A timing adjustment method for traffic signal lights

Abstract

The application discloses a timing time adjustment method of a traffic signal lamp, and relates to the field of intelligent traffic, which comprises the following steps: a signal lamp device acquires satellite timing data packets and central timing data packets in real time during operation, wherein the satellite timing data packets and the central timing data packets contain timing times provided by various timing modes; the stability values P of the various timing modes are calculated 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 time length allowed to be adjusted per second under the timing mode is determined according to the corresponding P value and the timing deviation time length; the device adjusts the timing time according to the maximum time length allowed to be adjusted per second, and calculates the maximum time length allowed to be adjusted per second until the timing deviation is eliminated. When the intelligent signal lamp device uses wireless or bus communication, the precision timing between the devices can be realized, and the risk caused by the time asynchronization of the signal control device is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of intelligent transportation, in particular to a time adjustment method for traffic signal lights. BACKGROUND

[0002] The current traffic products, especially the signal system related products, do not have a unified standard for the management and application of time data. Most of them use simple single time method, such as single satellite (GPS, Beidou) time or central virtual signal machine time (referred to as central time). Or priority arrangement, such as central time priority over satellite time. When both time data exist, select according to priority. This kind of rough time correction method can basically meet the use demand of traditional signal machine. Since a single intersection is controlled by a signal machine, and the signal light uses 220V control and cut-off mode, the signal machine will not affect the single intersection release scheme execution, and will not cause serious traffic safety hidden trouble problem such as green conflict. But with the development of signal system, especially the development of intelligent signal lights connected by wireless or bus, the original signal system architecture is broken, and the demand for time accuracy has also changed.

[0003] After introducing the concept of wireless intelligent signal light, the intersection level signal machine will be removed and replaced by independent networked intelligent signal light. At this time, the time correction stability is improved from seconds to tens of milliseconds. Since the red and green lights of a intersection need to be corrected respectively, and a set of release scheme needs to be run simultaneously between them, the switching of each light needs to be within the error of tens of milliseconds, otherwise it will cause short time green conflict and other situations, which will cause certain hidden troubles for illegal snapshot judgment and actual driving safety. The central time data packet used for time correction 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. Especially for wireless network, it is more sensitive to external interference, and the overall delay will increase greatly. Satellite time will cause weak signal problems due to weather, location and other problems, so that the receiving device will lose time data packet for a long time, and then cause time interruption problem.

[0004] After the intelligent upgrade of signal light, more functions can be integrated to make the control and management of signal more intelligent. But at the same time, through wireless and bus communication, data delay and error will inevitably occur, which will seriously affect the signal control. But if the correctness of each device time can be guaranteed, each signal light can work in the state of disconnection with the signal control end for a long time, which can well solve the above problems. SUMMARY

[0005] The present inventors propose a time adjustment method for traffic signal lamps to solve the above problems and technical needs, so that each device can achieve a timing accuracy of 10 milliseconds when the intelligent signal lamp device uses wireless or bus communication, and the method can deal with timing exceptions caused by environment, communication, and hardware failure, and minimize the risk of signal control devices caused by different time synchronization.

[0006] For intelligent signal lamps controlled using wireless form, timing will be the core parameter for stable operation. Since each group of signal lamps connected through wireless form, timing data transmission is easily affected by distance, external interference, and device data processing speed, resulting in packet loss and unavoidable transmission delay. These are technical actual problems that cannot be changed, which leads to the fact that signal lamps in wireless form cannot use real-time control mode for light color switching. The switching of all signals of intelligent signal lamps is controlled by preset time, not real-time control instruction. The switching control by preset time requires timing between devices to reach a precision of 10 milliseconds, and time jump problem is not allowed, otherwise it will cause confusion of red and green light release signals, and even cause serious traffic accidents. However, it can avoid the problem of not timely switching caused by signal loss and network delay, which leads to green conflict and release confusion.

