Aiming at the shortcomings of large starting current and small output power for induction energy acquisition methods of conventional current transformers,an on-line energy acquisition method for transmission lines based on impedance matching is proposed in this paper.In this method,parallel resonance is generated by matching the secondary winding of the open gap magnetic core with its excitation impedance,thus the equivalent impedance of the damping branch of the magnetic core is increased.So that the load can get more electric energy by more current separated by the other branch.The energy ac...