Serious influences on transmission properties will be exerted by the variations of systemic electricalparameters in magnetically-coupled resonant wireless power transmission（MCR-WPT） technology. So theinvestigation of relationships between them shows a material meaning in enhancing the transmission properties. Thecoil whose design is restricted by lots of factors is one of MCR-WPT system core components. How to capture theparameters which can achieve high efficiency and enough power has perplexed researchers for a long time. To thisend

load property is emphasized to study through the equivalent circuit theory. Then the conclusion that the optimalload resistances which make output power and transmission efficiency maximal simultaneously is not subsistent isextracted. The validity of theory analysis is verified through MATLAB. Influence regulations of systemic transmissionproperties coming from coil’s average radium and number of turns are investigated by MATLAB simulation. Theresults show that the output power first increases and then decreases as the turns increase when the system works innormal load. Based on the former work

a design for 60 Watt bulb is presented as an example. The designed systemcan achieve the efficiency of 94 percent when the distance is 0.5 m. Calculation results verify the practicability andreasonability of the coil’s parameters.