Method for energy-saving lighting and effectively reducing light adjustment times of expressway tunnel

Abstract

The present application relates to a kind of methods for giving consideration to energy-saving lighting of highway tunnel and effectively reducing the number of times of dimming.On the existing lighting design standard, the tunnel is fitted based on traffic flow, speed, hole brightness illumination brightness calculation formula, provide more reliable brightness calculation support for the energy-saving lighting of tunnel, and the present application combines the advantages of time sequence grading lighting and on-demand lighting according to the actual environment of tunnel, the illumination brightness level is optimized by combining the actual monitoring data of tunnel, meet the goal of tunnel on the basis of energy-saving lighting as far as possible effectively reducing the number of times of dimming, provide a solution for the tunnel to give consideration to energy-saving lighting and protection lighting system life.

Description

Technical Field

[0001] This invention relates to the field of energy-saving lighting control in highway tunnels, and particularly to a method that balances energy-saving lighting in highway tunnels with effectively reducing the number of dimming cycles. Background Technology

[0002] In recent years, with the rapid construction of expressways in my country, the number of expressway tunnels has also increased rapidly. Tunnel energy consumption costs are a major part of the operating costs of expressways, and tunnel lighting is a major source of tunnel energy consumption.

[0003] Due to the unique structure of tunnels—enclosed in the middle and connected to the external environment at both ends—they require 24-hour lighting. However, traditional time-sequential lighting patterns result in significant unnecessary energy waste, placing a heavy burden on operators. Therefore, energy-saving lighting has become a major issue that urgently needs to be addressed in highway tunnel operations.

[0004] While some scholars have proposed energy-saving lighting methods that integrate environmental information and designed control methods to adjust tunnel lighting brightness based on actual tunnel operation information, achieving some energy-saving effects, these methods neglect the actual changes in tunnel traffic and external brightness. In particular, external brightness is affected by geographical environment and weather conditions, making it relatively unstable. This leads to frequent dimming issues in brightness adjustment methods that integrate tunnel environmental information, accelerating the shortening of luminaire lifespan and increasing tunnel operation and maintenance costs. Therefore, how to balance energy-saving lighting with effectively reducing luminaire dimming frequency to protect the lighting system's lifespan has become a key research area for energy-saving tunnel lighting.

[0005] Chinese patent application number CN201310135055.9, entitled "Stepless Dimming System for LED Lighting in Highway Tunnels," utilizes the advantage of stepless dimming of LED lights. By comprehensively utilizing data on external brightness, traffic flow, and vehicle speed, it can continuously dim the LED tunnel lights in real time, obtaining different brightness levels. This effectively overcomes the flickering and uneven illuminance issues associated with hierarchical control, thus optimizing brightness control and energy efficiency throughout the tunnel. Compared to traditional time-sequential hierarchical control methods, this method offers significant energy savings, but it neglects the impact of frequent dimming on the LED lighting system.

[0006] Chinese patent application number CN201310287334.7, entitled "Tunnel Lighting Dimming Control System and Method," relates to a tunnel lighting dimming control system and method. The method first establishes a mathematical model of the brightness in each section of the tunnel and fits the brightness demand curve inside the tunnel. Using a data acquisition module, real-time vehicle speed, external brightness, and traffic flow information are collected as control parameters. The real-time lighting brightness value inside the tunnel is taken as the controlled object. After processing by the controller, the difference between the calculated setpoint and the actual value is used as the control output, continuously adjusting the output power of the lamps to achieve real-time dimming. While this method has a significant energy-saving effect, it neglects the impact of frequent dimming of the lamps due to real-time lighting, which to some extent shortens the lifespan of the lamps.

[0007] Tunnels typically employ a time-sequential lighting pattern, maintaining a certain brightness for fixed time periods. While this method suffers from significant energy waste, it is relatively simple to control. Because the lights maintain the same intensity for extended periods, adjustments are infrequent, extending the lifespan of the luminaires. Currently, on-demand lighting based on the actual tunnel environment has been proposed, offering significant energy savings. However, the actual operational conditions of tunnels vary considerably. Therefore, dimming methods designed for specific operational scenarios inevitably lead to excessively frequent brightness adjustments, which will damage the luminaires' lifespan and increase tunnel maintenance costs. Summary of the Invention

[0008] The purpose of this invention is to overcome the above-mentioned defects and provide a method that combines energy-saving lighting in highway tunnels with an effective reduction in the number of dimming cycles. This method integrates the advantages of time-sequential lighting and on-demand lighting, achieving a win-win situation for tunnels in terms of energy-saving lighting and effective reduction in the number of dimming cycles.

