Questions tagged [thyristor]
A three-terminal semiconductor device consisting of four layers of alternating type (N or P). The main terminals are the anode and cathode, connected to opposite ends of the four layers. The third terminal is called the gate, and a current trigger at the gate causes the device to conduct if it is forward biased.
217 questions
0 votes
1 answer
102 views
Lowest triac dimming possible without a microprocessor
The usual triac dimmer circuits cannot fully reduce power to zero. The diac trigger voltage can be lowered below the typical 20V (for 120Vrms US mains power), and the RC time constant can be ...
- 916
0 votes
0 answers
110 views
Issue with Current Transformer (CT) -induced Voltage Spikes on the Secondary Terminals Damaging our Thyristor Power Controllers
I’m looking for advice regarding a recurring and potentially dangerous issue we're experiencing with our company’s Thyristor Power Controllers (TPCs). Background: We manufacture both single-phase and ...
0 votes
0 answers
54 views
Static var compensator
I need to implement a control method for SVC reactors, but everything I find when I search only explains the method theoretically without clarifying the control process. For example, how do I ...
- 11
2 votes
1 answer
162 views
Single phase dual converter waveform
I am trying to figure out the Vo2 waveform of the single phase dual converter shown below. At α2, T1' and T2' is triggered and forward biased, thus Vo2 follows the supply voltage. However, when supply ...
- 305
0 votes
0 answers
70 views
How can I control two thyristors in antiparallel?
everyone, I'm trying to control 2 thyristors in antiparallel to let the same portion of each half cycle of the signal pass through a load. I am currently using the following circuit: The thyristor ...
2 votes
1 answer
77 views
AC high current PCB traces
I'm making a circuit that rectifies ( full wave ), with a center tap transformer. Here is my design: As you can see, I want to control the sinusoidal with SCR phase control. My concerns are because ...
-1 votes
1 answer
67 views
An error in triggering the thyristors using optocoupler
In this circuit, before triggering the thyristors and before the yellow pulse (from the microcontroller), the pink signal is zero (end number 4 of the optocoupler). However, the other end of the ...
1 vote
2 answers
96 views
How to use a switch after thyristor gate triggering?
I am considering these two circuits that need to be combined. Initially, I plan to use a pulse from a microcontroller to turn on the gate of thyristors, using them as switches. Once the AC voltage ...
1 vote
0 answers
52 views
Combining mechanical and electronic components for controlled switching in a 230 V single-phase grid system
I would like to ask a question regarding the combined use of a mechanical switch with electronic components. I need a voltage relay that can detect undervoltage or overvoltage in a 230 V single-phase ...
0 votes
2 answers
206 views
Using IGBTs for controlling heating loads
I know traditionally antiparallel connected SCRs (Thyristors) are used in phase-angle control mode to control the heat delivered to an industrial furnace or to control heating loads. Can the same be ...
0 votes
1 answer
85 views
Why does adding an LCD to my Arduino project break the controlling of the SCR?
I found this project which is about controlling the firing angle of SCR using Arduino and it works well. https://simple-circuit.com/arduino-scr-half-wave-controlled-rectifier/ Then I modified the code ...
- 1,980
4 votes
2 answers
219 views
SCR not latching when triggered [closed]
I am attempting to design a circuit to discharge an electrolytic capacitor through a bleeder resistor when someone breaks the line of sight between an IR emitter and phototransistor as a safety ...
- 87
0 votes
0 answers
72 views
Potential ground loop issue in DC-DC common ground circuit
I am trying to setup a dedicated battery for my dash-camera, this will provide continuous power when the ignition is OFF and has a manual NC switch to turn off the circuit when not needed. I ...
- 73
2 votes
4 answers
217 views
How does this overcurrent circuit work?
Could someone explain how this short-circuit protection circuit works? As I understand it, Q4 and Q3 form an equivalent circuit of a thyristor, and it functions as a switch. When the thyristor ...
- 301
0 votes
2 answers
179 views
Conduction of Thyristor and Diode
Consider the following circuit: Let \$ \phi \$ denote the angle for which the thyristor T1 is triggered, i want to know why when \$ \omega t = \theta \in (0, \phi) \$ T2 and D2 are conducting i see ...
- 129