Study On The Performance Of Electromagnetic Release With Oil Dashpot In Miniature Circuit Breaker

Miniature circuit breaker is the main electrical appliance in the terminal apparatus. Theoil dashpot of the miniature circuit breaker is used to realize the inverse time characteristicsin order to achieve overload protection. When short circuit faults happen, the armature canbe tripped instantaneously to achieve short circuit protection. Because the viscosity of themethyl silicone adopted in the oil cup is stable, protection characteristics of circuit breakerare little influenced by environmental temperature, and it has a good inverse timecharacteristic, so it is used widely, and the used quantity is much more. Based on these, thestudy on the performance of electromagnetic release with oil dashpot in miniature circuitbreaker is put forward.In this paper, on the basis of analysis of miniature circuit breaker, viscous flow damper,computational fluid simulation technology, finite element analysis technology andmultibody dynamics simulation technology, combining with the actual project, the oildamping force, static characteristics and dynamic characteristics of electromagnetic releasewith oil dashpot were studied. First, expression of damping force was derived according tothe law of the fluid theory, and the influence of the parameters on the damping force wasanalyzed. Then with computational fluid simulation software FLUENT, field quantitiessuch as velocity and pressure, data table of damping force under different viscosity weregot. And the simulating data was compared with data obtained by theoretical derivationformula. Afterwards with the finite element software ANSYS, static characteristic ofelectromagnetic release with oil dashpot was obtained. Through the the interface simulationtechnology, static data was embedded into multi-body dynamics software ADAMS, and thedynamic characteristics of electromagnetic release with oil dashpot was got, and simulationresults and measured results of the protection characteristics were compared and their datawas essentially agreed.At last, the influence of the release parameters on its dynamiccharacteristics was discussed. It is shown that the research results have importanttheoretical guiding significance and practical value for analysis, development andoptimization of the electromagnetic release with oil dashpot.