[0009] To achieve the above objectives, the technical solution of the present invention is: a method that combines energy-saving lighting in highway tunnels with effectively reducing the number of dimming cycles, comprising the following steps:

[0010] 1) The lighting brightness of each section of the tunnel is determined by the traffic flow N, speed V, and external brightness L. 20 (S) is used to determine this, and the calculation method is as follows;

[0011] 1) The lighting brightness of each section of the tunnel is determined by the traffic flow N, speed V, and external brightness L. 20 (S) is used to determine this, and the calculation method is as follows;

[0012] 1.1) Fitting the formula for the brightness of the entrance section: The brightness of the tunnel entrance section is determined by the brightness reduction factor k and the brightness L outside the tunnel. 20 (S) jointly determine; the reduction factor k is calculated using the following formula:

[0013]

[0014] 1.2) Calculation of entrance section brightness:

[0015] Formula for calculating entrance segment brightness:

[0016] L th1 =k×L 20 (S)

[0017] 1.3) Calculation of brightness in the transition section:

[0018] To eliminate the "black hole effect," the tunnel transition section serves to bridge the gap between bright and dark lighting. Generally, following a decreasing principle, it can be divided into three parts:

[0019] L tr1 =0.15×k×L th1 (2)

[0020] L tr2 =0.05×k×L th1 (3)

[0021] L tr3 =0.02×k×L th1 (4)

[0022] 1.4) Calculation of brightness in the middle section:

[0023] The illumination brightness of the tunnel middle section under different traffic flow and speed conditions is calculated according to formula (5):

[0024]

[0025] 1.5) Calculation of brightness at the exit section:

[0026] The brightness of the exit section is proportional to the brightness of the middle section:

[0027] L ex =5×L in (6)

[0028] 2) Combining tunnel traffic flow N, speed V, and external brightness L 20 (S) Based on historical monitoring data and the calculation formulas for lighting brightness of each tunnel section in steps 1.2)-1.5), calculate the required lighting brightness of the tunnel and denote it as L;

[0029] 3) Determine the lighting brightness mode for each section of the tunnel: Combine massive historical monitoring data to analyze the general variation law of the required lighting brightness under the lighting brightness calculation formula for each section of the tunnel, and select the lighting brightness mode corresponding to different time periods.

[0030] 4) For time periods where sequential lighting is possible, determine the corresponding fixed lighting brightness value j;

[0031] 5) For time periods requiring on-demand lighting, determine the corresponding fixed lighting brightness level value i. The specific steps are as follows:

[0032] 5.1) Set the percentage of dimming times α and the lighting waste rate β; where the percentage of dimming times α refers to the ratio of the number of dimming times at different brightness levels to the number of dimming times at the theoretical required brightness, and the lighting waste rate β refers to the percentage of dimmed brightness at different brightness levels that exceeds the theoretical required brightness; the calculation of the percentage of dimming times α and the lighting waste rate β is shown in Equations (7) and (8):

[0033]

[0034]

[0035] Among them, C i L represents the number of dimming cycles when the brightness level is i, C represents the number of dimming cycles at the theoretical required brightness, and L represents the number of dimming cycles. i L represents the dimming brightness when the brightness level is i, and L is the brightness calculated using the formula for the lighting brightness of each section of the tunnel.

[0036] 5.2) Set the range of brightness level variation X, change the brightness level value i, and assume that the theoretical required lighting brightness obtained from the traffic and external brightness information collected by the monitoring equipment and the lighting brightness calculation formula for each section of the tunnel is L. t When L t When ∈[(n-1),n×i], the actual tunnel lighting output should be L. T = n × i, where n is a positive integer;

[0037] 5.3) Statistical analysis of the percentage of dimming times α: If the current brightness calculated by the formula for the brightness of each section of the tunnel is L t The current actual lighting brightness of the tunnel is L. T And L t Satisfy L t ∈[L T -i,L T At that time, the tunnel was still constructed according to L. T The brightness value of the illumination; if L t satisfy At that time, the tunnel lighting brightness is calculated according to step 5.2), and the tunnel dimming times C are also calculated. i(t) =C i(t-1) +1;

[0038] 5.4) Combine historical monitoring data to statistically analyze the proportion of dimming times α and lighting waste rate β corresponding to different brightness level values ​​i, observe the changing patterns of the two variables, select the corresponding brightness level value i, so that the tunnel can achieve the goals of energy-saving lighting and effectively reducing the number of dimming times under the graded dimming with brightness level value i.

