The document describes the design of a two-stage RC coupled common emitter (CE) amplifier with an overall gain of 1000. It provides the specifications and components required. The design methodology uses a top-down approach, first determining the two-port parameters of each stage and then selecting component values to meet the specifications. Resistors and capacitors are selected to achieve the desired gains of 25 for the first stage and 40 for the second stage, while meeting the bandwidth and input/output impedance requirements.
This document summarizes key concepts and formulas related to electric current, resistance, and Ohm's law from a physics textbook chapter. It includes:
- Formulas for calculating current, charge, resistance, voltage, power, and energy from given values.
- Examples of applying the formulas to calculate values in electric circuits.
- Concepts of resistivity and how resistance changes with temperature based on the material's temperature coefficient of resistance.
This document discusses the electrical properties of p-n junctions. It describes abrupt and linearly graded p-n junction profiles and their depletion widths, electric fields, junction potentials, and capacitances. Equations for the depletion capacitance and diffusion capacitance of abrupt and linearly graded p-n junctions are also presented.
This document discusses diodes and their applications. It begins with an introduction to diodes, including what a diode is, the P-N junction, and diode characteristics when forward and reverse biased. It then covers types of diodes like LEDs, Zener diodes, and more. Applications discussed include logic gates, temperature measurement, and power conversion. The document focuses on rectifiers, explaining half-wave and full-wave rectification and how diodes are used to convert AC to DC in power supplies. Circuit diagrams are provided to illustrate the principles and components of half-wave and full-wave rectifiers, including the addition of a capacitor filter.
The document describes a multistage amplifier configuration where the output of one amplifier stage is connected to the input of the next stage to achieve an overall higher gain. It provides an example of a two-stage cascaded BJT amplifier, showing the individual gains of each stage and how to calculate the overall voltage gain. It also includes diagrams of the amplifier circuit and formulas for input and output impedance.
This presentation was presented to Dr. Chongru Liu in North China Electric Power University,Beijing,China by Mr. Aazim Rasool. This presentation will help to understand the control of HVDC system. Animations are not working like ppt. so I apologize on this.
The document describes the design of a two-stage RC coupled common emitter (CE) amplifier with an overall gain of 1000. It provides the specifications and components required. The design methodology uses a top-down approach, first determining the two-port parameters of each stage and then selecting component values to meet the specifications. Resistors and capacitors are selected to achieve the desired gains of 25 for the first stage and 40 for the second stage, while meeting the bandwidth and input/output impedance requirements.
This document summarizes key concepts and formulas related to electric current, resistance, and Ohm's law from a physics textbook chapter. It includes:
- Formulas for calculating current, charge, resistance, voltage, power, and energy from given values.
- Examples of applying the formulas to calculate values in electric circuits.
- Concepts of resistivity and how resistance changes with temperature based on the material's temperature coefficient of resistance.
This document discusses the electrical properties of p-n junctions. It describes abrupt and linearly graded p-n junction profiles and their depletion widths, electric fields, junction potentials, and capacitances. Equations for the depletion capacitance and diffusion capacitance of abrupt and linearly graded p-n junctions are also presented.
This document discusses diodes and their applications. It begins with an introduction to diodes, including what a diode is, the P-N junction, and diode characteristics when forward and reverse biased. It then covers types of diodes like LEDs, Zener diodes, and more. Applications discussed include logic gates, temperature measurement, and power conversion. The document focuses on rectifiers, explaining half-wave and full-wave rectification and how diodes are used to convert AC to DC in power supplies. Circuit diagrams are provided to illustrate the principles and components of half-wave and full-wave rectifiers, including the addition of a capacitor filter.
The document describes a multistage amplifier configuration where the output of one amplifier stage is connected to the input of the next stage to achieve an overall higher gain. It provides an example of a two-stage cascaded BJT amplifier, showing the individual gains of each stage and how to calculate the overall voltage gain. It also includes diagrams of the amplifier circuit and formulas for input and output impedance.
