Method for adjusting time service time of traffic signal lamp

Abstract

The invention discloses a traffic signal lamp time service time adjusting method, and relates to the field of intelligent traffic, and the method comprises the steps: signal lamp equipment obtains a satellite time service data packet and a central time service data packet in real time in the operation process, and the satellite time service data packet and the central time service data packet comprise time service time provided by various time service modes; respectively calculating the stability magnitude P of each time service mode; when a time service deviation exists between the time service time provided by the time service mode selected by the equipment and the timing time of the local machine, determining the maximum duration allowed to be adjusted per second in the time service mode according to the corresponding P value and the time service deviation duration; and the equipment adjusts the time service time according to the maximum duration allowed to be adjusted per second, and calculates the maximum duration allowed to be adjusted per second at the next time until the time service deviation is eliminated. When the intelligent signal lamp equipment uses wireless or bus communication, precision time service can be realized among the equipment, and risks caused by time asynchronization of the signal control equipment are reduced as much as possible.

Description

Technical Field

[0001] The invention relates to the field of intelligent transportation, and in particular to a method for adjusting the timing of a traffic signal light. Background Art

[0002] Current traffic products, especially those related to signal systems, do not have a unified standard for the management and application of timing data. Most of them use a simple single timing method, such as using a single satellite (GPS, Beidou) for timing, or using a central virtual signal machine for timing (referred to as central timing); or a priority arrangement method, such as the central timing priority is higher than the satellite timing. When both timing data exist, the priority is selected. This type of extensive timing method can basically meet the use requirements of traditional signal machines. Since a single intersection is controlled by a signal machine, and the signal light is controlled by controlling the conduction and disconnection of 220V, even if the signal machine has a timing deviation or timing loss, it will not affect the execution of the release plan of a single intersection, and will not cause serious traffic safety hazards such as green conflicts. It only affects the coordinated control between multiple intersections. However, with the development of signal systems, especially the development of intelligent signal lights connected by wireless or bus forms, the original signal system architecture has been broken, and the demand for time accuracy has also changed.

[0003] After the introduction of concepts such as wireless smart traffic lights, the intersection-level traffic lights will be removed and replaced by independently networked smart traffic lights. At this time, the timing stability is improved from seconds to ten milliseconds. Since the traffic lights at an intersection need to be timed individually and run a set of release schemes at the same time, the switching of each light needs to be within ten milliseconds, otherwise it will cause short-term green conflicts and other situations, which will pose certain risks to the judgment of illegal capture and actual driving safety. The central timing data packet used for time synchronization needs to be transmitted through the network. The wired network is affected by the stability of the network, and there is a certain degree of packet loss and delay. In particular, the wireless network will be more sensitive to external interference, and the overall delay will be greatly increased; and the satellite timing will cause weak signals due to weather, location and other issues, causing the receiving device to lose the timing data packet for a long time, and then the timing interruption problem will occur.

[0004] After the traffic lights are upgraded to be intelligent, more functions can be integrated to make the control and management of signals more intelligent. However, due to the communication through wireless and bus forms, data delays, errors and other problems will inevitably occur, which will have a serious impact on signal control. However, if the accuracy of the timing of each device can be guaranteed, the traffic lights can work for a long time in a state disconnected from the signal control end, which can solve the above problems well. Summary of the invention

[0005] In response to the above-mentioned problems and technical needs, the inventors have proposed a method for adjusting the timing of traffic lights, so that when the intelligent traffic light devices use wireless or bus communication, the timing between each device can be accurate to ten milliseconds. This method can also cope with timing anomalies caused by environmental, communication, and hardware failures, and minimize the risks of signal control equipment caused by time asynchrony.

