Adaptive Decoupling Between Receivers of Multi-Receiver Wireless Power Transfer System Using Variable Switched Capacitor
ABSTARCT :
With a fixed driving frequency, the number of Rx is not limited. It is analyzed that the quadrature phenomenon of the Tx and Rx currents can be used as a sign that the cross-coupling is fully compensated. A phase synchronization channel is established that shares power transfer coils. An MCU-free feedback loop is constructed in Rx to control the variable switched capacitor and finally realize adaptive cross-coupling compensation. A two-load experimental prototype was built to verify the theoretical analysis. Compared with the system without adaptive decoupling between Rxs, the measured system efficiency and output power of the proposed system were improved by 69% and 14.3 times, respectively.
EXISTING SYSTEM :
? It utilizes high-frequency electric fields to transfer electric power, which has three distinguishing advantages: negligible eddy-current loss, relatively low cost and weight, and excellent misalignment performance.
? Safety is always an important concern in the WPT technology; it exists in both IPT and CPT systems, and is becoming a major constraint in the practical applications.
? Although it has been proven that a CPT system can realize effective power transfer through a considerable distance, this process must be safe enough to be used for the general public.
? In CPT system, there are mainly three important safety concerns: high voltage stress on the plates, strong electric fields emissions to the surroundings, and foreign object influence.
DISADVANTAGE :
? Coupling efficiency peaks at close to 90% at a load resistance of 30 O. Although efficiency rolls off to around 36% at 1 kO, power delivered to the load resistance is very low and does not present heating problems to the system.
? The decrease in power delivery as shown in Figure 5 when load resistance increases is desirable as it helps to regulate the power during trickle charge.
? This technology can be applied to rugged electronics to enable the creation of hermetically sealed units, eliminating the problem of charging port contamination and corrosion.
PROPOSED SYSTEM :
• The proposed method is based on the concept of switch-mode gyrator emulating variable lossless inductors oriented to enable self-tunability in WPT receivers.
• This paper discusses the mistuning effect of parallel-compensated receivers, and thereof a novel dynamic frequency tuning method and related circuit topology and control is proposed and characterized in the system application.
• Therefore, this paper focuses on the discussion of mistuning issues in parallel-compensated WPT receivers in which the proposed dynamic tuning solution is dedicated for the same.
ADVANTAGE :
? The gaps between each turn of the transmitting coil are spaced in a manner to achieve uniform field distribution and consistent performance regardless of the placement of the receiving coil.
? However, shielding is beyond the scope of this paper and it is assumed that the system is adequately shielded from structures and materials that may significantly affect the system performance.
? The purpose of the analysis is to study the performance of the circuit as a generic switch and not as a specific decoupling mechanism.
? Transistor and diode models were obtained from the manufacturers to achieve accurate prediction of the performance of the fabricated circuit.
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