News

Home  -  News  -  Industry News

Common mode line filter inductance

source:Industry News Popular:adapter release time:2021-05-11 09:12:04 Article author:sznbone

  The figure shows a typical balanced line filter, which is used in offline chargers to limit conducted RFI noise. It can be seen from the figure that two independent inductors L1(a) and L1(b) are wound on the same magnetic core to form a dual-winding common-mode line filter. It can also be seen from the figure that the inductor L2 is one Single winding series inductor.

Common mode line filter inductance(图1)

  The figure shows two typical dual-winding common-mode filter inductors.

  The common mode filter inductor has two independent windings with the same number of turns. The two windings are connected to the circuit in an inverted manner, so that the series-connected power frequency current can pass through. Therefore, the magnetic field generated by the normal series AC (or even DC) charger current will cancel to zero.

  When the two windings are connected in anti-phase and pass a series current, the inductance presented is only the leakage inductance between them. Therefore, the low-frequency line current will not be able to saturate the magnetic core, so materials with high permeability can be used without introducing an air gap in the magnetic core, so that a larger inductance can be obtained with a smaller number of winding turns.

  However, for common mode noise (noise current or voltage to ground generated at both ends of the line at the same time), the two windings are parallel and in phase, and exhibit a high inductance under common mode current. Therefore, in order to prevent any effective common mode interference current from being conducted to the input charger circuit, common mode noise current can be introduced into the ground from the bypass circuit through capacitors C1 and C2.


Read recommendations:

Amplifier + power supply

30W desktop

Single power supply

What are the advantages of sharing mobile power!adapter 18w factory

laptop adapter cooling

Previous:What are the functions of the resistors and capacitors on both sides of the crystal oscillator? Back to list Next:Maintenance Methods for 12V Switching Power Supply

The latest article

Related Products

The latest article

What are the types of mobile phone chargers and their functions?

2022-05-21

Advantages of switching power adapters

2022-05-21

Five core functions that the power adapter can achieve.adapter manufacture

2022-05-20

Analysis of the importance of power adapters for notebooks.adapter Processor

2022-05-20

Details of switching power supply in maintenance

2022-05-19

Understand the precautions of the power adapter and be an expert in electricity safety

2022-05-19

This is how the EMC interference of the switching power supply is generated.adapter wholesaler

2022-05-18

The relationship between the nominal voltage and current of the power adapter.power adapter price

2022-05-18

Five basic functions of notebook power adapters.adapter wholesaler

2022-05-17

Lightning surge immunity test method.power adapter price

2022-05-17

Switching power supply ripple source and control

2022-05-16

Level 6 energy efficiency standard power adapter T series

2022-05-16

Children sleeping with pacifiers are prone to tooth decay

2022-05-16

Six methods to deal with the heating problem of switching power supply transformer

2022-05-14

The principle of flyback switching power supply

2022-05-14

Types of thermal protection for power adapters.adjustable power adapter

2022-05-13

Summary of common faults of LED switching power supply

2022-05-13

The power transistor should be used like this in the power adapter

2022-05-12

4 modulation methods of switching power supply

2022-05-12

Some little knowledge about switching power supply

2022-05-11

Laptop Power Adapter Troubleshooting Steps

2022-05-11

9 classification methods of switching power supply

2022-05-10

Advantages and disadvantages of switching power supply current mode

2022-05-10

Advantages and disadvantages of switching power supply current mode

2022-05-09

9 classification methods of switching power supply

2022-05-09

Characteristics and working methods of PFC regulated switching power supply

2022-05-07

Six maintenance rules for drone lithium batteries.manual charger power adapter

2022-05-07

Reasons for Inrush Current in Switching Power Supply Design.adjustable power adapter

2022-05-06

The optimal solution of drone power management solution!12w acdc power adapter

2022-05-06

Characteristics of Switching Power Adapter Transient Loads

2022-05-05