In the synchronous closing operation of the circuit breaker

the change of environment temperature can cause the switching action dispersion increase. In this paper

under environment temperature change

the main factors of circuit breaker closing characteristic are researched

including their changing rules and influence on actuator closing characteristic. By fitting experimental data

the empirical formula between closing time and influence factors are established under the structural parameters of the mono-stable permanent magnetic mechanism vacuum circuit breaker. Research shows that

as the temperature change

the actuator moving parts’ static force（including static attractive force and mechanical damp）is the most important factors affecting the circuit breaker closing characteristics;at the same time

capacitance series equivalent resistance’s change under low temperature also has a great influence on closing characteristics of circuit breaker. The empirical formula can well characterize the relationship between the variables and the closing time

is helpful to the development of synchronous closing technology.