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## Firing angle of UJT as an oscillator Thyristor firing circuit Solution

STEP 0: Pre-Calculation Summary
Formula Used
Firing Angle = Angular frequency in radians/sec*((Resistance*Capacitance)*ln(1/(1-Intrinsic stand-off ratio UJT as Oscillator)))
α = w*((R*C)*ln(1/(1-η)))
This formula uses 1 Functions, 4 Variables
Functions Used
ln - Natural logarithm function (base e), ln(Number)
Variables Used
Angular frequency in radians/sec - Angular frequency in radians/sec is used calculating the angular frequency by using pi as 3.14. (Measured in Radian per Second)
Resistance - Resistance is a measure of the opposition to current flow in an electrical circuit. Its S.I unit is ohm. (Measured in Ohm)
Capacitance - Capacitance is the ratio of the amount of electric charge stored on a conductor to a difference in electric potential. (Measured in Farad)
Intrinsic stand-off ratio UJT as Oscillator- Intrinsic stand-off ratio UJT as Oscillator is defined as the ratio of emitter base 1 resistance to the total emitter base junctions resistances.
STEP 1: Convert Input(s) to Base Unit
Resistance: 10 Ohm --> 10 Ohm No Conversion Required
Intrinsic stand-off ratio UJT as Oscillator: 0.5 --> No Conversion Required
STEP 2: Evaluate Formula
Substituting Input Values in Formula
α = w*((R*C)*ln(1/(1-η))) --> 10*((10*3)*ln(1/(1-0.5)))
Evaluating ... ...
α = 207.944154167984
STEP 3: Convert Result to Output's Unit
207.944154167984 Radian -->11914.3224082454 Degree (Check conversion here)
11914.3224082454 Degree <-- Firing Angle
(Calculation completed in 00.016 seconds)

## < 10+ Thyristors Calculators

Excess work due to thyristor 1 in chopper circuit
Excess energy in chopper circuit = 0.5*Reverse di/dt limiting inductance*((Load current of chopper circuit+(Reverse recovery time*Commutation capacitor voltage)/Reverse di/dt limiting inductance)-(Load current of chopper circuit^2)) Go
Worst case steady state voltage across first thyristor in series connected thyristors
Worst case steady state voltage of thyristor 1 = ((Resultant series voltage of thyristor string+(Number of thyristors in series thyristor string-1)*Resistance*Off state current spread of thyristor string))/Number of thyristors in series thyristor string Go
Voltage across first thyristor in series-connected thyristors
Voltage across thyristor 1 in thyristor string = (Resultant series voltage of thyristor string+(Number of thyristors in series thyristor string-1)*Resistance*Off state current spread of thyristor string)/Number of thyristors in series thyristor string Go
Resultant series voltage of series connected thyristor string
Resultant series voltage of thyristor string = Number of thyristors in series thyristor string*Voltage across thyristor 1 in thyristor string-(Number of thyristors in series thyristor string-1)*Resistance*Off state current spread of thyristor string Go
Maximum Thyristor gate voltage for resistance firing circuit
Maximum gate voltage = Maximum AC input voltage*(Stabilizing Resistance/(Stabilizing Resistance+Variable Resistance+Resistance)) Go
Derating factor of series connected thyristor string
Derating factor of thyristor string = 1-(Resultant series voltage of thyristor string/(Number of thyristors in series thyristor string*Worst case steady state voltage of thyristor 1)) Go
Power dissipated by heat in SCR
Power dissipated by heat in SCR = (SCR junction temperature-SCR ambient temperature)/Thermal resistance of SCR Go
Thermal resistance of SCR
Thermal resistance of SCR = (SCR junction temperature-SCR ambient temperature)/Power dissipated by heat in SCR Go
Leakage current of the collector-base junction
Collector to base leakage current = Collector current-Common base current gain of transistor*Emitter current Go
Discharging current of dv/dt protection thyristor circuits
Discharging current of thyristor circuit = Input voltage/((Resistance+Resistance)) Go

