The Research on the Design and Application of Night Lighting in Football Field

Figure 1: Schematic diagram of a light pollution-free stadium

The lighting design criteria must meet the standards in the following table

In order to avoid light pollution caused by the night lighting of the stadium to the surrounding area, all flood light fixtures use medium/narrow angle. If necessary, a special light guide plate will be installed to completely guide the beam into the stadium without direct exposure.
Go to the neighboring houses around, so as not to arouse public disgust. The lighting environment of the audience is further considered to avoid glare.
Control the projection angle within the range of 65° of elevation, and make the shadows overlap in the direction to make the most uniform review to make this field
1.The vertical illuminance listed in the table refers to the illuminance facing the camera.

Table 3  Lighting Design Benchmark Table

		Vertical Illuminance			Horizontal Illuminance			Light Source
		Eav	U0		Eav	U0		CCT	CRI
Class	Camera	Lux	U1	U2	Lux	U1	U2	Tk	Ra
International Competition Class V	Fixed	2400	0.5	0.7	3500	0.6	0.8	>4000k	>70
	Field	1800	0.4	0.65
International Competition Class IV	Fixed	2000	0.5	0.65	2500	0.6	0.8	>4000k	>70
	Field	1400	0.35	0.6

2.The illuminance value listed in the table is the illuminance that should be maintained during the event; the efficiency of the lamp should be calculated as 0.7, so the actual number of fixtures should be
Three times the standard listed in the table
3.The glare grade of all grades listed in the table: GR 50
4.Illumination difference (every 5 meters) of all grades listed in the table: ≤ 20%

Table 4  Lighting Design Benchmark Table

		Vertical Illuminance			Horizontal Illuminance			Light Source
		Eav	U0		Eav	U0		CCT	CRI
Class	Camera	Lux	U1	U2	Lux	U1	U2	Tk	Ra
Domestic Competition Class III	-	-	-	-	750	-	0.7	>4000k	>70
International Competition Class IV	-	-	-	-	500	-	0.6	>4000k	>70
Training and Recreation	-	-	-	-	250	-	0.5	>4000k	>70

1.Illumination difference of all levels listed in the table (per 10 meters): ≤30%
2.The illuminance value listed in the table is the illuminance that should be maintained during the event; the lighting efficiency should be calculated as 0.7, so the actual number of fixtures should be 1.4 times the standard listed in the table.

Safety Concerns
Because Taiwan is located in the typhoon earthquake zone, both typhoons and earthquakes have brought great damage to large lighting poles. Therefore, in the calculation of the wind resistance structure of the light pole, the calculation formula of the American AASHTO 1985 is used, which is sufficient to resist the super strong typhoon with an average wind speed of 75 m/sec and a maximum instantaneous gust of 91 m/sec, and its wind resistance pressure is greater than that of the building technical regulations. Wind regulations. According to the building technical regulations, Taiwan belongs to the earthquake zone. In addition to complying with building regulations in the seismic design of light poles, the structure must be specially strengthened to increase the safety factor to resist unpredictable large earthquakes.
Lighting Equipments
Pole
According to international competition standards, there are four lighting poles designed in this field, the pole height should be 46 meters, and the average center height of the floodlights for each pole is 43 meters. There are 366 2000W composite metal floodlights installed in the whole area, and 84 lamps in each of the four poles, so that the venue lighting can meet the design requirements. The light pole is made of high-tensile steel plate, and is hot-dip galvanized anti-corrosion treatment according to ASTM A123. The thickness of the galvanized film is required to be 70 Mircon or above, in order to maintain the corrosion resistance for 30 years or more. The anti-earthquake strength of the light pole fully meets the seismic force requirements stipulated by the Construction Department of the Ministry of the Interior. The foundation part uses reinforced concrete with a value of more than 4000 PSI to ensure the safety of the light pole. A lift maintenance truck is attached, so that maintenance personnel can climb to the top to repair the bulb or adjust the angle.

