The influence of busbar bending angle on high and low voltage switchgear

During the bending process of the busbar, its contact surface will undergo slight changes, resulting in an increase in contact resistance. According to experimental data, for every 5-degree increase in the bending angle, the contact resistance increases by an average of about 5%. The increase in contact resistance will not only cause local heating, but in severe cases, it may also cause electrical fires, posing a threat to the safe operation of the power system. According to relevant research, contact resistance is closely related to the flatness and contact pressure of the contact surface. Busbars with excessive bending angles are more likely to have poor contact problems at the connection.

When the bending angle of the busbar is too large, the electric field distribution around it will be distorted, resulting in uneven electric field strength. Studies have shown that when the bending angle exceeds 15 degrees, the unevenness of the electric field strength increases by more than 20%. The increase in local electric field strength may trigger corona discharge, which not only causes power loss, but also poses a threat to the safety of surrounding equipment and personnel. Harmful gases such as ozone and nitrogen oxides produced by corona discharge will also accelerate the aging of insulating materials and shorten the service life of equipment.

When the bending angle of the busbar is too large, the electric field distribution around it will be distorted, resulting in uneven electric field strength. Studies have shown that when the bending angle exceeds 15 degrees, the unevenness of the electric field strength increases by more than 20%. The increase in local electric field strength may trigger corona discharge, which not only causes power loss, but also poses a threat to the safety of surrounding equipment and personnel. Harmful gases such as ozone and nitrogen oxides produced by corona discharge will also accelerate the aging of insulating materials and shorten the service life of equipment.

The busbar will produce stress concentration during the bending process, especially in the parts with large bending angles. Stress concentration will lead to a decrease in the mechanical strength of the busbar, and it is easy to break or deform in a long-term operation under a vibration environment. Statistics show that the probability of busbar breaking increases by 15% when the bending angle exceeds 10 degrees. Broken or deformed busbars not only affect the normal transmission of electric energy, but may also cause more serious electrical accidents.

Too large a busbar bending angle will affect its installation accuracy, resulting in unevenness and looseness at the busbar connection. The reduction in installation accuracy not only increases the contact resistance, but may also cause vibration and looseness of the busbar, thereby affecting the mechanical stability of the entire switch cabinet. Studies have shown that the flatness and tightness of the busbar connection have a vital impact on its electrical performance and mechanical strength. For every 1 mm increase in unevenness, the contact resistance increases by about 10%.

Improper busbar bending angles will reduce its impact resistance, and it is more likely to be damaged when subjected to short-circuit current shock or external force shock. Data shows that the impact resistance of busbars with a bending angle of more than 15 degrees is reduced by more than 20%. The huge electric force and external force generated by short-circuit current may cause the busbar to deform or break, posing a threat to the safe operation of the power system.

Excessive busbar bending angle may obstruct the heat dissipation channel, resulting in the inability to dissipate heat in time. Data show that for every 5-degree increase in the bending angle, the heat dissipation efficiency decreases by about 8%. Heat accumulation not only accelerates the aging of insulating materials, but also may cause the temperature of the busbar to rise, thereby affecting its electrical performance and mechanical strength. Studies have shown that for every 10°C increase in the temperature of the busbar, its service life will be shortened by half.

Improper busbar bending angle may lead to an increase in local current density and the formation of hot spots. Hot spots not only cause local overheating, but may also trigger a chain reaction, leading to an increase in the temperature of the entire busbar system. Data show that the temperature at the hot spot is 15-20°C higher than that in the normal area, accelerating the aging rate. The formation of hot spots may also be related to factors such as the material, processing technology and installation quality of the busbar.

Excessive busbar bending angle increases the difficulty of maintenance and repair, especially when the busbar needs to be replaced or repaired. The bent busbar is not only difficult to disassemble and install, but may also pose a threat to the safety of maintenance personnel. Data show that for busbars with a bending angle of more than 10 degrees, the maintenance time increases by about 25%. The increase in maintenance difficulty not only prolongs the downtime of the equipment, but also increases the maintenance cost.

Due to the degradation of electrical performance and reduced mechanical strength caused by improper busbar bending angle, the equipment requires more frequent maintenance and maintenance. Data show that for busbars with a bending angle of more than 15 degrees, the maintenance cycle is shortened by about 30%. Frequent maintenance not only affects the normal operation of the power system, but also increases the operating costs of the enterprise.