3401-Lab-Diode-Rectifiers-Regulator-r4 (1)
pdf
keyboard_arrow_up
School
Kennesaw State University *
*We aren’t endorsed by this school
Course
3401
Subject
Electrical Engineering
Date
Feb 20, 2024
Type
Pages
11
Uploaded by hensleywalker
Diode Rectifiers and Regulators EE 3401 Laboratory Exercise Electrical Engineering Department Kennesaw State University 1 Rev. 4 Objectives: Half-wave and full-wave rectifier circuits and a Zener diode regulator circuit as well as the performance improvement of the rectifier circuits caused by adding a filter capacitor are investigated. The Zener diode regulator’s performance with different input voltages is examined. Theoretical and measured results are compared. Introduction: Half- and full-wave rectifiers are commonly used in power supply circuits. Rectifying an ac waveform creates a dc component. Filtering the rectified ac waveform with a capacitor increases the dc level and reduces harmonic content, improving the quality of the rectifier’s output. Let the half-wave rectifier circuit in Fig. 1a have input waveform v
I
= V
m
sin(2
π
ft
) with period T
= 1/
f
. The resulting output waveform is shown in Fig. 1b with the horizontal axis scaled both in time and angle. The average, or dc value of the periodic output waveform is (
)
2
1
1
sin 2
t
avg
dc
m
d
t
V
V
V
ft
V
dt
T
π
=
=
−
∫
(1) Where V
m
is the sine wave amplitude and V
d
is the diode’s forward voltage drop. The peak output voltage is v
o,peak
= V
m
−
V
d
. Integration limits t
1
and t
2
are the times the diode starts and ends conduction. Normalizing the period to angle 2
π
radians simplifies the integration because the period and the limits integration limits θ
1
and θ
2
are independent of frequency and time period T
. Therefore, (a) (b) Fig. 1. Half-wave rectifier (a) circuit and (b) output waveform. v
I
4.7k
Ω
+
−
v
O
+
−
R
L
D
1N4007
0
t
1
θ
1
T
2
π
Time (s)
Angle (rad)
Amplitude (V)
v
Opeak
t
2
θ
2
T/2
π
2 Rev. 4 (
)
2
1
1
sin
2
avg
m
d
V
V
V
d
θ
θ
θ
θ
π
=
−
∫
(2) The diode begins conducting at angle θ
1
and it turns off at and θ
2
: (
)
1
1
2
1
sin
and
d
m
V
V
θ
θ
π
θ
−
=
=
−
(3) The difference ϕ
= θ
2
−
θ
1
is the conduction angle
of the half-wave rectifier. A full-wave bridge rectifier circuit is shown in Fig. 2a with a “floating” signal generator and grounded load resistor, which is the most common configuration of this rectifier. Its output waveform appears in Fig. 2b. Note that the output frequency is twice the input frequency, but the time period T
and angular period 2
π
on the horizontal axis refer to the input waveform. Following a similar development to the half-wave rectifier, the dc output voltage from the full-wave bridge rectifier is (
)
2
1
1
sin
2
avg
m
d
V
V
V
d
θ
θ
θ
θ
π
=
−
∫
(4) (a) (b) Fig. 2. Full-wave bridge rectifier (a) circuit and (b) output waveform. Time and angular periods refer to the input waveform. +
−
v
O
1N4007 (4 Places)
v
I
+
−
Wires not connected!
