At present

construction and renovation projects of 20 kV power grid are ongoing.Aiming at shortage of 20 kV voltage level power supply equipment

a type of outdoor 24 kV high voltage AC Vacuum Circuit Breaker

rated current 1 250 A

rated short-circuit breaking current 25 kA

has been developed.The paper introduces the whole structure and the spring actuator of the vacuum circuit breaker

simulates and designs insulation structure by using ANSYS software.At the same time

improved project is put forward.