This presentation was presented to Dr. Chongru Liu in North China Electric Power University,Beijing,China by Mr. Aazim Rasool. This presentation will help to understand the control of HVDC system. Animations are not working like ppt. so I apologize on this.
An Investigation into Even Harmonic Injection in Pole Voltages of a Single Phase Inverter: Presented at National Power Electronics Conference (NPEC) 2010 at Roorkee, India.
The document describes the fixed-bias configuration for an n-channel JFET. It provides equations that relate the input and output quantities for JFETs and shows how to analyze the fixed-bias configuration using both a mathematical and graphical approach. The key points are:
- The fixed-bias configuration has a fixed gate-to-source voltage VGS determined by the fixed DC supply VGG.
- Shockley's equation relates the drain current ID to VGS and can be plotted as a curve.
- For analysis, a vertical line is drawn at the fixed VGS and the point where it intersects the curve determines the operating point (IDQ, VGSQ).
- Both mathematical calculations
HVDC transmission provides several advantages over AC transmission including:
1. No reactive power losses, improved stability, and the ability to control power flow with converters.
2. DC transmission is more economical than AC for distances longer than 500-800km due to reduced infrastructure needs.
3. Technical performance is enhanced with DC such as improved transient stability and fast fault control without circuit breakers.
4. DC links allow asynchronous interconnection between AC systems with different frequencies without disturbances.
This document provides specifications for various classes of soundproof diesel generating sets ranging from 13kVA to 1100kVA. It includes tables listing technical details such as rated voltage, engine specifications, fuel consumption, sound levels and manufacturer for each model. The tables provide classification codes, voltage ratings, outputs, lengths, weights and other key technical specifications.
The document provides 20 multiple choice questions (MCQ) related to electrical engineering topics like circuits, signals and systems, electronics, power systems, and logic gates. Each MCQ is followed by a detailed solution. Some key details:
- MCQ 1-20 cover various EE concepts and each carry 1 mark.
- Topics covered include wattmeters, error analysis, diode characteristics, CRO signals, data storage speeds, transformer circuits, induction motors, SCRs, stability analysis, and logic gates.
- Detailed step-by-step solutions are provided for each MCQ drawing from circuit analyses, definitions, formulas, and concepts.
The document summarizes an engineering student's digital energy meter project. It describes the aims of replacing electromechanical meters with a more accurate digital design. Key aspects included designing hardware with components like a microprocessor, voltage and current processing modules, and developing software using assembly language. The student led a team through conceptualizing, designing, implementing, and demonstrating the working project to examiners over 7 months to complete their degree.
This document describes a water level indicator circuit project created by three students. The circuit uses transistors, resistors, LEDs, and a transformer to indicate water levels. When the brass strip touches water, it provides current to the transistor base, forward biasing the base-emitter and base-collector junctions. This allows collector current to flow and the LED to glow, signaling that the water has reached that level. The circuit leverages the transistor's ability to act as a switch in either cutoff or saturation mode.
Equivalent circuit diagram of a transformer is basically a diagram which can be resolved into an equivalent circuit in which the resistance and leakage reactance of the transformer are imagined to be external to the winding. Where, R1 = Primary Winding Resistance. R2= Secondary winding Resistance.
IC Design of Power Management Circuits (I)Claudia Sin
by Wing-Hung Ki
Integrated Power Electronics Laboratory
ECE Dept., HKUST
Clear Water Bay, Hong Kong
www.ee.ust.hk/~eeki
International Symposium on Integrated Circuits
Singapore, Dec. 14, 2009
The forward converter uses a transformer to step up or down an input dc voltage and provide isolation for the load. It operates in two modes: when the switch is on, the input voltage is applied to the primary winding and power is transferred to the secondary winding and load; when the switch is off, the secondary inductor maintains current through a freewheeling diode. Key aspects of design include transformer turn ratio selection, inductor and capacitor sizing, and duty cycle adjustment for output voltage control. Benefits include better transformer utilization, filtered output, input-output isolation, and higher efficiency compared to flyback converters for power levels of 100-200 watts.
