Thyristor
•Download as PPTX, PDF•
1 like•452 views
A thyristor is a four-layer semiconductor device made of alternating P-type and N-type materials. It has three electrodes: an anode, a cathode, and a gate. Thyristors are used in motor speed controls, light dimmers, and other applications to control power output through periodic on-off switching with minimal internal power loss. Common applications include inverters, converters, and other electrical power circuits over 1kV or 100A to control alternating power levels. Thyristors turn from blocking to conducting states at predetermined phases of input voltage waveforms.
Report
Share
Report
Share
Recommended
Thyristors
Thyristors are power semiconductor devices with lower conduction losses and higher power handling capability than transistors but worse switching performance. They conduct current in only one direction when the gate is triggered, turning them on. Common thyristor types include SCRs, TRIACs, and DIACs. Thyristors are often used to control AC currents where they can automatically switch off at zero crossings of the alternating current.
shortkey diode
Schottky diodes operate at high frequencies because they do not have a depletion layer or stored charges. This allows them to turn on and off very quickly without a reverse recovery time. They consist of a metal and n-type semiconductor junction with a low Schottky barrier of 0.15-0.45 volts. At this junction, electrons can easily tunnel from the n-type material to the metal under forward bias. This fast operation makes Schottky diodes useful for rectification at frequencies over 300 MHz and for applications requiring low voltage and fast switching like computers.
Thyrister/SCR
This document provides an overview of power thyristors, also known as SCRs (silicon controlled rectifiers). It discusses the basic construction and operation of thyristors, including:
- Thyristors are four layer semiconductor devices with three terminals - anode, cathode, and gate. The gate controls current flow.
- In forward blocking mode, the device blocks current flow. In forward conduction mode, applying a gate pulse triggers large current flow with a small voltage drop.
- Turning on involves a delay, rise, and spread time as conduction spreads. Turning off passively occurs when current reverses; carrier charges must then be removed.
- Applications include controlling output power
Scr
An SCR (Silicon Controlled Rectifier) is a solid state semiconductor device that controls current flow through its four layers. It functions like a conventional rectifier but is controlled by a gate signal. When the gate receives a threshold voltage, the SCR turns on and conducts current in a forward conducting mode. SCRs are commonly used to produce DC voltages for motors by rectifying AC line voltage through half-wave or full-wave rectification.
Relay basics
This document discusses relays, including their construction, symbol, types, and advantages. A relay is an electromagnetic switch that uses a small electric current to turn on or off a larger current. It has a coil that becomes a magnet when powered, and uses this magnetism to switch contacts like normally open (NO) and normally closed (NC). Relays have multiple poles and throws to control connections. They allow low-power control of high-power loads, and are used in applications like motor control. Relays provide advantages like low control power requirements and switching of larger loads.
Diode
The document discusses diodes, including their history and components. It describes how a diode is constructed from a P-type and N-type semiconductor material, forming a PN junction. At the junction, electrons diffuse into holes, creating a depletion region that acts as an insulator under reverse bias but allows current to flow under forward bias. The document outlines diode applications such as rectification in power supplies and their characteristic I-V curve.
Diodes basics
The basics of electronics can be watched through the link http://bit.ly/2PPv0mv
A Diode is a semiconductor device with two terminals, typically allowing the flow of current in one direction only.
a thermionic valve having two electrodes (an anode and a cathode).
Automatic street light using ldr and relay
The circuit uses an LDR, operational amplifier IC CA3140, and other components to automatically control street lights. The LDR's resistance varies with light intensity, affecting the voltage inputs to the IC. During the day when the LDR resistance is low, the IC output is low and the transistor cuts off, turning off lights. At night when the LDR resistance increases, the IC output goes high, turning on the transistor and lights. A relay is used to control higher power street lights since it can isolate the small IC signal from the larger street light loads.
Recommended
Thyristors
Thyristors are power semiconductor devices with lower conduction losses and higher power handling capability than transistors but worse switching performance. They conduct current in only one direction when the gate is triggered, turning them on. Common thyristor types include SCRs, TRIACs, and DIACs. Thyristors are often used to control AC currents where they can automatically switch off at zero crossings of the alternating current.
shortkey diode
Schottky diodes operate at high frequencies because they do not have a depletion layer or stored charges. This allows them to turn on and off very quickly without a reverse recovery time. They consist of a metal and n-type semiconductor junction with a low Schottky barrier of 0.15-0.45 volts. At this junction, electrons can easily tunnel from the n-type material to the metal under forward bias. This fast operation makes Schottky diodes useful for rectification at frequencies over 300 MHz and for applications requiring low voltage and fast switching like computers.
Thyrister/SCR
This document provides an overview of power thyristors, also known as SCRs (silicon controlled rectifiers). It discusses the basic construction and operation of thyristors, including:
- Thyristors are four layer semiconductor devices with three terminals - anode, cathode, and gate. The gate controls current flow.
- In forward blocking mode, the device blocks current flow. In forward conduction mode, applying a gate pulse triggers large current flow with a small voltage drop.
- Turning on involves a delay, rise, and spread time as conduction spreads. Turning off passively occurs when current reverses; carrier charges must then be removed.
- Applications include controlling output power
Scr
An SCR (Silicon Controlled Rectifier) is a solid state semiconductor device that controls current flow through its four layers. It functions like a conventional rectifier but is controlled by a gate signal. When the gate receives a threshold voltage, the SCR turns on and conducts current in a forward conducting mode. SCRs are commonly used to produce DC voltages for motors by rectifying AC line voltage through half-wave or full-wave rectification.
Relay basics
This document discusses relays, including their construction, symbol, types, and advantages. A relay is an electromagnetic switch that uses a small electric current to turn on or off a larger current. It has a coil that becomes a magnet when powered, and uses this magnetism to switch contacts like normally open (NO) and normally closed (NC). Relays have multiple poles and throws to control connections. They allow low-power control of high-power loads, and are used in applications like motor control. Relays provide advantages like low control power requirements and switching of larger loads.
Diode
The document discusses diodes, including their history and components. It describes how a diode is constructed from a P-type and N-type semiconductor material, forming a PN junction. At the junction, electrons diffuse into holes, creating a depletion region that acts as an insulator under reverse bias but allows current to flow under forward bias. The document outlines diode applications such as rectification in power supplies and their characteristic I-V curve.
Diodes basics
The basics of electronics can be watched through the link http://bit.ly/2PPv0mv
A Diode is a semiconductor device with two terminals, typically allowing the flow of current in one direction only.
a thermionic valve having two electrodes (an anode and a cathode).