Red
Black
AWG
R
L
4.7k
Ω
v
Opeak
0
Amplitude (V)
t
1
θ
1
t
2
θ
2
T
2
π
Time (s)
Angle (rad)
T/2
π
3 Rev. 4 where the integration is over half the original waveform’s period and the 2
V
d
term is due to the load current flowing through two diodes. The peak output voltage is v
o,peak
= V
m
−
2
V
d
. The integration limits are found using Eq. 5 with the angles referred to the original input waveform. (
)
1
1
2
1
sin
2
and
d
m
V
V
θ
θ
π
θ
−
=
=
−
(5) However, the full-wave rectifier’s conduction angle must be referred to the output waveform’s period, which is half that of the input so ϕ
= 2(
θ
2
−
θ
1
). If a large filter capacitor is added in parallel with the load resistor for either the half- or full-wave rectifier, the resulting ripple waveform is approximately a sawtooth superimposed on the dc level. Fig. 3 shows a filtered full-wave bridge rectifier circuit and the peak-peak ripple waveform. Each “tooth” in the ripple waveform can be approximated as a right triangle with maximum value equal to v
o,peak
. It can be shown that the approximate peak-peak
ripple amplitude for the filtered half-wave rectifier is ,
,
(half-wave)
o peak
r p
p
v
V
f RC
−
≈
(6) And the approximate peak-peak ripple amplitude for the filtered full-wave rectifier is ,
,
(full-wave)
2
o peak
r p
p
v
V
f RC
−
≈
(7) Where f
is the input waveform’s frequency in Eqs. (6) and (7). In either case, the filtered rectifier’s dc level is approximately ,
,
2
r p
p
avg
o peak
V
V
v
−
≈
−
(8) (a) (b) Fig. 3. Full-wave bridge rectifier with filter capacitor (a) circuit and (b) output ripple waveform. R
L
4.7k
Ω
+
−
v
O
1N4007 (4 Places)
v
I
+
−
Wires not connected!
Red
Black
+
C
47 µF
AWG
v
r, peak-peak
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
4 Rev. 4 A Zener diode is sometimes used as a simple dc voltage reference or voltage regulator using a circuit like the one in Fig. 4. It is an inexpensive alternative to monolithic reference and regulator integrated circuits, but the performance is not as good. The Zener diode’s incremental ac resistance makes this type of regulator’s output voltage vary with load current and applied input voltage. A good voltage regulator acts like a voltage source so its output resistance must be very low, ideally 0. The Zener diode used here has an incremental resistance of a few ohms, which while low, is still too high to consider it as behaving like a voltage source. The Zener diode’s approximate incremental resistance r
z
can be calculated from measurements of the diode’s voltage and current at two different operating points (
v
z1
, i
z1
) and (
v
z2
, i
z2
). 1
2
1
2
z
z
z
z
z
z
z
v
v
v
r
i
i
i
∆
−
≈
=
∆
−
(9) Equipment: Function/Arbitrary Waveform Generator (AWG) Oscilloscope Digital Multimeter (DMM) DC power supply with +12 V output Cables and oscilloscope probes as needed Solderless breadboard Components: Resistors (Qty): 100 Ω
(2), 1.5 k
Ω
(1), 4.7 k
Ω
(1) Capacitor (Qty): 47 µ
F (1) Diodes (Qty): 1N4007 (4), 1N4733A (1) Prelab: Assume the following for calculations in prelab steps 1-3. •
The function generator (AWG) produces a waveform v
I
(
t
) = 10sin (2
π
(60)
t
) when it is loaded as indicated. •
Use the constant voltage drop (CVD) model for the diodes with v
fwd
= V
d
= 0.7 V. Fig. 4. Zener diode voltage regulator. R
L
1.5k
Ω
R
S
200
Ω
1N4733
i
S
i
L
i
Z
v
I
+
−
+
−
v
L
5 Rev. 4 1. Perform the following calculations for the half-wave rectifier in Fig. 1. Put your results in Table 1. a. Determine v
o,peak
, θ
1
, and θ
2
, for the rectifier output waveform of Fig. 1b. b. Calculate the average (dc) value of v
o
(
t
) using Eq. 2. c. Calculate the conduction angle ϕ
. 2. Perform the following calculations for the full-wave rectifier in Fig. 2. Put your results in Table 1. a. Determine v
o,peak
, θ
1
, and θ
2
for the rectifier output waveform of Fig. 2b. b. Calculate the average (dc) value of v
o
(
t
) using Eq. 4. c. Calculate the conduction angle ϕ
. 3. Perform the following calculations for the full-wave rectifier with filter capacitor in Fig. 3. Put your results in Table 1. a. Determine the maximum value of v
o
(
t
), v
o,peak
. b. Determine the peak-to-peak ripple voltage, v
r, peak-peak
. c. Determine the approximate average value of v
O
(
t
). You do not have to use integration. Assume the ripple waveform has an ideal sawtooth shape with each “tooth” being a right triangle having amplitude v
r peak-peak
as in Fig. 3b. d. Sketch a realistic
output waveform including ripple and superimpose it on the unfiltered full-