### Firing angle of UJT as an oscillator Thyristor firing circuit Formula

Firing Angle = Angular frequency in radians/sec*((Resistance*Capacitance)*ln(1/(1-Intrinsic stand-off ratio UJT as Oscillator)))
α = w*((R*C)*ln(1/(1-η)))

## Applications of UJT.

An UJT or Unijunction Transistor find many applications just in the domain of power electronics and some of them are :
Relaxation oscillators.
Switching Thyristors like SCR, TRIAC etc.
Magnetic flux sensors.
Voltage or current limiting circuit.
Bistable oscillators.
Voltage or current regulators.
Phase control circuits.

## How to Calculate Firing angle of UJT as an oscillator Thyristor firing circuit?

Firing angle of UJT as an oscillator Thyristor firing circuit calculator uses Firing Angle = Angular frequency in radians/sec*((Resistance*Capacitance)*ln(1/(1-Intrinsic stand-off ratio UJT as Oscillator))) to calculate the Firing Angle, The Firing angle of UJT as an oscillator Thyristor firing circuit formula is defined as as the angle at which the injection of voltage at gate terminal of thyristor causes it to starts conducting. Firing Angle is denoted by α symbol.

How to calculate Firing angle of UJT as an oscillator Thyristor firing circuit using this online calculator? To use this online calculator for Firing angle of UJT as an oscillator Thyristor firing circuit, enter Angular frequency in radians/sec (w), Resistance (R), Capacitance (C) & Intrinsic stand-off ratio UJT as Oscillator (η) and hit the calculate button. Here is how the Firing angle of UJT as an oscillator Thyristor firing circuit calculation can be explained with given input values -> 11914.32 = 10*((10*3)*ln(1/(1-0.5))).

### FAQ

What is Firing angle of UJT as an oscillator Thyristor firing circuit?
The Firing angle of UJT as an oscillator Thyristor firing circuit formula is defined as as the angle at which the injection of voltage at gate terminal of thyristor causes it to starts conducting and is represented as α = w*((R*C)*ln(1/(1-η))) or Firing Angle = Angular frequency in radians/sec*((Resistance*Capacitance)*ln(1/(1-Intrinsic stand-off ratio UJT as Oscillator))). Angular frequency in radians/sec is used calculating the angular frequency by using pi as 3.14, Resistance is a measure of the opposition to current flow in an electrical circuit. Its S.I unit is ohm, Capacitance is the ratio of the amount of electric charge stored on a conductor to a difference in electric potential & Intrinsic stand-off ratio UJT as Oscillator is defined as the ratio of emitter base 1 resistance to the total emitter base junctions resistances.
How to calculate Firing angle of UJT as an oscillator Thyristor firing circuit?
The Firing angle of UJT as an oscillator Thyristor firing circuit formula is defined as as the angle at which the injection of voltage at gate terminal of thyristor causes it to starts conducting is calculated using Firing Angle = Angular frequency in radians/sec*((Resistance*Capacitance)*ln(1/(1-Intrinsic stand-off ratio UJT as Oscillator))). To calculate Firing angle of UJT as an oscillator Thyristor firing circuit, you need Angular frequency in radians/sec (w), Resistance (R), Capacitance (C) & Intrinsic stand-off ratio UJT as Oscillator (η). With our tool, you need to enter the respective value for Angular frequency in radians/sec, Resistance, Capacitance & Intrinsic stand-off ratio UJT as Oscillator and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well.
How many ways are there to calculate Firing Angle?
In this formula, Firing Angle uses Angular frequency in radians/sec, Resistance, Capacitance & Intrinsic stand-off ratio UJT as Oscillator. We can use 1 other way(s) to calculate the same, which is/are as follows -
• Firing Angle = asin(Gate threshold voltage*((Resistance+Stabilizing Resistance+Variable Resistance)/(Maximum AC input voltage*Stabilizing Resistance))) Let Others Know