[0039] 6) Combining the fixed lighting brightness value j determined in step 4) and the brightness level value i determined in step 5.4), the tunnel dimming steps based on the determined brightness level value i are as follows:

[0040] 6.1) Combining real-time traffic flow N, speed V, and external brightness L 20 (S), the real-time required lighting brightness L inside the tunnel is obtained through the calculation formula of lighting brightness for each section of the tunnel. t ;

[0041] 6.2) Determine whether the current time is within a fixed brightness lighting period. If yes, proceed to step 6.4); otherwise, proceed to step 6.3.

[0042] 6.3) Determine L t If ≤j; if yes, the tunnel is currently illuminated according to the fixed lighting brightness value j; otherwise, proceed to step 6.4).

[0043] 6.4) Determine the required on-demand lighting brightness L T : Tunnel according to L T Digital lighting, This indicates rounding x down.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] 1) This invention overcomes the serious energy waste of existing time-series graded lighting modes, and fits a tunnel lighting design based on traffic flow N, speed V, and external brightness L on existing lighting design standards. 20 (S) Lighting brightness calculation formula provides relatively reliable brightness calculation support for energy-saving lighting in tunnels.

[0046] 2) This invention combines the advantages of time-sequential graded lighting and on-demand lighting based on the actual tunnel environment. It optimizes the lighting brightness level by incorporating actual monitoring data of the tunnel, thus meeting the goal of minimizing the number of dimming cycles while ensuring energy-saving lighting in the tunnel. This provides a solution for tunnels to balance energy-saving lighting with protecting the lifespan of the lighting system. Attached Figure Description

[0047] Figure 1 Flowchart for selecting lighting modes for different time periods in the tunnel.

[0048] Figure 2 Flowchart for determining the brightness value and brightness level of tunnel lighting on demand.

[0049] Figure 3 Flowchart for dimming tunnel lighting combining fixed lighting and on-demand lighting. Detailed Implementation

[0050] The technical solution of the present invention will now be described in detail with reference to the accompanying drawings.

[0051] The above and other advantages of the present invention will become more apparent from the following detailed description of preferred embodiments in conjunction with the accompanying drawings. The present invention specifically describes a method based on traffic and brightness information collected from a highway tunnel in Fujian Province; a flowchart is shown below. Figure 1 The specific steps are as follows:

[0052] 1) The calculation of lighting brightness for each section of the tunnel is based on traffic flow N, speed V, and external brightness L. 20 (S) is used to determine this, and the calculation method is as follows;

[0053] 1.1) Fitting the formula for the brightness of the entrance section. According to the "Detailed Rules for Lighting of Highway Tunnels", the brightness of the tunnel entrance section is determined by the brightness reduction factor k and the external brightness L. 20 (S) Jointly determined. The following are the reduction factors corresponding to traffic flow N≥1200, 350<N<1200, and N≥350:

[0054]

[0055] 1.2) Determination of the formula for calculating the brightness of the entrance section: L th1 =k×L 20 (S), the reduction coefficient k is determined by equation (1).

[0056] 1.3) The formula for calculating the brightness of the transition section is determined. The brightness of the tunnel transition section is divided into three parts:

[0057] L tr1 =0.15×k×L th1 (2)

[0058] L tr2 =0.05×k×L th1 (3)

[0059] L tr3 =0.02×k×L th1 (4)

[0060] 1.4) Determination of the calculation formula for the brightness of the middle section. The brightness of the tunnel middle section lighting under different traffic flow and speed conditions is calculated according to formula (5), which are the corresponding brightness calculation formulas for N≥1200, 350<N<1200, and N≥350:

[0061]

[0062] 1.5) The formula for calculating the brightness of the exit section is determined. The brightness of the exit section is proportional to the brightness of the intermediate section:

[0063] L ex =5×L in (6)

[0064] 2) Combining tunnel traffic flow N, speed V, and external brightness L 20 (S) Based on historical monitoring data and the tunnel on-demand lighting calculation formula in steps 1.2)-1.5), calculate the required lighting brightness for each section of the tunnel, denoted as L; if the current sampled traffic flow N = 1000, speed V = 100, and external brightness L 20 (S) = 3000, then the brightness value of the tunnel entrance section calculated by the formula is:

[0065] L = 94.5 cd / m 2

[0066] 3) Determine the appropriate lighting brightness mode for each section of the tunnel. Based on massive amounts of historical monitoring data, analyze the general variation pattern of the required lighting brightness for the tunnel under the brightness calculation formula, and select appropriate lighting modes for different time periods. The specific process is as follows: Figure 1 As shown.