wave rectifier output waveform. Label the maximum and minimum output voltages, not just the peak-peak value. 4. Perform the following calculations for the Zener-diode voltage regulator in Fig. 4. Use the CVD model for the diode in reverse bias assuming it has a constant voltage drop of 5.1 V. Put your results in Table 2. a. If v
I
= 8 V dc, determine i
S
, i
L
, i
Z
, and v
RL
, the power dissipated in R
S
and the power dissipated in the Zener diode. b. Repeat part (a) for v
I
= 12 V dc. Procedure: General Information 1. a. Some oscilloscope measurement functions refer to command sequences for the Agilent (Keysight) DSO 5014A. b. When using the oscilloscope for dc voltage measurements, use Hi Res or Average acquisition mode and use the smallest V/div scale factor that keeps the trace on the screen. c. The function generator referenced in the instructions is the Agilent (Keysight) 33220A. This generator’s output waveform connector is floating (not connected to power system ground). This enables it to be used as a floating sine wave source for a full-wave bridge rectifier. Half-Wave Rectifier 2. Perform measurements of the half-wave rectifier circuit shown in Fig. 1 as follows.
6 Rev. 4 a. Construct the circuit shown in Fig. 1. b. Set up the function generator. •
Select a 60 Hz, 20 Vp-p sine wave. •
Make sure the function generator is in High-Z mode. •
Enable the function generator output. c. Set up the oscilloscope. •
Monitor the function generator output waveform on the oscilloscope Ch. 1 and the resistor voltage on Ch. 2. •
Use DC coupling on both channels. •
Trigger on Ch. 1 using Auto mode. •
Display at least 2 periods and line up the channel ground references together so the waveforms are superimposed. d. Have the oscilloscope measure the peak (not peak-peak) values of the Ch. 1 and Ch. 2 waveforms and the average value and of the Ch. 2 waveform. •
Verify that the input waveform’s amplitude is 20 Vp-p. •
Have your instructor verify that the display is correct. •
Save a copy of the oscilloscope display. •
Determine the difference between the Ch. 1 and Ch. 2 peak amplitudes. Amplitude difference between input and output: Full-Wave Rectifier 3. Perform measurements of the full-wave rectifier circuit shown in Fig. 5 as follows. a. Construct the circuit shown in Fig. 5. Note:
You cannot connect the function generator to ground in this circuit. It must “float”. If you do the rectifier will not work. Since oscilloscope connectors are connected to power line ground internally, that establishes the circuit 0 V ground reference. For function generators that are connected to ground internally, the full-wave rectifier circuit can be configured for a floating load and the load voltage measured differentially. b. Set up the function generator. •
Select a 60 Hz, 20 Vp-p sine wave. •
Make sure the function generator is in High-Z mode. •
Enable the function generator output.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
7 Rev. 4 c. Set up the oscilloscope. •
You will use a differential measurement technique to monitor the function generator output because you cannot connect oscilloscope ground leads to either function generator lead. You can use test leads or oscilloscope probes for the connections. o
Connect Ch. 1 from the function generator “Red” lead to circuit ground at the resistor. Use DC coupling. o
Connect Ch. 2 from the function generator “Black” lead to the circuit ground at the resistor. Use DC coupling. o
Connect Ch. 3 across the resistor. Use DC coupling. o
Set the Ch. 1, 2, and 3 vertical scale factors to be the same, like 5 V/div. o
Trigger on Ch. 1 using Auto mode. o
Use the Math function and subtract Ch. 2 from Ch. 1 (Ch. 1 −
Ch. 2). A new waveform of a different color will appear. Turn off Ch. 1 and Ch. 2 by pressing the “1” and “2” buttons each twice. The Math waveform will still be displayed. o
In the Math menu you can change the displayed waveform scale factor and offset. •
Display at least 2 periods and line up the channel ground references together so the waveforms are superimposed. d. Have the oscilloscope measure the peak (not peak-peak) values of the Math and Ch. 3 waveforms and the average value and of the Ch. 3 waveform. Use Quick Meas > Select Meas > Max for the peak measurement. •
Have your instructor verify that the display is correct. •
Save a copy of the oscilloscope display. •
Determine the difference between the Math and Ch. 3 peak amplitudes. Amplitude difference between input and output: (a) (b) Fig. 5. Full-wave rectifier circuit (a) schematic showing oscilloscope connections and (b) suggested breadboard layout. +
−
v
O
1N4007 (4 Places)
v
I
+
−
Wires not connected!
