Synchronous rectification using mosfet

AC TO DC CONVERSION USING MOSFETS

Table of Contents

Introduction

Rectification

Types of Rectification

MOSFET Rectification

Comparison

Advantages

Simulation

1

AC TO DC CONVERSION

convert alternating current (AC) to (DC).

Used for almost all appliances.

2

Passive & ActiveAC-DC

Conversion

Passive rectification.

Active rectification.

3

Half-wave Rectifier

Rectifies only half cycle of the waveform.

consist a step down transformer, a diode and a load resistance.

4

Full Wave Bridge Rectifier

Full Wave Bridge Rectifier circuit four diodes are used.

Conducts for both positive and negative half cycles and gives .

5

MOSFET Rectification

Four MOSFETs in a bridge configuration ;

P-type and N-type MOSFETs.

Act as a switch with a small on-resistance

Threshold voltage

6

Working of MOSFET rectifier

P-M1 and N-M2 turn on during the positive half-cycle of the input voltage.

The current follows the path starting from Vin over P-M1, RLoad, N-M2, and reaches the starting point Vin again.

During the negative half-cycle, P-M2 and N-M1 turn ON.

7

MOSFET over Diodes

High power losses .

Thermal dissipation.

Coast

Small RDON

8

Power loss comparison

Comparison

9

Get rid of transformer or boost circuits

Step-up transformer.

Decrease turns ratio.

10

Heat sink requirement

Avoid expensive and bulky heat sinks.

11

Limitations of MOSFETS

Loss during switching transition .

Average switching power loss represented by:

12

Overall Benefits of

Improved efficiency.

No thermal management.

Design is reduced.

Supports higher frequencies.

13

Simulink SimulationUsing MOSFET

14

Simulation Result

15

Simulink SimulationUsing Diode

16

Simulation Result

17

PROTEUS SimulationUsing MOSFET

18

Universal Bridge in SIMULINK

THANKS FOR YOUR TIME