[0006] For smart traffic lights controlled wirelessly, timing will be the core parameter for their stable operation. Since each group of traffic lights connected wirelessly, the timing data transmission is susceptible to distance, external interference, and the data processing speed of the device, packet loss occurs, and transmission delay is inevitable. These are practical technical problems that cannot be changed, which makes it impossible for wireless traffic lights to switch the light color using real-time control. The switching of all signals of smart traffic lights is controlled by preset time first, rather than real-time control instructions. Switching control is performed by preset time, requiring the timing between each device to reach an accuracy of ten milliseconds, and no time jump problem is allowed, otherwise it will cause confusion of traffic light release signals and even cause serious traffic accidents. However, it can avoid the green conflict and release confusion caused by untimely switching due to signal loss, network delay and other problems.

[0007] Satellite timing and some RTC clock chips use second-level pulse timing, and smart traffic light equipment uses internal beats for millisecond timing. At this time, the sampling point per second may be affected by the system operation, and the sampling time will have a certain deviation. Because of the deviation of the sampling point or the reading point, it is easy to cause a 1-second error in the time points of the two samplings. For example, the first sampling position is at the beginning of the current "second" and the second sampling is at the end of the current "second", which will cause the two sampling times to be consistent. At this time, a 1-second error will occur between multiple devices at the same intersection. When the second-level error is reflected in the light color switching in the application scenarios of independent smart traffic lights at the intersection, it will cause serious safety hazards to traffic signal control.

[0008] To solve the above problems, the technical solution of the present invention is as follows:

[0009] A method for adjusting the timing of a traffic signal light comprises the following steps:

[0010] During operation, the signal light equipment obtains satellite timing data packets and center timing data packets in real time, which include the timing time provided by various timing methods;

[0011] Calculate the stability value P of each timing mode respectively;

[0012] When the timing time provided by the timing mode selected by the device has a timing deviation from the local timing time, the maximum adjustment time allowed per second under the timing mode is determined according to the corresponding P value and the timing deviation duration;

[0013] The device adjusts the timing according to the maximum adjustment duration allowed per second, and calculates the next maximum adjustment duration allowed per second until the timing deviation is eliminated.

[0014] A further technical solution is that the method for calculating the stability value P of various timing modes is the same. For any timing mode, the method includes:

[0015] Record the time difference between each time synchronization and the last time synchronization, record n ​​times, respectively Δt a1 to Δt an ;

[0016] Calculate the device beat timing between each time synchronization and the previous time synchronization, calculate n times, respectively Δt b1 to Δt bn ;

[0017] Calculate the stability value P, expressed as:

[0018]

[0019] Among them, when a certain timing method is more stable, the calculated P value is closer to 0;

[0020] The device beat timing is defined as the product of the number of beats counted by the device between two timing intervals and the actual duration corresponding to each beat.

[0021] A further technical solution is to determine the maximum adjustment duration allowed per second according to the corresponding P value and the timing deviation duration, including:

[0022] The maximum adjustment duration allowed per second is t pmax , and its calculation formula is:

[0023]

[0024] Among them, t a The timing time provided by the timing mode selected by the device, t b The time for this machine, t c is the basic value of the duration allowed to be adjusted per second, and k is a preset constant;

[0025] Select the corresponding t according to the duration of the timing deviation pmax According to the formula, when the device adjusts the timing time according to the maximum adjustment time allowed per second, it is divided into timing time suppression adjustment and timing time fast adjustment according to the size of P value.

[0026] A further technical solution is that when the device adjusts the timing time according to the maximum adjustment time allowed per second, it is divided into timing time suppression adjustment and timing time rapid adjustment according to the size of the P value, including:

[0027] When the P value is less than 1, it corresponds to a low P value, and the timing data is relatively stable at this time. Otherwise, it corresponds to a high P value, and the timing data is unstable at this time.

[0028] When the timing deviation is less than 1s under high P value, the calculated t pmax Smaller to achieve timing time suppression adjustment; when the timing deviation duration is not less than 1s under high P value, the calculated t pmax Amplified to enable rapid adjustment of timing;

[0029] When the timing deviation is less than 1s under low P value, the calculated t pmax is amplified to achieve rapid adjustment of the timing time; when the timing deviation duration is not less than 1s under high P value, the calculated t pmax Small enough to achieve timing suppression adjustment.