Red
Black
AWG
R
L
4.7k
Ω
Red
Black
Red
Black
Ch. 1
Ch. 2
Red
Black
Ch. 3
8 Rev. 4 Filtered Full-Wave Rectifier 4. Perform measurements of the full-wave rectifier circuit with filter capacitor as follows. a. The full-wave rectifier in Fig. 5 is modified by connecting a 47 µ
F capacitor in parallel with the load resistor. •
The capacitor is an electrolytic type and must be connected so the DC voltage has the right polarity. Look at the capacitor case and you will see some “
−
” signs near one of the leads. This lead must be connected to the low voltage side, in this case the circuit ground
. Note: Connecting an electrolytic capacitor backwards could damage it. If the current is high enough it can fail catastrophically.
b. Disable or disconnect the function generator output (don’t turn the function generator off) and connect the capacitor across the load resistor with the correct polarity. c. Enable the function generator output and observe the Ch. 3 waveform. Because the ripple amplitude is small, the output voltage is mostly dc. The average value of the Ch. 3 waveform should be higher than it was in step 2. Note:
When the capacitor charges near the top of the rectified sine wave peaks, it acts like a low impedance. The 50 Ω
internal impedance of the function generator will drop a significant amount of the voltage. The result is distorted peaks in the Math waveform. d. Save a copy of the display with the Ch. 3 and Math waveforms superimposed. e. To measure the ripple waveform more carefully, change Ch. 3 to AC coupling. It will then center the waveform at the Ch. 3 ground reference. Change the Ch. 3 scale factor so the ripple is obvious. Have the oscilloscope measure the Ch. 3 peak-peak amplitude this time. f. Save a copy of the display with just the Ch. 3 waveform displayed. Zener Diode Voltage Regulator 5. Perform measurements of the Zener diode voltage regulator circuit in Fig. 4 as follows. a. Construct the circuit. Use two 100 Ω
resistors connected in series for the 200 Ω
resistor. b. Use the +20 V output of the dc power supply. Set it to +8 V first. c. Use the multimeter as a voltmeter and measure v
L and v
RS
(the voltage across R
S
). Use these values to calculate currents i
S
, i
L
, i
Z
. Enter the appropriate values in Table 2. v
L
: v
RS
: d. Calculate the power dissipated in R
S
and in the Zener diode and put the results in Table 2. e. Set the power supply voltage to +12 V and repeat steps (c) and (d). v
L
: v
RS
: 6. Results documentation summary. a. You should have three oscilloscope screen shots, one each from steps 2, 3, and 4. b. Be sure that you recorded data and calculated results in steps you were asked to.
