Technical analysis of tunnel lighting engineering

Technical Analysis of Tunnel Lighting Engineering in Western Exploration Engineering Chen Yigang (China Railway 13th Bureau Group Co., Ltd., Changchun 130031, China) With the full development of highway construction in China, the long road tunnel is the main way to solve highway traffic in mountainous hills, in many The area is being built. Expressway tunnels should have a safe and good traffic operation environment. Tunnel electrical and mechanical engineering is a necessary means to achieve this goal. The lighting system is an important part of the tunnel electromechanical engineering, which plays a vital role in ensuring the safety of traffic operations within the tunnel and beautifying the traffic operation environment within the tunnel. Due to the faster speed of the expressway, generally >100km/h requires very high light intensity and its variation. The tunnel environment is affected by automobile exhaust, dust, moisture and chemical corrosion. The operating environment of electrical equipment is very harsh. How to ensure the safe and stable operation of electrical equipment and ensure safe driving is of great significance. In recent years, traffic accidents at highways and highways at home and abroad have occurred from time to time, causing major loss of life and property and social impact is extremely bad. Enough to attract a high degree of attention. At the same time, the tunnel lighting system represents the appearance of the tunnel electrical and mechanical engineering, and its quality directly affects the tunnel environment. It can be said that the lighting system is the key to the success of tunnel electromechanical engineering. In addition, the lighting system does not exist in isolation, it is most restricted by civil engineering, and is inseparable from other systems of electromechanical engineering. As a whole, tunnel electrical and mechanical engineering, including lighting system, ventilation system, power supply system, fire protection system, traffic monitoring system, CCTV systems, communication systems, fire alarm systems and central control systems cover a wide range of disciplines including power, electrical, electronics, computers, communications, machinery, and transportation.

The author has participated in the construction of electromechanical engineering of many highway tunnels in Guangdong Province and has been engaged in first-line engineering and technical work. Combine personal experience and related technical materials to talk about the design and construction technology of tunnel electrical and mechanical engineering lighting system.

1 Power supply technology analysis 1.1 Lighting load 1.1.1 Load level Tunnel lighting system can be divided into basic lighting, reinforced lighting, emergency lighting, tunnel lighting and cross-channel lighting according to different functions. Emergency lighting and basic lighting are primary load. The other is a secondary load.

1.1.2 Load characteristics Tunnel lighting uses tunnel-specific lamps, which have various characteristics to adapt to the tunnel environment. The light source uses high-pressure sodium lamps, and the auxiliary appliances have triggers, ballasts and compensation capacitors. The tunnel luminaire is durable structure (up to GB7000 requirements) and waterproof and dustproof (up to IP65 in GB9001). Its optical system meets the required height standard in the tunnel. The reflector adopts low glare light distribution suitable for tunnel illumination. The electrical characteristics have a compensation power of 0.9. The starting current should be less than the working current. The starting voltage is 220V*10%. The recovery starting time <60s allows the instantaneous voltage drop to be Tianjin Schrader, Tianjin Thorne, Shanghai GE, etc.

1.2 Tunnel lighting power supply principle In order to maintain the life of the light source, the terminal voltage of the high-pressure sodium lamp should be at the rated voltage to reduce the impact of shock voltage fluctuations and flicker on the lighting. Tunnel lighting special transformer should be used, and the load rate can be selected at 70% of the rated capacity. ~80%. When the transformer is supplied with an impact load such as a tunnel fan, it should be powered by a dedicated line.

The low-voltage power distribution mode adopts a tree-type and radial hybrid power distribution mode, and the low-voltage power distribution system adopts a three-phase four-wire system. The voltage level is 220V/380V, and the grounding system uses the TN*S system.

The transformer wiring group should adopt D9Yn11 junction line, which is beneficial to reduce loss and suppress harmonics.

The low-voltage distribution cable uses a four-core flame-retardant and fire-resistant cable.

For tunnel luminaires with a starting current greater than the operating current, the switch and cable cross section should be compared to avoid protection failure or low pressure drop.

