The kinetic energy parameters of vacuum circuit breakers (mainly related to the kinetic energy output by the operating mechanism, including opening/closing speed, operating work, energy transfer efficiency, etc.) are key factors affecting their core performance. The specific impacts are as follows:
During the breaking process, the contact separation speed is one of the core kinetic energy parameters.
· If the opening kinetic energy is insufficient, the contact separation speed will be too slow, leading to prolonged arc duration. In vacuum interrupters, arc extinction relies on the vacuum insulation gap formed by the rapid separation of contacts. Excessively long arc duration will cause overheating and intensified ablation of the contact surface, and may even lead to breaking failure due to excessive arc energy (especially when breaking short-circuit currents).
· Although excessively high opening kinetic energy can accelerate arc extinction, it may cause a surge in contact collision stress, leading to fatigue damage of components such as the interrupter bellows, and may also generate excessive operating overvoltage.
The kinetic energy during closing mainly affects the contact quality and closing reliability.
· Insufficient closing kinetic energy will result in too slow contact closing speed, which may cause arc ablation of contacts due to prolonged pre-breakdown time, or increased contact resistance due to insufficient contact pressure, leading to excessive temperature rise during operation.
· Excessively high closing kinetic energy may cause contact bouncing (temporary separation after closing), generating secondary arcs and exacerbating contact wear. Meanwhile, excessive impact force will increase the stress on the mechanical structure, reducing the overall service life.
The mechanical life of vacuum circuit breakers (usually measured by the number of opening and closing operations) is directly related to kinetic energy parameters.
· Unreasonable design of kinetic energy parameters (such as excessive peak force, severe energy fluctuations) will cause the operating mechanism (such as springs, connecting rods, bearings, etc.) and interrupter components to bear frequent impact loads, easily leading to faults such as fatigue fracture and deformation, significantly shortening the mechanical life.
· Stable kinetic energy output (achieved by optimizing mechanism transmission efficiency, for example) can reduce component wear and extend service life.
· Excessive energy loss during kinetic energy transmission (such as mechanism jamming, uneven frictional resistance) will cause deviations between the actual output kinetic energy and the design value, which may lead to problems such as unstable opening/closing time, refusal to operate, or misoperation, seriously affecting the safety of power grid operation.
· Factors such as ambient temperature and humidity may indirectly affect kinetic energy parameters (such as changes in spring stiffness). Insufficient parameter margin will further reduce operational reliability in low-temperature or high-humidity environments.
