Author Topic: Polygon pour - sharp corners -> rounded corners  (Read 10880 times)

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Offline MandragoraTopic starter

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Polygon pour - sharp corners -> rounded corners
« on: December 27, 2016, 05:46:14 pm »
Hello Altium users, I am using AD 10.

I am designing HV PCB. Circuit is simple, it is half bridge made on SiC N mosfets switching 800V DC, PCB works as BUS BAR on internal layers.
To maximize cooper area from HB output to Wurth press fit terminal I've made rectangular polygon.

Polygon correctly keeps clearance from other HV points but in a result creates sharp corners (marked with black circles on the attachment). Such corners are very bad for HV aplication. Is there any solution to add a rule or something where corners have to be smoothed to at least 2mm radius? I haven't fount any options to set it.
Did any one of You had similar problem?

Regards,
Mandragora
 

Offline T3sl4co1l

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Re: Polygon pour - sharp corners -> rounded corners
« Reply #1 on: December 27, 2016, 08:27:27 pm »
Well, the points indicated at the bottom of the figure aren't contributing much if any conductance, so you can simply trim the polygon in that area.

There isn't a general "round corners" function.  The "remove narrow necks" option has some effect, but makes a straight line cut (and not always making a mitered corner).  If you must have rounded shapes, you're probably best off adding polygon cutouts with rounded perimeters (arc segments can be drawn by grabbing a segment midpoint and CTRL+SPACE to cycle segment type).  Don't forget to update their positions and angles after moving things around!

Tim
Seven Transistor Labs, LLC
Electronic design, from concept to prototype.
Bringing a project to life?  Send me a message!
 
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Re: Polygon pour - sharp corners -> rounded corners
« Reply #2 on: December 27, 2016, 10:13:34 pm »
Well, the points indicated at the bottom of the figure aren't contributing much if any conductance, so you can simply trim the polygon in that area.
Its the field concentration from sharp points that is the problem, clearance/creepage rules are generally assuming parallel or rounded conductors facing each other. For something that small where the poly fill isn't doing much you can route some thick traces by hand and use the rounded edge pours for the less important sections.
 


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