Basic Electrical Engineering Module 1 Part 1Divya15121983
This document provides an overview of basic electrical engineering concepts including Ohm's Law, series and parallel circuits, and Kirchhoff's Laws. It defines Ohm's Law as stating that current is directly proportional to voltage and inversely proportional to resistance. Kirchhoff's Current Law and Voltage Law are introduced as the principles that the algebraic sum of currents at a junction is zero and the algebraic sum of voltages around a closed loop is also zero. An example circuit problem is worked through using these laws to solve for unknown currents.
Temperature Controlled DC fan using ThermistorZaheer Basha
The document describes a temperature controlled DC fan circuit. The circuit uses an NTC thermistor, op amp, transistor, and DC motor to automatically control a fan based on temperature. When the temperature sensed by the thermistor is above a preset level, the op amp activates the transistor, powering the DC motor and turning the fan on. When the temperature returns to normal, the fan turns off. The circuit provides automatic temperature control of devices in a simple and economical way.
Active power is the power actually consumed and measured in kW or MW. Reactive power flows back and forth in a circuit and is measured in kVAR or MVAR. Apparent power is the product of voltage and current and is measured in kVA or MVA. These three powers are related and their relationship can be depicted in a power triangle diagram, with active power on the real axis, reactive power on the imaginary axis, and apparent power as the length of the complex power vector. Power factor is the ratio of active power to apparent power and indicates how effectively power is being used in a circuit.
This document provides information on inverters, including:
- Inverters convert DC input voltage into AC output voltage of desired magnitude and frequency. They are also known as DC-AC converters.
- Inverters can be classified as single-phase or three-phase, and by the type of switching device used (BJT, MOSFET, IGBT, GTO).
- Applications include variable speed AC motors, induction heating, UPS systems. Inputs can be batteries, fuel cells, solar cells.
- Circuit diagrams and operating principles are provided for single-phase half-bridge, full-bridge, and three-phase inverters using 1800 and 1200 conduction modes.
This document discusses synchronous machines and synchronous generators. It contains the following key points:
1. Synchronous machines operate at a constant synchronous speed that is determined by the electrical frequency and number of poles. They can operate as generators or motors.
2. Synchronous generators are widely used in large power applications due to their high efficiency, reliability, and ability to control power factor. They have a rotor winding supplied by DC current and a stator connected to the AC supply.
3. The internal generated voltage of a synchronous generator depends on factors like flux, speed of rotation, and field current. It can supply either lagging or leading reactive current to the system.
4. An open circuit test is
Knowledge sharing on UPS System (Updated).pptxRilwan19
Presentation on UPS system
An uninterruptible power supply (UPS), also known as a power backup, provides backup power when your regular power source fails or voltage drops to an unacceptable level.
A UPS allows for the safe, orderly shutdown of connected equipment. The size and design of a UPS determine how long it will supply power.
An uninterruptible power supply (UPS) is used to protect critical loads from utility-supplied power problems, including spikes, brownouts, fluctuations and power outages, all using a dedicated battery.
This document discusses a class on electrical measurements focusing on potentiometers. It provides an overview of potentiometers including their general principle, types (DC and AC), and applications in calibration. It describes how potentiometers work by comparing an unknown voltage to a known reference voltage to achieve a null reading. The document outlines standardization of potentiometers to accurately measure voltages and details different potentiometer designs including slide wire, vernier, and multiple range types.
This document discusses wireless power transmission. It describes how the concept was realized by Nikola Tesla and can eliminate the need for copper cables. The project aims to wirelessly transfer power over short ranges, such as charging pacemaker batteries implanted in the body. It uses an electronic circuit to convert AC to high frequency AC and transfer power from a primary coil to a secondary coil separated by a few centimeters through resonance. Potential applications include wirelessly charging phones, laptops, and other devices.