Automatic street light using ldr and relay
The circuit uses an LDR, operational amplifier IC CA3140, and other components to automatically control street lights. The LDR's resistance varies with light intensity, affecting the voltage inputs to the IC. During the day when the LDR resistance is low, the IC output is low and the transistor cuts off, turning off lights. At night when the LDR resistance increases, the IC output goes high, turning on the transistor and lights. A relay is used to control higher power street lights since it can isolate the small IC signal from the larger street light loads.
Voltage Regulators ppt
Content
Introduction
Voltage Regulation
Line Regulation
Load Regulation
Series Regulator
Shunt Regulator
Switching Regulator
IC Voltage Regulator
Relay
A relay is an electrically operated switch that uses a small current to control a larger current. Relays were invented in 1835 and use electromagnetic attraction to change switch contacts. A relay has a coil that creates a magnetic field when powered, attracting a lever to change the switch position. Relays can switch AC or DC and higher voltages or currents than simple switches.
Diode
Diodes are semiconductor components that allow current to flow in only one direction. They have two terminals called the anode and cathode. Current can flow from the anode to the cathode but not in the reverse direction. When a forward bias is applied, the depletion region collapses and current can flow through the diode. When a reverse bias is applied, the depletion region expands and blocks current flow. Diodes are used in applications such as rectifiers, reverse current protection, logic gates, and voltage spike suppression.
Zener diode and its applications
This document discusses the Zener diode and its applications. A Zener diode allows current to flow in the reverse direction when a breakdown voltage is reached. Zener diodes can be used as waveform clippers by placing two in series to clip both halves of a signal. They can also act as voltage shifters or regulators. As a voltage regulator, a Zener diode introduced in a circuit with a current source and series resistor can produce a constant output voltage across the load.
Electronic Components
The document defines and describes the basic functions of common electronic components, including resistors, diodes, transistors, capacitors, speakers, motors, and sensors. It explains that resistors limit electrical current, diodes only conduct current in one direction, transistors are used as electronic switches, capacitors store energy, speakers convert electrical signals to sound, and sensors like LDRs convert light levels to resistance.
ZENER DIODE
A Zener diode is a type of diode that permits current not only in the forward direction like a normal diode, but also in the reverse direction if the voltage is larger than the breakdown voltage known as “Zener knee voltage” or “Zener voltage”.
The device is named after American physicist Clarence Melvin Zener, who first described the ZENER EFFECT in1934. Later his work led to the BELL LABS implantation of the effect in form of an electronic device, the ZENER DIODE.
Zener diodes are a modified form of PN silicon diode used extensively for voltage regulation. The P type and N type silicon used is doped more heavily than a standard PN diode.
This causes a very thin depletion region. The zener diodes breakdown characteristics are determined by the doping process
Zeners are commercially available with voltage breakdowns of 1.8 V to 200 V.
When a Zener diode is forward biased, it operates as a normal diode.
In forward biased P side connected to positive and N side connected to negative terminal of battery. In this case the electrons and holes are swept across the junction and large current flow through it.
In case of reverse biased current practically zero and at certain voltage which called Zener voltage the current increases sharply.
Each Zener diode has breakdown rating which specifies the max voltage that can be dropped across it.
Zener diodes are designed to operate in reverse breakdown. Two types of reverse breakdown in a zener diode are AVALANCHE and ZENER. The avalanche break down occurs in both rectifier and zener diodes at a sufficiently high reverse voltage. Zener breakdown occurs in a zener diode at low reverse voltages.
A Zener allows current to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "Zener knee voltage", "Zener voltage", “Avalanche point", or “Peak inverse voltage”
Breakdown Characteristics : Figure 2 shows the reverse portion of a zener diode’s characteristic curve. As the reverse voltage (푉_푅 ) is increased, the reverse current (퐼_푅 ) remains extremely small up to the “knee” of the curve. The reverse current is also called the zener current, 퐼_푍 . At this point, the breakdown effect begins; the internal zener resistance, also called zener impedance (푍_푍), begins to decrease as reverse current increases rapidly.Voltage Regulator :In a DC circuit, Zener diode can be used as a voltage regulator to regulate the voltage across small circuits.
Waveform Clipper :Zener diode can be used to make a Waveform Clipper. Two Zener diodes facing each other in series will act to clip both halves of an input signal.
Voltage Shifter :A Zener diode can be applied to a circuit with a resistor to act as a voltage shifter. This circuit lowers the output voltage by a quantity that is equal to the Zener diode's breakdown voltage.
Light Dependent Resistor
The document discusses the light dependent resistor (LDR), also known as a photoresistor. It describes how an LDR's resistance decreases with increasing light intensity due to the photoconductive effect. LDRs are made of semiconductor materials and can detect light levels and wavelengths. Their resistance ranges from megohms in the dark to kilohms in light. Common uses of LDRs include light sensors, audio compressors, and automatic street/emergency lights.
Function generator
Function generators are electronic test equipment that generate common waveforms like sine, square, and triangular waves over a wide frequency range. They are used to test and develop electronic equipment. Simple function generators generate waveforms by charging and discharging a capacitor with a constant current source, while more advanced arbitrary waveform generators can produce any digitally defined shape using direct digital synthesis techniques. Function generators provide important features like continuous tuning over a broad frequency band, modulation capabilities, and the ability to sweep output frequencies.
Ch_6 Regulated Power Supply (1).ppt
The document discusses different types of power supplies including regulated, unregulated, offline UPS, online UPS, and switch mode power supplies (SMPS). It explains that regulated power supplies use voltage regulating devices like zener diodes or transistors to maintain a constant output voltage regardless of input or load variations. Unregulated supplies do not have this regulation and output voltage fluctuates with input/load. It also compares offline and online UPS configurations and their advantages. Finally, it provides a brief overview of how SMPS work and their benefits over linear power supplies.
Three phase transformers
Three-phase transformers are used for power generation and transmission because they are more efficient and cost-effective than single-phase transformers. They have three cores arranged 120 degrees apart that operate on the principle that the fluxes in each core sum to zero at any given time. Various winding configurations like star-star, delta-delta, star-delta, and delta-star can step voltages up or down as needed. For high loads, three-phase transformers can be connected in parallel as long as their polarities match, phase displacements are aligned, and voltage ratios are equal to prevent circulating currents.
Introduction to active and passive components
This presentation is for beginners of electronics. This will give you a brief about all the important basic building blocks of electronics and hence will be helpful in creating a good foundation.
