HIGH-DENSITY EMI FILTER DESIGN FOR DC-FEDMOTOR DRIVES


  HIGH-DENSITY EMI FILTER DESIGN FOR DC-FEDMOTOR DRIVES.ppt (Size: 666.5 KB / Downloads: 0)

INTRODUCTION

Electromagnetic interference (EMI) is one of the major design challenges in motor drive systems, especially in applications where stringent standards need to be followed. EMI noise is usually defined as common-mode (CM) and differential-mode (DM) noise. CM noise is defined as the noise flows between the power circuit and the ground, while DM noise is defined as the current following the same path as the power delivery.
During the last decade, many papers have proposed procedures for designing EMI filter. A step-by-step method is used in to obtain the required attenuation, corner frequency, and the filter parameters. Unfortunately, this method only fulfills the low-frequency (LF) requirement and suggests a trial-and-error process for high frequencies (HFs).


EXISTING SYSTEM

A step-by-step method is used to obtain the required attenuation, corner frequency, and the filter parameters. Unfortunately, this method only fulfills the low-frequency (LF) requirement and suggests a trial-and-error process for high frequencies (HFs). The unpredictable behavior at HFs is mainly due to the parasitic of the filter components such as the CM choke or the coupling between components, as well as their interaction with the noise source. These HF effects are usually worse when the size is reduced and the components are close together.

DISADVANTAGES OF EXISTING SYSTEMS

Only fulfills the low-frequency (LF) requirement and suggests a trial-and-error process for high frequencies (HFs).
An inadequate filter design can result in poor performance, high cost, and a larger size than required.


BLOCK DIAGRAM EXPLANATION


The dc supply is fed into LISN by which LISN is used for the measurement of the EMI filter.
LISN measures the EMI filter value and then it takes the required supply from dc supply.
EMI filter reduces both the common mode and differential mode noise and the signal is passed to the inverter.
The inverter is controlled by a external control signal circuit .
Then the signal from the inverter is fed to the ac motor.



ADVANTAGES

Reduced filter size and good filtering performance when compared with standard filters at both low and high frequencies.


APPLICATIONS


Personal Computers
Motor drives

HARDWARE USED

EMI Filter
Inverter
Induction Motor