Design Of Power Supply And Distribution System In Electrical Building

A senior independent commercial office building in Beijing as the background,according to the characteristics of the high-rise public buildings,such as the large number of electric equipment,large load,load type,reserved load,distribution system,large number of units,complex distribution lines and so on.Detailed analysis and classification of electricity load of the building,select the appropriate transformer,reactive power compensation,power cable,power distribution room layout and design of lightning protection and grounding,and then complete the preliminary design of the power supply system building.In this paper,the design of power supply and distribution system has been completed,the need for the next step,that is,the preliminary design of power supply and distribution.The calculation load is calculated by the method of coefficient of demand and unit area power.At the same time need coefficient and coefficient of power equipment multiplied by the calculated directly calculated load;in electric equipment and power units cannot be determined,calculation of load power per unit area.The calculation load is classified and classified,and the total active power and reactive power are determined.Then the suitable transformer and reactive power compensation device are selected to check the power quality.According to the working conditions,select the appropriate high and low voltage switchgear,determine the connection and power supply mode.The load is evenly distributed on the low voltage switch cabinet according to the grade,and the power supply reliability is ensured.According to the characteristics of high voltage switch cabinet,transformer substation room,to conduct site selection and layout.After determining the position of the low voltage switch cabinet,the selection of the outlet cable bus and the choice of the laying mode.Check the voltage loss,rated current,allowable temperature rise and so on.Finally,the lightning protection and overvoltage protection and grounding system are designed.Electrical and electronic systems in the building will cause equipment damage due to lightning,lightning electromagnetic pulse,static electricity,etc.,or unreliable grounding equipment damage or shock.Therefore,must according to the lightning protection level of the building,the rational layout of lightning protection and grounding system,building to ensure safe use of electricity.In addition,the construction of civil air defense works.Need to make reasonable design of civil air defense power supply and distribution;At the same time,the construction process,we must pay attention to the use of the envelope wall,usually in advance of the embedded closed rib.The design scheme of high-rise public buildings is more complex than that of residential and plant power supply and distribution systems.The main reason is that there are many kinds of load and lightning protection grounding system.So it is necessary to load classification analysis,comprehensive layout of lightning protection and grounding system,thus completing the building power distribution system design,to ensure the power supply reliability,the design meets the requirements of construction drawings.