[0067] 4) Combining extensive historical tunnel monitoring data and brightness calculation formulas, observe the distribution of required lighting brightness, and select 0:00-6:00 and 18:00-24:00 as fixed brightness lighting periods, with a corresponding fixed lighting brightness value j = 7 cd / m². 2 .

[0068] 5) Observe the distribution of required lighting brightness and determine the period from 6:00 to 18:00 as the on-demand lighting period. The specific procedure is as follows: Figure 2 As shown, the steps for determining the corresponding lighting brightness level value i are as follows:

[0069] 5.1) Given the variables α (proportion of dimming times) and β (lighting waste rate). The calculation of α (proportion of dimming times) and β (lighting waste rate) is shown in Equations (7) and (8).

[0070]

[0071]

[0072] 5.2) Set the range of brightness level variation X = [0, 20] (unit: cd / m²) 2Starting from 0, the brightness level value i (i = 1, 2, 3, ..., 20) changes every 1.0 increments. Assume the theoretical required lighting brightness L is obtained from the traffic and tunnel exterior brightness information collected by the monitoring equipment using the brightness calculation formula. t =42.3cd / m 2 When the brightness level i = 5 cd / m 2 At that time, L t ∈[40, 45], the actual tunnel lighting output should be L T =45cd / m 2 ;

[0073] 5.3) Calculate the percentage of dimming cycles α. Continue to assume that when the brightness level i = 5 cd / m²... 2 If the current luminance calculated by the lighting formula is L t =42.3cd / m 2 The current actual lighting brightness in the tunnel is L. T =45cd / m 2 The tunnel is still built according to L T =45cd / m 2 The brightness value of the illumination; if the current brightness calculated by the illumination formula is L t =47.2cd / m 2 The current actual lighting brightness in the tunnel is L. T =45cd / m 2 The tunnel lighting brightness is calculated according to step 5.2), and the tunnel dimming times C are also calculated. i(t) =C i(t-1) +1.

[0074] 5.4) Based on historical monitoring data, the percentage of dimming times α and the lighting waste rate β corresponding to different brightness levels i were statistically analyzed. Table 1 shows the changing patterns of these two variables. The table indicates that the brightness level ranges from 1 cd / m²... 2 Up to 9 cd / m 2 When the brightness level changes, the proportion of dimming cycles (α) changes significantly, decreasing by 50.91%, corresponding to a lighting waste rate (β) of 16.65%, while the brightness level is greater than 9 cd / m². 2 The latter two show opposite changes. Finally, a suitable brightness level i = 9 cd / m² is selected. 2 .

[0075] Table 1. Percentage of dimming times (α) and lighting waste rate (β) corresponding to different brightness levels.

[0076]

[0077] 6) Based on the fixed brightness value j = 7 cd / m determined in step 4), 2 And the brightness level i determined in step 5.4) is 9 cd / m.2 The tunnel dimming steps based on brightness level i are as follows, and the process is as follows: Figure 3 As shown:

[0078] 6.1) Determine the real-time required lighting brightness of the tunnel. At time T1: 12:45 on a certain day, the traffic flow N=1000, speed V=100, and external tunnel brightness L were sampled. 20 (S) = 3000, then the brightness value of the tunnel entrance section calculated by the formula is: L t =94.5cd / m 2 Traffic flow N=1000, speed V=100, and external brightness L were sampled at time T2:5:45 on a certain day. 20 If (S) = 100, then the brightness value of the tunnel entrance section calculated by the formula is: L t =3.15cd / m 2 .

[0079] 6.2) Sampling time T1 is between 6:00 and 18:00, so the tunnel adopts the on-demand lighting mode for dimming, proceed to step 6.4); Sampling time T2 is between 0:00 and 6:00, which is within the fixed lighting period, proceed to step 6.3);

[0080] 6.3) Due to L t =3.15≤j=9, the tunnel is currently operating at a fixed brightness of j=9cd / m 2 Provide lighting;

[0081] 6.4) Determine the required on-demand lighting value L T Based on the brightness level i = 9 cd / m determined in step 5.4), 2 , can be obtained Then the tunnel is according to L T =99cd / m 2 Numerical illumination ( This indicates rounding x down.