9 Rev. 4 e. Check with your instructor for additional documentation requirements. Analysis: 1. Consider the half-wave rectifier. Compare theoretical and measured results for the average and the peak output voltages using percent error. Use the theoretical value as reference by subtracting it from the measured value and dividing that result by the theoretical value; then convert to percent. 2. Consider the full-wave rectifier without filter capacitor. Compare theoretical and measured results for the average and the peak output voltages using percent error. 3. Consider the full-wave rectifier with filter capacitor. Compare theoretical and measured results for the average output voltage and the peak-peak ripple voltage using percent error. 4. Determine the approximate diode turn-on voltage from the half-wave rectifier waveforms. 5. How might the function generator’s internal impedance affect the filtered full-wave rectifier’s average output voltage? 6. Consider the Zener diode voltage regulator. Use percent error to compare theoretical and measured values of v
L
, i
Z
, and P
Z
at v
I
= 12 V. 7. Consider the Zener diode voltage regulator. Use data measured at v
I
= 8 V and 12 V to calculate the diode on resistance r
Z
. Does the Zener diode voltage regulator act as a good voltage source (source resistance less than 1 Ω
)? Reference: [1] A. Sedra and K. Smith, Microelectronic Circuits
, 7ed., Oxford University Press, New York, 2015.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
10 Rev. 4 Appendix: Table 1. Calculated and measured rectifier data. Rectifier Prelab Calculations Experimental v
o,peak
(V) Conduction Angle, ϕ
(degrees) V
avg
(V)
V
r,p-p
(V)
v
o,peak
(V)
V
avg
(V)
V
r,p-p
(V)
Half-wave Full-wave Filtered full-wave Table 2. Zener diode voltage regulator data. Prelab Calculations Experimental v
I
(V)
i
S
(mA)
i
Z
(mA)
i
L
(mA)
v
L
(V)
P
RS
(mW)
P
Z
(mW)
i
S
(mA)
i
Z
(mA)
i
L
(mA)
v
L
(V)
P
RS
(mW)
P
Z
(mW)
8 12 Table 3. Errors between measured and calculated rectifier voltages. Rectifier Peak Voltage Error (%) Avg. Voltage Error (%) Peak-Peak Ripple Voltage Error (%) Half-wave Full-wave Filtered full-wave
11 Rev. 4 Table 4. Errors between measured and calculated Zener diode circuit parameters at v
I
= 12 V. Parameter Error (%) Load voltage, v
L
Zener diode current, i
Z
Zener diode power, P
Z
Related Documents
Related Questions
A. Draw the circuit diagram of a simple negative clamper with input and output waveforms (with values) for
an input peak to peak of Vpp = 20 Volts Assume Germanium diode is used.
B. Draw the circuit diagram of a clipper that will produce an output waveform below. From the output
waveform Voltage A is 7.7 and Voltage B is -9.7 .Input peak-to-peak voltage is given as 20 volts. Assume
Silicon diodes are used
A
B
1. For the positive half cycle, the needed battery voltage is
2. For the negative half cycle, the needed battery voltage is
arrow_forward
S-2) a) On the bridge type full wave rectifier circuit given in the figure Plot the current paths for each of the +/- alternans.
b) The waveform of the Vç output voltage is given in the graphs on the side. Draw it in the blank and calculate the peak value and indicate it in the graph. c) Calculate the effective value of the output voltage. (Vç (eff) =… ..?).
Note: Diodes are not ideal. VD = 0.7V.
arrow_forward
b. Calculate the following about the circuit in the figure (If silicon diodes are employed in the rectification);i. the peak value of the output voltage considering the drop across each diode, Vpk.ii. the average voltage, Vdc. iii. The current through the load resistor, IL.iv. The current diode, Id.v. The frequency of the output signal, Fout.vi. Calculate the efficiency of the full wave rectifier expressed in percentage. vii. Sketch a graph of the input and output voltage against time.
arrow_forward
1. A six-pulse uncontrolled recti
load. The inductance is very 1
(a) Determine average load o
(b) Determine the maximum
(c) Determine the maximum
(d) Determine average loac
(e) Carefully sketch the wav
diode conduction pattern.
arrow_forward
The positive peak value of output waveform for
the given circuit diagram is......
