012] A second receiving unit, configured to receive crystal oscillator temperature data through the temperature detection module;

[0013] a voltage regulating unit, configured to control a voltage value output to the crystal oscillator frequency control module according to crystal oscillator temperature data, wherein the crystal oscillator frequency control module controls the frequency of the output oscillation signal to maintain stability according to the voltage value;

[0014] a counting unit, configured to count the number of pulses of the oscillation signal output by the crystal oscillator frequency control module when the GPS module cannot receive satellite signals, and generate a second standard second signal when the number of pulses reaches 1 / T;

[0015] The time output unit generates an interrupt response and sends time information to the outside according to the first standard second signal or the second standard second signal.

[0016] As a further improvement of the above technical solution, the present technical solution further includes an event record storage module, wherein the event record storage module is connected to the microprocessor;

[0017] The microprocessor further comprises:

[0018] The event interrupt unit is used to generate an interrupt response when receiving an external event pulse signal, output an event timestamp signal to the outside, and store the event information in the event record storage module.

[0019] As a further improvement of the above technical solution, the present technical solution further includes a power supply module, wherein the power supply module is electrically connected to each circuit module respectively;

[0020] The power supply module includes an offline power supply, an online power supply, and a power supply manager. The power supply manager is connected to the offline power supply and the online power supply, respectively. The power supply manager is configured to control the online power supply to be electrically connected to each circuit module when the online power supply is normal, and to control the offline power supply to be electrically connected to each circuit module when the online power supply is abnormal.

[0021] As a further improvement of the above technical solution, the microprocessor further includes:

[0022] A storage unit, configured to store a plurality of correction curves, wherein the plurality of correction curves are corresponding relationships between crystal oscillator frequencies and voltage values ​​at different temperatures;

[0023] The voltage regulating unit selects a suitable correction curve according to the crystal oscillator temperature data, and controls the voltage value output to the crystal oscillator frequency control module according to the selected correction curve.

[0024] As a further improvement of the above technical solution, the correction curve uses the crystal oscillator temperature data as the independent variable and the crystal oscillator frequency correction value as the dependent variable.

[0025] As a further improvement of the above technical solution, the correction curve is fitted based on the least squares method, and the fitting polynomial is set as follows:

[0026] D DAC =a m t n +a (m-1) t (n-1) +a (m-2) t (n-2) …+a1t 1 +a0

[0027] Among them, D DAC Indicates the crystal oscillator frequency correction value, t n It represents the temperature-related polynomial in the correction curve, t represents the crystal oscillator temperature data at a certain moment, n represents the fitting order, and the fitting coefficient a is solved by the least squares fitting method. m .

[0028] The beneficial effects of the present invention are as follows: in the present technical solution, the microprocessor uses the satellite time information transmitted by the GPS module for clock synchronization of year, month, day, hour, minute and second, and considering that in actual application, if an abnormality occurs in the satellite connection, the voltage regulating unit in the microprocessor controls the voltage value output to the crystal oscillator frequency control module according to the crystal oscillator temperature data, so that the crystal oscillator frequency control module controls the frequency of the output oscillation signal to maintain stability, and the counting unit of the microprocessor counts the number of pulses of the oscillation signal to realize the clock synchronization function; the present technical solution combines two different clock synchronization methods to avoid the influence of the clock synchronization effect due to poor network. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments.

[0030] Figure 1 It is a schematic diagram of the device module structure of the present invention. DETAILED DESCRIPTION

[0031] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but they should not be understood as limiting the scope of protection of the present invention.

[0032] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0033] In the description of the present invention, the meaning of "several" is one or more, the meaning of "many" is more than two, and the meanings of "greater than", "less than", "exceed" and "exceed" are not inclusive of the number itself, while the meanings of "above", "below", "within" and "include" are inclusive of the number itself. If there is a description of "first" or "second", it is only for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features. In the description of the present invention, unless otherwise clearly defined, the terms "set", "install", "connect" and "connect" should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific content of the technical solution.

[0034] Reference Figure 1 The present application discloses a high-precision clock synchronization device for a power system. A first embodiment thereof includes a microprocessor, a GPS module, a temperature detection module, a crystal oscillator frequency control module, and a time output module. The microprocessor is connected to the GPS module, the temperature detection module, the crystal oscillator frequency control module, and the time output module respectively.