[0030] Its further technical solution is that the method further comprises:

[0031] During the startup process, the signal light equipment obtains at least the satellite timing data packet and the center timing data packet in real time, which includes the timing time provided by various timing methods;

[0032] When the deviation between the center timing time and the satellite timing time is less than the preset deviation value, the device uses the satellite timing time;

[0033] Calculate the data dispersion P of each timing mode respectively i ;

[0034] When the P of various timing modes i When it does not exceed the set threshold, the actual duration corresponding to each beat under each timing mode is calculated respectively, which is used to calculate the device beat timing between each timing and the previous timing under each timing mode;

[0035] Among them, the device counts according to the external reference clock input, and the cumulative number of clocks required for a single beat is recorded as one beat; the device beat timing is defined as the product of the number of beats counted by the device between two timing intervals and the actual duration corresponding to each beat.

[0036] The further technical solution is to calculate the data dispersion P of various timing modes. i The method is the same as that for any timing mode, the method includes:

[0037] Record the time difference between each time synchronization and the last time synchronization, record n ​​times in total, respectively Δt a1 to Δt an ;

[0038] Record the number of device beats between each time synchronization and the last time synchronization, record n ​​times in total, respectively m a1 to m an ;

[0039] Calculate the data dispersion P i , expressed as:

[0040]

[0041] Among them, M t Indicates the theoretical time corresponding to each beat; when a timing method is more stable, the calculated P i The closer to 0.

[0042] Its further technical solution is that the formula for calculating the actual duration corresponding to each beat under various timing modes is the same, expressed as:

[0043] M j =Δt aj / m aj ,j=1,2……n

[0044] Among them, M j is the actual duration of each beat calculated for the jth time, Δt aj is the time difference between the current time service and the previous time service recorded for the jth time, m aj The number of device beats between the current timing recorded for the jth time and the previous timing.

[0045] Its further technical solution is that the method further comprises:

[0046] When satellite timing data packets are lost or abnormal during operation of the signal light equipment, the local timing time is compared with the recorded loss / abnormal time;

[0047] If the time difference between the two is within the preset range and there is a central timing data packet, the central timing time is used and updated to the original central timing time plus the average time difference of the original satellite timing time and the original central timing time, and the maximum adjustment time allowed per second is determined according to the P value of the central timing mode and the timing deviation duration to adjust the timing time;

[0048] If the time difference between the two exceeds the preset range, the device is judged to be abnormal.

[0049] Its further technical solution is that the method further comprises:

[0050] When the central timing data packet is lost or abnormal during the operation of the signal light equipment, the satellite timing time is used, and the maximum adjustment time allowed per second is determined according to the P value of the satellite timing method and the timing deviation duration to adjust the timing time;

[0051] If the satellite timing data packet also shows an abnormality and lasts for a certain period of time, the device is judged to be abnormal.

[0052] Its further technical solution is that the method further comprises:

[0053] When a short power outage occurs during the operation of the signal light device, the RTC clock time is compared with the last recorded operation time of the device;

[0054] If the time difference between the two is less than the preset power-off threshold, the RTC clock time is used as the timing time until power is restored, and the timing time is adjusted through the real-time satellite timing data packets and center timing data packets.

[0055] The beneficial technical effects of the present invention are:

[0056] This method does not require additional equipment, and only uses satellite timing, center timing data and RTC clock time. By designing a good timing adjustment method, the accuracy of timing and the stable operation of the signal control system are guaranteed to the maximum extent, avoiding timing jumps and switching anomalies, as well as the handling methods for failures such as packet loss or anomalies in various parts of the timing-related hardware. A system design is carried out to improve the applicability of the method. After this method is applied to wireless intelligent traffic lights and bus signal machines, it will greatly improve the landing ability of such products in an economical way and provide technical support for the future development of traffic signal control. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 This is a device structure diagram of the wireless intelligent signal light provided in this application.

