Study on Contact Resistance Dynamic Characteristics of Space Electromagnetic Relay

Contact resistance is an important parameter that directly reflects relay performance and it is also a basic datum to evaluate relay reliability. Based on theories of electromagnetic field, kinetics, contact force and electric contact, a full simulation analysis scheme of relay dynamic characteristics was presented by using the method of coupling finite element analysis and kinetic computation in the paper. Contact resistance dynamic characteristics of pick-up and drop-out process were also obtained. For the break-off contact, it was found that the break-off speed was fast during the pick-up process, but there was contact bounce during the drop-out process. For the close-up contact, its stabilization time was long during both the pick-up and drop-out process, so it would affect the electrical contact performance and lifetime of the relay. In addition, the change rate of the contact resistance was large during the operating moment, thus it would affect the performance of conterminous electric circuit.