Non-contact Power Supply Constant Voltage Feedback Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Non-contact power supply devices employing the SPL method face challenges in maintaining constant voltage output and stability due to variations in the coupling coefficient between transmission and reception coils, leading to resonance frequency fluctuations and increased energy loss.
Innovation Solution
The device incorporates a power transmission device with an adjustable switching frequency and voltage for the transmission coil, and a power reception device with a resonance circuit including a reception coil, a parallel resonance capacitor, and a series-connected coil, along with voltage and current detection circuits to maintain constant voltage output by controlling the switching frequency and voltage based on measured values.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the SPL method is employed to improve power transmission efficiency, then power factor is improved and transmission efficiency increases, but resonance frequency variation due to coupling coefficient change becomes problematic
Solution Approach 1:
The patent implements a feedback control mechanism where the controller detects the output voltage from the resonance circuit and adjusts the switching frequency and voltage of the power supply circuit based on this detection. This closed-loop feedback system maintains constant voltage output despite variations in coupling coefficient, resolving the contradiction between improving transmission efficiency and maintaining resonance frequency stability.
Solution Approach 2:
The patent employs dynamic adjustment of the switching frequency and voltage in the power supply circuit based on real-time detection of output voltage and coupling coefficient changes. This dynamic control allows the system to adapt to varying operating conditions while maintaining stable constant voltage output, addressing the resonance frequency stability issue while preserving the efficiency benefits of the SPL method.
2Adaptability or versatility
If the coupling coefficient between transmission and reception coils is not constant, then adaptability to different usage conditions is improved, but resonance frequency variation increases
Solution Approach 1:
The feedback control mechanism continuously monitors the output voltage and coupling coefficient, and the controller adjusts the switching frequency and voltage accordingly. This allows the system to adapt to different usage conditions and coupling coefficients while maintaining stable resonance frequency and constant voltage output, resolving the contradiction between adaptability and stability.
Solution Approach 2:
The patent changes the parameters of the power supply circuit (switching frequency and voltage) based on detected coupling coefficient variations. By dynamically adjusting these parameters, the system maintains optimal operation across different usage conditions while suppressing resonance frequency variation, achieving both adaptability and stability.
3Adaptability or versatility
If constant voltage output operation is implemented, then compatibility with electronic appliances is improved, but control complexity increases compared to constant current output
Solution Approach 1:
The patent uses feedback control where the controller detects output voltage and adjusts the power supply circuit's switching frequency and voltage to maintain constant voltage output. This feedback mechanism, while adding control complexity, enables constant voltage operation that is compatible with electronic appliances, resolving the contradiction between compatibility and control complexity by making the complexity necessary for achieving the desired functionality.
Solution Approach 2:
The patent replaces the traditional constant current output mechanism with an electronically controlled constant voltage system using switching frequency and voltage adjustment. This substitution enables direct compatibility with electronic appliances that require constant voltage, accepting the increased control complexity as a necessary trade-off for improved versatility.
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 configuration effectively suppresses resonance frequency variations, ensures constant voltage output, and reduces energy loss by adjusting the switching frequency and voltage to maintain optimal operation despite changes in the coupling coefficient and load resistance.
Implementation Method 1
a method of supplying power by electromagnetic induction is known
Implementation Method 2
since the resonance circuit constituted by the reception coil and the capacitor on the power reception side causes parallel resonance
Data Source
AI summary
A power transmission device 2 for a non-contact power supply device 1 has a transmission coil 14 and a power supply circuit 10 that supplies, to the transmission coil 14, AC power having a switching frequency at which the transmission coil 14 does not resonate. In addition, a power reception device 3 for the non-contact power supply device 1 has: a resonance circuit 20 that has a reception coil 21 and a resonance capacitor 22 resonating in parallel and a first coil 23 connected in series or parallel to the reception coil 21; and a coil 23 connected in series to the reception coil 21.