[0007] Satellite timing and part of RTC clock chip use second-level pulse time correction. The intelligent signal lamp device performs millisecond-level timing through internal beat. At this time, the sampling point per second may be affected by system operation, and the sampling time will have a certain deviation. Because of the deviation of the sampling point or reading point, it is easy to cause 1 second error between two sampling time points. 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, there will be a 1 second error between multiple devices at the same intersection. When the second-level error is applied to the light color switching of the independent intelligent signal lamp application scenario at the intersection, it will cause serious safety hazards to traffic signal control.

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

[0009] A timing time adjustment method for traffic signal lamps, comprising the following steps:

[0010] The signal lamp device acquires satellite timing data packet and center timing data packet in real time during operation, which contains timing time provided by various timing methods;

[0011] The stability value of each timing method is calculated respectively P ;

[0012] When the timing time provided by the selected timing method of the device has timing deviation from the local timing time, the correspondingP The value and the time length of the time service deviation determine the maximum time length allowed to adjust per second under the time service mode;

[0013] The device adjusts the time service time according to the maximum time length allowed to adjust per second, and calculates the maximum time length allowed to adjust per second next time until the time service deviation is eliminated.

[0014] Further technical solutions are that the stability value of each time service mode is calculated P The method is the same for any time service mode, and the method includes:

[0015] The time difference between each time service and the last time service is recorded, and the recording is performed n times, respectively Δ t a1 to Δ t an ;

[0016] The device beat timing between each time service and the last time service is calculated, and the calculation is performed n times, respectively Δ t b1 to Δ t bn ;

[0017] The stability value is calculated P , which is expressed as:

[0018]

[0019] When a certain time service mode is more stable, the calculated P value is closer to 0;

[0020] The device beat timing is defined as the product of the beat number counted by the device in the time interval between two time services and the actual time length corresponding to each beat.

[0021] Further technical solutions are that the maximum time length allowed to adjust per second is determined according to the corresponding P value and the time length of the time service deviation, including:

[0022] The maximum time length allowed to adjust per second is denoted as t pmax , and the calculation formula is:

[0023]

[0024] , wherein t a is the time service time provided by the device selected time service mode, t b is the local timing time, t c is the time length allowed to adjust per second basic value, k is a preset constant;

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

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

[0027] Set P The value is less than 1, corresponding to low P Value case, at this time the time data is relatively stable, otherwise corresponding to high P Value case, at this time the time data is unstable;

[0028] When the time deviation time length is less than 1s in the high P Value case, the calculated t pmax Is small, to realize the time adjustment; when the time deviation time length is not less than 1s in the high P Value case, the calculated t pmax Is amplified, to realize the time adjustment;

[0029] When the time deviation time length is less than 1s in the low P Value case, the calculated t pmax Is amplified, to realize the time adjustment; when the time deviation time length is not less than 1s in the low P Value case, the calculated t pmax Is small, to realize the time adjustment.

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

[0031] The signal light device at least acquires satellite time data packet and center time data packet in real time during the boot process, which contains time provided by various time modes;

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

[0033] The data dispersion of various time modes is calculated respectively P i ;

[0034] When the data dispersion of various time modes isP i When the threshold is not exceeded, the actual duration of each beat corresponding to each time service mode is calculated, which is used to calculate the device beat timing between each time service and the last time service in each time service mode;

[0035] Wherein, the device counts according to the reference clock input from outside, and when the clock number accumulated for a single beat is full, it 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 time services and the actual duration of each beat.

[0036] A further technical solution is to calculate the data dispersion of each time service mode P i The method is the same for any time service mode, and the method includes:

[0037] Record the time difference between each time service and the last time service, a total of n times, respectively Δ t a1 to Δ t an ;

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

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

[0040]

[0041] Wherein, M t represents the theoretical time corresponding to each beat; when a time service mode is more stable, the calculated P i is closer to 0.

[0042] A further technical solution is that the formula for calculating the actual duration of each beat in each time service mode is the same, which is expressed as:

[0043] M j =Δ t aj / m aj , j =1,2…… n

[0044] Wherein, M j is thej the actual time length corresponding to each beat of the secondary calculation, Δ t aj the current time of the first j the time difference between the current time of the second record and the last time of the time service, m aj the number of device beats between the current time of the first j the number of device beats between the current time of the second record and the last time of the time service.