Capacitor is used for dispersion compensation or centralized compensation. Emergency power supply and working power supply adopt reliable measures to prevent parallel operation. The emergency power supply should be powered by a battery DC inverter or an independent self-starting diesel generator set. The centralized setting can be an on-line uninterruptible power supply (UPS), and the decentralized setting can be a self-rechargeable emergency light.

1.3 According to the requirements of the first-level load power supply, the power supply adopts two dedicated 10kV power supplies, which are operated in sections and spared each other. The standby device is set up, and the 0.4kV fast self-starting diesel generator set is used as the backup power supply. The emergency lighting power supply is powered by the UPS device (see 1.4 The number of transformer substations in a substation should be determined according to its length. Two substations should be installed in a tunnel with a length of > 1km.

The setting of the tunnel substation follows the following principles: reducing the voltage drop of the low-voltage line; the tunnel substation is generally placed at both ends of the tunnel, and there are two ways: independent and attached. Stand-alone applications are more widely used. Due to the longitudinal jet mechanical ventilation and natural ventilation, the tunnel exit is seriously polluted. Therefore, the specific location should be at the two ends of the tunnel. The outside of the light source life tunnel lighting charm shin mine belt area eight. With a large use space and good ventilation, it is suitable for the stable operation of electrical equipment and has a duty. At the same time, the tunnel monitoring center can be built together for maintenance and management. In addition, the tunnel end is generally located at the foot of the mountain. The terrain is more complicated. The location of the substation should be considered when designing the main body of the tunnel. The location of the tunnel junction or the extremely steep tunnel junction should be shifted or Select the affiliate. The substation substation is located in the special equipment cave room between the two holes at both ends of the tunnel, and is constructed synchronously with the main body of the tunnel. The cavern should be connected to the left and right holes. It has enough space to facilitate ventilation and installation and operation of the equipment. This type of substation equipment has a poor operating environment. If the humidity is severe, special ventilation equipment should be installed in the equipment cave. The wind direction should be blown from the inlet end to the outlet end, suitable for unattended and remote control.

1.5 Distribution equipment High-voltage power distribution system is a dual power supply line, single busbar segmentation wiring form, two power supply at the same time during normal operation, the mother cabinet is disconnected, when the external line is out of power, the incoming line cabinet is opened and the bus is connected When the cabinet is closed, when the incoming line resumes power supply, it will resume normal operation. The high-voltage power distribution cabinet is equipped with a microcomputer power relay protection intelligent module that can be automatically controlled locally or remotely.

The low-voltage power distribution system is a three-power incoming single-bus line segmented wiring. In normal operation, the two main power supplies are powered at the same time. The main bus is disconnected, and the two power supplies are mutually standby and automatically put into operation. When the two main power sources are de-energized, the standby power supply and the diesel generator set are automatically activated, and the second type of load needs to be reduced. The incoming power supply should have three levels of protection: instantaneous, short delay, and long delay. The outgoing power supply should have short-circuit and over-current protection.

If the emergency lighting power supply system uses UPS power supply, the link is more complicated. The UPS power supply has two modes of operation: bypass and online. Manual switching is required, and the online operation mode can automatically switch the battery to the inverter AC output power supply when the power is lost. In emergency lighting power supply, the UPS current should be an independent backup power supply. In the online working mode, another dedicated main supply emergency lighting power supply is set up. The power supply and the UPS power supply are two-way power supply for emergency lighting, and the two can be switched with each other. When the main power supply is de-energized, the power is automatically switched to the UPS power supply. When the main power supply is restored, the main power supply is automatically switched to the UPS power supply. In the standby state, the operation mode of the two-way power supply is one master and one standby. The reason why the UPS power supply is not put into the online main supply operation is because the UPS is switched under emergency conditions. It can reduce the occurrence of faults, high-power UPS maintenance, UPS power outlet switch, the choice should be reasonable, as far as possible to reduce the UPS power supply overload operation.

