In a magnetic resonance coupling wireless power transmission system (WPT) with relay resonator coils
the cross coupling between nonadjacent coils may disturb the operation status of the system which often leads to reduction in the transmission power and efficiency. For the WPT system with single relay resonator (repeater)
by proceeding from the normalized equivalent circuit model
the effects of cross coupling between the transmitter coil and receiving one on the circuit current and the transmission power and efficiency of system are analyzed in detail. The conditions for judging whether the cross coupling is negligible or not are given. Meanwhile a convenient technique of inserting additional series reactance in circuits to make up for the cross coupling effect in the transmitter-repeater-receiver WPT system is proposed and its feasibility is verified via numerical simulation calculations and experiments. This work is supported by National Natural Science Foundation of China (No. 61461031).