ET 212 Lab 3 help Multisim NiMydaq

Introduction

The purpose of this lab exercise is to build a half wave rectifier and a full wave rectifier in MULTISIM and on a breadboard. The various output voltage are to be measured. The myDAQ is to be used for data acquisition from the breadboard to the MULTISIM software. The calculate values are to be compared with the measured values to check for consistency.

Equipment/components used

Materials:

1. Simulated Parts (Multisim):

1. 10:1 center-tapped transformer

1. Two diodes 1N4001

1. Two 2.2 kΩ resistors

1. One 100 μF, 50 V electrolytic capacitor

1. One fuse (any rating is fine since it is for simulation only)

1. Hardware Parts (In the Toolbox):

1. Two diodes 1N4001

1. Two 2.2 kΩ resistors

1. One 100 μF, 50 V electrolytic capacitor

1. Virtual Instruments (Multisim):

1. Function Generator (Multisim)

1. Function Generator (NI Elvisms Instrument Launcher)

1. Arbitrary Waveform Generator (NI Elvismx Instrument Launcher)

1. Tektronix oscilloscope (Multisim)

1. Oscilloscope (NI Elvismx Instrument Launcher)

1. Hardware Equipment:

1. Breadboard

1. NI myDAQ Instrument Device

1. Screw Driver

1. Screw Terminal connector

1. Jumper wires

Problem statement

The circuits shown in the figure below both for the half-wave rectifier and a full wave rectifier are to be constructed in MULTISIM and on a breadboard.

Theoretical solution

For the half wave rectifier the calculations are done as follows:

Without filter capacitor

The input voltage is 30V rms. The transformer has a turn-ratio of 10:1

The secondary RMS voltage is: 30V/10=3VRMS

The peak secondary voltage is equal to 3*sqrt(2)= 4.2426V

The peak load voltage is equal to 4.2426-0.7V=3.5426

The RMS load voltage is equal to

The average DC voltage is equal to

The peak to peak ripple voltage is equal to: 3.5426-0=3.5426V

The ripple frequency is equal to the source frequency=60Hz

Half wave rectifier with the filter capacitor:

The filter capacitor is equal to 100uF:

The ripple voltage is equal to

FULL wave rectifier calculations:

The source voltage is equal to 30V rms. The turns-ratio of the transformer is 10:1

The secondary voltage is equal to 30V/(10*2)=1.5V

The peak secondary voltage is equal to 1.5*sqrt(2)= 2.1213V

The peak load voltage is equal to 2.1213-0.7=1.4213V

The RMS load voltage is equal to 1.4213/sqrt(2)=1.005V

The average DC load voltage is equal to: 0.637*1.4213= 0.9054V

The peak to peak ripple voltage is equal to 1.4213V-0V=1.4213V

With the filter capacitor

The ripple frequency is equal to 2*F=1*60Hz=120Hz

The peak to peak ripple voltage is equal to

Experimental procedure

Circuit design

The half wave rectifier is constructed as shown in the figure below:

The full-wave rectifier circuit is constructed as shown below:

Execution/results

Half wave rectifier MULTISIM measurements

1. RMS secondary voltage

1. RMS load voltage

1. Peak to peak ripple voltage

1. Ripple frequency

1. Peak to peak ripple voltage with the filter capacitor

1. Ripple frequency

Half wave rectifier myDAQ measurements

1. Load voltage measurement

1. Secondary voltage measurement

1. Load voltage measurement with the filter capacitor

Full wave rectifier MULTISIM measurements

1. RMS load voltage

1. Peak to peak ripple voltage

1. Ripple frequency

1. Peak to peak voltage with filter capacitor

1. Ripple frequency

Full wave rectifier myDAQ measurements

1. Load voltage without the filter capacitor

1. Load voltage with the filter capacitor

Analysis

The measured and the calculated values were summarized in the tables below:

1. Half –wave rectifier

1. Full wave rectifier values

Review questions

Part 1

1. What is the purpose of having a half-wave rectifier in the circuit?

It converts the positive going cycles of an alternating AC voltage into a pulsating DC voltage.

1. Describe the procedure in this lab to arrive at the final design of both the hardware portion and the software portion to achieve the design objectives?

The connections on the breadboard and in the MULTISIM software were done as per the connection diagram.

1. Discuss the impact of having the capacitor on the output voltage and the effect of additional load on the ripple voltage.

The function of the capacitor is to reduce the ripples in the output voltage and make it more like a DC voltage.

Part 2

1. What is the purpose of having a full-wave rectifier in the circuit?

A full-wave rectifier converts the alternating AC voltage into a pulsating DC voltage. It conducts for both the positive going cycle and the negative going cycle.

1. Describe the procedure in this lab to arrive at the final design of both the hardware portion and the software portion to achieve the design objectives?

The connections on the breadboard and in the MULTISIM software were done as per the connection diagram.

1. Discuss the impact of having the capacitor on the output voltage and the effect of additional load on the ripple voltage.

The function of the capacitor is to reduce the ripples in the output voltage and make it more like a DC voltage.

1. How is the output of the full-wave rectifier different from half-wave rectifier?

The output voltage of a full wave rectifier is more linear than the output voltage of a half wave rectifier.

Conclusion

This lab exercise was a good insight in the study and design of a half wave rectifier and a full wave rectifier. The measured values and the calculated values were very close to each other and thus the lab exercise was a success.