Resonant Capacitor Switching in Wireless Power Receivers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In two-way wireless charging systems, electromagnetic interference (EMI) and efficiency issues arise due to shielding challenges, mutual inductance changes, and frequency variations, particularly when multiple receivers are involved.
Innovation Solution
A method and circuit for adjusting the resonant capacitor value in a wireless power reception apparatus to maintain optimal system efficiency by controlling the resonant frequency, using a resonant circuit with multiple paths and gates to manage capacitance and inductance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a fixed resonant frequency is used in the wireless power reception apparatus, then the circuit design is simple, but the system efficiency decreases when transmission frequency varies or when multiple receivers are present
Solution Approach 1:
The patent implements a dynamic resonant frequency adjustment mechanism where the resonant frequency of the reception apparatus is continuously adapted to match the transmission frequency. This is achieved through frequency tuning circuits and control mechanisms that modify the resonant parameters in real-time, ensuring optimal power transfer efficiency regardless of frequency variations or multiple receiver scenarios.
Solution Approach 2:
The patent changes the resonant frequency parameter of the reception apparatus dynamically. By adjusting the resonant frequency to coincide with the transmission frequency, the system maintains high efficiency. This involves modifying electrical parameters such as inductance and capacitance values in the resonant circuit to achieve frequency matching under different operating conditions.
2Object-affected harmful factors
If spread spectrum transmission is used to reduce EMI, then electromagnetic interference emissions are reduced, but system efficiency decreases due to transmission frequency variations
Solution Approach 1:
The patent implements a feedback mechanism where the reception apparatus detects the actual transmission frequency and adjusts its resonant frequency accordingly. This closed-loop control ensures that even when spread spectrum techniques cause frequency variations, the reception apparatus maintains optimal resonance and efficiency by continuously adapting to the transmitted frequency.
3Power
If reception coil and transmission coil are placed closer to increase power transfer, then wireless power transfer capability is improved, but mutual inductance changes cause resonant frequency shift and efficiency decrease
Solution Approach 1:
The patent employs dynamic frequency adjustment to compensate for mutual inductance changes. When the distance between transmission and reception coils changes, the resonant frequency of the reception apparatus is automatically adjusted to maintain optimal power transfer, preventing efficiency loss due to frequency mismatch.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach maximizes wireless power transmission efficiency by dynamically adjusting the resonant frequency to match transmission frequencies, minimizing operation losses and maintaining efficiency across varying environments.
Implementation Method 1
a wireless power transmission system is optimized for a single receiver having a reactance (LC) resonant frequency equal to a transmission frequency
Implementation Method 2
a mutual inductance (coupling coefficient) between reception coils increases
Data Source
AI summary
Provided is a wireless power reception apparatus. The wireless power reception apparatus includes a resonant circuit including a first path and a second path, the first path including a first capacitor and a first gate connected in series, and the second path being connected in parallel with the first path and including a second capacitor and a second gate connected in series and a reception coil connected to the resonant circuit, configured to wirelessly receive power based on a capacitance of the resonant circuit, and to generate power according to the wirelessly received power, wherein the resonant circuit is configured to determine a gate driving signal to operate the first gate and the second gate and wherein the capacitance of the resonant circuit is determined according to the gate driving signal.