供配电系统论述.doc

Power distribution design for high-rise building fireAbstract This paper analyzes Chinas current power supply and distribution of tall buildings in several fire design, combined with specification and engineering examples for the distribution of the current high-rise building design to explore the problems and propose appropriate solutions.Key words high-rise building fire Supply Emergency Power Supply Power SupplyAs Chinas national economic development, building more and more land, more and more precious land resources, prompting the development of various types of construction to the high-level, so high-rise building fire safety is increasingly a cause-oriented. For the characteristics of high-rise building fires, high-rise building fire safety design should be based on self-defense self-help, while the fire service for the distribution is to ensure the normal operation of the key fire-fighting facilities, directly related to high-rise building fire safety. Therefore, this article from the fire power configuration, fire distribution, fire electrical wiring for high-rise building power supply and distribution reliability analysis, propose appropriate solutions to ensure high-rise building fire safety standards.1. High-rise building fire power scheme1.1 specification power supply requirements for fireAccording to fire protection design of tall buildings (hereinafter referred to as high regulation) provides high-rise building fire power should be the current national standard for power distribution system design specifications, the requirements of the design, a class of construction by a load of required power supply, second-class high-rise buildings should be two power load requirements. According to civil electrical specifications (JGJ/T16-92) provides a load consists of two power supply, when a power failure, the other at the same time the power outage Buzhi Yu; a load is especially important in load, in addition to the above-mentioned two power supplies, theMust also be an additional emergency power supply of the third power; 2 load power should make sure that when the power transformer failure or circuit common failure, without interruption of power supply (or the rapid recovery after the interruption), the load is relatively small or regional power supply The difficult conditions, the two loads can be more than a return to 6KV dedicated overhead power lines or cables.1.2 The composition of high-rise building fire powerFire power is to ensure that high-rise building and fire normally fire-fighting equipment under normal electricity supply. Generally considered the main power supply and pose a fire emergency power supply. When the main power failure, emergency power supply can continue to supply to the fire-fighting equipment. Commonly used in emergency power supply are: (1) independent of the normal power-generating units (2) power supply network, independent of the normal power supply dedicated feeder circuit. (3) battery; (4) dry batteries.1.3 common Fire Power1.3.1 Dual Power high-voltage single-supply bus is not sub -Dual power high-voltage power supply section is not a single bus, two-loop high-voltage power supply at the same time, prepare a normal one to use, in this way to reduce contact between cabinets and a voltage transformer cabinet, saving infrastructure investment, reducing the high voltage distribution Electric room building area is beneficial to both, this approach requires two-way are guaranteed 100% of the load of electricity, when the cleaning bus or bus failure will cause all the power outages, poor reliability of their electricity supply is generally not used in high-rise construction.1.3.2 Dual Power high-voltage single-supply busbar sectionDual power supply high-pressure single-busbar sub-way, two-loop high-voltage power supply at the same time, each other back. High reliability of this approach, particularly for electrical equipment, fire two power requirements at the last and easy to implement the provisions of a switch, which is relatively common wiring.1.3.3 3 power supply high-pressure single-bus sub -Three sub-power high-voltage single power supply bus, three-loop high-voltage power supply, the normal dual-use when a preparation, this approach has a high reliability, suitable for a larger load capacity of the important users.1.3.4 a main high voltage power supply, 380V power supply for the city, emergency power supply networkSmaller building, was not by the consumption, the local access to two power supplies and difficult, in the vicinity have 380V power supply when the main power supply can be used a high-voltage power supply, 380V power supply for emergency power supply. If the economy can also be allowed if the use of diesel generator sets for emergency power supply.1.4 plus the idea of diesel-powered generator setsAt present high-rise buildings, international and domestic universal power supply is based on the dual-power supply was equipped with a diesel generator as an emergency power supply, which is especially important to meet a load of power supply load requirements (Figure 1 does not include the dotted line part of the ). However, dual power plus the power supply of diesel generating sets in most parts of northern China are still subject to weather conditions. As a long time in the north in winter, the temperature low. As an emergency power supply diesel generator sets at low temperatures is difficult to immediately start power supply, and some even two or three minutes can not start.The dual power supply in most parts of 10KV substation quoted from the same strict sense, its essence is a power failure when the substation, the two power supplies also failed, causing power supply system completely paralyzed. In fire cases, this will expand the fire, causing serious losses is not allowed. Therefore, I envisage the dual power on diesel generator sets based on the season, plus a