[0045] A further technical solution of the present application is that the method further comprises:

[0046] When the satellite time service data packet is lost or abnormal during the operation of the signal lamp device, the local timing time is compared with the recorded lost / abnormal time;

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

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

[0049] A further technical solution of the present application is that the method further comprises:

[0050] When the central time service data packet is lost or abnormal during the operation of the signal lamp device, the satellite time service time is adopted, and the maximum time length allowed for adjustment per second is determined according to the P value and the time service deviation length to adjust the time service time;

[0051] If the satellite time service data packet is also abnormal and exceeds a certain time, the device is determined to be abnormal.

[0052] A further technical solution of the present application is that the method further comprises:

[0053] When the signal lamp device is short-circuited during operation, the RTC clock time is compared with the recorded last running time of the local machine;

[0054] If the time difference between the two is less than the preset power-off threshold, the RTC clock time is adopted as the time service time, and after the power is restored, the time service time is adjusted by real-time acquisition of the satellite time service data packet and the central time service data packet.

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

[0056] The method does not need to increase additional equipment, only uses satellite time service, center time service data and RTC clock time, through the designed time service time adjustment method, maximally guarantees the accuracy of time service and the stable operation of signal control system, avoids the occurrence of time service jump, abnormal switching and the processing method of the fault of packet loss or abnormality of each part of time service related hardware, carries out system design, and improves the applicability of the method. After the method is applied to the wireless intelligent signal lamp and bus signal machine, the landing ability of the products is greatly improved in an economical way, and technical support is provided for the future development of traffic signal control. BRIEF DESCRIPTION OF DRAWINGS

[0057] Figure 1 Figure 1 is a device structure diagram of the wireless intelligent signal lamp provided by the present application.

[0058] Figure 2 Figure 4 is a time service time adjustment method flow chart of the traffic signal lamp provided by the present application.

[0059] Figure 3 Figure 5 is a time service flow chart of the start-up process provided by the present application. DETAILED DESCRIPTION

[0060] The specific embodiments of the present application will be further described in combination with the drawings.

[0061] The present embodiment describes a time service time adjustment method of a traffic signal lamp by solving the time service problem of a wireless intelligent signal lamp, wherein the time service sources of the wireless intelligent signal lamp include center time service (wireless form), satellite time service (GPS or Beidou), and clock chip (RTC) provided by the device. The core content of the method is to obtain the error between each data value and the actual timing through calculation, and through an adjustment method, the adjustment of unstable time service is well inhibited, and the adjustment speed of stable time service is improved. The method realizes the stability of intersection level and regional level time service, and the stable execution of traffic release scheme, and when part of the time service deviates or is lost, the method also provides a time service switching method to ensure that the device time does not jump and realizes stable transition. The method is not only suitable for wireless intelligent signal lamps, but also suitable for non-real-time control signal machines (bus control) and traditional real-time control signal machines.

[0062] As Figure 1As shown, the intelligent traffic signal system is characterized by traffic light equipment communicating with a central server via 5G. There are no physical traffic lights at intersections; instead, the lights are virtualized and integrated into the central system. Its advantages include eliminating the need for complex wiring at intersections and removing traffic signal controllers, significantly reducing construction costs. Furthermore, the 5G connection allows for the transmission of more data. Through the intelligent traffic light controller, the central system can directly monitor various parameters of the traffic lights, including but not limited to ambient brightness, power consumption, device posture, and internal environmental conditions. It can even provide signal transmission links for peripheral devices such as traffic flow radar and surveillance cameras, providing a platform for the intelligentization of traffic lights. To ensure coordinated control of traffic lights at intersections and within areas, time synchronization management is required using the following method, which provides the technical foundation for the implementation of the wireless traffic light + virtual traffic light solution.