[0058] Figure 2 This is a flow chart of a method for adjusting the timing of a traffic signal provided by the present application.

[0059] Figure 3 This is a timing flow chart of the boot process provided by this application. DETAILED DESCRIPTION

[0060] The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings.

[0061] This embodiment describes a method for adjusting the timing of a traffic light by solving the timing problem of a wireless intelligent traffic light, wherein the timing sources of the wireless intelligent traffic light include central timing (wireless form), satellite timing (GPS or Beidou), and a clock chip (RTC) built into the device. The core content of this method is the stability of each timing data, and the error between each data value and the actual timing is obtained by calculation, and an adjustment method is used to well suppress the adjustment of unstable timing, while improving the adjustment speed of stable timing. In this way, the timing stability at the intersection level and the regional level, and the stable execution of the traffic release plan are achieved. At the same time, when some timing deviations or losses occur, this method also provides a set of timing switching methods to ensure that the device time does not jump and achieve stable transition. This method is not only applicable to wireless intelligent traffic lights, but also to non-real-time controlled signal machines (bus control) and traditional real-time controlled signal machines.

[0062] like Figure 1 As shown in the figure, the intelligent traffic light system is characterized in that the signal light equipment communicates with the central server through 5G, there is no physical signal machine at the intersection, and the signal machine is virtualized into the central system. Its advantage is that the intersection no longer requires complex wiring, and the traffic signal controller is omitted, which greatly reduces the construction cost. At the same time, the signal light is connected to the center through 5G, which can transmit more data. Through the intelligent signal light controller, the center can more directly monitor the various parameters of the signal light, not limited to the ambient brightness, equipment power consumption, equipment posture, equipment internal environment, etc., and can even provide signal transmission links for signal light peripheral equipment, such as traffic flow radar, surveillance cameras, etc., providing a realization platform for the intelligence of the signal light. In order to ensure the coordinated control of each signal light at the intersection and each signal light in the area, it is necessary to perform timing management through the following method. This method provides a technical basis for the implementation of the wireless signal light + virtual signal machine solution.

[0063] Please refer to Figure 2 As shown, a method for adjusting the timing of a traffic signal light specifically comprises the following steps:

[0064] Step 2: During operation, the signal light equipment obtains satellite timing data packets and center timing data packets in real time, which include the timing times provided by various timing methods.

[0065] Step 4: Calculate the stability value P of each timing mode respectively.

[0066] The method for calculating the stability value P of various timing modes is the same. For any timing mode, the steps specifically include: recording the timing data of each channel (satellite timing time, center timing time) respectively, and recording the time difference between each timing and the previous timing by rolling recording, recording n times, respectively Δt a1 to Δtan Calculate the device beat timing between each time synchronization and the previous time synchronization, calculate n times, respectively Δt b1 to Δt bn , the device beat timing can be understood as the device counting according to the external input reference clock. When the number of clocks required for a single beat is accumulated, it is recorded as a beat. The device beat timing is calculated by the number of beats, that is, the product of the number of beats counted by the device between two time intervals and the actual duration corresponding to each beat. The actual duration corresponding to each beat can be calculated during the device startup process, which will be explained in detail later. It should be noted that due to the accuracy deviation of the device reference clock in different environments, the beat timing time obtained by the device based on the reference clock is not the actual natural time.

[0067] The stability value P is calculated from the above data and is expressed as:

[0068]

[0069] The more stable a timing mode is, the closer the calculated P value is to 0; when the P value exceeds the preset threshold, the device will determine that the corresponding timing mode is unstable and its timing data is unavailable.

[0070] Step 6: When the timing time provided by the timing mode selected by the device has a timing deviation from the local timing time, the maximum adjustment time allowed per second under the timing mode is determined according to the corresponding P value and the timing deviation duration, which is recorded as t pmax , and its calculation formula is:

[0071]

[0072] Where: t a The timing time provided by the timing mode selected by the device; t b The timing time of this machine can be obtained by using the actual number of beats; t c The basic value of the duration allowed to be adjusted per second, usually a fixed constant; k is a preset constant, ranging from 10-100.