Power diodes are key components in rectifier circuits used in AC/DC converters. There are several types of power diodes including general purpose diodes, fast recovery diodes, and Schottky diodes. General purpose diodes have high reverse recovery times around 25μs and are used in low speed applications. Fast recovery diodes have very low reverse recovery times under 5μs and are used in switching circuits. Schottky diodes have the lowest forward voltage drop and recovery times in the nanosecond range but are limited to voltages below 100V. Key ratings for power diodes include peak inverse voltage, maximum average forward current, and reverse recovery time.
Temperature Based Fan Controller can be used for reducing the power consumption & also to assist people who are disabled and are unable to control the speed of fan.It may also be used for monitoring changes in environment.
An Investigation into Even Harmonic Injection in Pole Voltages of a Single Phase Inverter: Presented at National Power Electronics Conference (NPEC) 2010 at Roorkee, India.
The document describes the fixed-bias configuration for an n-channel JFET. It provides equations that relate the input and output quantities for JFETs and shows how to analyze the fixed-bias configuration using both a mathematical and graphical approach. The key points are:
- The fixed-bias configuration has a fixed gate-to-source voltage VGS determined by the fixed DC supply VGG.
- Shockley's equation relates the drain current ID to VGS and can be plotted as a curve.
- For analysis, a vertical line is drawn at the fixed VGS and the point where it intersects the curve determines the operating point (IDQ, VGSQ).
- Both mathematical calculations
HVDC transmission provides several advantages over AC transmission including:
1. No reactive power losses, improved stability, and the ability to control power flow with converters.
2. DC transmission is more economical than AC for distances longer than 500-800km due to reduced infrastructure needs.
3. Technical performance is enhanced with DC such as improved transient stability and fast fault control without circuit breakers.
4. DC links allow asynchronous interconnection between AC systems with different frequencies without disturbances.
This document provides specifications for various classes of soundproof diesel generating sets ranging from 13kVA to 1100kVA. It includes tables listing technical details such as rated voltage, engine specifications, fuel consumption, sound levels and manufacturer for each model. The tables provide classification codes, voltage ratings, outputs, lengths, weights and other key technical specifications.
The document provides 20 multiple choice questions (MCQ) related to electrical engineering topics like circuits, signals and systems, electronics, power systems, and logic gates. Each MCQ is followed by a detailed solution. Some key details:
- MCQ 1-20 cover various EE concepts and each carry 1 mark.
- Topics covered include wattmeters, error analysis, diode characteristics, CRO signals, data storage speeds, transformer circuits, induction motors, SCRs, stability analysis, and logic gates.
- Detailed step-by-step solutions are provided for each MCQ drawing from circuit analyses, definitions, formulas, and concepts.
The document summarizes an engineering student's digital energy meter project. It describes the aims of replacing electromechanical meters with a more accurate digital design. Key aspects included designing hardware with components like a microprocessor, voltage and current processing modules, and developing software using assembly language. The student led a team through conceptualizing, designing, implementing, and demonstrating the working project to examiners over 7 months to complete their degree.
This document describes a water level indicator circuit project created by three students. The circuit uses transistors, resistors, LEDs, and a transformer to indicate water levels. When the brass strip touches water, it provides current to the transistor base, forward biasing the base-emitter and base-collector junctions. This allows collector current to flow and the LED to glow, signaling that the water has reached that level. The circuit leverages the transistor's ability to act as a switch in either cutoff or saturation mode.
Equivalent circuit diagram of a transformer is basically a diagram which can be resolved into an equivalent circuit in which the resistance and leakage reactance of the transformer are imagined to be external to the winding. Where, R1 = Primary Winding Resistance. R2= Secondary winding Resistance.
