使用多發射器實現無線供電網路之調變分析

Abstract

無線供電網路可應用於智慧工廠以及智慧家居，其目的為無線充電以及資料傳輸，然而傳輸效率會隨著接收器的位置以及角度的影響而改變，本論文使用多發射器以弱磁耦合及電磁輻射耦合方式討論任意方向之無線功率傳輸，並使用調變方式改善傳輸效率，使接收器在任何放置角度下，均能接收到穩定的功率。 本論文於前半段會先介紹無線功率傳輸理論，包含磁耦合以及電磁輻射之原理，傳輸過程中，為了使發射器與接收器在任意方向上皆能收到一定的功率，使傳輸效率不會受到接收端之任意方向角度改變而受到影響，因此，本論文後半段提出多個發射器之架構，建立等效電路模型，分析發射器與接收器之間耦合對於傳輸效率影響，藉由調整多發射器之間的相位差、頻率差等調變技術，以降低接收器任意方向旋轉對傳輸效率影響。最後使用RFID進行量測，驗證接收功率不會受到接收器之任意方向角度改變而影響，並確保發射器與接收器可接收到一定的功率，達成穩定之供電效能。

In this thesis, wireless power transmission system using multiple transmitters will be discussed. Wireless power grid is applied in the warehouse or household to build a energy management system. However, the power transfer efficiency depends on the orientation of the receiver. The receiver may be angularly and laterally misaligned that may cause the decrease of the power transfer efficiency. To solve this problem, we proposed multiple transmitters with phase, amplitude and frequency modulation to make the power transfer efficiency more stable. The first part of the thesis presents the wireless power transmission principles including the weak magnetic induction and electromagnetic radiation. In order to solve the orientation problem. We propose the multiple transmitters structure. Therefore, the second part of this thesis shows the design of multiple transmitters structure. We establish an equivalent circuit model and show the results of the power transfer efficiency. By adjusting the phase difference and frequency difference between transmitters, we can solve the orientation problem. Finally, we measure the received power under different rotation angle to ensure the received power is stable. This method can be used to achieve the stable power performance.