power supply, and enable it to their own independent power supply.In the case of low winter temperatures, reducing the reliability of diesel generators, we will connect the power this season, for increasing theElectric system reliability. When the temperatures rise, we stopped the season to the power supply department reported that power supply, you can save running costs. And this season there are three power options: First, quoted all the way from the substation 10KV high voltage power supply as the season (Figure 1), the advantage of high reliability power supply, the shortfall is that the higher investment in infrastructure; second is from a nearby high-rise buildings along 10KV transformer high-voltage end of the quoted or cited all the way low end of the season as a 380/220V power supply; third all the way from the city network cited as the season 380/200V power supply.1.5 Building Configuration Thinking of diesel generator setsHigh regulation fire-fighting equipment supply should be provided for the power distribution system design specifications GB50052-95 requirements of the design, and the specification of a load is especially important in load did not involve the fire load in their fire power as long as there two power supplies can meet the requirements of high regulation also requires a class of high-rise building fire load electricity requirements should be a power supply, and a distribution box office in the final automatic switching device to ensure that fire safety facilities in When the fire power and reliable, able to function properly. In the high regulation is not clearly defined one, second-class high-rise buildings need to configure the diesel generators.Thus in recent years, newly emerging high-rise building fire load does not require allocating additional diesel generators. However, the specific power supply design, the vast majority of high-rise buildings from the electricity grid connection of two-way line of 10KV power into electricity, which can not meet the specifications where two power supply requirements. System blackout caused either by an internal fault, some caused by power failures, as a regional power grid in the main grid voltage of the upper part is a grid, so the user either from electric power line to take a few back into the line also can not be in the strict sense of the two an independent power supply, power grid failures can cause a variety of all the power into the line at the same time a result of loss of power supplyBlackout. In fact, the Road 10KV high voltage power supply taken from a different substation is very difficult, and diesel generating sets to configure a small investment, the use of good results and will comply with regulatory requirements, so the design of high-rise building shall be fitted with diesel-powered generator sets. I think that explicit requirements specification which can be high-rise buildings should be equipped with diesel generators.2. High-rise building fire distribution2.1 common Fire Distribution ProgramFire distribution methods are commonly used in radiation type, tree type, chain, four kinds of hybrid(1) The radial distribution of the failure of any one line to each other affect each other, the equipment is easy to manage a high supply reliability. However, more than qualifying non-ferrous metals consumed in large quantities, switching equipment, and more investment in higher operating costs for a single piece of equipment of large capacity, power supply reliability high. (Figure 2 a)(2) The trunk-type distribution when the route failure, a larger sphere of influence, but coupled with alternate routes and to achieve switching to improve power supply reliability for a more uniform distribution of places. (Figure 2 b)(3) chain and the trunk-type is basically the same, but the low-reliability than the trunk, when the middle of a piece of equipment failures associated equipment in the back will lose power. (Figure 2 c) (4) Mixed type, including two kinds of radiation type and tree-type distribution method is the victory of more high-rise building in a ligand distribution method. (Figure 2 d)2.2 The current issue of widespread distribution(1) of the fire electrical equipment such as fire control room, fire pump fire power instead of using a dedicated power supply, while the use of general load on the socket for the power lines, so that in case of fire in the building off the main power supply After the fire power the devices power also will be without electricity and fire-fighting equipment paralyzed, its fire immeasurable loss.(2) Some spare each other, such as fire pumps, fire fighting equipment at the end of the focus on two power each vote, there is no use of the equipment are radiation from the fire power supply power distribution room, but from the power distribution room leads to a main line, in the Preparation of the end of each parallel equipment. The result is that once the main line causing the problem (and the main line caused a great chance of failure) in each stand to lose power devices are unable to start, without achieving the desired results.(3) sharing power distribution equipment, fire linkage, there is no requirement of the end of the distribution box is located two-way automatic switching devices, or automatic switching devices of poor quality, low reliability. In the fire case, the standby power can not automatically switch to emergency power supply, power supply interruption. Some use the manual switch, when the firefighters reached the scene and then look for the power switching devices to switch, which will delay aircraft, resulting in heavy losses.2.3 The solution to the problem(1) Normal working power supply and emergency power supply shall be self-made system, independent distribution. When the power supply and lighting separately, then the power and lighting should be available to work the power distribution system and emergency power distribution system. Ensure that a class load of fire, electricity and other conditions in the fire, by the emergency power supply a continuous power supply, second-class load to ensure two-loop switching power supply.