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

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

[0065] Step 4: Calculate the stability values ​​for each time synchronization method. P .

[0066] Calculate the stability values ​​of various time synchronization methods. P The method is the same. For any time synchronization method, this step specifically includes: recording the time synchronization data (satellite time synchronization time, center time synchronization time) for each channel; recording the time difference between each time synchronization and the previous time synchronization using a rolling recording method, recording n times, denoted as Δ. t a1 To Δ t an Calculate the device cycle time between each time synchronization and the previous time synchronization, calculate n times, and assign Δ to each cycle. t b1 To Δ t bn Equipment cycle time can be understood as the equipment counting based on an externally input reference clock. When the required number of clock cycles for a single cycle is accumulated, it is counted as one cycle. The equipment cycle time is calculated by multiplying the number of cycles counted by the equipment between two time intervals by the actual duration of each cycle. The actual duration of each cycle can be calculated during equipment startup, which will be explained in detail later. It is important to note that due to the accuracy deviation of the equipment's reference clock under different environments, the cycle time obtained by the equipment based on the reference clock is not necessarily the actual natural time.

[0067] The stability value is calculated by the above data P , which is expressed as:

[0068]

[0069] When a certain time service is more stable, the calculated P value is closer to 0; when the P value exceeds a preset threshold, the device will determine that the corresponding time service is unstable, and the time service data is unusable.

[0070] Step 6: When the time service time provided by the time service selected by the device has a time service deviation from the local time, determine the maximum time length allowed for adjustment per second in the time service according to the corresponding P value and the time service deviation length, denoted as t pmax , the calculation formula is:

[0071]

[0072] , wherein: t a is the time service time provided by the time service selected by the device; t b is the local time, which can be obtained by counting the actual beats; t c is the per-second adjustment time length base value, which is usually a fixed constant; k is a preset constant, with a value of 10-100.

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

[0074] According to the size of the time service deviation length, the corresponding t pmax is calculated, then when the device adjusts the time service time according to the maximum time length allowed for adjustment per second, it is divided into time service time suppression adjustment and time service time rapid adjustment according to the size of the P value, denoted as P value is less than 1, corresponding to a low P value case, in which the time service data is relatively stable, otherwise, corresponding to a high P value case, in which the time service data is unstable, and different cases are described as follows:

[0075] When the time service deviation length is less than 1s in the high P value case, P value is greater, the calculated t pmaxSmall, at this time, the smaller timing deviation adjustment requirements due to the timing mode instability caused by normal fluctuations, no need to quickly adjust, so the smaller t pmax To achieve timing time suppression adjustment. When the high P value case timing deviation duration is not less than 1s, P The greater the value, the smaller the calculated t pmax Amplification, at this time, for the emergence of larger timing deviation adjustment needs to be adjusted through a larger t pmax To achieve timing time fast adjustment, so as to ensure that the device from unstable to stable fast transition, so that the timing deviation is quickly adjusted to complete.

[0076] When the low P value case timing deviation duration is less than 1s, P The smaller the value, the greater the calculated t pmax Amplification, at this time, the timing time is not prone to abnormal fluctuations, but the timing still exists cumulative error adjustment, belongs to the inevitable adjustment, therefore, through a larger t pmax To achieve timing time fast adjustment, so that the device time can be quickly fine-tuned to ensure the time synchronization between devices. When the low P value case timing deviation duration is not less than 1s, P The smaller the value, the greater the calculated t pmax Small, at this time, the timing time running stable, occasional larger timing deviation adjustment requirements, may be caused by abnormalities, so the smaller t pmax To achieve timing time suppression adjustment, at this time, the calculated t pmax , will be less than the high P value when a larger fluctuation corresponding to the t pmax calculated value.

[0077] Actual in the timing time adjustment, such as the timing time and the local time exists 20ms error, t pmax 15ms after calculation, the current second most allow adjustment 15ms difference time, adjustment error value is 5ms state; the next second continue the above calculation process, such as the next calculation after the maximum allowed adjustment time is 10ms, but the current error value 5ms less than 10ms, then this according to 5ms adjustment.