(VPP of input is 14 V, Bias voltage is 4 V, Diode is
germanium)
R1
I
D,
VIN
VouT
arrow_forward
A single phase diode bridge rectifier has an input voltage of 240V and supplies a resistive load with a
constant dc current of 10A.
(a)
Sketch a well labeled circuit of the rectifier described above.(b)
Sketch the waveforms for the input voltage, output voltage, input current and output current.
(c)
Determine the maximum input voltage.
(d)
Load resistance.
(e)
Derive an equation for the average output voltage and calculate its value.
(f)
Derive an equation for the RMS value of the output voltage and calculate its value.
(g)
Determine the power dissipated in the load
arrow_forward
Please respond to parts (C), (D), and (F) in the attached image.
arrow_forward
what is the purpose of installing a filter capacitor in a bridge rectifier circuit? Why don't we install a zener diode which reduces the ripple voltage or to get a consistent voltage wave at Vout?
arrow_forward
SEE MORE QUESTIONS
Recommended textbooks for you
Electricity for Refrigeration, Heating, and Air C...
Mechanical Engineering
ISBN:9781337399128
Author:Russell E. Smith
Publisher:Cengage Learning
Related Questions
- A. Draw the circuit diagram of a simple negative clamper with input and output waveforms (with values) for an input peak to peak of Vpp = 20 Volts Assume Germanium diode is used. B. Draw the circuit diagram of a clipper that will produce an output waveform below. From the output waveform Voltage A is 7.7 and Voltage B is -9.7 .Input peak-to-peak voltage is given as 20 volts. Assume Silicon diodes are used A B 1. For the positive half cycle, the needed battery voltage is 2. For the negative half cycle, the needed battery voltage isarrow_forwardS-2) a) On the bridge type full wave rectifier circuit given in the figure Plot the current paths for each of the +/- alternans. b) The waveform of the Vç output voltage is given in the graphs on the side. Draw it in the blank and calculate the peak value and indicate it in the graph. c) Calculate the effective value of the output voltage. (Vç (eff) =… ..?). Note: Diodes are not ideal. VD = 0.7V.arrow_forwardb. Calculate the following about the circuit in the figure (If silicon diodes are employed in the rectification);i. the peak value of the output voltage considering the drop across each diode, Vpk.ii. the average voltage, Vdc. iii. The current through the load resistor, IL.iv. The current diode, Id.v. The frequency of the output signal, Fout.vi. Calculate the efficiency of the full wave rectifier expressed in percentage. vii. Sketch a graph of the input and output voltage against time.arrow_forward
- 1. A six-pulse uncontrolled recti load. The inductance is very 1 (a) Determine average load o (b) Determine the maximum (c) Determine the maximum (d) Determine average loac (e) Carefully sketch the wav diode conduction pattern.arrow_forwardThe positive peak value of output waveform for the given circuit diagram is...... (VPP of input is 14 V, Bias voltage is 4 V, Diode is germanium) R1 I D, VIN VouTarrow_forwardA single phase diode bridge rectifier has an input voltage of 240V and supplies a resistive load with a constant dc current of 10A. (a) Sketch a well labeled circuit of the rectifier described above.(b) Sketch the waveforms for the input voltage, output voltage, input current and output current. (c) Determine the maximum input voltage. (d) Load resistance. (e) Derive an equation for the average output voltage and calculate its value. (f) Derive an equation for the RMS value of the output voltage and calculate its value. (g) Determine the power dissipated in the loadarrow_forward
arrow_back_ios
arrow_forward_ios
Recommended textbooks for you
- Electricity for Refrigeration, Heating, and Air C...Mechanical EngineeringISBN:9781337399128Author:Russell E. SmithPublisher:Cengage Learning
Electricity for Refrigeration, Heating, and Air C...
Mechanical Engineering
ISBN:9781337399128
Author:Russell E. Smith
Publisher:Cengage Learning