Schottky diode
This document discusses the Schottky diode, a semiconductor diode with a low forward voltage drop and very fast switching speeds. It forms a metal-semiconductor junction, using a metal like molybdenum or platinum in contact with an N-type semiconductor like silicon. This creates a Schottky barrier and results in fast switching without the charge storage and recovery time of a conventional PN junction diode. Key advantages are voltage drops as low as 0.15V, no reverse recovery time, and operation at frequencies from MHz to GHz. Applications include rectification, switching, and protection circuits.
Thyristor
The document discusses thyristors, which are semiconductor devices that can be used as electrically controlled switches. It provides details on:
- The history and development of thyristors from the 1950s onward.
- The basic construction of a thyristor, which consists of four layers of alternating P-type and N-type semiconductor material.
- The three main modes of operation for thyristors - reverse blocking, forward blocking, and forward conducting.
- Applications of thyristors onboard ships, including use in motor starters, variable frequency drives, converter circuits, and inverter circuits.
Relays
Relays are electrically operated switches that use a low-power signal to control a circuit with higher power. They have various operating principles and types. Relays allow for control of circuits with complete isolation and for one signal to control multiple circuits. Common types include latching, induction, reed, mercury-wetted, and solid-state relays. Relays are used where control of high power loads is needed, such as in protection devices, contactors, stabilizers, inverters, and welders. They provide advantages of fast operation, reliability, and allowing control of AC and DC circuits with one device.
Light Dimmers
Dimmers are devices used to vary the brightness of lights by changing the voltage waveform applied. Early dimmers used inefficient variable resistors or rheostats, but modern dimmers use silicon-controlled rectifiers for higher efficiency. Dimmers are used both in domestic and professional lighting installations, with professional dimmers often controlled digitally via protocols like DMX. Key developments included the first solid-state dimmer by Joel Spira and the introduction of thyristor dimmers which enabled remote analog control.
IGBT
The document discusses insulated gate bipolar transistors (IGBTs). It describes IGBTs as having MOSFET-like input characteristics and bipolar junction transistor-like output characteristics. The document summarizes IGBT structure, working principles, characteristics including transfer and switching characteristics, and methods of connecting IGBTs in series and parallel. It also discusses protection of IGBTs from overvoltage, overcurrent, high dv/dt, and overheating.
Switchgear and protection 4
Circuit Breaking:
Properties of arc
Arc extinction theories
Re-striking voltage transient
Current chopping
Resistance switching
Capacitive current interruption
Short line interruption
Circuit breaker ratings.
Testing Of Circuit Breaker: Classification
Testing station and equipment's
Testing procedure
Direct and indirect testing
welding and welding transformer
i have made a presentation on welding and welding transformer, here i included types of weldings and their advantages and types of welding transformer and their working, construction, application, advantages..
Circuit breakers
Circuit breakers are used to protect electrical circuits from damage caused by overloads or short circuits. They operate automatically to detect faults and interrupt current flow. Modern high power AC circuit breakers use either sulfur hexafluoride gas or a vacuum as insulating mediums to rapidly extinguish arcs when contacts open through cooling and rapidly increasing dielectric strength between contacts. Vacuum circuit breakers provide the fastest interruption and are most compact and reliable due to the superior arc quenching properties of a vacuum.
Presentation about transformer and its types
- A transformer is a static device that changes electrical power at one voltage level into electrical power at another voltage level through magnetic induction. It does not change the frequency.
- There are two main types of transformers: step-up transformers, which increase voltage, and step-down transformers, which decrease voltage. This is achieved by varying the number of turns in the primary and secondary coils.
- Transformers work on the principle of mutual induction. A changing magnetic field induced by alternating current in the primary coil induces a voltage in the secondary coil.
Ape thyristor
Thyristor is a four-layered semiconductor device that can conduct current in one direction when a gate signal is applied. It has the property of latching where it stays in the forward conducting state even after the removal of the gate signal. The document discusses the structure of a thyristor including the doped layers, its operating characteristics like turn on, turn off and static characteristics. It describes the transient behaviors during turn on and turn off and limitations during these processes. The document also covers parameters mentioned in thyristor datasheets and different types of thyristors like SCR, DIAC and TRIAC.
Thyristors,Commutayion of Thyristor, Power Electronics
This document discusses thyristor devices, specifically silicon controlled rectifiers (SCRs). It describes the basic structure and operation of SCRs, including how they are turned on through their gate and turned off by reducing their anode current. The document outlines various ratings of SCRs such as current, voltage, and switching ratings. It also discusses how SCRs can be connected in series and parallel configurations and describes different gate triggering and commutation circuits used to control SCR operation. Finally, it briefly introduces some other types of thyristor devices.
More Related Content
What's hot
Voltage Regulators ppt
Content
Introduction
Voltage Regulation
Line Regulation
Load Regulation
Series Regulator
Shunt Regulator
Switching Regulator
IC Voltage Regulator
Relay
A relay is an electrically operated switch that uses a small current to control a larger current. Relays were invented in 1835 and use electromagnetic attraction to change switch contacts. A relay has a coil that creates a magnetic field when powered, attracting a lever to change the switch position. Relays can switch AC or DC and higher voltages or currents than simple switches.
Diode
Diodes are semiconductor components that allow current to flow in only one direction. They have two terminals called the anode and cathode. Current can flow from the anode to the cathode but not in the reverse direction. When a forward bias is applied, the depletion region collapses and current can flow through the diode. When a reverse bias is applied, the depletion region expands and blocks current flow. Diodes are used in applications such as rectifiers, reverse current protection, logic gates, and voltage spike suppression.
Zener diode and its applications
This document discusses the Zener diode and its applications. A Zener diode allows current to flow in the reverse direction when a breakdown voltage is reached. Zener diodes can be used as waveform clippers by placing two in series to clip both halves of a signal. They can also act as voltage shifters or regulators. As a voltage regulator, a Zener diode introduced in a circuit with a current source and series resistor can produce a constant output voltage across the load.
Electronic Components
The document defines and describes the basic functions of common electronic components, including resistors, diodes, transistors, capacitors, speakers, motors, and sensors. It explains that resistors limit electrical current, diodes only conduct current in one direction, transistors are used as electronic switches, capacitors store energy, speakers convert electrical signals to sound, and sensors like LDRs convert light levels to resistance.
ZENER DIODE
A Zener diode is a type of diode that permits current not only in the forward direction like a normal diode, but also in the reverse direction if the voltage is larger than the breakdown voltage known as “Zener knee voltage” or “Zener voltage”.
The device is named after American physicist Clarence Melvin Zener, who first described the ZENER EFFECT in1934. Later his work led to the BELL LABS implantation of the effect in form of an electronic device, the ZENER DIODE.