[0078] Since various time service modes will not have a large jump when working normally, the jump is generally caused by network delay, communication anomaly, but also cannot be ruled out cumulative error adjustment, so in this embodiment, when the time service time is inconsistent with the device time, the time needs to be adjusted, or in the case of sudden time correction, according to the time service deviation, a P value and t pmax calculation method is used to adjust through multiple adjustments. On the one hand, the time is switched from second-level adjustment to millisecond-level adjustment during the adjustment process, and through multiple fine adjustments, the problem of release scheme disorder caused by time jump is avoided, and the synchronization of the red and green lights between devices is ensured. On the other hand, some sudden deviations may be caused by various time service data transmission delays, data output stalls, and data processing anomalies. Such deviations generally do not have continuity, or even if they are continuous, they can be inhibited and filtered through a gradual adjustment method.

[0079] For time service switching problems, the characteristics of various time service sources are analyzed and selected. The characteristics of satellite time service are high accuracy but poor stability. The characteristics of central time service are that it connects all devices and is easy to synchronize, but network delay will lead to relatively poor accuracy and general stability. The problem of RTC clock chip is that the signal control device is generally in an outdoor state, and the outdoor temperature has a certain impact on the crystal oscillator, and its error will be accumulated and reflected in the on-off of the signal light, but its signal is relatively stable. Based on this, a set of time service switching method is designed, which is divided into boot process time service selection and running process time service selection. Then, the time service time adjustment method of the traffic signal lamp further includes the following boot process time service selection content before step 2:

[0080] Please refer to Figure 3 , first, the signal lamp device acquires satellite time service data packet, central time service data packet and RTC clock chip time service data packet in the boot process. That is, the device is powered on, waits for the satellite time service receiving module to start, and requests central time service data and RTC clock chip time service data. The device receives various time service data packets, which include the time service time provided by various time service modes.

[0081] Second, when the deviation between the central time service time and the satellite time service time is less than the preset deviation value, the device uses the time division second of the satellite time service time and uses the pulse signal for millisecond-level timing to improve the time consistency between devices through the satellite pulse signal. At this time, the device records the satellite time service, central time service, and RTC clock chip time service data, and calculates the data dispersion P i of various time service modes P iThe method is the same as the above, for any time service mode, specifically including: recording the time difference between each time service and the last time service, a total of n times, respectively Δ t a1 to Δ t an Recording the number of device beats between each time service and the last time service, a total of n times, respectively m a1 to m an Calculating the data dispersion P i , expressed as:

[0082]

[0083] Wherein, M t represents the theoretical time corresponding to each beat. When the P i ≤1, it indicates that the time service mode is stable, and the subsequent acquired time service data or the recorded time service data can be used to calculate the relationship between the device beat number and the time service data.

[0084] Optionally, the preset deviation value is recommended to be set to ±200ms, and the value can also be set separately, which is confirmed according to the network average delay. The larger the delay, the larger the preset deviation value.

[0085] Finally, when the P i of each type of time service mode does not exceed the set threshold (such as 1), the actual length of each beat corresponding to each type of time service mode is calculated, and the calculation formula of the actual length of each beat corresponding to each type of time service mode is the same, expressed as:

[0086] M j =Δ t aj / m aj , j =1,2…… n

[0087] Wherein, M j is the actual length of each beat corresponding to the j time calculation, Δ t aj is the time difference between the current time service and the last time service recorded for the j time, m aj is the number of device beats between the current time service and the last time service recorded for the j time.

