di/dt protection is required to protect thyristor or SCR from the formation of local hot spot due to high value of rate of change of anode current i.e. di/dt near the gate to cathode junction during its turn on process. When a thyristor or SCR...
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October 17, 2018 admin
Power Electronics
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The main difference between latching and holding current of SCR is that latching current is related with turn on process while holding current is related with turn off process of SCR. Latching current of forward biased SCR is the minimum current which anode current must...
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October 15, 2018 admin
Power Electronics
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SCR Turn on methods are the techniques to bring an SCR in forward conduction mode from forward blocking mode. An SCR in forward conduction mode is characterized by low impedance, low voltage drop across anode & cathode and high anode current. The value of anode...
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October 13, 2018 admin
Power Electronics
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Definition of V-I Characteristics of SCR A V-I Characteristic of SCR (Silicon Controlled Rectifier) is the voltage current characteristics. The current through the SCR varies as the Anode to Cathode terminal voltage and Gate to Cathode terminal voltage is varied. The graphical representation of current...
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October 12, 2018 admin
Power Electronics
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Avalanche Breakdown is the process of current carrier multiplication due to collision of thermally generated minority carriers with crystal ions in a lightly doped reverse biased pn junction diode. An avalanche of current carriers is produced in a very short time due to this breakdown of...
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October 10, 2018 admin
Electronics
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A pn junction diode is a two terminal single crystal semiconductor device whose one side is doped with acceptors and other side by donors. Doping with acceptor creates p type semiconductor while doping with donors produces n type. Thus a pn junction is formed in...
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October 9, 2018 admin
Basic Electronics
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Definition Silicon Controlled Rectifier (SCR) is a solid state device used for power control in DC and AC system. An SCR is so called because silicon is used for its construction and its operation as a rectifier can be controlled. Silicon Controlled Rectifier is the...
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October 8, 2018 admin
Power Electronics
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The main difference between Rectification Efficiency and Transformer Utilization Factor (TUF) is that former is measurement of efficiency of rectifier while latter is the measurement of extent to which transformer capacity is utilized. Rectification Efficiency is quantitative measurement of rectifier efficiency. It is ratio of...
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October 7, 2018 admin
Electronics
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What is Freewheling Diode? A freewheeling diode is basically a diode connected across the inductive load terminals to prevent the development of high voltage across the switch. When the inductive circuit is switched off, this diode gives a short circuit path for the flow of...
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October 3, 2018 admin
Electronics
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Transformer Utilization Factor (TUF) is defined as the ratio of DC power output of a rectifier to the effective Transformer VA rating used in the same rectifier. Effective VA Rating of transformer is the average of primary and secondary VA rating of transformer. The formula...
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October 2, 2018 admin
Electronics
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