[0073] Step 8: The device adjusts the timing time according to the maximum adjustment time allowed per second, and executes step 6 to calculate the next maximum adjustment time allowed per second until the timing deviation is eliminated.

[0074] Select the corresponding t according to the duration of the timing deviation pmax According to the formula, when the device adjusts the timing time according to the maximum adjustment time allowed per second, it is divided into timing time suppression adjustment and timing time rapid adjustment according to the size of the P value. If the P value is less than 1, it corresponds to the low P value situation. At this time, the timing data is relatively stable. Otherwise, it corresponds to the high P value situation. At this time, the timing data is unstable. The different situations are described as follows:

[0075] When the timing deviation duration is less than 1s under high P value, the larger the P value, the higher the calculated t pmax If the timing deviation is too small, it is considered that the small timing deviation adjustment demand is due to the normal fluctuation caused by the instability of the timing mode, and no rapid adjustment is required. Therefore, a smaller t pmax To achieve timing time suppression adjustment. When the timing deviation duration is not less than 1s under high P value, the larger the P value, the calculated t pmax is amplified. At this time, if a large timing deviation is required, a larger t pmax This allows for rapid adjustment of timing time, thereby ensuring a rapid transition of the equipment from unstable to stable, allowing timing deviations to be quickly adjusted.

[0076] When the timing deviation duration is less than 1s under low P value, the smaller the P value, the more accurate the calculated t pmax is amplified. At this time, it is believed that the timing is not prone to abnormal fluctuations, but there is still adjustment of the accumulated error in the timing, which is an inevitable adjustment. Therefore, a larger t pmax In order to achieve rapid adjustment of the timing time, the device time can be quickly fine-tuned to ensure the time synchronization between devices. When the timing deviation duration is not less than 1s under high P value, the smaller the P value, the calculated t pmax If the timing deviation is too small, it is considered that the timing is stable. The occasional large timing deviation adjustment demand may be caused by anomalies. Therefore, a smaller t pmax To achieve the timing suppression adjustment, the calculated t pmax , will be smaller than the t corresponding to the large fluctuation when the high P value occurs pmax Calculated value.

[0077] When adjusting the timing time, if the obtained timing time has a 20ms error with the local timing time, t pmax After calculation, it is 15ms. Therefore, the maximum difference time allowed to be adjusted in the current second is 15ms, and the error value after adjustment is 5ms. The above calculation process is continued in the next second. If the maximum adjustment time allowed after the next calculation is 10ms, but the current error value of 5ms is less than 10ms, then the adjustment is made according to 5ms.

[0078] Since various timing modes will not experience large jumps when they work normally, jumps are generally caused by network delays and communication anomalies, but cumulative error adjustment is not excluded. Therefore, in this embodiment, when the timing time is inconsistent with the device time and the time needs to be adjusted or when the time needs to be corrected suddenly, a P value and t are quoted according to the timing deviation. pmaxThe calculation method is adjusted through multiple adjustments. On the one hand, it ensures that the time is switched from second-level adjustment to millisecond-level adjustment during the adjustment process. Through multiple fine-tuning, the release plan confusion caused by time jumps can be avoided to ensure the synchronization of traffic lights between devices; on the other hand, some sudden deviations may be caused by various timing data transmission delays, data output jams, and data processing abnormalities. Such deviations are generally not continuous, or even if they are continuous, they can be suppressed and filtered through slow adjustment.