[0088] The values of satellite time, central time, RTC clock time are calculated respectively, which are used to calculate the device beat time Δ M t bj M j m bj , where m bj is the beat number of the device statistics of the previous and next time interval, and Δ j b is calculated separately for each time. t pmax

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

[0090] A timing time adjustment method of a traffic signal light, after step 8, further includes the following running process of timing selection content:

[0091] When the device is normally running, the device timing is based on the satellite timing time, and the values of the satellite timing and the central timing are calculated continuously P t pmax ; and the average time difference between the satellite timing time and the central timing time is calculated t u , and these data are written into the RTC clock at a certain interval. Under the condition that the timing data of each type is not lost, the device will adjust the timing time through the method of steps 2-8. When the following conditions occur, the following processing will be performed:

[0092] ① When the signal light device loses or abnormally loses the satellite timing data packet during the running process ( P i >1), compare the local timing time with the recorded lost / abnormal time. If the time difference between the two is within the preset range, i.e. the satellite lost time is shorter, and there is a central timing data packet, then the central timing time is used and updated to the original central timing time t a plus the average time difference​​​​​t u and according to the time difference between the two P and the time difference between the two to determine the maximum time allowed for adjustment per second, so as to adjust the timing time according to steps 6 and 8. If the time difference between the two exceeds the preset range, i.e. the satellite loses for a long time, it is determined that the device is abnormal.

[0093] 2) When the signal light device loses the central timing data packet or is abnormal during operation P i 1), the satellite timing time is used, and the timing is stabilized. According to the time difference between the two P and the time difference between the two to determine the maximum time allowed for adjustment per second, so as to adjust the timing time according to steps 6 and 8. If the satellite timing data packet is also abnormal P i 1) and exceeds a certain time, it is determined that the device is abnormal.

[0094] 3) When the signal light device loses power for a short time during operation, the device starts to read the RTC clock signal, compares the RTC clock time with the recorded last running time of the local machine. 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 the starting position of the second level is confirmed through multiple readings, and this time is used as the transition. After the power is restored, the satellite timing data packet and the central timing data packet are obtained in real time to re-execute steps 2~8 to adjust the timing time. Through this method, after the short power loss, the device timing time can be quickly adjusted and recovered under the condition of ensuring the operation accuracy.

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

Claims

1. A method for adjusting the timing of a traffic signal, characterized in that The method comprises: The signal lamp device acquires satellite timing data packet and central timing data packet in real time during operation, which contains timing time provided by various timing modes; The stability value of each type of time service is calculated respectively P ; When the time-provided by the time-providing mode selected by the device has time-providing deviation from the local time, the maximum time length allowed to be adjusted per second in the time-providing mode is determined according to the corresponding P value and the time-providing deviation length. The device adjusts timing time according to the maximum length of the allowed adjustment per second, and calculates the maximum length of the allowed adjustment per second until the timing deviation is eliminated; wherein the stability value of each type of time service is calculated P The method is the same for each type of time service, and for any type of time service, the method comprises: Record the time difference between each time service and the last time service, record n times, respectively Δ t a1 to Δ t an ; Calculate the device tick timing between each time service and the last time service, calculate n times, respectively Δ t b1 to Δ t bn ; computing a stability measure P is expressed as: wherein the value calculated is closer to 0 when a certain time service is more stable P value is closer to 0. The device beat timing is defined as the product of the number of beats counted by the device and the actual length of each beat; The method comprises the following steps: P The method further comprises the following steps: determining the maximum time length of adjustment allowed per second in the time service mode according to the corresponding The maximum time length of the allowed adjustment per second is denoted as t pmax The calculation formula is: wherein, t a a time of time service provided for the time service mode selected by the device, t b a local time, t c a base value of the allowed adjustment duration per second, k a preset constant; According to the time service deviation length size selection corresponding t pmax The formula, when the device adjusts the time service time according to the maximum length of the allowed adjustment per second, according to P The value size is divided into time service time suppression adjustment and time service time rapid adjustment.

2. The traffic signal time adjustment method of claim 1, wherein When the device adjusts the time of the time service according to the maximum length of the allowed adjustment per second, the adjustment is performed according to P The value is divided into time service adjustment inhibition and time service fast adjustment according to the size, comprising: Set P values less than 1 correspond to low P value cases, where the time service data is relatively stable, otherwise they correspond to high P value cases, where the time service data is unstable; When at the high P When the timing deviation is less than 1 second under the given conditions, the calculated value is... t pmax The value is too small to achieve the time synchronization suppression adjustment; when the value is too high... P When the timing deviation is not less than 1 second under the given conditions, the calculated value is... t pmax It is magnified to enable rapid adjustment of the time synchronization; When the time service deviation duration is less than 1s in the low P value case, the calculated t pmax is amplified to realize the fast adjustment of the time service time; when the time service deviation duration is not less than 1s in the low P value case, the calculated t pmax is small to realize the inhibition adjustment of the time service time.