LED Luminaire
Take wind-resistant, waterproof, shock-proof and anti-corrosion products. The light source is a 2000W metal halide bulb with high color rendering, with color rendering > Ra 90, color temperature of 5000K or above, and luminous efficiency of 85Lum/W. Generally, it takes 15-20 minutes to restart the metal light bulb if the power is cut off after lighting. Therefore, in order to ensure that the game will not be interrupted in the future and for safety reasons, it is planned to use some of the light bulbs to restart immediately, so that the lighting can resume power supply. , the split start lights up. The lamps configured in the whole area include diffused type, concentrated type, different light intensity curve type and immediate hot start type lamps. The lamps have a small wind resistance area, are light in weight, and match the wind pressure of the lamp post to calculate the bearing capacity. The most suitable lighting conditions are set by the computer control system. The lamps use high-efficiency lumens (100 LM/W) bulbs, together with high-efficiency ballasts and capacitors, so as to save energy and reduce the weight of the lamp post. , which improves security. When the power is cut off, the emergency power supply of the site will automatically jump over the generator, and the instant hot-start lamps will be ignited in a very short period of time, thereby maintaining the safety of the site evacuation.

LED Driver
Use high power type, the power factor should be 90% or above, and suitable for AC 220/380V 60HZ power supply system. The ballasts of each light pole are placed in a steel ballast box, and a ventilation fan is added to dissipate heat.

Safety Equipment

Lightning Rod
In accordance with the relevant provisions of the building technical regulations, a set of lightning rods is set at the top of each light pole to protect the steel pole and lighting fixtures. Due to the high height of the light pole, its protective radius is sufficient to cover most of the venue, and lightning rods are set up to protect the areas that cannot be covered.

Pole Grounding
In addition to the grounding of the lightning rod, another set of poles is set to ground to prevent leakage of electricity and hurt people, or when lightning strikes the column, the high-voltage electricity can be smoothly introduced into the grounding system for safety.

Aeronautical warning light
A set of low-light aviation warning lights are set at the top of each light pole. The characteristics and setting methods of lamps and lanterns are designed in accordance with the traffic technical standards and specifications for the setting of air transport obstruction lights.

Security Fence
To prevent spectators from climbing the light poles, safety fences of about 2 metres in height and warning signs were erected around the poles to ensure safety.

Emergency Light
Four 1000W quartz floodlights are added on each light pole, and connected to the independent lighting power supply system. When the Taipower high-voltage power supply system is powered off, the system can immediately supply the minimum safe illumination of 5LUX or above in the field. 

Lighting Performance

To hold international football matches, the lighting must meet the needs of international lighting standards for users of various occasions and properties, such as
1.Players
2.The technicians, the referees, the stadium staff
3.Audience: including when entering the field, when the game is in progress, and when the game is over
Players, referees, and technical staff must be able to clearly understand and see everything that is happening on the pitch so that they can perform at their best; and spectators must be able to clearly see the players and referees on the pitch and other technical staff With its surrounding environment, that is to say, although the spectators are far away from the center of the stadium, they must still be able to clearly see the players and their surroundings at the same time. In addition, the lighting equipment of the stadium also needs to be safe when entering and leaving the stadium. guide the audience. Therefore, the lighting in this case not only provides lighting for the football field finals, but can still provide lighting needs for various track and field sports and civic activities in the future.
4.The lighting standards related to the lighting design of this case include horizontal illuminance, vertical illuminance, uniformity of lighting levels, glare limit, light projection mode and shadow, color temperature and color rendering. Among them, the horizontal and vertical illuminances have the greatest impact on the entire stadium.
Comfort Leve
To create good comfort, the quality of lighting is very important, and to create good lighting quality, it is necessary to have good lighting uniformity and glare control.
Uniformity
The main reason is to prevent the light-dark ratio of the light from being too large, which makes it difficult for players or spectators to identify the ball or other objects on the field, as shown in Figure 2 below.