FUZZY LOGIC CONTROLLER ON DC/DC BOOST CONVERTER

PRESENTED by -RAGHVENDRA KUMAR PANDITB.TECH 3RD YEAR (6TH SEM)BRANCH –EESECTION –A2 ENROLL NO. –MUR1301260

Submitted to-MR.V SIVA

brahmaiyah rama

MEWAR UNIVERSITYTopic –Fuzzy Logic Controller on DC/DC Boost Converter

Department of Electrical Engineering

ABSTRACT :-This paper describes the design of a fuzzy logic controller using voltage output as feedback for improving the dynamic performance of boost dc-dc converter by using MATLAB@Simulink software. The objective of this proposed methodology is to develop fuzzy logic controller on control boost dc-dc converter using MATLAB@Simulink software. The fuzzy logic controller has been implemented to the system by developing fuzzy logic control algorithm. The design and calculation of the components especially for the inductor has been done to the converter operates in continuous conduction mode. The evaluation of the output has been carried out and compared by software simulation using MATLAB software between the open loop and closed loop circuit. The simulation results are shown that voltage output is to be control in steady state condition for boost dc-dc converter by using this methodology.


INTRODUCTION:-Nowadays, the control systems for many

power electronic appliances have been increasing widely. Crucial with these demands, many researchers or designers have been struggling to find the most economic and reliable controller to meet these demands. The idea to have a control system in dc-dc converter is to ensure desired voltage output can be produced efficiently as compared to open loop system.


WHAT IS FUZZY LOGIC:- The idea of fuzzy logic was first advanced by Dr. Lotfi

Zadeh of the University of California at Berkeley in the 1960s. Dr. Zadeh was working on the problem of computer understanding of natural language. Natural language (like most other activities in life and indeed the universe) is not easily translated into the absolute terms of 0 and 1.

Fuzzy logic is an approach to computing based on "degrees of truth" rather than the usual "true or false" (1 or 0) Boolean logic on which the modern computer is based.

Fuzzy logic seems closer to the way our brains work.


BOOST DC/DC CONVERTER:- Output voltage always higher

than the input voltage

When the switch is ON:-

Diode is reversed biased

output circuit is thus isolated

inductor is charged.

When the switch is OFF:

The output stage received

energy from the inductor as

well as from the input.

Filter capacitor is very large to

ensure constant output voltage

Vd

L D

CS

+ vL

iL

+vo

Vd

D

CS

+ vL -

iL

+vo-


SWITCHING DEVICE:- In this MOSFET is used as

switching device

It is voltage controlled

device and also it requires

small input current

Switching speed is very

high

It operates in nano sec’s


Boost converter for MATLAB:- Department of Electrical Engineering

Block Parameters For Converter:- Department of Electrical Engineering

Block Parameters For Converter:-


Block Parameters For Converter:-


MATLAB Simulation Figure:-

Fig. Output voltage for Boost converter


ADVANTAGES:- Only one switch

High efficiency

Unidirectional output current

Provides one polarity output voltage

Low cost

Easy to analyze

Easy to understand

Simple circuit


DISADVANTAGES:-Not suitable for high power conversion

Low amount of dc step up

Non isolated SMPS


APPLICATIONS:-Commonly used as LED driver

Used for Solar power system

Used for Power factor corrections

Used in HVDC system

Applicable for LCD Back & FLASH LIGHTS

Used in HVE(Hybrid electric vehicles)


Fuzzy Logic Controller for Boost Dc-Dc Converter:-

An analysis of boost converter circuit revealed that the inductor

current plays significant task in dynamic response of boost converter.

Additionally, it can provide the storage energy information in the

converter. Thus, any changes on the inductor current may affect

output voltage and output voltage will provide steady state condition

information of converter. However, the three main parameters need to

be considered when designing boost converters are power switch,

inductor and capacitor. In this objective to achieve the desired output

voltage and the stability is by designing the power switch.


CONCLUSION:- Design of a fuzzy logic controller on control boost dc-dc converter by using

MATLAB has been successfully achieved. A simple algorithm based on the prediction of fuzzy logic controller, possibly using the fuzzy rules parameter, is showing to be more convenient than the circuit without fuzzy. As the 20 V input on the output voltage for the closed loop circuit (with fuzzy logic controller) with 0% overshoot shows the better performance compared to the open loop circuit (without fuzzy logic controller) whereby it has 80% overshoot. Moreover, the value of the output current also improving corresponds to the system and produce a constant value for the output current as 0.5 A. This scenario would not happen to the output current of the open loop circuit. Using a closed loop circuit with fuzzy logic controller, it is confirmed that the boost dc-dc converter gives a value of output voltage exactly as circuit requirement. Hence, the closed loop circuit of boost dc-dc converter controlled that by fuzzy logic controller confirmed the methodology and requirement of the proposed approach. These studies could solve many types of problems regardless on stability because as we know that fuzzy logic controller is an intelligent controller to their appliances.


THANK

YOU