3. The traffic signal time adjustment method of claim 1, wherein The method further comprises: The signal lamp device acquires satellite timing data packet and central timing data packet in real time during operation, which contains timing time provided by various timing modes; When the deviation between the central timing time and the satellite timing time is less than the preset deviation value, the device adopts the satellite timing time; Calculate the data dispersion of each type of time service respectively P i ; When various time service modes P i When the threshold is not exceeded, the actual time length corresponding to each beat under each time service mode is calculated respectively, which is used to calculate the device beat timing between each time service and the last time service under each time service mode. The device counts according to the reference clock input from outside, and records a beat when the accumulated clock number required for a single beat is reached; the device beat timing is defined as the product of the number of beats counted by the device and the actual length of each beat.

4. The traffic signal time adjustment method of claim 3, wherein Computing data dispersion for various time service methods P i The method is the same for any time service method, and comprises, for any time service method, Record the time difference between each time service and the last time service, a total of n times, respectively Δ t a1 to Δ t an ; Record the device ticks between each time service and the last time service, a total of n times, respectively m a1 to m an ; Computing data dispersion P i is represented as: wherein, M t represents the theoretical time corresponding to each beat; the more stable a certain time service is, the closer the calculated P i is to 0.

5. The traffic signal time adjustment method of claim 3, wherein The formula for calculating the actual length of each beat corresponding to each timing mode is the same, which is expressed as: M j = Δ t aj / m aj , j =1,2… n wherein, M j is the first j calculated actual duration of each beat, Δ t aj is the first j recorded time difference between the current time and the last time, m aj is the first j recorded number of device beats between the current time and the last time.

6. The traffic signal time adjustment method of claim 1, wherein The method further comprises: When the signal lamp device loses or abnormally acquires the satellite timing data packet during operation, the local timing time is compared with the recorded lost / abnormal time; If the time difference is within the preset range and the central time service data packet exists, the central time service time is adopted and updated to the original central time service time plus the average time difference of the original satellite time service time and the original central time service time, and the maximum time length of adjustment per second is determined according to the value of the central time service mode and the time service deviation length, so as to adjust the time service time. P If the time difference is within the preset range and the central time service data packet exists, the central time service time is adopted and updated to the original central time service time plus the average time difference of the original satellite time service time and the original central time service time, and the maximum time length of adjustment per second is determined according to the value of the central time service mode and the time service deviation length, so as to adjust the time service time If the time difference between the two exceeds the preset range, the device is determined to be abnormal.

7. The traffic signal time adjustment method of claim 1, wherein The method further comprises: When the center time service data packet is lost or abnormal during the operation of the signal lamp device, the satellite time service time is adopted, and the maximum time length of the allowed adjustment per second is determined according to the satellite time service mode value and the time service deviation time length, so as to adjust the time service time. P When the center time service data packet is lost or abnormal during the operation of the signal lamp device, the satellite time service time is adopted, and the maximum time length of the allowed adjustment per second is determined according to the satellite time service mode value and the time service deviation time length, so as to adjust the time service time. If the satellite timing data packet also appears abnormal and exceeds a certain time, the device is determined to be abnormal.

8. The traffic signal time adjustment method of claim 1, wherein, The method further comprises: When the signal lamp device is powered off for a short time during operation, the RTC clock time is compared with the recorded last running time of the local device; If the time difference between the two is less than the preset power-off threshold, the RTC clock time is adopted as the timing time until the power is restored, and the timing time is adjusted through the real-time acquisition of the satellite timing data packet and the central timing data packet.

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