[0035] The microprocessor comprises:

[0036] A signal detection unit, used to detect whether the GPS module receives satellite signals normally;

[0037] a first receiving unit, configured to receive time information transmitted by the satellite through the GPS module when the GPS module normally receives the satellite signal;

[0038] A clock synchronization unit, configured to complete clock synchronization of year, month, day, hour, minute, and second according to the time information, and generate a first standard second signal;

[0039] A second receiving unit, configured to receive crystal oscillator temperature data through the temperature detection module;

[0040] a voltage regulating unit, configured to control a voltage value output to the crystal oscillator frequency control module according to crystal oscillator temperature data, wherein the crystal oscillator frequency control module controls the frequency of the output oscillation signal to maintain stability according to the voltage value;

[0041] a counting unit, configured to count the number of pulses of the oscillation signal output by the crystal oscillator frequency control module when the GPS module cannot receive satellite signals, and generate a second standard second signal when the number of pulses reaches 1 / T;

[0042] The time output unit generates an interrupt response and sends time information to the outside according to the first standard second signal or the second standard second signal.

[0043] Specifically, the microprocessor in this embodiment uses the satellite time information transmitted by the GPS module for clock synchronization of year, month, day, hour, minute and second, and considering that in actual application, if an abnormality occurs in the connection between the device and the satellite, the voltage regulation unit in the microprocessor controls the voltage value output to the crystal oscillator frequency control module according to the crystal oscillator temperature data, so that the crystal oscillator frequency control module controls the frequency of the output oscillation signal to maintain stability, and the counting unit of the microprocessor counts the number of pulses of the oscillation signal to achieve the clock synchronization function; compared with the prior art, this embodiment combines two different clock synchronization methods to avoid the influence of poor network on the clock synchronization effect.

[0044] This embodiment uses the GPS module to receive UTC time information and second pulse signals, which are connected to the serial port and interrupt of the microprocessor respectively. The high-speed interrupt response of the microprocessor can achieve nanosecond clock synchronization. The clock error of this embodiment mainly comes from the error of the second pulse signal output by the GPS module and the interrupt response speed, counter response speed, and event pulse response speed. For this reason, this embodiment is also configured with the following function: by measuring the fixed values ​​of the above-mentioned various errors, the above-mentioned errors can be reduced through compensation.

[0045] As a further preferred embodiment, this embodiment further includes an event record storage module, and the event record storage module is connected to the microprocessor;

[0046] The microprocessor further comprises:

[0047] The event interrupt unit is used to generate an interrupt response when receiving an external event pulse signal, output an event timestamp signal to the outside, and store the event information in the event record storage module.

[0048] In this embodiment, the above settings realize the precise time synchronization function of each node in the distributed power system, and can accurately record the operation, failure, and recovery time of each node in the distributed power system, thereby realizing precise time management of each equipment in the power system.

[0049] This embodiment is a combined system that uses GPS synchronized timing and local clock correction to achieve high-precision clock synchronization and local timekeeping in the absence of a GPS signal. When the GPS signal is normal, this embodiment can use GPS for nanosecond-level clock synchronization. In the absence of a GPS signal or when the GPS signal is abnormal, a voltage-adjustable temperature-compensated crystal oscillator is used for frequency adjustment using nonlinear fitting interpolation, maintaining the clock system's accuracy at the microsecond level per hour. Furthermore, this embodiment utilizes the interrupt function of the microprocessor to accurately record the time of events occurring in the power system (including power system operation, failure, and recovery), and also provides event storage.

[0050] As a further preferred embodiment, this embodiment further includes a power supply module, wherein the power supply module is electrically connected to each circuit module respectively;

[0051] The power supply module includes an offline power supply, an online power supply, and a power supply manager. The power supply manager is connected to the offline power supply and the online power supply, respectively. The power supply manager is configured to control the online power supply to be electrically connected to each circuit module when the online power supply is normal, and to control the offline power supply to be electrically connected to each circuit module when the online power supply is abnormal.

[0052] As a further preferred implementation, in this embodiment, the microprocessor further includes:

[0053] A storage unit, configured to store a plurality of correction curves, wherein the plurality of correction curves are corresponding relationships between crystal oscillator frequencies and voltage values ​​at different temperatures;

[0054] The voltage regulating unit selects a suitable correction curve according to the crystal oscillator temperature data, and controls the voltage value output to the crystal oscillator frequency control module according to the selected correction curve.

[0055] In actual applications of this embodiment, when the GPS module cannot receive satellite signals or there is an abnormality in the satellite signal, this embodiment relies on counting the number of oscillation pulses generated by the crystal oscillator device configured therein to implement the clock synchronization function. The crystal oscillator frequency control module described in this embodiment is configured with a temperature-compensated crystal oscillator, which is used as the basic clock source. Considering that the oscillation signal frequency output of the temperature-compensated crystal oscillator is not fixed and its frequency is easily affected by external factors such as temperature, this embodiment applies a control voltage to it to adjust its frequency output.