Zener diodes are a modified form of PN silicon diode used extensively for voltage regulation. The P type and N type silicon used is doped more heavily than a standard PN diode.
This causes a very thin depletion region. The zener diodes breakdown characteristics are determined by the doping process
Zeners are commercially available with voltage breakdowns of 1.8 V to 200 V.
When a Zener diode is forward biased, it operates as a normal diode.
In forward biased P side connected to positive and N side connected to negative terminal of battery. In this case the electrons and holes are swept across the junction and large current flow through it.
In case of reverse biased current practically zero and at certain voltage which called Zener voltage the current increases sharply.
Each Zener diode has breakdown rating which specifies the max voltage that can be dropped across it.
Zener diodes are designed to operate in reverse breakdown. Two types of reverse breakdown in a zener diode are AVALANCHE and ZENER. The avalanche break down occurs in both rectifier and zener diodes at a sufficiently high reverse voltage. Zener breakdown occurs in a zener diode at low reverse voltages.
A Zener allows current to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "Zener knee voltage", "Zener voltage", “Avalanche point", or “Peak inverse voltage”
Breakdown Characteristics : Figure 2 shows the reverse portion of a zener diode’s characteristic curve. As the reverse voltage (푉_푅 ) is increased, the reverse current (퐼_푅 ) remains extremely small up to the “knee” of the curve. The reverse current is also called the zener current, 퐼_푍 . At this point, the breakdown effect begins; the internal zener resistance, also called zener impedance (푍_푍), begins to decrease as reverse current increases rapidly.Voltage Regulator :In a DC circuit, Zener diode can be used as a voltage regulator to regulate the voltage across small circuits.
Waveform Clipper :Zener diode can be used to make a Waveform Clipper. Two Zener diodes facing each other in series will act to clip both halves of an input signal.
Voltage Shifter :A Zener diode can be applied to a circuit with a resistor to act as a voltage shifter. This circuit lowers the output voltage by a quantity that is equal to the Zener diode's breakdown voltage.
Light Dependent Resistor
The document discusses the light dependent resistor (LDR), also known as a photoresistor. It describes how an LDR's resistance decreases with increasing light intensity due to the photoconductive effect. LDRs are made of semiconductor materials and can detect light levels and wavelengths. Their resistance ranges from megohms in the dark to kilohms in light. Common uses of LDRs include light sensors, audio compressors, and automatic street/emergency lights.
Function generator
Function generators are electronic test equipment that generate common waveforms like sine, square, and triangular waves over a wide frequency range. They are used to test and develop electronic equipment. Simple function generators generate waveforms by charging and discharging a capacitor with a constant current source, while more advanced arbitrary waveform generators can produce any digitally defined shape using direct digital synthesis techniques. Function generators provide important features like continuous tuning over a broad frequency band, modulation capabilities, and the ability to sweep output frequencies.
Ch_6 Regulated Power Supply (1).ppt
The document discusses different types of power supplies including regulated, unregulated, offline UPS, online UPS, and switch mode power supplies (SMPS). It explains that regulated power supplies use voltage regulating devices like zener diodes or transistors to maintain a constant output voltage regardless of input or load variations. Unregulated supplies do not have this regulation and output voltage fluctuates with input/load. It also compares offline and online UPS configurations and their advantages. Finally, it provides a brief overview of how SMPS work and their benefits over linear power supplies.
Three phase transformers
Three-phase transformers are used for power generation and transmission because they are more efficient and cost-effective than single-phase transformers. They have three cores arranged 120 degrees apart that operate on the principle that the fluxes in each core sum to zero at any given time. Various winding configurations like star-star, delta-delta, star-delta, and delta-star can step voltages up or down as needed. For high loads, three-phase transformers can be connected in parallel as long as their polarities match, phase displacements are aligned, and voltage ratios are equal to prevent circulating currents.
Introduction to active and passive components
This presentation is for beginners of electronics. This will give you a brief about all the important basic building blocks of electronics and hence will be helpful in creating a good foundation.
Schottky diode
This document discusses the Schottky diode, a semiconductor diode with a low forward voltage drop and very fast switching speeds. It forms a metal-semiconductor junction, using a metal like molybdenum or platinum in contact with an N-type semiconductor like silicon. This creates a Schottky barrier and results in fast switching without the charge storage and recovery time of a conventional PN junction diode. Key advantages are voltage drops as low as 0.15V, no reverse recovery time, and operation at frequencies from MHz to GHz. Applications include rectification, switching, and protection circuits.
Thyristor
The document discusses thyristors, which are semiconductor devices that can be used as electrically controlled switches. It provides details on:
- The history and development of thyristors from the 1950s onward.
- The basic construction of a thyristor, which consists of four layers of alternating P-type and N-type semiconductor material.
- The three main modes of operation for thyristors - reverse blocking, forward blocking, and forward conducting.
- Applications of thyristors onboard ships, including use in motor starters, variable frequency drives, converter circuits, and inverter circuits.
Relays
Relays are electrically operated switches that use a low-power signal to control a circuit with higher power. They have various operating principles and types. Relays allow for control of circuits with complete isolation and for one signal to control multiple circuits. Common types include latching, induction, reed, mercury-wetted, and solid-state relays. Relays are used where control of high power loads is needed, such as in protection devices, contactors, stabilizers, inverters, and welders. They provide advantages of fast operation, reliability, and allowing control of AC and DC circuits with one device.
Light Dimmers
Dimmers are devices used to vary the brightness of lights by changing the voltage waveform applied. Early dimmers used inefficient variable resistors or rheostats, but modern dimmers use silicon-controlled rectifiers for higher efficiency. Dimmers are used both in domestic and professional lighting installations, with professional dimmers often controlled digitally via protocols like DMX. Key developments included the first solid-state dimmer by Joel Spira and the introduction of thyristor dimmers which enabled remote analog control.
IGBT
The document discusses insulated gate bipolar transistors (IGBTs). It describes IGBTs as having MOSFET-like input characteristics and bipolar junction transistor-like output characteristics. The document summarizes IGBT structure, working principles, characteristics including transfer and switching characteristics, and methods of connecting IGBTs in series and parallel. It also discusses protection of IGBTs from overvoltage, overcurrent, high dv/dt, and overheating.
Switchgear and protection 4
Circuit Breaking:
Properties of arc
Arc extinction theories
Re-striking voltage transient
Current chopping
Resistance switching
Capacitive current interruption
Short line interruption
Circuit breaker ratings.
