Research On Motor Operating Machanism In126kV Vacuum Circuit Breaker

In order to solve the problems exist in operating mechanism in high voltage circuitbreaker such as complex motion system, high mechanical failure rate, poor motion controlcharacteristics and low intelligent control level, this paper has taken a126kV single-breakvacuum circuit breaker as the research object to carry on the research that from the aspectsof dynamics characteristics analysis, mechanical operating characteristics test, motorstructure design and practical engineering application. On this basis, an asymmetricwindings permanent magnet swing angle driving motor (AWPMSADM) which applied tomotor operating mechanism of high voltage circuit breaker has proposed. The mainresearch contents of this paper are as follows:(1) The equivalent load torque and the motion coordination characteristics betweenvacuum circuit breaker and motor actuator are researched. The motion analysis model ofmotor is established and motion relationship between driving motor and insulate pull rod isderived. Meanwhile, the moving components of vacuum circuit breaker, which has reducedto the equivalent moment of inertia and load torque in the side of motor spindle, havecalculated by employing analytic method. Based on the analyses above, the angle ranges ofdriving motor, the trend of equivalent moment of inertia and the peak value of load torqueduring the process of circuit breaker’s opening and closing operation are obtained.(2) The dynamic characteristics of driving motor with different rotor structures areresearched. Mechanical kinetic characteristics and transient electromagnetic characteristicsof driving motor with four different rotor structures, such as surface embedded mountedtype, dovetail groove pressing type, linear embedded type and out-V embedded type, areanalyzed by employing coupled field-circuit-motion method. The results indicate thatdriving motor with dovetail groove pressing type has better performance on the kineticcharacteristics, electromagnetic characteristics and mechanical reliability. The virtualprototype simulation model of motor operating mechanism for vacuum circuit breakerwhich has verified by experiments is established and the motion characteristics of theactuator are analyzed. (3) The mechanical operating tests of vacuum circuit breaker driven by motor actuatorare carried out. The prototype of driving motor with dovetail groove pressing type hasdeveloped and testing platform combined vacuum circuit breaker and motor actuator isestablished. A series of experiments which consist of opening and closing operation test,automatic reclosing operation test, operating stability research test and constant andinterval velocity governing test are carried out. The test results suggest that the velocitycharacteristics of vacuum circuit breaker driven by motor actuator are satisfied withrequirements of vacuum circuit breaker and the operating stability performance is fine.Simultaneously, the PWM voltage control method can achieve the movement control ofmotor actuator effectively.(4) The overall design scheme of AWPMSADM and the asymmetric starting-breakingwindings structure are proposed. The design flow diagram of main structure parameters ofAWPMSADM are given clearly. The transient mechanical and electromagneticcharacteristics of AWPMSADM with four different rotor structures which consist ofsurface mounted slot type, subsection surface mounted slot type, subsection embeddedtypeⅠ and subsection embedded typeⅡ are analyzed in detail. Besides, the asymmetricstarting-breaking windings aimed at improving the starting torque and achieving electricbreaking is designed. The influences of different winding distributions on dynamiccharacteristics of AWPMSADM are studied by using finite element simulation method.Ultimately, the overall design scheme of AWPMSADM is proposed.