Election and engineering design points of the generator set

[Question] What is the choice of generator set and engineering design?

[Solution] First, emergency diesel generator set selection

The emergency diesel generator is used in the city's electric power failure, mainly supplying power to the first level load, ensuring that the fire is not lost. Generally, the first-level load of civil buildings is roughly:

1, fire equipment: such as fire elevators, fire hydrant pumps, spray pumps, exhaust windows, positive pressure blowers, rolling doors, fire alarms, anti-smoke valves, safety and security devices, etc .;

2, lighting: accident lighting, evacuation marker lighting, aviation disorder light, etc. Emergency diesel generator sets for emergency use, often in standby emergency starting state, continuous operation is not long, generally no more than 8h, so it can be determined by \"Alternate Power \" to determine capacity.

According to the sum of the capacity of each of the above loads (no alternate capacity), the atmospheric correction unit capacity is considered, and the start requirements of the large motor in the above load can be satisfied, and the capacity of the emergency diesel generator set is determined. Emergency diesel generator set, generally selected 1 automation, speed 1500-1000r.p.m, brushless, 400 / 230V, three-phase four-tone control screen, charge and discharge equipment, and generator sets of shared chassis. The shared chassis can be required to reduce the pipeline and occupation area.

The main switch between the mains power supply and the emergency generator power supply, in addition to the electrical interlock, there must be mechanical interlocks to ensure that the emergency generator set does not supply power to the mains network.

Second, the choice of spare diesel generator set

In order to facilitate life, business activities are not paused, consider power supply to the following load: General elevator, living drinking water pump, living water supply and drainage pump, accident lighting, evacuation mark, lighting, fire alarm device, security device, etc.; shopping malls, restaurants, Multi-function hall, lighting, air conditioning and ventilation electricity, shopping malls, etc.

1. The sum of each of the above load capacity is multiplied by a calculated load after the coefficient (the capacity of the emergency diesel generator set is determined) (the alternate coefficient is considered 1.2, that is, the calculation capacity is less than the emergency diesel The capacity of the generator set is supplied from the emergency generator set to the load to ensure the normal operation of life and business.

2, the sum of the above load capacity, multiplied by the calculation load after the coefficients is greater than the capacity of the single emergency diesel generator set (the determination of the capacity of the emergency diesel generator set and the calculation load is determined), can be selected 2 types and capacity Power generator sets close to the regulation and speed control. After the electric power failure, one of the two or two units is electrically powered by electricity and commercial electricity; when the city is powered off, it is powered by the 2 units to the fire load, and the fire is maintained.

The alternate diesel generator sets selected 2 sets to meet the following conditions: model, the same capacity is the same, the pressure regulation, the speed is similar, the automation unit, the unit speed is 1500 ~ 1000R.pm, no brushless magnetic, 400 / 230V, three-phase four lines , With a control screen, charge and discharge equipment, a shared chassis. The chassis can be used with a daily use fuel tank. Between the switching main switch of the main electric power supply, the main switch of the power supply, there is also a mechanical interlock to ensure that the generator power supply does not supply power to the main network.

Third, diesel generator set station design

1. In civil buildings, especially commercial commercial housing, diesel generator sets should be located in the underground layer.

Some venues for noise, vibration, and smoke, or indoor uncomfortable places, low noise box diesel generator sets, which are located in a place with a certain distance from the building to meet the above special requirements.

2, machine room layout

(1) Diesel generator set in the computer room, in addition to the end of the heat sink, the remaining layout requirements, please press \"civil construction electrical designspecification\"JGJ / T16-92 Table 6.1.3.2 Design.

When the heat dissipation tank is less than 250 mm, the hot air can be opened directly to the wall. When the heat dissipation tank is 600 ~ 1000mm, the introducer of the air cover is placed out of the outdoor, and the guiding cover is flexible between the air cover and the heat dissipation tank.

The net higher in the generator station room is generally twice as high as the generator set, and at least 1.5m higher than the generator.

(2) When the motor power is greater than 500kW, it is recommended to install 16 to 20 # 工字 钢 under the roof above the unit to install the lifting equipment.

(3) Some generator sets must install the daily fuel tank, and the daily fuel tank capacity is generally satisfied with the full load operation requirements of 3 ~ 8h. The daily fuel tank must be higher than the oil pump of the diesel engine, and can be installed with a bracket. The outlet exit must be more than 100mm above the fuel tank to protect the hogging of the tubing.