Testing Of Circuit Breaker: Classification
Testing station and equipment's
Testing procedure
Direct and indirect testing
welding and welding transformer
i have made a presentation on welding and welding transformer, here i included types of weldings and their advantages and types of welding transformer and their working, construction, application, advantages..
Circuit breakers
Circuit breakers are used to protect electrical circuits from damage caused by overloads or short circuits. They operate automatically to detect faults and interrupt current flow. Modern high power AC circuit breakers use either sulfur hexafluoride gas or a vacuum as insulating mediums to rapidly extinguish arcs when contacts open through cooling and rapidly increasing dielectric strength between contacts. Vacuum circuit breakers provide the fastest interruption and are most compact and reliable due to the superior arc quenching properties of a vacuum.
Presentation about transformer and its types
- A transformer is a static device that changes electrical power at one voltage level into electrical power at another voltage level through magnetic induction. It does not change the frequency.
- There are two main types of transformers: step-up transformers, which increase voltage, and step-down transformers, which decrease voltage. This is achieved by varying the number of turns in the primary and secondary coils.
- Transformers work on the principle of mutual induction. A changing magnetic field induced by alternating current in the primary coil induces a voltage in the secondary coil.
What's hot (20)
Viewers also liked
Ape thyristor
Thyristor is a four-layered semiconductor device that can conduct current in one direction when a gate signal is applied. It has the property of latching where it stays in the forward conducting state even after the removal of the gate signal. The document discusses the structure of a thyristor including the doped layers, its operating characteristics like turn on, turn off and static characteristics. It describes the transient behaviors during turn on and turn off and limitations during these processes. The document also covers parameters mentioned in thyristor datasheets and different types of thyristors like SCR, DIAC and TRIAC.
Thyristors,Commutayion of Thyristor, Power Electronics
This document discusses thyristor devices, specifically silicon controlled rectifiers (SCRs). It describes the basic structure and operation of SCRs, including how they are turned on through their gate and turned off by reducing their anode current. The document outlines various ratings of SCRs such as current, voltage, and switching ratings. It also discusses how SCRs can be connected in series and parallel configurations and describes different gate triggering and commutation circuits used to control SCR operation. Finally, it briefly introduces some other types of thyristor devices.
Different types of thyristors and their applications
This article discusses a Thyristors, circuit, and its layer diagram, switching circuits, types of thyristors like SCRs, GTO, ETO, RCTs, and TRIAC
Pillars of Islam and Iman
The document discusses the fundamental pillars of Islam and Iman (faith), including Salat (prayer), Saum (fasting), Hajj (pilgrimage), and Zakat (charity). It summarizes a book called "Pillars of Islam and Iman" which teaches about these pillars that are central to the Islamic faith and belief in a clear and compelling way. The document directs the reader to learn more at www.HilalPlaza.com.
Thyristors and its series and parallel combinations
This document discusses the series and parallel operation of thyristors. It explains that in series operation, voltage sharing networks like resistors are required to evenly distribute the voltage across each thyristor. Uneven current sharing can also occur in parallel operation due to differences in thyristor characteristics, which can cause thermal runaway. Common heat sinks and magnetic coupling are introduced to force equal current sharing among parallel thyristors. The document also discusses applications of thyristor circuits in UPS systems.
Gate Pulse Triggering of Single Phase Thyristor Circuit through Opto-Coupling
The document discusses a thyristor-based controlled rectifier circuit for high voltage DC transmission. It uses opto-couplers to isolate the thyristor triggering circuit from the high voltage AC input. Simulation results using Proteus show that varying the firing angle of the thyristors produces rectified outputs with different voltage levels and ripple factors. Thyristors allow controlled rectification with benefits of efficiency and reliability over uncontrolled rectification for applications like HVDC transmission.
Power electronics(i)
This lecture provides an introduction to power electronics and discusses power semiconductor devices. It introduces different types of power diodes including Schottky diodes, fast recovery diodes, and line frequency diodes. The key differences between these diode types are discussed related to their reverse recovery time and applications. The lecture also discusses the switching characteristics of power diodes and important parameters like reverse recovery time and forward recovery time.
L5 thyristor protection
Part of Lecture series on EE321N, Power Electronics-I delivered by me during Fifth Semester of B.Tech. Electrical Engg., 2012
Z H College of Engg. & Technology, Aligarh Muslim University, Aligarh
Please comment and feel free to ask anything related. Thanks!
أسس الهندسة الإلكترونية
مادة أسس الهندسة الالكترونية - سنة ثالثة - فصل أول- 2012
munthear@ gmail.com - الدكتور المهندس محمد منذر القادري
Thyristor Characteristics, Two Transistor Model Of Thyristor & Thyrisror Turn...
Thyristor Characteristics, Two Transistor Model Of Thyristor & Thyrisror Turn...University of Gujrat, Pakistan
this is all about engineering thyristor is a very important in engineering specially in electrical and electronics engineering.High Power TVS Overvoltage Protection Diodes
This document introduces high power TVS overvoltage protection diodes from Littelfuse. It outlines key parameters like peak pulse current and power ratings. It explains how TVS diodes work, clamping voltage to protect circuits during overvoltage events. TVS diodes offer benefits over MOV crowbar devices like unlimited surge life, smaller package size, and lower clamping voltage for minimum cost protection of AC power lines. Additional resources are provided for technical support and ordering.
SCR
Thyristors are semiconductor devices that act as electrically controlled switches. The document discusses the thyristor family including SCRs, TRIACs, DIACs, and GTOs. It focuses on SCRs, providing details on their construction, V-I characteristics, and triggering methods like gate triggering. SCRs are used in applications like AC-DC converters and inverters as high power switches. TRIACs and DIACs are also briefly introduced.
Thyristors (2)
Thyristors are power semiconductor devices that operate as bi-stable switches and are extensively used in power electronics. A thyristor has a p-n-p-n structure with three p-n junctions and three terminals - anode, cathode, and gate. When the anode voltage exceeds the forward breakdown voltage, the thyristor switches to the conducting state. It can be switched off only by reducing the anode current below the holding current. The document discusses thyristor turn-on methods including gate, thermal, light, and high voltage triggering. Resistance and RC triggering circuits are described for controlling the thyristor firing angle.
Scr (07 Ece 109)
It is a college presentation on Semiconductor controlled rectifiers commonly known as SCR or Thyristor.
Thyristor
Thyristors are solid-state semiconductor devices composed of alternating layers of N-type and P-type materials. They act as electrically controlled switches that can be turned on by a current pulse to the gate terminal, causing the thyristor to conduct current as long as it remains forward biased. Thyristors are used in applications involving high currents and voltages, often for controlling alternating current where they automatically switch off when the current polarity changes. Common applications include lighting dimmers, motor speed controls, and high-voltage direct current electricity transmission.
