关键词: 无线电能传输, 谐振耦合, 负电阻, 输出功率

Abstract: Improving the wireless transmission power of resonant coupling power has always been one of the focuses in this field. A new method to improve the power of wireless transmission power was studied.A negative resistance in the primary side of the loose coupling transformer was introduced to increase the power of wireless transmission.The proposed method contributed to the voltage increase on the secondary side of the transformer by reducing the primary circuit resistance of the transformer to increase the primary current. The realization of the negative resistance was analyzed,and the power expression of the power wireless transmission system with negative resistance was obtained. The constraint condition of the system parameter selection was deduced according to the actual use limit of the negative resistance. The concept of the performance ratio was created to study the relationship between the output power growth and the additional losses caused by the introduction of negative resistance. The resonant coupling power wireless transmission test platform with a negative resistance was established.The comparison between negative resistances of different value showed that they can reduce the power wireless transmission system circuit impedance, increase the circuit current, and improve the system output power. Besides,a reasonable choice of parameters that make up the negative resistance can effectively improve the performance ratio.

Key words: wireless power transmission (WPT), resonant coupling, negative resistance, output power