[0079] For the timing switching problem, an analysis and selection is made based on the characteristics of each timing source. The characteristics of satellite timing are high accuracy but poor stability; the characteristics of central timing are connecting all devices for easy synchronization, but network delays will lead to relatively poor accuracy and general stability; the problem with the RTC clock chip is that the signal control equipment is generally outdoors, and the outdoor temperature has a certain impact on the crystal oscillator. Its error will be accumulated and reflected in the on and off of the signal light, but its signal is relatively stable. Based on this, a set of timing switching methods is designed, which is divided into timing selection during the startup process and timing selection during the operation process. A method for adjusting the timing time of a traffic light also includes the following timing selection content for the startup process before step 2:

[0080] Please refer to Figure 3 As shown, first, the signal light device obtains the satellite timing data packet, the central timing data packet and the RTC clock chip timing data packet in real time during the boot process. That is, the device is turned on, waits for the satellite timing receiving module to start, and requests the central timing data and the RTC clock chip timing data. The device receives each timing data packet, which contains the timing time provided by various timing methods.

[0081] Secondly, when the deviation between the central timing time and the satellite timing time is less than the preset deviation value, the device uses the satellite timing time in hours, minutes, and seconds, and uses the pulse signal for millisecond timing, and improves the time consistency between devices through the satellite pulse signal. At this time, the device records the satellite timing, central timing, and RTC clock chip timing data, and calculates the data dispersion P of each timing mode respectively. i . Calculate the data dispersion P of various timing modes i The method is the same as that for any timing mode, specifically including: recording the time difference between each timing and the previous timing, a total of n times, respectively Δt a1 to Δt an . Record the number of device beats between each time synchronization and the last time synchronization, record n ​​times in total, respectively m a1 to m an . Calculate the data dispersion P i , expressed as:

[0082]

[0083] Among them, M t Indicates the theoretical time corresponding to each beat. i When ≤1, it indicates that the timing mode is stable, and the timing data obtained subsequently or the timing data recorded above can be used to calculate the relationship between the device beat number and the timing data.

[0084] Optionally, the preset deviation value is recommended to be set to ±200ms. This value can also be set separately based on the average network delay. The greater the delay, the greater the preset deviation value.

[0085] Finally, when the P of various timing methods i When it does not exceed the set threshold (for example, 1), the actual duration corresponding to each beat under each timing mode is calculated respectively. The formula for calculating the actual duration corresponding to each beat under each timing mode is the same, which is expressed as:

[0086] M j =Δt aj / m aj ,j=1,2……n

[0087] Among them, M j is the actual duration of each beat calculated for the jth time, Δt aj is the time difference between the current time service and the previous time service recorded for the jth time, m aj The number of device beats between the current timing recorded for the jth time and the previous timing.

[0088] Calculate the M values ​​of satellite timing, center timing, and RTC clock timing respectively, which are used to calculate the device beat timing Δt between each timing and the previous timing under various timing modes in step 4 bj =M j *m bj , where m bj The number of beats counted by the device between the two timing signals before and after the jth one. Each timing signal needs to be calculated separately. b .

[0089] At the same time, at the first millisecond of each second, data is written into the RTC clock chip, which performs time backup, and the M value of the RTC clock timing is calculated to ensure that the written data is reliable. When the following situations occur: 1) the deviation between the central timing time and the satellite timing time exceeds the preset deviation value (i.e. >±200MS), 2) the central timing data packet is lost (wireless network abnormality, server software abnormality), 3) the satellite timing data packet is lost, 4) the RTC clock data packet is lost. The above situations during the boot process are judged as abnormal device startup, and the single intelligent signal light flashes yellow or turns off the light.

[0090] A method for adjusting the timing of a traffic signal light, after step 8, further includes the following timing selection content of the operation process:

[0091] When the equipment is operating normally, the equipment timing is based on the satellite timing, and the P value and t of the satellite timing and the center timing are calculated continuously. pmax ; Simultaneously calculate the average time difference t between satellite timing time and center timing time u , these data RTC clock write operation at a certain interval period. If all kinds of timing data are not lost, the device will adjust the timing time through the method of step 2 to step 8. When the following situations occur, the following processing will be carried out:

[0092] ① When the satellite timing data packet is lost or abnormal during the operation of the signal light equipment (P i >1), compare the local timing time with the recorded loss / abnormal time. If the time difference between the two is within the preset range, that is, the satellite loss time is short, and there is a central timing data packet, the central timing time is used and updated to the original central timing time t a Add the average time difference t u , and determine the maximum adjustment time allowed per second according to the P value of the central timing mode and the timing deviation duration, so as to adjust the timing time according to steps 6 and 8. If the time difference between the two exceeds the preset range, that is, the satellite is lost for a long time, the device is judged to be abnormal.