In some places, the fire sector has a hard standardization of the daily fuel tank (independent of the generator capacity), and the daily fuel tank must be installed in a separate fire-free room and must have an accident storage pool. To this end, it is necessary to choose to understand the relevant department. When needed, the oil storage tank is buried in an outdoor ground so that the external fuel can be removed after an additional time.

(4) Emergency (spare) diesel generator station, generally does not have a separate control room.

(5) General production plants provide exhaust volume of each diesel generator set, based on the principle of importance is greater than the amount of exhaust, so that the effective area of ​​the exhaust 100-page window can be obtained. Since the generator room is generally in the underground layer, there should be a sufficiently large venting vertical direction, which is advantageous for eliminating noise. The introduction of Fengfeng page is generally located at the tail of the generator, and the exhaust 100 page window is located in the corresponding position of the introduction of the Fengfeng Page window. If it is difficult to do the above requirements due to the position of the basement, the hot air discharged is not to be sucked into the room, otherwise it will not be able to do fresh, clean and cool down, and the area of ​​the ventilation shaft can be invited. solve.

The radiant heat dissipated by the generator, a diesel engine, and the exhaust pipe, and it is also necessary to use mechanical ventilation or natural ventilation.

(6) The exhaust gas of the diesel engine has the characteristics of high noise, high vibration, high temperature, and the exhaust pipe should be connected to the indoor portion, and the indoor \"Sprotel Menssender \" is ranked outdoors or flue, The flue is beneficial to reduce noise and prevention pollution. Since the exhaustive temperature is high (generally 500 ° C), ordinary clay bricks are smoked, and they can't do their durability. It is advisable to build a refractory brick. The inner segment of the exhaust metal pipeline must be insulated, the surface temperature of the insulation layer is preferably no more than 60 ° C.

Exhaust emissions and dust removal of diesel engine groups, please consult with the local environmental protection department.

(7) The foundation of the diesel generator, generally 200 concrete structures, the base length, wide as the unit shared chassis, and the width plus 200 ~ 300mm, the foundation is 50 ~ 200mm, the base thickness: h = k 稧 / D Bamboo

Where: H-foundation thickness (m) K-weight multiples 1.5 ~ 2 g-unit total weight (kg) D-concrete density 2400kg / mm3 b - foundation width (m) L-base length (m)

The unit base is not reserved, and the damper (or rubber shock pad) is placed under the chassis chassis when installing, and the shock absorber is fixed to the base with expansion bolts. If necessary, there is an anti-seismic ditch around the foundation to provide better protection for buildings. The shockproof gauge width is 25-30 mm, and the depth and foundation are flat. The ditch is placed in yellow sand or wood chips, or the mixture of the two.

(8) Except for the diesel generator station, the remaining faces must be installed with sound absorbing materials. The inner wall of the machine room is uniformly filled in the porous plate interlayer, both sound absorption and sound insulation, and flame retardant. Additionally, the wind and exhaust are passed through the exhaust chamber and intake chamber, which can effectively sound absorbing and lower noise.

Fourth, coordination with other types

1. Provide information to the civil engineering

(1) Long, wide, high and flat arrangement of generator stations, minimum size (length, width, high) and transport channels for long, wide, high and ramps and minimum turn radius. Requirements for the land floor of the machine.

(2) Total unit

The foundation is long, wide, high (high degree of the height of the ground), the depth of the foundation.

(3) The model, specification, specific planar position, and the length and starting point of the IB steel.

(4) Various intake, exhaust caves, exhaust pipe outlet, size size, Baodao has a hundred-page window, etc.

Indoor cable gullet, water ditch and tubing plane arrangement, the position of the stop point, the width of the groove, and the special requirements.

The position, long and wide and dustproof and drainage requirements of the exhaust shaft.

(5) Fire and noise reduction requirements in the generator station.

2. Provide information to the water supply water

(1) Water supply and water supply points.

(2) The position of the drainage and drainage points.

3, provide information to HVAC

Provides indoor radiant heat and corresponding cooling and winding measures.

4. Other issues that have not been involved, execute according to\"Civil Building Electrical Design Specification\".