The application of wireless power transmission (WPT) technology to the V2G field of electric vehicles has both important research value and practical value. Aiming at the problem of designing the compensation network parameters of the WPT system, this paper establishes the mathematical model of the WPT system utilizing the LCC compensation network, and derives the expression of the current RMS value of the flow compensation network component. By analyzing the current RMS expression of the compensated network component, it can be known that for a certain transmission power demand P0, if the value of the secondary compensation capacitor Cs is smaller, the RMS value of the fundamental wave current flowing through the secondary compensation component is smaller. The RMS value of the fundamental current of the primary compensation component is larger. The smaller the value of the secondary side compensation capacitor Cs is, the smaller the effective value of the fundamental wave current flowing through the secondary compensation element is, which is beneficial to reduce the volume of the secondary compensation element. The reduction of compensation component volume is an important part of the volume control of electric vehicle wireless charging system. The balance between the current stress of the network component in system compensates is the premise of reducing the overall component volume. Therefore, this paper proposes the design method of small-volume secondary compensation network parameters for the purpose of balance stress level and current decrease. Also, the correctness of the relevant theory is verified by simulation.