[0093] ② When the central timing data packet is lost or abnormal during the operation of the signal light equipment (P i >1), use the satellite timing time and stabilize the timing. Determine the maximum adjustment time allowed per second based on the P value of the satellite timing mode and the timing deviation duration, and adjust the timing time according to steps 6 and 8. i >1) and exceeds a certain time, the device is considered abnormal.

[0094] ③ When a short power outage occurs during the operation of the signal light device, the device starts to read the RTC clock signal and compares the RTC clock time with the recorded last operating time of the device. If the time difference between the two is less than the preset power-off threshold, the RTC clock time is used as the timing time, and its second-level starting position is confirmed through multiple readings, and this time is used as a transition. After the power is restored, the timing time is adjusted by re-executing steps 2 to 8 through the real-time satellite timing data packet and the center timing data packet. Through this method, after a short power outage, the device timing time can be quickly adjusted and restored while ensuring the accuracy of operation.

[0095] The above is only a preferred embodiment of the present application, and the present invention is not limited to the above embodiments. It is understood that other improvements and changes directly derived or associated by those skilled in the art without departing from the spirit and concept of the present invention should be considered to be included in the protection scope of the present invention.

Claims

1. A method for adjusting the timing of a traffic signal light, characterized in that: The method comprises: During operation, the signal light equipment obtains satellite timing data packets and center timing data packets in real time, which include the timing time provided by various timing methods; Calculate the stability value P of each timing mode respectively; When there is a timing deviation between the timing time provided by the timing mode selected by the device and the local timing time, the maximum adjustment time allowed per second under the timing mode is determined according to the corresponding P value and the timing deviation time; The device adjusts the timing time according to the maximum duration allowed for adjustment per second, and calculates the maximum duration allowed for adjustment per second for the next time until the timing deviation is eliminated.

2. The method for adjusting the timing of a traffic signal light according to claim 1, characterized in that: The method for calculating the stability value P of each timing mode is the same. For any timing mode, the method includes: Record the time difference between each time synchronization and the last time synchronization, record n ​​times, respectively Δt a1 to Δt an ; Calculate the device beat timing between each time synchronization and the previous time synchronization, calculate n times, respectively Δt b1 to Δt bn ; Calculate the stability value P, expressed as: Among them, when a certain timing method is more stable, the calculated P value is closer to 0; The device beat timing is defined as the product of the number of beats counted by the device between two timing intervals and the actual duration corresponding to each beat.

3. The method for adjusting the timing of a traffic signal light according to claim 1, characterized in that: Determining the maximum duration allowed for adjustment per second according to the corresponding P value and the duration of the timing deviation includes: The maximum duration allowed for adjustment per second is denoted as t pmax , and its calculation formula is: Among them, t a The timing time provided by the timing mode selected for the device, t b The time for the local timer, t c is the basic value of the duration allowed to be adjusted per second, and k is a preset constant; Select the corresponding t according to the duration of the timing deviation pmax Formula, when the device adjusts the timing time according to the maximum adjustment time allowed per second, it is divided into timing time suppression adjustment and timing time rapid adjustment according to the size of P value.