The high-voltage power distribution cabinet selects the hand-cart type, the switch is a vacuum circuit breaker, and the low-voltage power distribution cabinet selects a drawer type, which is convenient for replacement and maintenance.

1.6 Distribution Cable Selection and Laying Cable Selection Select the section according to the temperature rise and pass the voltage loss check. If the cross section needs to be enlarged, the voltage drop at the power supply terminal is required to be <5%. The tunnel lighting load capacity is small, but the distance is long, so the voltage loss is more important than the selection of the cable cross section. When the length of the tunnel is between 1~3km, the cable cross section is generally below 50mm2, and the minimum distribution cable cross section is 4mm2. The emergency lighting cable uses fire-resistant cable. The other lighting circuits use flame-retardant cable. The fire-resistant and flame-retardant cable is used because the tunnel is prevented. Once a fire occurs, it will cause great harm to human life. There are two reasons for the fire caused by cables and wires: external fire source and self-fire. In the event of a fire in ordinary PVC cable, the released toxic gas can cause suffocation within 2 minutes. Moreover, the tunnel has a relatively closed environment and a long escape distance. Therefore, the distribution cables in the tunnel are made of flame-retardant and fire-resistant cables.

The cable channel is the only way to implement the cable. The tunnel cable channel is generally implemented with the main civil engineering of the tunnel. The design and construction of the cable directly affects the construction quality of the cable, and even the construction cannot be carried out, resulting in large economic losses. The tunnel cable channel is divided into the outer part of the hole and the inner part of the hole. The cable duct outside the hole should be cable trench, and the cable bracket is installed to lay the cable, because the number of cables is large. It is advisable to use 3 or 4 layers of brackets, which are arranged on the wrong side of the two sides. In addition, it is suitable to lay the trenches for strong and weak electric cables. The special attention should be paid to the hole sections of the cable ducts outside the tunnel. Because of the narrow area, there are many pipelines and facilities. All parties to the project should pay full attention to the coordination work in the design stage. The hole section generally has cable trenches, ditch, communication pipes and facilities, fire pipes and facilities, monitoring facilities, street lights, safety facilities and grounding, as well as restrictions on the high slope and road surface of the hole. The foundation of the street lamp and other facilities should be made beside the cable trench, which can reduce the pre-embedded threading pipe, and other facilities are also arranged separately. Therefore, appropriate space should be reserved at the entrance of the cave. The lower part of the hole is a cable trench, the upper part is a cable bridge, and the cable bridge should be a steel ladder bridge. The bridge installation is generally located on both sides of the tunnel vault, about 6m away from the road surface, and the two sides should be installed horizontally, strictly exceeding the limit, due to the tunnel There is a large deviation in the lining, and the deviation should be eliminated as much as possible in the installation of the bridge, especially for curved tunnels and slope-changing tunnels. Adjustment measures: 1 Lengthen the vertical arm of the bridge and open the long hole. The length of the extension depends on the deviation of the tunnel wall, generally not less than twice the normal vertical arm; 2 coarse positioning first long distance measurement, fine positioning every 2m, coarse positioning length Depending on the curve of the tunnel, the fine positioning should be adjusted according to the coarse positioning to achieve the following observation as a smooth curve (vertical plane). 3 Adjust the upper and lower positions of the cross arm so that the lateral observation is a smooth curve (horizontal plane). A smooth curve in the three-dimensional space inside enhances its aesthetics. In the engineering practice, the bridge and the cable trench and the cable channel between the bridges generally use pre-embedded pipes, which are pre-buried by the tunnel civil works. Due to the differences in the civil and electromechanical construction processes and the poor overall design considerations, the pre-buried positions are not caused. Correct, the pipe diameter is too small or the pipe jamming phenomenon is not conducive to the construction of the cable pipe, or even the construction. Therefore, the cable trough should be reserved. The cable is installed in the trough, and the fireproof board is used to cover the cable. For pipe pre-buried construction, the pipe bending machine bending process shall be adopted, and the pipe welding shall not be sufficient, and the pipe diameter shall be sufficiently large. It is recommended to use G80 steel pipe. The lighting load has a large starting current and frequent operation, especially in the automatic control state. This 1.7 lightning protection and grounding to UP stabilize the line and the operation of the ship is working. The electric state is shhg. The substation is grounded. In the network, the electrical installation year Chen Xiaogang: the technical analysis of tunnel lighting engineering resistance. The choice of the grounding device connecting the two grounding trunks in the upper and lower sides of the tunnel to all the electrical equipment in the tunnel should be determined according to the specific conditions. Generally, it is stone in the hole. The zone is not conducive to the compliance of the grounding resistance value, and the grounding device should be handled flexibly.

