Research And Application Of Prefabricated Cabin Secondary Combined Equipment Structure And Inside Temperature Control

With the development of economy and society,the demand of power energy is increasing.The power grid comprehensively promotes the modular construction mode with high technology content,low resource consumption and less environmental pollution.The prefabricated cabin secondary combined equipment can fulfill the requirements of modular construction in 500 kV and above substations in the power grid.The key to ensure the safe,reliable and stable operation of the prefabricated secondary combined equipment is the prefabricated cabin structure and the cabin environment control.In view of the above key issues,this paper studies as follows:(1)Prefabricated Cabin structure.Through the investigation,analysis and simulation calculation,it is determined that the type II cabin framework uses open type steel,HM250×175 type steel is used around the bottom,and Q235 B is used as the material to realize comprehensive anti-corrosion treatment and fulfill the safety life demand;the cabin maintenance material uses FC Board.The Prefabricated cabinet in cabin uses rack type structural system(rack unit width 700 mm,depth 600mm),and the optimization arrangement of secondary equipment is arranged to fulfill the layout of various standardized devices.(2)Intelligent environment control in cabin.A new type of heat and insulation scheme is proposed: active external reflection and passive internal insulation.External reflection insulation uses thermal reflection insulation coating and internal insulation uses VIP inorganic vacuum insulation board.At the same time,type II and below prefabricated cabin is equipped with 4kW cabinet industrial air conditioner,400m3/h exhaust fan and exhaust filter to ensure micro positive pressure in the cabin.The intelligent environment control system in cabin can automatically detect various environmental variables inside and outside the cabin,and automatically control the environment state in the cabin,so as to ensure that the environment in the prefabricated cabin can fulfill the requirements of staff comfort and safe and reliable operation of secondary equipment.(3)Modular prefabrication scheme for 500 kV substation is innovative designed: 500 kV system is grouped in series and I-type prefabrication cabin is set according to series;Main transformer system and 35 kV system are divided into groups by main transformer and I-type prefabrication cabin is set according to main transformer unit;Secondary equipment of 220 kV system adopts the design scheme of local decentralized layout and centralized layout of prefabrication cabin.Single interval protection,measurement and control uses local device Arranged at the primary equipment site.The 220 kV public part of the whole station is equipped with type I prefabricated cabin according to the bus section.The feasibility andsuperiority of prefabricated module construction in practical engineering application are verified through the further analysis of this scheme.