Analysis and Suppression of Common Mode Noise for Underwater IPT Systems With Parasitic Capacitances

The high conductivity of seawater significantly intensifies the parasitic capacitances in the inductive power transfer (IPT) system which exacerbates the common-mode (CM) interference. This special phenomenon critically affects the reliability of underwater IPT systems. To address this issue, this paper models the parasitic capacitance of components in IPT systems when immersed in seawater and presents the measurement methods for parasitic capacitance. Subsequently, a refined circuit topological model based on LCC-S is built to analyzed the CM crosstalk pathways and the magnitude in different medium. Additionally, a CM noise suppression method based on balanced impedance is derived through mathematical formulation. An experimental platform is constructed with an output power of 1 kW, which is used to validate the feasibility of the proposed design against a conventional LCC-S network.