High side flyback circuit configuration for CM noise cancellation
- PDF / 1,721,349 Bytes
- 10 Pages / 595.276 x 790.866 pts Page_size
- 50 Downloads / 214 Views
ORIGINAL ARTICLE
High side flyback circuit configuration for CM noise cancellation Kaining Fu1 · Wei Chen1 Received: 28 January 2020 / Revised: 29 May 2020 / Accepted: 1 June 2020 © The Korean Institute of Power Electronics 2020
Abstract Flyback topologies have advantages in terms of low cost, fewer electrical components, and simple circuit design. Semiconductor devices in the primary and secondary sides are regarded as major EMI noise sources in EMI propagation paths. However, the same transformers under different circuit configurations can bring different noise cancellation effects due to a change of the electric potential distribution in transformer windings as well as the phases of the EMI noise sources in the primary and secondary sides. In this paper, a CM noise cancellation mechanism is investigated. In addition, a flyback topology with high side gate driving in the primary side is proposed to form a CM noise cancellation mechanism. Based on the proposed flyback topology, the capacitor compensation cancellation technique can be applied to lower the electromagnetic interference (EMI) noise level of the designed converter. Finally, the experimental noise spectrums are used to verify the effectiveness of the proposed flyback circuit configuration scheme. Keywords Common-mode (CM) · EMI · Transformer · Capacitor · High side gate driving
1 Introduction Flyback topologies have been widely used in consumer electronics. For switch mode power supply (SMPS) designers, thermal and electromagnetic compatibility (EMC) design procedures are critical for high-quality power products. The international special committee on radio interference (CISPR) published some relevant electromagnetic interference (EMI) standards for EMI measurement methods and EMI limitation lines (EN55032 class B) [1]. EMI filters are usually used to attenuate EMI noise, and a large volume of magnetic components and X capacitors can lower the power density of an entire converter. Furthermore, near field coupling exists in tiny printed circuit boards (PCB) due to the mutual electric coupling and magnetic coupling among EMI filter components [2]. There are two main CM noise propagation paths [3]. One is the ground capacitance between the high dv/dt node in the primary side and the chassis ground. This part of CM noise can circulate internally by attaching a heat sink to the primary ground [4]. However, with the development of semiconductor device manufacturing * Kaining Fu [email protected] 1
College of Electrical Engineering and Automation, Fuzhou University, Fuzhou, China
techniques and the size reduction tendency of power converters, more and more semiconductor devices have become surface mounted devices (SMD). Then a heat sink cannot be installed with upper semiconductor devices. In this case, the CM noise cannot be eliminated by the above mentioned method. The second propagation path is the interwinding capacitance of the transformer caused by the electric coupling between adjacent primary and secondary winding layers. The primary MOSFE
Data Loading...