(2) In the fire power distribution design and installation of electricity, the power consumption of the large or a higher concentration of fire power equipment, such as fire control room, fire pumps, power distribution room should be the introduction of radial supply, and to ensure that the main equipment and standby equipment, power lines independent of each other.(3) Fire system equipment, power distribution share should be in the most power distribution boxes located at the end of two-way automatic switching device, and install high-quality power supply automatic switching devices. If you are installing a manual switching device, it is desirable that the equipment room distribution box. So that in case of emergency fire personnel can be easy to find and achieve in a short time to switch.3. Guanfang Hotel Fire Design and Analysis of Power Supply and Distribution3.1 Basic InformationGuanfang Hotel is located in Lijiang City, Snow Mountain Road, basement, ground floor 21, is a five-star hotel, belongs to a class of tall buildings. 10kv high voltage power supply to its dual-supply single-bus sub-power supply, auto-switching. Normal working hours, while two-way power supply, each other back and each shoulder 50% of the load. Power failure the way, another way for the full load power. No diesel generator sets. Route high-pressure system and low-voltage power distribution systems approach basically uses radiology systems, floor distribution system is a composite style, power distribution wiring the main trunk with Caine wells.Set up their fire power devices are used end of the dual power automatic switch device.3.2 Reliability Analysis of Power Supply and DistributionAccording to the high regulation in requiring the construction of tall buildings is a class, according to civil construction for the distribution design standards should be equipped with two power supplies to power. In the actual design and construction which uses a dual-supply single-busbar sub-10kv power supply, the fire control room, fire and other fire-fighting equipment lift the power supply distribution box office at the last one set up automatic switching device. Seems to meet the specification requirements, but the two power substations with the quote from Xiangshan, its essence is a grid of two loops, rather than two separate power supplies. When the substation failure on the entire power supply system is paralyzed.The Lijiang city alone, within a substation, from another independent quoted a power substation is very difficult, plus Lijiang Xiangshan substation is Daito hydropower electricity, hydroelectric power supply by the seasonal impact of the dry season, a power generation a small amount of the allocation of power followed by scoring city, stopped a battery compartment for a time. This will significantly affect the building power supply system reliability.At the same time as two-way 10kv power supply, spare each other, according to the capacity of transformers included in the regular standby fire pumps, spray pumps and other fire-fighting facilities to choose the load, while the buildings fire load of about 900kw, non-fire load of about To 3000kw, its infrastructure investment in high operating cost more. This is just one company rather than a compliant design of the economy.In the power supply system installed in an automatic removal of loading device, when the system automatically removed when the fire with the fire of non-electrical equipment, transformer fire on a bus load of electrical equipment to prevent the spread of fire and fire electric shock accident occurred.The building is divided into 8 by function power partitions, each partition also on the electrical load level, the function of each layer according to power, lighting, two separate power distribution systems. The fire district for each power supply are two power supply electrical equipment, and a distribution box office at the last auto-switching, so that the design complied with the specifications, in the case of fire, firefighters in time understand the fire parts of the site-specific, accurate and starting the fire pump, sprinkler pump and other fire-fighting facilities, the timely removal of parts of the fire power.3.3 The improved design of the programWas equipped with an auto-start diesel generators as an emergency power supply. The two parts to the fire-fighting equipment from the power supply, the first part is from the mains supply, the second part of the power supply from diesel generators, and the last one automatically switch distribution box office. When the main power fails, by diesel-powered generator sets to the entire building. As the working electric power supply and power backup power, diesel generators only power supply and backup power at work when no electric starter. This will greatly enhance the power supply system reliability.Two-way 10kv power supply can be designed into the way to work all the way back. Power Supply by line consideration, according to the work of standby power after the power failure to maintain the main building elevator, room lighting load calculation. When a fire removal of non-fire power, auto-connected to fire pumps, sprinkler pump and other fire-fighting facilities. This will reduce the transformer capacity, was equipped with diesel generator set up for supply reliability. Such infrastructure investment, high economic efficiency.In various fire-fighting equipment of the power supply on the power distribution according to the respective features, fire pumps, spray pumps, fire lifts, fire control room, smoke fans, etc. due to large capacity, high reliability requirements, can be designed dual power supply, radial distribution