- #1
buildingblocs
- 17
- 1
Conduction Angle in SCR Single Phase Rectifiers
- Thread starter buildingblocs
- Start date
-
- Tags
- Angle Conduction Phase Scr
Click For Summary
Discussion Overview
The discussion revolves around the concept of the conduction angle (θ) in single-phase SCR (Silicon Controlled Rectifier) half-wave rectifiers with an RL load. Participants explore the definitions and implications of the conduction angle in relation to the firing angle and the behavior of the circuit.
Discussion Character
- Technical explanation
- Conceptual clarification
- Debate/contested
Main Points Raised
- One participant asks for clarification on what the conduction angle (θ) physically represents in the context of a half-wave SCR rectifier.
- Another participant states that the SCR turns on at the conduction angle within a single period of 0 to 360 degrees.
- A different participant corrects this by asserting that the SCR is actually turned on at the firing angle (α).
- One participant clarifies the distinction between firing angle and conduction angle, explaining that θ represents the voltage/current phase angle due to the RL circuit, and that the SCR continues to conduct beyond the firing angle due to the inductor's collapsing field.
Areas of Agreement / Disagreement
There is no consensus on the definitions and implications of the conduction angle and firing angle, with multiple competing views presented by participants.
Contextual Notes
Participants express differing interpretations of the terms involved, particularly regarding the relationship between the firing angle and conduction angle, as well as the role of the RL load in the SCR operation.
- #2
meBigGuy
Gold Member
- 2,325
- 406
considering a single period to be 0 to 360 degrees, the scr turns on at the conduction angle.
- #3
buildingblocs
- 17
- 1
I thought the SCR is turned on at the firing angle (α).
- #4
buildingblocs
- 17
- 1
Below are the formulas that I am referring to:
Attachments
-
FireShot Screen Capture #014 - 'Microsoft Word - ECE3051_2008_exam_formula_doc - ECE3051_2008_ex.png -
FireShot Screen Capture #015 - 'Microsoft Word - ECE3051_2008_exam_formula_doc - ECE3051_2008_ex.png -
FireShot Screen Capture #016 - 'Microsoft Word - ECE3051_2008_exam_formula_doc - ECE3051_2008_ex.png
- #5
meBigGuy
Gold Member
- 2,325
- 406
OK, my bad. Firing angle is angle at which it starts conducting, conduction angle is angle over which it conducts.
But theta in the above circuit is the voltage/current phase angle caused by the RL circuit. The SCR is fired at α, but conducts beyond ∏ -α because of the inductor field collapsing, represented by theta. So it continues to conduct until ∏ + theta.
But theta in the above circuit is the voltage/current phase angle caused by the RL circuit. The SCR is fired at α, but conducts beyond ∏ -α because of the inductor field collapsing, represented by theta. So it continues to conduct until ∏ + theta.
Similar threads
- · Replies 18 ·
- · Replies 77 ·
- · Replies 15 ·
- · Replies 10 ·
- · Replies 1 ·
- · Replies 8 ·
- · Replies 10 ·