Conductive Noise Suppressor Using Magnetic Coupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing power converters generate conductive common mode noise due to switching operations, which worsens with high-frequency components due to phase differences caused by amplification circuits, necessitating a method to suppress this noise effectively.
Innovation Solution
A conductive noise suppressor system that includes a current detector, a noise suppressor coil magnetically coupled to a power line coil, and a current supplier to induce a current in the coupling coil, altering the power line impedance and reducing common mode noise, while minimizing phase differences and frequency-dependent noise worsening.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a current flows through a coil inserted in series with a power line to suppress conductive common mode noise, then the noise suppression effect is improved, but the high-frequency noise is worsened due to phase difference caused by delay of the amplifying circuit
Solution Approach 1:
The patent introduces a coupling coil as an intermediary element that magnetically couples to the series coil. This coupling coil receives the suppressor current through magnetic induction rather than direct electrical connection, thereby eliminating the phase delay caused by amplifying circuit delays while still achieving the desired noise suppression effect through the induced current in the coupling coil.
Solution Approach 2:
The patent replaces the direct electrical connection and amplifying circuit system with a magnetic coupling system. Instead of using an amplifying circuit to drive the series coil directly (electrical system), the invention uses magnetic induction through a coupling coil to generate the suppressor current (magnetic field system), thereby avoiding the phase delay inherent in electrical amplifying circuits.
2Object-affected harmful factors
If an amplifying circuit is used to drive the series coil, then the noise suppression effect is improved, but phase difference occurs due to circuit delay which worsens high-frequency noise
Solution Approach 1:
The coupling coil serves as a mediator that transfers the control signal from the detector to the series coil through magnetic coupling rather than direct electrical connection. This intermediary magnetic field transmission eliminates the phase delay caused by amplifying circuit electronics, maintaining phase accuracy while still enabling effective noise suppression.
Solution Approach 2:
The invention substitutes the electronic amplifying circuit system with a magnetic induction system. The detector's output signal induces current in the coupling coil through magnetic coupling, replacing the need for electronic amplification and eliminating the associated phase delays, thereby improving phase accuracy for high-frequency noise suppression.
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
The system effectively suppresses common mode noise by inducing a current in the coupling coil, reducing noise currents and impedance changes, thereby improving noise suppression across frequencies and preventing noise worsening due to phase differences.
Implementation Method 1
a noise suppressor configured to include a coil connected to the power line in series and a coupling coil magnetically connected to the coil
Data Source
AI summary
A conductive noise suppressor for suppressing worsening of noise due to the frequency of conductive common mode noise is suppressed is provided in an embodiment of the disclosure. The suppressor includes a first coil part for detecting a noise current in a common mode flowing through a power supply line for supplying an alternating current, coils serially inserted on the power supply line, a second coil part including a coupling coil magnetically coupled to the coils and a current supplier for supplying a noise current detected by the first coil part and a current set for a voltage generated across the coupling coil to the coupling coil.