Characterizations of High Frequency Planar Transformer With a Novel Comb-Shaped Shield
Author(s)
Lu, J
Dawson, F
Griffith University Author(s)
Year published
2011
Metadata
Show full item recordAbstract
This paper presents a newly developed comb-shaped Faraday shield for high frequency (HF) planar transformers. High power density and small size planar transformers are widely used in switching mode power supplies (SMPS) as magnetically coupled devices. However, the intra-winding capacitance couples HF noise from the primary winding to the secondary winding. The coupling capacitance can cause serious common mode problems, and thus the design may not be electromagnetically compatible with the surrounding environment. The tradeoff between the leakage inductance and the coupling capacitance becomes problematic for high ...
View more >This paper presents a newly developed comb-shaped Faraday shield for high frequency (HF) planar transformers. High power density and small size planar transformers are widely used in switching mode power supplies (SMPS) as magnetically coupled devices. However, the intra-winding capacitance couples HF noise from the primary winding to the secondary winding. The coupling capacitance can cause serious common mode problems, and thus the design may not be electromagnetically compatible with the surrounding environment. The tradeoff between the leakage inductance and the coupling capacitance becomes problematic for high frequency applications. The coupling capacitance can be reduced either by increasing the separation distance between the primary and the secondary windings or by inserting a conventional Faraday shield. The former may cause the leakage inductance to increase and further increase the insertion losses, whereas the latter would result in a serious demagnetizing problem in a HF planar transformer. These problems can be resolved by using a novel comb-shaped Faraday shield.
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View more >This paper presents a newly developed comb-shaped Faraday shield for high frequency (HF) planar transformers. High power density and small size planar transformers are widely used in switching mode power supplies (SMPS) as magnetically coupled devices. However, the intra-winding capacitance couples HF noise from the primary winding to the secondary winding. The coupling capacitance can cause serious common mode problems, and thus the design may not be electromagnetically compatible with the surrounding environment. The tradeoff between the leakage inductance and the coupling capacitance becomes problematic for high frequency applications. The coupling capacitance can be reduced either by increasing the separation distance between the primary and the secondary windings or by inserting a conventional Faraday shield. The former may cause the leakage inductance to increase and further increase the insertion losses, whereas the latter would result in a serious demagnetizing problem in a HF planar transformer. These problems can be resolved by using a novel comb-shaped Faraday shield.
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Journal Title
IEEE Transactions on Magnetics
Volume
47
Issue
10
Subject
Physical sciences
Engineering
Electrical energy generation (incl. renewables, excl. photovoltaics)