Study on Boundary Element Method Applied in Transient Huge Current Measurement

Abstract

With the rising of the power system voltage level, the traditional electromagnetic current transformer can no longer meet the power system transient current measurement requirements. Magnetic Array transient current measurement method was one of the major development directions of the power system transient huge current measurement. The paper establishes the relationship between magnetic fields and currents using the principle of superposition, according to the rule that current generate the magnetic field, and chooses the boundary element method with surface impedance concept as the method to solve the inverse problem of transient huge current. The paper also states that the inverse problem of the eddy current generated by the transient current in certain conditions may achieve by using a new boundary element equations, that is, to introduce the time-domain surface impedance boundary condition, and change the integral equation into a constant form. The integral equation is needed to be solved only once in a given topology. The model is established in ANSYS, and the simulation experiments show the efficiency and correctness of the method.