IC Design of Power Management Circuits (I)Claudia Sin
by Wing-Hung Ki
Integrated Power Electronics Laboratory
ECE Dept., HKUST
Clear Water Bay, Hong Kong
www.ee.ust.hk/~eeki
International Symposium on Integrated Circuits
Singapore, Dec. 14, 2009
The forward converter uses a transformer to step up or down an input dc voltage and provide isolation for the load. It operates in two modes: when the switch is on, the input voltage is applied to the primary winding and power is transferred to the secondary winding and load; when the switch is off, the secondary inductor maintains current through a freewheeling diode. Key aspects of design include transformer turn ratio selection, inductor and capacitor sizing, and duty cycle adjustment for output voltage control. Benefits include better transformer utilization, filtered output, input-output isolation, and higher efficiency compared to flyback converters for power levels of 100-200 watts.
Basic Electrical Engineering Module 1 Part 1Divya15121983
This document provides an overview of basic electrical engineering concepts including Ohm's Law, series and parallel circuits, and Kirchhoff's Laws. It defines Ohm's Law as stating that current is directly proportional to voltage and inversely proportional to resistance. Kirchhoff's Current Law and Voltage Law are introduced as the principles that the algebraic sum of currents at a junction is zero and the algebraic sum of voltages around a closed loop is also zero. An example circuit problem is worked through using these laws to solve for unknown currents.
Temperature Controlled DC fan using ThermistorZaheer Basha
The document describes a temperature controlled DC fan circuit. The circuit uses an NTC thermistor, op amp, transistor, and DC motor to automatically control a fan based on temperature. When the temperature sensed by the thermistor is above a preset level, the op amp activates the transistor, powering the DC motor and turning the fan on. When the temperature returns to normal, the fan turns off. The circuit provides automatic temperature control of devices in a simple and economical way.
Active power is the power actually consumed and measured in kW or MW. Reactive power flows back and forth in a circuit and is measured in kVAR or MVAR. Apparent power is the product of voltage and current and is measured in kVA or MVA. These three powers are related and their relationship can be depicted in a power triangle diagram, with active power on the real axis, reactive power on the imaginary axis, and apparent power as the length of the complex power vector. Power factor is the ratio of active power to apparent power and indicates how effectively power is being used in a circuit.
This document provides information on inverters, including:
- Inverters convert DC input voltage into AC output voltage of desired magnitude and frequency. They are also known as DC-AC converters.
- Inverters can be classified as single-phase or three-phase, and by the type of switching device used (BJT, MOSFET, IGBT, GTO).
- Applications include variable speed AC motors, induction heating, UPS systems. Inputs can be batteries, fuel cells, solar cells.
- Circuit diagrams and operating principles are provided for single-phase half-bridge, full-bridge, and three-phase inverters using 1800 and 1200 conduction modes.
This document discusses synchronous machines and synchronous generators. It contains the following key points:
1. Synchronous machines operate at a constant synchronous speed that is determined by the electrical frequency and number of poles. They can operate as generators or motors.
2. Synchronous generators are widely used in large power applications due to their high efficiency, reliability, and ability to control power factor. They have a rotor winding supplied by DC current and a stator connected to the AC supply.
3. The internal generated voltage of a synchronous generator depends on factors like flux, speed of rotation, and field current. It can supply either lagging or leading reactive current to the system.
4. An open circuit test is
Knowledge sharing on UPS System (Updated).pptxRilwan19
Presentation on UPS system
An uninterruptible power supply (UPS), also known as a power backup, provides backup power when your regular power source fails or voltage drops to an unacceptable level.
A UPS allows for the safe, orderly shutdown of connected equipment. The size and design of a UPS determine how long it will supply power.
An uninterruptible power supply (UPS) is used to protect critical loads from utility-supplied power problems, including spikes, brownouts, fluctuations and power outages, all using a dedicated battery.
This document discusses a class on electrical measurements focusing on potentiometers. It provides an overview of potentiometers including their general principle, types (DC and AC), and applications in calibration. It describes how potentiometers work by comparing an unknown voltage to a known reference voltage to achieve a null reading. The document outlines standardization of potentiometers to accurately measure voltages and details different potentiometer designs including slide wire, vernier, and multiple range types.