Five Pillars of Islam
The five pillars of Islam are the core beliefs and practices of the Islamic faith. They are the Shahadah (declaration of faith), Salah (prayer five times a day facing Mecca), Zakah (charity in the form of giving to the less fortunate), Sawm (fasting during the month of Ramadan from dawn to dusk), and Hajj (pilgrimage to Mecca that all Muslims should make once in their lifetime if able).
The pillars of iman
The document discusses the six pillars of Iman (faith) in Islam. The six pillars are: 1) belief in Allah, 2) belief in angels, 3) belief in holy books, 4) belief in prophets, 5) belief in the Day of Judgment, and 6) belief in divine destiny. Each pillar is then further explained with additional details and concepts related to that pillar of faith in Islam.
5 Pillars of Islam
Learn about the 5 Pillars of Islam the Simple and Visual way.
Learn more: http://syukran.com/slides
Thyristor Commutation Techniques
The document discusses different techniques for commutating thyristors, including natural commutation which occurs in AC circuits, and forced commutation which is applied to DC circuits using elements like inductance and capacitance. It describes various methods of forced commutation such as self commutation, resonant pulse commutation, complementary commutation, and impulse commutation. Examples and equations are provided for calculating timing and component values for resonant pulse commutation and complementary commutation circuits.
POWER ELECTRONIC DEVICES
The document provides an overview of power electronic devices. It begins by defining power electronic devices as semiconductor devices used to convert or control electric power. It then discusses the key features of power electronic devices, including that they must handle large power levels and typically operate in switching states. The document outlines the basic configuration of a power electronic system and classifications of devices. It provides details on uncontrolled diodes, half-controlled thyristors, and fully-controlled devices. It also discusses characteristics, specifications, applications and history.
Viewers also liked (20)
Thyristors,Commutayion of Thyristor, Power Electronics
Thyristors,Commutayion of Thyristor, Power Electronics
Different types of thyristors and their applications
Different types of thyristors and their applications
Thyristors and its series and parallel combinations
Thyristors and its series and parallel combinations
Gate Pulse Triggering of Single Phase Thyristor Circuit through Opto-Coupling
Gate Pulse Triggering of Single Phase Thyristor Circuit through Opto-Coupling
Thyristor Characteristics, Two Transistor Model Of Thyristor & Thyrisror Turn...
Thyristor Characteristics, Two Transistor Model Of Thyristor & Thyrisror Turn...
Similar to Thyristor
Thyristors
This document discusses the theory and working of thyristors, which are semiconductor devices used in controlled rectification applications. It explains that thyristors like SCRs conduct current in only one direction when a gate signal is applied, and continue conducting even after the gate signal is removed. The document describes the internal structure of a thyristor and its operation, involving a PNP and NPN transistor structure triggered by a gate signal. It also provides examples of uncontrolled and controlled full-wave rectification using thyristors in bridge configurations, and discusses the principle of DC motor speed control using a thyristor-based drive.
Thyristors.pptx
This document provides an overview of thyristors, including:
1) Thyristors are four-layer semiconductor devices that can handle high currents and voltages with low control power. Common types include SCRs, triacs, and GTOs.
2) Compared to transistors, thyristors have lower conduction losses and higher power handling but worse switching performance.
3) Thyristors operate in forward blocking, forward conducting, or reverse blocking modes depending on voltage polarity. They can be turned on through various methods including gate triggering.
Thyristor
Silicon Controlled Rectifier (SCR) is a unidirectional semiconductor device made of silicon.SCR is a three-terminal, four-layer semiconductor device consisting of alternate layers of p-type and n-type material.
Silicon controlled rectifier
The silicon controlled rectifier (SCR) is a four-layered PNPN semiconductor device that can be used as a switching device in power control applications. It consists of three diodes connected back-to-back, with a gate connection that allows it to be switched on by applying a voltage pulse. Once triggered on, it will remain conducting until the current drops below a minimum holding value. SCRs can be used to precisely control loads by rapidly switching current on and off up to thousands of times per second, combining aspects of a rheostat and switch without their disadvantages.
Scr
This document provides an overview of SCR (silicon controlled rectifier) characteristics and operating principles. It discusses:
1. SCR structure and characteristics, including static and transient two-transistor models.
2. Methods for turning SCRs on, including gate triggering, dv/dt triggering, and light triggering. Turn-on characteristics like delay time and rise time are examined.
3. Methods for turning SCRs off, including natural/line commutation in AC circuits and forced commutation techniques for DC circuits like load side commutation methods.
The document aims to explain SCR functionality and behavior for applications in power electronics circuits. Key aspects like turn-on, turn-
Module 2 thyristors
This document discusses thyristors, which are power semiconductor devices that operate as bistable switches. It covers thyristor characteristics such as static and switching behavior, and triggering methods including gate triggering. Key points include that thyristors can be turned on through thermal, light, voltage, or gate current methods, and turn off when forward current decreases below the holding current. The document also examines thyristor circuits and protection considerations against high di/dt and dv/dt.
Power electronics and applications of semiconductors devices, peripheral effects
Basics of power electronics in mechatronics engineering
thyrister-160302163810.pptx
The document discusses thyristors, which are three-terminal semiconductor devices used for power control. It describes the basic structure of a thyristor as having four alternating layers of n-type and p-type semiconductor materials, forming three p-n junctions. Thyristors have three states - reverse blocking, forward blocking, and forward conducting - and remain conducting once triggered until the current drops below a threshold. The document outlines the discovery and development of thyristors, their construction, operating principles, characteristics, types, advantages, and applications in areas like rectification, relay control, and HVDC transmission.
instrumental transformer.pptx
- Instrument transformers like current transformers (CTs) and potential transformers (PTs) are used to measure high voltages and currents.
- CTs step down the primary current and isolate measuring instruments. PTs step down the primary voltage. This allows the use of lower-rated instruments.
- The key advantages are safety/isolation of the measuring circuit, standardization of instruments, and ability to measure a wide range of values with moderate instruments. Errors in the transformers need to be considered for accurate measurement.
electrical-actuation-systems.ppt
This document provides an overview of different types of actuators and electronic components used in actuator systems. It discusses switching devices like mechanical switches and solid state switches. It also covers solenoids, DC motors, AC motors, stepper motors, and various solid state components like diodes, transistors, thyristors, and MOSFETs that are used to control actuators. Diagrams and explanations of how different actuator components work are provided throughout the document.