Lightning protection rods or lightning protection belts can be used for building lightning protection. Lightning rods can be installed on the high pole equipment outside the hole, and the metal rods can be used as grounding leads. Lightning protection grounding should be set separately, grounding resistance <10. 2 tunnel lighting technology analysis tunnel because of its special traffic environment, the lighting conditions are very high. In the transition between bright and dark environment, human vision needs to have an adaptation process, in which the adaptation from bright to dark takes a long time, called dark adaptation, and vice versa is called adaptation, which is called tunnel lighting system, ensuring Driving safety. The tunnel lighting system should be set up with the following conditions in mind: environmental conditions: topography near the tunnel, orientation of the hole, field of view near the hole, vegetation conditions, flatness and linearity of the road section outside the tunnel, and meteorological conditions.

Civil engineering design: tunnel length, flat vertical and linear, hole structure, cross section layout and building boundaries.

Traffic conditions: design traffic volume, calculate driving speed, one-way or two-way traffic, car-specific or mixed traffic.

2.1 Tunnel lighting The tunnel lighting includes approach lighting, entrance section, transition section lighting, middle section lighting, exit section lighting, accident emergency lighting and horizontal tunnel lighting. Take a tunnel lighting project as an example, the lighting system settings are shown in Table 1.

2.2 Tunnel lighting standard The minimum average brightness of the inner and outer parts of the tunnel is shown in the table above.

Total brightness of road surface roughness (Lmh/La) (minimum brightness/average brightness)>0.4. Longitudinal uniformity of lane road surface (Lnl/Lmax) (minimum bright maximum brightness on line parallel to the central axis of the lane)>0.6 Table 1 Lighting System Set project length luminaire model layout single side luminaire spacing road surface brightness (d/m2 inlet section 400W high pressure sodium lamp symmetrical arrangement transition section Ltrl 250W high pressure sodium lamp symmetrical arrangement transition section Ltr2 100W high pressure sodium lamp symmetrical arrangement middle section Lin 100W high pressure sodium lamp staggered exit section Lex 150W high pressure sodium lamp symmetrical arrangement cross channel 100W high pressure sodium lamp central arrangement hole outside channel 250W high pressure sodium lamp driving to the left emergency lighting 2X36W fluorescent lamp staggered 2.3 tunnel lighting system function according to day, evening (or cloudy, dense fog days), night Four levels of control are carried out in the middle of the night to ensure the safety of driving and save energy.

The entrance, transition and exit sections of the tunnel are used to enhance the lighting of 400W\100W: the high-pressure sodium lamp is turned on during the day, and the interval in the evening (or rainy and dense fog) is halved and closed at night.

The 100WA high-pressure sodium lamp for basic lighting only turns on the left side of the driving direction in the middle of the night, and the rest of the time is fully open.

The road lighting outside the tunnel is turned on at night and late at night, and is normally closed at other times.

The horizontal channel 100WA high pressure sodium lamp is normally closed, only open in temporary use or in emergency situations. See Table 2. Table 2 Tunnel Lighting Control Parameter Table (Unit: d/m2) Operating Condition Outside Hole Brightness Index Or time entrance lighting section transition lighting section 1 transition lighting section 2 middle section exit lighting section horizontal emergency lighting outside the street light daytime evening and rainy day night night is very important, the curved hole door should be horizontally pushed and pulled due to the transverse arc of the hole wall Type, the upper and lower side of the guide groove, the color is consistent with the decorative color of the hole wall, the material selection of the door panel is the key, the material should be fireproof, have a certain strength and toughness and can be cured after a period of time.