This document discusses wireless power transmission. It describes how the concept was realized by Nikola Tesla and can eliminate the need for copper cables. The project aims to wirelessly transfer power over short ranges, such as charging pacemaker batteries implanted in the body. It uses an electronic circuit to convert AC to high frequency AC and transfer power from a primary coil to a secondary coil separated by a few centimeters through resonance. Potential applications include wirelessly charging phones, laptops, and other devices.
Power diodes are key components in rectifier circuits used in AC/DC converters. There are several types of power diodes including general purpose diodes, fast recovery diodes, and Schottky diodes. General purpose diodes have high reverse recovery times around 25μs and are used in low speed applications. Fast recovery diodes have very low reverse recovery times under 5μs and are used in switching circuits. Schottky diodes have the lowest forward voltage drop and recovery times in the nanosecond range but are limited to voltages below 100V. Key ratings for power diodes include peak inverse voltage, maximum average forward current, and reverse recovery time.
Temperature Based Fan Controller can be used for reducing the power consumption & also to assist people who are disabled and are unable to control the speed of fan.It may also be used for monitoring changes in environment.
7. 10 第 2 章 二極體之特性及應用電路實驗
步驟 5:依據圖 2-43 所示,將半波整流電路接妥。
圖 2-43 半波整流電路
步驟 6:如圖 2-44 所示,利用示波器雙軌跡的 CH1 測量次級圈 iV 的波形,
CH2 測量 oV 的波形,將示波器的輸入選擇開關(AC-GND-DC)置於
DC,並記錄 iV 與 oV 的波形於表 2-8 中。
圖 2-44 半波整流電路測量圖
*表 2-8 半波整流電路 iV 與 oV 的波形
iV
VOLTS/DIV 5V
P PV - 17V
TIME/DIV 5ms
T 16.67ms
f 60Hz
8. 第 2 章 二極體之特性及應用電路實驗 11
oV
VOLTS/DIV 5V
P PV - 7.77V
TIME/DIV 5ms
T 16.67ms
f 60Hz
步驟 7:依據表 2-8 所測量的波形,判斷輸出波形 oV 的頻率是否與輸入波形
iV 的頻率相同? 是 (是或否)。
步驟 8:將三用電表置於 ACV 檔,測量次級圈 iV 的有效值電壓,並記錄於
表 2-9 中。再將三用電表置於 DCV 檔,測量負載電阻 LR 兩端的輸