Bridge rectifier
This document describes a study of single full wave controlled rectifiers using thyristors with a resistive load. It discusses the experimental setup using various equipment to observe the output voltage waveforms. The key findings are:
1) The output voltage varies with the firing angle α, providing control of the DC voltage between 0° and 180°.
2) A full wave rectifier using two thyristors provides greater output than a half wave rectifier using a single thyristor.
3) Waveforms were observed on an oscilloscope to analyze the relationship between output voltage, current, and firing angle.
Module 2 thyristors
This document discusses thyristors and their characteristics. It begins with an introduction to thyristors, which are bistable semiconductor switches that operate from a nonconducting to conducting state. The document then covers thyristor characteristics such as forward blocking, avalanche breakdown, latching behavior, and turn-on and turn-off mechanisms. Various triggering methods like thermal, optical, voltage, dv/dt, and gate current are explained. Finally, the document discusses thyristor circuits and applications, gate triggering circuits, and protection considerations against high di/dt and dv/dt.
Type of pn junction & rectifiers plus Transistor
The document discusses PN junction diodes, rectifiers, and bridge rectifiers. It begins by explaining the history and workings of PN junction diodes, including the depletion region and forward/reverse biasing. It then covers half-wave and full-wave rectifiers for converting AC to DC. Finally, it describes bridge rectifiers, including their types, working principle, advantages of higher output voltage and efficiency over center-tap rectifiers, and applications in power supplies.
Power Electronic Devices
The document discusses thyristors (also called SCRs). It describes thyristors as 4-layer 3-junction semiconductor devices that can be turned on by applying a gate current. Once on, the gate loses control and it remains on until the anode current drops below the holding current level. The document summarizes the construction, working principles, static and switching characteristics of thyristors including forward and reverse operation, latching/holding currents, turn on/off times. It also discusses different firing circuits used to trigger thyristors like R, RC, and UJT triggering.
PE4MSc_Ch1_SC_devices.pptx
Power diodes are two-terminal pn-junction devices that conduct current in the forward direction when a voltage is applied across their terminals. Modern power diodes have high reliability, breakdown voltage, efficiency, and compactness due to advances in diffusion and epitaxial growth techniques. Power diodes are commonly used in rectification circuits and have characteristics such as forward recovery time, reverse recovery time, and reverse recovery current that determine their switching performance.
POWER DEVICES AND DISPLAY DEVICES
SCR, DIAC, TRIAC, Power BJT, Power MOSFET, IGBT Heat sinks and junction temperature, LED, LCD, Photo transistor, Opto Coupler, Solar cell, CCD.
Power Electronics
Power electronics involves controlling the flow of electrical energy through electronic circuits. Rectifiers and inverters are common examples. Power electronics emphasizes large semiconductor devices, magnetic energy storage, and control methods for nonlinear systems. It plays a central role in energy systems and alternative resources. Power electronic systems efficiently convert electrical energy from one form to another. Power electronics courses cover high voltage switching devices, rectifiers, DC-DC converters, and inverters. Thyristors like SCRs are semiconductor devices that act as open or closed switches for control applications. SCRs are used for power control, backup lighting, and over-voltage protection.
Protection against over voltage under voltage using oamp
This document summarizes an over voltage and under voltage protection circuit. The circuit uses a transformer, diodes, capacitor, resistors, potentiometers, zener diodes, transistors, and a relay to protect electrical appliances from high or low voltage. It works by using the transistors and relay to cut off power when the voltage exceeds safe thresholds. This protects appliances from damage caused by voltage fluctuations. The project was created by seven students and is intended to prevent the damage to electrical equipment that occurs every year due to over and under voltage issues.
Pex ppt.pdf
The document discusses different methods of turning on a thyristor, including temperature triggering, light triggering, forward voltage triggering, and dv/dt triggering. It then describes the most common method - gate triggering using a firing circuit. Various firing circuit designs are discussed, including resistance, RC, UJT, and pulse transformer circuits. The pulse transformer circuit provides electrical isolation between the low voltage gate circuit and the high voltage power circuit. Proper design of the firing circuit is important to reliably turn on the thyristor at the desired time.
Similar to Thyristor (20)
Lecture 2.2_Power electronic devices_Thyristors_2.pdf
Lecture 2.2_Power electronic devices_Thyristors_2.pdf
Power electronics and applications of semiconductors devices, peripheral effects
Power electronics and applications of semiconductors devices, peripheral effects
Protection against over voltage under voltage using oamp
Protection against over voltage under voltage using oamp
Recently uploaded
Community pharmacy- Social and preventive pharmacy UNIT 5
Covered community pharmacy topic of the subject Social and preventive pharmacy for Diploma and Bachelor of pharmacy
RPMS TEMPLATE FOR SCHOOL YEAR 2023-2024 FOR TEACHER 1 TO TEACHER 3
RPMS Template 2023-2024 by: Irene S. Rueco
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UP
This Dissertation explores the particular circumstances of Mirzapur, a region located in the
core of India. Mirzapur, with its varied terrains and abundant biodiversity, offers an optimal
environment for investigating the changes in vegetation cover dynamics. Our study utilizes
advanced technologies such as GIS (Geographic Information Systems) and Remote sensing to
analyze the transformations that have taken place over the course of a decade.
The complex relationship between human activities and the environment has been the focus
of extensive research and worry. As the global community grapples with swift urbanization,
population expansion, and economic progress, the effects on natural ecosystems are becoming
more evident. A crucial element of this impact is the alteration of vegetation cover, which plays a
significant role in maintaining the ecological equilibrium of our planet.Land serves as the foundation for all human activities and provides the necessary materials for
these activities. As the most crucial natural resource, its utilization by humans results in different
'Land uses,' which are determined by both human activities and the physical characteristics of the
land.
The utilization of land is impacted by human needs and environmental factors. In countries
like India, rapid population growth and the emphasis on extensive resource exploitation can lead
to significant land degradation, adversely affecting the region's land cover.
Therefore, human intervention has significantly influenced land use patterns over many
centuries, evolving its structure over time and space. In the present era, these changes have
accelerated due to factors such as agriculture and urbanization. Information regarding land use and
cover is essential for various planning and management tasks related to the Earth's surface,
providing crucial environmental data for scientific, resource management, policy purposes, and
diverse human activities.
