Generally speaking,a bus duct system with a working voltage above 3000 volts is called a high-voltage bus duct.The phase to phase insulation resistance of the high-voltage bus duct should be greater than 1000M ohms,with a high protection level and generally IP54 for outdoor use.High voltage bus ducts are used for connecting power plants,large transformers,and other applications.The shell of the high-voltage bus duct is enclosed,which can greatly reduce the number of power outages and maintenance.When transmitting large currents,it can eliminate faults caused by unbalanced current distribution caused by the use of double or triple high-voltage cables,ensuring the reliability of power supply.

　　High voltage common phase enclosed busbar is a new device for transmitting electrical energy in power generation,transformation,and distribution systems.The working current varies in value,and it has the advantages of simple structure,safety and reliability,low voltage drop,flexible direction,easy installation,and good short-circuit resistance.The sandwich structure of dense busbars has obvious advantages over the grid structure of air busbars in terms of small volume and space occupation;The voltage drop index of transmission lines mainly depends on the resistance,capacitance,and inductance of the transmission lines.Air type busbars have a large space between phases and the shell is made of magnetic material(steel),resulting in obvious eddy current phenomena,large capacitance and inductance,significant voltage drop,and large energy loss;The compact structure of the dense busbar greatly reduces the impedance of the busbar system,while the non-magnetic aluminum magnesium alloy shell further avoids the generation of hysteresis eddy currents,resulting in a very small voltage drop and low energy consumption of the entire system;Low heat generation and fast heat dissipation.

　　The resistance of dense busbars is relatively small,and due to their good heat dissipation function and low temperature rise,the voltage drop and losses of the circuit are also relatively small.The resistance of an air type busbar is relatively high,which is also related to its heat dissipation.It heats up higher,and usually the higher the temperature,the greater the resistance.Due to the low impedance characteristics that air busbars cannot match,dense busbars have smaller heating indicators;There are three ways of heat transfer:convection,radiation,and conduction.The protection level of IP54 determines that the busbar system must be a fully enclosed structure,so convective heat transfer inside the busbar does not exist;The compact structure of the dense busbar determines that its heat transfer mode is"conduction";The existence of a static air medium between air type busbars determines that their transmission mode is"radiation",and the thermal"conduction"between metals is inevitably superior to the thermal"radiation"of gas media;In addition,the thermal conductivity of the aluminum magnesium alloy shell material is much better than that of the steel shell.

　　Air type busbar trunking,due to its seemingly safe surface structure,often uses mid to low end materials in the market for insulation material selection.However,this precisely poses a significant safety risk to its performance.Once this poorly performing insulation material ages,the insulation material falls off and dust accumulates over time,causing phase to phase short circuits in the air type busbar;The structure of dense busbar phases closely adhering to each other determines that the selection of insulation materials for dense busbars is currently internationally recognized for its exceptional performance.