The Research And Design Of Medium Voltage Earthing Switch

The demand for electricity in the whole society is growing exponentially.With the scale and capacity increasing,the power system security and reliability are becoming more and more challenging.Earthing switch is one of the largest and the most widely used devices in the grid.The ability and reliability of earthing switch plays an important role in the security of power grid operation.Grasping a set of systematic design methods and test methods is an effective way to improve product reliability and stability in the development phase of medium voltage earthing switch products.Based on the research needs of medium-voltage earthing switch products,this paper briefly describes and discusses related theory and industrial technical index such as electrical heating theory,electrical contact theory,electrodynamic theory,electric torque theory and so on.This paper systematically summarizes the influencing factors and scope to be considered in the research of earthing switch.This paper takes air insulated medium voltage earthing switch as the design object,expounds its design tasks,analyzes and calculates it.The content mainly includes the analysis and calculation of the conductor’s short-term temperature rise in the earthing circuit,the bounce of the blade system in the closing process,the stability of the blade system,the output force value of the energy storage spring,and the operating torque of the operating mechanism.In the analysis of electric force,the dynamic analysis method of electric force is adopted,and the concept of electric torque is introduced to solve the stability problem.Through analysis and calculation,a set of design methods suitable for medium voltage earthing switch is summarized.This design method is convenient and efficient,which can greatly shorten the development cycle of the product,reduce the development cost,improve the reliability of the product from the theoretical design level,has a positive practical guiding significance for the design of medium-voltage earthing switch,and provide a strong guarantee for the test of medium-voltage earthing switch.This paper takes air insulation medium voltage earthing switch as the test object,tests and analyzes the samples after the test,compares the difference between test data and theoretical design parameters,optimizes the design,improves the actual performance of the product,and improves the accuracy of earthing switch design.A set of test methods that are generally applicable to medium-voltage earthing switches are studied,which provides a strong guarantee for the accuracy and reliability of the design of medium-voltage earthing switches.