出直流電壓 dcV ,並記錄於表 2-9 中。請根據測量所得到的數值,判
斷是否與理論值接近? 是 (是或否)。
*表 2-9 半波整流電路 i(rms)V 、 mV 與 dcV 的電壓
項目
次級圈有效
值電壓 i(rms)V
次級圈峰值電壓 mV 輸出直流電壓 dcV
理論值 6V mV = i(rms)2 V = 8.49 V dcV =0.318 mV = 2.67 V
測量值 6V 8.49 2.36V
實習項目 4 半波整流濾波電路
步驟 1:依據圖 2-45 所示,將電路接妥,並於電阻器 LR 兩端並聯一個電容
器 C=47μF/25V。
圖 2-45 半波整流濾波電路
9. 12 第 2 章 二極體之特性及應用電路實驗
步驟 2:如圖 2-46 所示,利用示波器雙軌跡的 CH1 測量次級圈 iV 的波形,
CH2 測量 oV 的波形,將示波器的輸入選擇開關(AC-GND-DC)置於
DC,並記錄 iV 與 oV 的波形於表 2-10 中。
圖 2-46 半波整流濾波電路量測圖
*表 2-10 半波整流濾波電路 iV 與 oV 的波形(C=47μF)
iV
VOLTS/DIV 5V
P PV - 17V
TIME/DIV 5ms
T 16.67ms
f 60Hz
oV
VOLTS/DIV 5V
P PV - 2V
TIME/DIV 5ms
T 16.67ms
f 60Hz
10. 第 2 章 二極體之特性及應用電路實驗 13
步驟 3:將三用電表置於 DCV 檔,測量負載電阻 LR 兩端的輸出直流電壓
dcV ,記錄於表 2-11 中。再將示波器的輸入選擇開關(AC-GND-DC)
置於 AC,測量輸出漣波 rV 的波形與振幅,記錄於表 2-11 中,並計
算漣波百分比 r%。
*表 2-11 半波整流濾波電路之漣波百分比(C=47μF)
C C=47μ F
dcV dcV = 6.73 V
rV
VOLTS/DIV 1V
r(P P)V - = 2 V
r(P P)
r(rms)
V
V
2 3
-
=
= 0.58 V
P PV - 2V
TIME/DIV 5ms
T 16.67ms
f 60Hz
r% r%=
r(rms)
dc
V
100%
V
= 8.62%
步驟 4:將電容器 C 改為 470μ F/25V,利用示波器雙軌跡的 CH1 測量次級圈
iV 的波形, CH2 測量 oV 的波形,將示波器的輸入選擇開關
(AC-GND-DC)置於 DC,並記錄 iV 與 oV 的波形於表 2-12 中。
*表 2-12 半波整流濾波電路 iV 與 oV 的波形(C=470μF)
iV
VOLTS/DIV 5V
P PV - 17V
TIME/DIV 5ms
T 16.67ms
f 60Hz
11. 14 第 2 章 二極體之特性及應用電路實驗
oV
VOLTS/DIV 5V
P PV - 0.25V
TIME/DIV 5ms
T 16.67ms
f 60Hz
步驟 5:再將三用電表置於 DCV 檔,測量負載電阻 LR 兩端的輸出直流電壓
dcV ,記錄於表 2-13 中。示波器輸入選擇開關置於 AC,測量輸出漣
波 rV 的波形與振幅,記錄於表 2-13 中,並計算漣波百分比 r%。
*表 2-13 半波整流濾波電路之漣波百分比(C=470μF)
C C=470μF
dcV dcV = 7.6 V
rV
VOLTS/DIV 100mV
r(P P)V - = 0.25 V
r(P P)
r(rms)
V
V
2 3
-
=
= 0.072 V
P PV - 0.25V
TIME/DIV 5ms
T 16.67ms
f 60Hz
r% r%=
r(rms)
dc
V
100%
V
= 0.95%
步驟 6:根據表 2-11 與 2-13 中的數據,我們知道當濾波電容量 C 愈大時,
其漣波百分比愈 小 (大或小)。反之,當濾波電容量 C 愈小時,
其漣波百分比愈 大 (大或小)。
18. 第 2 章 二極體之特性及應用電路實驗 21
(a)逆向偏壓 (b)逆向偏壓
圖 2-52 橋式整流器量測圖
步驟 6:依據圖 2-53 所示,將橋式全波整流電路接妥。
圖 2-53 橋式全波整流電路
步驟 7:如圖 2-54 所示,先利用示波器單軌跡的 CH1 測量次級圈 iV 的波形
後,再測量 oV 的波形,將示波器的輸入選擇開關(AC-GND-DC)置於
DC,並記錄 iV 與 oV 的波形於表 2-20 中。