4. The method for adjusting the timing of a traffic signal light according to claim 3, characterized in that: When the device adjusts the timing time according to the maximum adjustment duration allowed per second, it is divided into timing time suppression adjustment and timing time rapid adjustment according to the size of the P value, including: When the P value is less than 1, it corresponds to a low P value, and the timing data is relatively stable at this time. Otherwise, it corresponds to a high P value, and the timing data is unstable at this time. When the timing deviation duration is less than 1s under the high P value, the calculated t pmax is too small to achieve the timing time suppression adjustment; when the timing deviation duration is not less than 1s under the high P value, the calculated t pmax is amplified to achieve rapid adjustment of the timing time; When the timing deviation duration is less than 1s under the low P value, the calculated t pmax is amplified to achieve rapid adjustment of the timing time; when the timing deviation duration is not less than 1s under the high P value, the calculated t pmax Small enough to achieve the timing suppression adjustment.

5. The method for adjusting the timing of a traffic signal light according to claim 1 or 2, characterized in that: The method further comprises: During the startup process, the signal light equipment obtains at least the satellite timing data packet and the center timing data packet in real time, which includes the timing time provided by various timing methods; When the deviation between the central timing time and the satellite timing time is less than a preset deviation value, the device adopts the satellite timing time; Calculate the data dispersion P of each timing mode respectively i ; When the P of various timing modes i When it does not exceed the set threshold, the actual duration corresponding to each beat under each timing mode is calculated respectively, which is used to calculate the device beat timing between each timing and the previous timing under each timing mode; Among them, the device counts according to the external reference clock input, and the accumulated number of clocks required for a single beat is recorded as a beat; the device beat timing is defined as the product of the number of beats counted by the device between two timing intervals and the actual duration corresponding to each beat.

6. The method for adjusting the timing of a traffic signal light according to claim 5, characterized in that: Calculate the data dispersion P of various timing modes i The method is the same as that for any timing mode, the method includes: Record the time difference between each time synchronization and the last time synchronization, record n ​​times in total, respectively Δt a1 to Δt an ; Record the number of device beats between each time synchronization and the last time synchronization, record n ​​times in total, respectively m a1 to m an ; Calculate the data dispersion P i , expressed as: Among them, M t Indicates the theoretical time corresponding to each beat; when a timing method is more stable, the calculated P i The closer to 0.

7. The method for adjusting the timing of a traffic signal light according to claim 5, characterized in that: The formula for calculating the actual duration of each beat under various timing modes is the same, expressed as: M j =Δt aj / m aj ,j=1,2……n Among them, M j is the actual duration of each beat calculated for the jth time, Δt aj is the time difference between the current time service and the previous time service recorded for the jth time, m aj The number of device beats between the current timing recorded for the jth time and the previous timing.

8. The method for adjusting the timing of a traffic signal light according to claim 1, characterized in that: The method further comprises: When satellite timing data packets are lost or abnormal during operation of the signal light equipment, the local timing time is compared with the recorded loss / abnormal time; If the time difference between the two is within the preset range and the central timing data packet exists, the central timing time is used and updated to the original central timing time plus the average time difference of the original satellite timing time and the original central timing time, and the maximum adjustment time allowed per second is determined according to the P value of the central timing mode and the timing deviation duration, so as to adjust the timing time; If the time difference between the two exceeds a preset range, it is determined that the device is abnormal.

9. The method for adjusting the timing of a traffic signal light according to claim 1, characterized in that: The method further comprises: When the central timing data packet is lost or abnormal during the operation of the signal light equipment, the satellite timing time is used, and the maximum adjustment time allowed per second is determined according to the P value of the satellite timing method and the timing deviation duration to adjust the timing time; If the satellite timing data packet also appears abnormal and exceeds a certain time, it is determined that the device is abnormal.

10. The method for adjusting the timing of a traffic signal light according to claim 1, characterized in that: The method further comprises: When a short power outage occurs during the operation of the signal light device, the RTC clock time is compared with the last recorded operation time of the device; If the time difference between the two is less than the preset power-off threshold, the RTC clock time is used as the timing time until power is restored, and the timing time is adjusted through the satellite timing data packet and the center timing data packet obtained in real time.

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