Accurate understanding of land use and cover is imperative for the development planning
of any area. Consequently, a wide range of professionals, including earth system scientists, land
and water managers, and urban planners, are interested in obtaining data on land use and cover
changes, conversion trends, and other related patterns. The spatial dimensions of land use and
cover support policymakers and scientists in making well-informed decisions, as alterations in
these patterns indicate shifts in economic and social conditions. Monitoring such changes with the
help of Advanced technologies like Remote Sensing and Geographic Information Systems is
crucial for coordinated efforts across different administrative levels. Advanced technologies like
Remote Sensing and Geographic Information Systems
9
Changes in vegetation cover refer to variations in the distribution, composition, and overall
structure of plant communities across different temporal and spatial scales. These changes can
occur natural.
Chapter 4 - Islamic Financial Institutions in Malaysia.pptx
Chapter 4 - Islamic Financial Institutions in Malaysia.pptxMohd Adib Abd Muin, Senior Lecturer at Universiti Utara Malaysia
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
How to Manage Your Lost Opportunities in Odoo 17 CRM
Odoo 17 CRM allows us to track why we lose sales opportunities with "Lost Reasons." This helps analyze our sales process and identify areas for improvement. Here's how to configure lost reasons in Odoo 17 CRM
How to Add Chatter in the odoo 17 ERP Module
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
Main Java[All of the Base Concepts}.docx
This is part 1 of my Java Learning Journey. This Contains Custom methods, classes, constructors, packages, multithreading , try- catch block, finally block and more.
ANATOMY AND BIOMECHANICS OF HIP JOINT.pdf
it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
How to Setup Warehouse & Location in Odoo 17 Inventory
In this slide, we'll explore how to set up warehouses and locations in Odoo 17 Inventory. This will help us manage our stock effectively, track inventory levels, and streamline warehouse operations.
Pollock and Snow "DEIA in the Scholarly Landscape, Session One: Setting Expec...
Pollock and Snow "DEIA in the Scholarly Landscape, Session One: Setting Expec...National Information Standards Organization (NISO)
This presentation was provided by Steph Pollock of The American Psychological Association’s Journals Program, and Damita Snow, of The American Society of Civil Engineers (ASCE), for the initial session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session One: 'Setting Expectations: a DEIA Primer,' was held June 6, 2024.How to Build a Module in Odoo 17 Using the Scaffold Method
Odoo provides an option for creating a module by using a single line command. By using this command the user can make a whole structure of a module. It is very easy for a beginner to make a module. There is no need to make each file manually. This slide will show how to create a module using the scaffold method.
What is Digital Literacy? A guest blog from Andy McLaughlin, University of Ab...
What is Digital Literacy? A guest blog from Andy McLaughlin, University of Aberdeen
The History of Stoke Newington Street Names
Presented at the Stoke Newington Literary Festival on 9th June 2024
www.StokeNewingtonHistory.com
Advanced Java[Extra Concepts, Not Difficult].docx
This is part 2 of my Java Learning Journey. This contains Hashing, ArrayList, LinkedList, Date and Time Classes, Calendar Class and more.
Walmart Business+ and Spark Good for Nonprofits.pdf
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
Special TechSoup offer for a free 180 days membership, and up to $150 in discounts on eligible orders.
Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
Recently uploaded (20)
Community pharmacy- Social and preventive pharmacy UNIT 5
Community pharmacy- Social and preventive pharmacy UNIT 5
RPMS TEMPLATE FOR SCHOOL YEAR 2023-2024 FOR TEACHER 1 TO TEACHER 3
RPMS TEMPLATE FOR SCHOOL YEAR 2023-2024 FOR TEACHER 1 TO TEACHER 3
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UP
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UP
Chapter 4 - Islamic Financial Institutions in Malaysia.pptx
Chapter 4 - Islamic Financial Institutions in Malaysia.pptx
How to Manage Your Lost Opportunities in Odoo 17 CRM
How to Manage Your Lost Opportunities in Odoo 17 CRM
How to Setup Warehouse & Location in Odoo 17 Inventory
How to Setup Warehouse & Location in Odoo 17 Inventory
Pollock and Snow "DEIA in the Scholarly Landscape, Session One: Setting Expec...
Pollock and Snow "DEIA in the Scholarly Landscape, Session One: Setting Expec...
How to Build a Module in Odoo 17 Using the Scaffold Method
How to Build a Module in Odoo 17 Using the Scaffold Method
What is Digital Literacy? A guest blog from Andy McLaughlin, University of Ab...
What is Digital Literacy? A guest blog from Andy McLaughlin, University of Ab...
Walmart Business+ and Spark Good for Nonprofits.pdf
Walmart Business+ and Spark Good for Nonprofits.pdf
Thyristor
- 2. A thyristor is a four-layer semiconductor device, consisting of alternating P type and N type materials (PNPN). A thyristor usually has three electrodes: an anode, a cathode, and a gate (control electrode). Thyristors are used in motor speed controls, light dimmers, pressure-control systems, and liquid-level regulators
- 3. Thyristor is designed to handle large current and voltage, it is used mainly in electrical power circuit with system voltage more than 1 kV or currents more than 100 A. The main advantage of using thyristors as power control device is that as the power is controlled by periodic on – off switching operation hence (ideally) there is no internal power loss in the device for controlling power in output circuit. Thyristors are commonly used in some alternating power circuits to control alternating output power of the circuit to optimize internal power loss at the expense of switching speed.
- 4. In this case thyristors are turned from forward-blocking into forward-conducting state at some predetermined phase angle of the input sinusoidal anode–cathode voltage waveform. Thyristors are also very popularly used in inverter for converting direct power to alternating power of specified frequency. These are also used in converter to convert an alternating power into alternating power of different amplitude and frequency.This is the most common application of thyristor.
- 5. The operationof the thyristor can be understood from Fig. 2.
- 6. When the thyristor cathode is more positive than the anode then junctions J1 and J3 are reverse biased and the device blocks. When the anode is more positive than the cathode, junctions J1 and J3 are forward biased. As J2 is reverse biased, then the device still blocks forward voltage. If the reverse voltage across J2 is made to reach its avalanche breakdown level then the device conducts like a single forward-biased junction
- 7. The ’two transistor’ model of Fig. 4
- 8. The ’two transistor’ model of Fig. 4 can be used to consider the p-n-p-n structure of a thyristor as the interconnection of an npn transistor T1 and a pnp transistor T2. The collector of T1 provides the base current for T2. Base current for T1 is provided by the external gate current in addition to the collector current from T2. If the gain in the base-collector loop of T1 and T2 exceeds unity then the loop current can be maintained regeneratively. When this condition occurs then both T1 and T2 are driven into saturation and the thyristoris said tobe ’latched’. Theanode tocathode current is then only limited by the external circuit