圖 2-54 橋式全波整流電路測量圖
19. 22 第 2 章 二極體之特性及應用電路實驗
*表 2-20 橋式全波整流電路 iV 與 oV 的波形
iV
VOLTS/DIV 5V
P PV - 17V
TIME/DIV 5ms
T 16.67ms
f 60Hz
oV
VOLTS/DIV 5V
P PV - 7.75V
TIME/DIV 5ms
T 8.33ms
f 120Hz
步驟 8:依據表 2-20 所測量的波形,判斷輸出波形 oV 的頻率是否為輸入波形
iV 的兩倍? 是 (是或否)。
步驟 9:將三用電表置於 ACV 檔,測量次級圈 iV 的有效值電壓,並記錄於
表 2-21 中。再將三用電表置於 DCV 檔,測量負載電阻 LR 兩端的輸
出直流電壓 dcV ,並記錄於表 2-21 中。請根據測量所得到的數值,
判斷是否與理論值接近? 是 (是或否)。
*表 2-21 橋式全波整流電路 i(rms)V 、 mV 與 dcV 的電壓
項目
次級圈有效值電壓
i(rms)V
次級圈峰值電壓 mV 輸出直流電壓 dcV
理論值 6V
mV = i(rms)2 V
= 8.49 V
dcV =0.636 mV
= 5.4 V
測量值 6V 8.49V 4.7V
20. 第 2 章 二極體之特性及應用電路實驗 23
實習項目 8 橋式全波整流濾波電路
步驟 1:依據圖 2-55 所示,將電路接妥,並於電阻器 LR 1k= 兩端並聯一個
電容器 C=47μ F/25V。
圖 2-55 橋式全波整流濾波電路
步驟 2:如圖 2-56 所示,先利用示波器單軌跡的 CH1 測量次級圈 iV 的波形
後,再測量 oV 的波形,將示波器的輸入選擇開關(AC-GND-DC)置於
DC,並記錄 iV 與 oV 的波形於表 2-22 中。
圖 2-56 橋式全波整流濾波電路量測圖
21. 24 第 2 章 二極體之特性及應用電路實驗
*表 2-22 橋式全波整流濾波電路 iV 與 oV 的波形
iV
VOLTS/DIV 5V
P PV - 17V
TIME/DIV 5ms
T 16.67ms
f 60Hz
oV
VOLTS/DIV 5V
P PV - 0.95V
TIME/DIV 5ms
T 8.33ms
f 120Hz
步驟 3:將三用電表置於 DCV 檔,測量負載電阻 LR 兩端的輸出直流電壓
dcV ,記錄於表 2-23 中。再將示波器的輸入選擇開關(AC-GND-DC)
置於 AC,測量輸出漣波 rV 的波形與振幅,記錄於表 2-23 中,並計
算漣波百分比 r%。
*表 2-23 橋式全波整流濾波電路之漣波百分比
LR LR 1k=
dcV dcV = 7.27 V
rV
VOLTS/DIV 500mV
r(P P)V - = 1 V
r(P P)
r(rms)
V
V
2 3
-
=
= 0.289 V
P PV - 1V
TIME/DIV 5ms
T 8.33ms
f 120Hz
r% r%=
r(rms)
dc
V
100%
V
= 3.97%
26. 第 2 章 二極體之特性及應用電路實驗 29
圖 2-64 稽納二極體雙截波電路測量圖
步驟 3:利用示波器雙軌跡的 CH1 測量輸入信號 iV,CH2 測量輸出信號 oV ,
並調整函數波信號產生器,使輸入信號 iV 為不含直流準位的 1kHz、
P P20V - 正弦波,並且將輸入信號 iV 與輸出信號 oV 的波形、振幅、週
期、頻率記錄於表 2-27 中。
*表 2-27 稽納二極體雙截波電路的 iV 與 oV 波形
iV
VOLTS/DIV 5V
P PV - 20V
TIME/DIV 200
T 1ms
f 1kHz
27. 30 第 2 章 二極體之特性及應用電路實驗
oV
VOLTS/DIV 5V
P PV - 11V
TIME/DIV 200
T 1ms
f 1kHz
第 3 部分 探究問題
1. 請找一台個人電腦所使用的電源供應器,拆開後找一找有沒有電源變壓
器,若沒有,請說明為什麼個人電腦所使用的電源供應器沒有電源變壓器?
說明:
(1)個人電腦所使用的電源供應器沒有電源變壓器。
(2)個人電腦所使用的電源供應器是交換式電源供應器,不需要電源變壓
器,所以交換式電源供應器的體積小、重量輕而且效率高,雖然在電路
結構上比較複雜,同時,輸出漣波比較大、電磁干擾也比較大,但整體
而言,交換式電源供應器仍優於傳統線性式電源供應器,所以目前電源
供應器的市場仍然以切換式電源供應器為主流。
第 4 部分 實習心得