For the linear aesthetics of the luminaire, due to the large error of the tunnel lining, the overall linearity of the luminaire after installation cannot be guaranteed. How to eliminate the civil construction error and ensure the linearity of the installation of the luminaire, there are also two options. It uses a steel to make a standard linear mounting base. The base is laid along the entire wall to achieve an ideal smooth curve. The lamp and bracket are mounted on the base. This solution can fully realize the overall linear appearance of the lamp installation. Convenient, but it is not necessary to install a linear base. How to choose a hole to be opened *Mshin affects the beauty of M along the cost.: / An Mm does not Jt guarantee 3 technical indicators of each set of tunnel lamps technical indicators 400W1 high pressure sodium lamp 4800lm250W' high pressure sodium lamp 28000lm luminous flux 150W high pressure sodium lamp 16000lm100W1 high pressure sodium lamp 9000lm2X36W 'fluorescent lamp 2X3000lm light source life 24000h adaptable voltage 220V 10% open case front door open protection class IP65 lamp housing>25mm thick monolithic high pressure aluminum alloy plate ( Copper-containing <0.4%) stamped to a thickness of >0.8mm, 99.5% high-purity reflector aluminum plate, structurally strong Can withstand cleaning, moving without deformation, anode for oxidation treatment glass mask>5mm thick non-astigmatism temperature resistant tempered glass electrical appliance life 5 years Table 4 Technical indicators of each set of emergency lighting fixtures Technical indicators Project technical indicators Luminous flux 2X3000lm protection grade IP65 lamp power 2X36W discharge time 15000h electrical life 5 years adaptation voltage 220V Shi 2 retrofit lamp support system, in addition to the illumination angle adjustment function also has a telescopic adjustment function perpendicular to the direction of the hole wall. The scheme can better adjust the aesthetics of the luminaire, and the utility model has the advantages of low cost and firm installation, but the adjustment of the luminaire is difficult. The specific form of the support system is as shown.

2.5 Tunnel lighting system Automatic control lighting system The main control appliance is PLC programmable controller. The brightness sensor signal (4~20mA) outside the tunnel hole is transmitted to the programmable controller input module, which is automatically programmed by the CPU module of the PLC programmable controller, and the output signal is automatically controlled by the outlet relay, and then the switch of the low-voltage illumination feeder circuit is performed. Automatic control, at the same time, the open/close status signal of the contactor auxiliary contact of each feeder circuit is input to the PLC programmable controller. Various digital analog signals are processed by the programmable controller and then uploaded to the central control room of the central control room through the communication interface. The monitoring computer and the PLC programmable controller are programmed for the various working conditions of the tunnel lighting. The lighting circuit is turned on and off automatically, and the control system diagram is as shown.

Point NX1S point 16 points MOBIBUSDZ input DI output AI input feedback signal illuminance meter detection signal *Q-turn on light command* to monitoring center control system map western prospecting project 14 lighting fixtures 2.4.1 technical indicators (see Table 3, Table 4) 2.4 .2 support system support system includes all necessary steel, support pins, bolts and other materials.

All support system metal parts and surfaces must be corrosion resistant to withstand harsh environments and harmful gases. The support system should be able to withstand the three times the weight of the supported equipment and the support system itself. There are two main indicators that affect the aesthetics of the tunnel. One is the aesthetics of the luminaire. The second is the decoration of the cave wall. Sheet decoration. Due to the need for electromechanical installation, there are many caverns of different sizes on the tunnel wall, the form of the portal door and

Basketball Jersey

Basketball Uniforms,Basketball Team Uniforms,Plain Baskteball,Basketball Clothes

Guangzhou LIDONG Garment Industry Co., Ltd. , https://www.sportssuit.nl