[0056] As a further preferred implementation, in this embodiment, the correction curve uses the crystal oscillator temperature data as the independent variable and the crystal oscillator frequency correction value as the dependent variable.

[0057] As a further preferred embodiment, in this embodiment, the correction curve is fitted based on the least squares method, and the fitting polynomial is set as follows:

[0058] D DAC =a m t n +a (m-1) t (n-1) +a (m-2) t (n-2) ...+a1t 1 +a0

[0059] Among them, D DAC Indicates the crystal oscillator frequency correction value, t n It represents the temperature-related polynomial in the correction curve, t represents the crystal oscillator temperature data at a certain moment, n represents the fitting order, and the fitting coefficient a is solved by the least squares fitting method. m .

[0060] In this embodiment, in order to evaluate the fitting effect, the Pearson correlation is used to measure the goodness of fit. It can measure the relationship between two continuous signals over time, and the linear relationship between them is represented by the numbers -1 (negative correlation), 0 (no correlation), and 1 (perfect correlation). In this embodiment, the fitting curves of different orders are solved by the least squares method, and the Pearson cross-correlation is used to calculate their goodness of fit. The results show that after the 10th order, the goodness of fit changes little, and the correction curve is located between the heating and cooling processes.

[0061] The above are only preferred embodiments of the present invention and are not intended to limit the patent scope of the present invention. All equivalent structural transformations made based on the contents of the present invention's description and drawings, or directly or indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A high-precision clock synchronization device for a power system, characterized by: It includes a microprocessor, a GPS module, a temperature detection module, a crystal oscillator frequency control module and a time output module, wherein the microprocessor is connected to the GPS module, the temperature detection module, the crystal oscillator frequency control module and the time output module respectively; The microprocessor comprises: A signal detection unit, used to detect whether the GPS module receives satellite signals normally; a first receiving unit, configured to receive time information transmitted by the satellite through the GPS module when the GPS module normally receives the satellite signal; A clock synchronization unit, configured to complete clock synchronization of year, month, day, hour, minute, and second according to the time information, and generate a first standard second signal; A second receiving unit, configured to receive crystal oscillator temperature data through the temperature detection module; a voltage regulating unit, configured to control a voltage value output to the crystal oscillator frequency control module according to crystal oscillator temperature data, wherein the crystal oscillator frequency control module controls the frequency of the output oscillation signal to maintain stability according to the voltage value; a counting unit, configured to count the number of pulses of the oscillation signal output by the crystal oscillator frequency control module when the GPS module cannot receive satellite signals, and generate a second standard second signal when the number of pulses reaches 1 / T; The time output unit generates an interrupt response according to the first standard second signal or the second standard second signal and sends time information to the outside through the time output module.

2. The high-precision clock synchronization device for a power system according to claim 1, characterized in that: It also includes an event record storage module, which is connected to the microprocessor.

3. A high-precision clock synchronization device for a power system according to claim 2, characterized in that: The microprocessor further comprises: The event interrupt unit is used to generate an interrupt response when receiving an external event pulse signal, output an event timestamp signal to the outside, and store the event information in the event record storage module.

4. The high-precision clock synchronization device for a power system according to claim 1, characterized in that: It also includes a power supply module, which is electrically connected to each circuit module respectively; The power supply module includes an offline power supply, an online power supply, and a power supply manager. The power supply manager is connected to the offline power supply and the online power supply, respectively. The power supply manager is configured to control the online power supply to be electrically connected to each circuit module when the online power supply is normal, and to control the offline power supply to be electrically connected to each circuit module when the online power supply is abnormal.

5. The high-precision clock synchronization device for a power system according to claim 1, characterized in that: The microprocessor further comprises: A storage unit, configured to store a plurality of correction curves, wherein the plurality of correction curves are corresponding relationships between crystal oscillator frequencies and voltage values ​​at different temperatures; The voltage regulating unit selects a suitable correction curve according to the crystal oscillator temperature data, and controls the voltage value output to the crystal oscillator frequency control module according to the selected correction curve.

6. The high-precision clock synchronization device for a power system according to claim 5, characterized in that: The correction curve uses the crystal oscillator temperature data as the independent variable and the crystal oscillator frequency correction value as the dependent variable.

7. The high-precision clock synchronization device for a power system according to claim 6, characterized in that: The correction curve is fitted based on the least squares method, and the fitting polynomial is set as follows: D DAC =a m t n +a (m-1) t (n-1) +a (m-2) t (n-2) ...+a1t 1 +a0 Among them, D DAC Indicates the crystal oscillator frequency correction value, t n It represents the temperature-related polynomial in the correction curve, t represents the crystal oscillator temperature data at a certain moment, n represents the fitting order, and the fitting coefficient a is solved by the least squares fitting method. m .

Images