Simultaneous Wireless Power And Information Transfer Technology Based On Phase Shift Modulation

Wireless power transmission technology has been widely used in mobile devices,electric vehicles,and implantable medical devices due to its advantages of easy portability and zero contact.However,most devices not only require electrical energy transmission,but also information transmission to achieve functions such as voltage feedback,state detection,and synchronization coordination.Therefore,simultaneous wireless power and information transfer technology has become a research hotspot in the wireless field.Electromagnetic waves can serve as both energy carriers and information media,so power and information transmission can be achieved through near-field magnetic coupling links without the need for additional communication modules.This thesis develops a channel multiplexing wireless power and information synchronization transmission system based on energy modulation scheme,which synchronizes power and information transmission through frequency control and phase shift modulation.Firstly,the working state of the system is divided through frequency control:when the system only requires wireless power supply,the working frequency of the phase-shifting full bridge inverter is equal to the resonance frequency f_p of the primary and secondary coils of the system,achieving efficient transmission of wireless power;When the system requires simultaneous wireless power and information transmission,the phase-shifting full bridge inverter uses f_p/3 as the low-frequency communication frequency to achieve data transmission by modulating the phase-shifting angle,and utilizes its third harmonic frequency f_p for efficient wireless power transmission.Implementing channel multiplexing on the same hardware device,achieving the transmission of low-frequency communication signals and efficient transmission of wireless power,has significant advantages in media conditions sensitive to communication frequency such as the ocean.Secondly,optimize some issues in the energy modulation topology.To address the issue of single carrier modulation having a significant impact on energy transmission in energy modulated wireless power and information synchronous transmission technology,the composition of the system current is changed by controlling the operating frequency of the full bridge inverter to achieve frequency division transmission of energy and information;Due to factors such as power transmission efficiency and channel bandwidth,the carrier is phase-shifted at the transmitting end and amplitude demodulated at the receiving end,implementing a frequency modulation amplitude modulation communication strategy.In theory,the selected working phase angle during communication only affects the amplitude component of the communication carrier to achieve decoding,without affecting the amplitude of the power transmission carrier;In order to achieve high signal-to-noise ratio data transmission,signal detection circuits were designed based on passive and active components to separate carriers at different frequencies.Finally,this article built a 25W near-field magnetic coupling experimental prototype.The experiment is conducted under operating conditions such as 3cm and 6cm information transmission distance,16V and 20V input voltage,10Ωand 100Ωoutput load,and 3cm and 6cm coil offset.The experimental results show that the system can still maintain 85%power transmission efficiency when transmitting data at a baud rate of 1k Hz.Successfully verified the feasibility of the simultaneous wireless power and information transfer system proposed in this article.