[0082] The above are preferred embodiments of the present invention. Any changes made to the technical solution of the present invention that do not exceed the scope of the technical solution of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for balancing energy-saving lighting in highway tunnels and effectively reducing the number of dimming cycles, characterized by comprising the following steps: 1) The lighting brightness of each section of the tunnel is determined by the traffic flow N, speed V, and external brightness L. 20 (S) is used to determine this, and the calculation method is as follows; 1.1) Fitting the formula for the brightness of the entrance section: The brightness of the tunnel entrance section is determined by the brightness reduction factor k and the brightness L outside the tunnel. 20 (S) jointly determine; the reduction factor k is calculated using the following formula: 1.2) Calculation of entrance section brightness: Formula for calculating entrance segment brightness: L th1 =k×L 20 (S) 1.3) Calculation of brightness in the transition section: To eliminate the "black hole effect," the tunnel transition section serves as a transition from bright to dark lighting, and is divided into three parts according to a decreasing principle: L tr1 =0.15×k×L th1 (2) L tr2 =0.05×k×L th1 (3) L tr3 =0.02×k×L th1 (4) 1.4) Calculation of brightness in the middle section: The illumination brightness of the tunnel middle section under different traffic flow and speed conditions is calculated according to formula (5): 1.5) Calculation of brightness at the exit section: The brightness of the exit section is proportional to the brightness of the middle section: L ex =5×L in (6) 2) Combining tunnel traffic flow N, speed V, and external brightness L 20 (S) Based on historical monitoring data and the calculation formulas for lighting brightness of each tunnel section in steps 1.2)-1.5), calculate the required lighting brightness of the tunnel and denote it as L; 3) Determine the lighting brightness mode for each section of the tunnel: Combine massive historical monitoring data to analyze the general variation law of the required lighting brightness under the lighting brightness calculation formula for each section of the tunnel, and select the lighting brightness mode corresponding to different time periods. 4) For time periods where sequential lighting is possible, determine the corresponding fixed lighting brightness value j; 5) For time periods requiring on-demand lighting, determine the corresponding fixed lighting brightness level value i. The specific steps are as follows: 5.1) Set the percentage of dimming times α and the lighting waste rate β; where the percentage of dimming times α refers to the ratio of the number of dimming times at different brightness levels to the number of dimming times at the theoretical required brightness, and the lighting waste rate β refers to the percentage of dimmed brightness at different brightness levels that exceeds the theoretical required brightness; the calculation of the percentage of dimming times α and the lighting waste rate β is shown in Equations (7) and (8): Among them, C i L represents the number of dimming cycles when the brightness level is i, C represents the number of dimming cycles at the theoretical required brightness, and L represents the number of dimming cycles. i L represents the dimming brightness when the brightness level is i, and L is the brightness calculated using the formula for the lighting brightness of each section of the tunnel. 5.2) Set the range of brightness level variation X, change the brightness level value i, and assume that the theoretical required lighting brightness obtained from the traffic and external brightness information collected by the monitoring equipment and the lighting brightness calculation formula for each section of the tunnel is L. t When L t When ∈[(n-1),n×i], the actual tunnel lighting output should be L. T = n × i, where n is a positive integer; 5.3) Statistical analysis of the percentage of dimming times α: If the current brightness calculated by the formula for the brightness of each section of the tunnel is L t The current actual lighting brightness of the tunnel is L. T And L t Satisfy L t ∈[L T -i,L T At that time, the tunnel was still constructed according to L. T The brightness value of the illumination; if L t satisfy At that time, the tunnel lighting brightness is calculated according to step 5.2), and the tunnel dimming times C are also calculated. i(t) =C i(t-1) +1; 5.4) Combine historical monitoring data to statistically analyze the proportion of dimming times α and lighting waste rate β corresponding to different brightness level values ​​i, observe the changing patterns of the two variables, select the corresponding brightness level value i, so that the tunnel can achieve the goals of energy-saving lighting and effectively reducing the number of dimming times under the graded dimming with brightness level value i. 6) Combining the fixed lighting brightness value j determined in step 4) and the brightness level value i determined in step 5.4), the tunnel dimming steps based on the determined brightness level value i are as follows: 6.1) Combining real-time traffic flow N, speed V, and external brightness L 20 (S), obtained from the formula for calculating the lighting brightness of each section of the tunnel. Real-time lighting requirements L within the tunnel t ; 6.2) Determine whether the current time is within a fixed brightness lighting period. If yes, proceed to step 6.4); otherwise, proceed to step 6.

3. 6.3) Determine L t If ≤j; if yes, the tunnel is currently illuminated according to the fixed lighting brightness value j; otherwise, proceed to step 6.4). 6.4) Determine the required on-demand lighting brightness L T : Tunnel according to L T Digital lighting, This indicates rounding x down.

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