Abstract
The WPT system for logistic robots has the problems of large fluctuation of charging power and low efficiency due to the change of its position. Based on the principle of parity time symmetry, an omnidirectional and efficient wireless power transfer system for logistic robots is proposed. Firstly, the coupling coefficient of two planar spiral coils in different relative positions in space are studied. Then, a time-varying coupled-mode model of the WPT system based on the offset angle of the receiver coil is established, and its working principle and characteristics are analyzed. As long as the coupling coefficient satisfies certain conditions, the output power and efficiency of the system are always keeping constant. Finally, the proposed model is experimentally verified. The measured results show that the WPT system proposed can realize stable 150W power transfer with constant transmitting efficiency of more than 90% for a logistic robot within a confined three-dimensional space around the charging station, which are provided to further verify the correctness of theoretical analysis.
Highlights
In recent years, due to its high degree of automation and strong adaptability, logistic robots play an increasingly important role in automation and intelligent industrial production activities, and widely used in automotive, electronics, e-commerce and other fields [1]–[3]
Logistic robots are mainly charged by cable, it has the disadvantages of large battery consumption, short cruising range and long charging time [4], and the use of cable charging greatly limits the charging position of the logistics robot, which has been unable to meet the characteristics of the fully automated operation of the logistics robot
This paper proposes an omnidirectional and efficient wireless power transfer system for logistic robots based on the principle of parity time symmetry
Summary
Due to its high degree of automation and strong adaptability, logistic robots play an increasingly important role in automation and intelligent industrial production activities, and widely used in automotive, electronics, e-commerce and other fields [1]–[3]. A time-varying coupled-mode model of WPT system with PT symmetry principle is proposed based on the direction offset angle of the receiver coil, and is applied to the distributed wireless charging system of logistic robots. In the actual scene of WPT system for logistic robots, the two typical coil positions of axial movement with an offset of 0◦ and radial movement with an offset of 90◦ are selected, and the variation law of coupling coefficient between coils is studied, as shown, including the comparison between calculated, simulated and actual measured results It can be seen from Fig. that as the relative positions of the FIGURE 4. The direction change amount of coil’s position is added to the static system in which the coil is axially symmetrically placed, so that a time-varying coupled-mode model of WPT system based on the offset angle of the receiver coil is proposed. Ignoring the second-order small quantity, the coupled mode equation of the system is obtained dty
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
