PCB Planar Transformer Structure for Low Leakage Welding Power
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional high-frequency transformers in welding-type power supplies suffer from leakage inductance, which reduces output, causes overheating, and is detrimental to transistor switching circuits.
Innovation Solution
The use of low-leakage planar transformers, which consist of primary and secondary winding boards made of layers of substrate and printed conductive strips, are designed to minimize parasitic inductance and capacitance, and are constructed to operate effectively at high frequencies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional high-frequency transformers are used in welding-type power supplies, then voltage transformation function is achieved, but leakage inductance increases causing reduced output, overheating, and detrimental effects on transistor switching circuits
Solution Approach 1:
The patent transitions from conventional three-dimensional wound wire windings to a two-dimensional planar winding structure printed on substrate boards. This dimensional change allows for optimized magnetic coupling between primary and secondary windings, significantly reducing leakage inductance while maintaining the voltage transformation function. The planar configuration enables better control over winding geometry and spacing, directly addressing the leakage inductance problem.
Solution Approach 2:
The patent replaces traditional mechanical wire-winding processes with printed conductive traces on substrate boards. This substitution eliminates the variability and inefficiency of manual or automated wire winding, providing precise control over winding parameters and enabling consistent low leakage inductance performance. The printed circuit board technology allows for exact replication of winding patterns and optimized magnetic coupling.
2Temperature
If conventional transformers are used, then voltage step-down is achieved, but overheating occurs due to leakage inductance losses
Solution Approach 1:
The planar winding structure enables optimized spatial arrangement of primary and secondary windings on the same plane, improving magnetic coupling efficiency. This dimensional change reduces the magnetic path length and minimizes flux leakage, thereby reducing leakage inductance losses and the associated overheating problems in welding power supplies.
Solution Approach 2:
The patent changes the geometric parameters of the windings by using printed traces with controlled width, spacing, and pattern on substrate boards. By optimizing these parameters, the magnetic coupling between windings is enhanced, leakage inductance is reduced, and energy losses are minimized, preventing overheating while maintaining efficient voltage transformation.
3Power
If conventional transformers are used, then voltage transformation is achieved, but output power is reduced due to leakage inductance
Solution Approach 1:
The transition to planar windings on substrate boards enables optimized magnetic coupling and reduced leakage inductance, which directly improves output power capability. The two-dimensional configuration allows for better control over winding geometry, ensuring maximum magnetic flux linkage and minimizing energy stored in leakage inductance, thereby enhancing the power delivery capability of the welding power supply.
Solution Approach 2:
Replacing mechanical wire winding with printed conductive traces provides precise control over winding parameters, ensuring optimal magnetic coupling. This substitution eliminates the variability inherent in mechanical winding processes, delivering consistent low leakage inductance and maximizing output power for welding applications.
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 low-leakage planar transformers achieve reduced leakage inductance, enhanced cooling, and improved operational efficiency at high frequencies, allowing for higher average and peak loads while maintaining a safe operating temperature.
Implementation Method 1
the primary voltage, or input voltage, enters the primary winding and creates a magnetic field that induces voltage in the secondary winding
Data Source
AI summary
Disclosed example planar transformers include: a magnetic core; a first primary winding board secured to the magnetic core; a first secondary winding board secured to the magnetic core, wherein each of the first primary winding board and the first secondary winding board comprise: a first printed winding on a first layer of a circuit board; first and second mounting tabs on the first layer of the circuit board or a third layer of the circuit board, and coupled to the first printed winding; a second printed winding on a second layer of the circuit board; and third and fourth mounting tabs on the second layer of the circuit board or a fourth layer of the circuit board, and coupled to the second printed winding; and a first spacer to position the first primary winding board a predetermined distance from the first secondary winding board.