FTA (Fault Tree Analysis, ๊ณ ์žฅ์ˆ˜๋ชฉ๋ถ„์„)

 

์ฒ ์ €ํ•œ ์•ˆ์ „์„ฑ

์ค‘์š”ํ•œ ์‹œ์Šคํ…œ ๋ฐ ์ œํ’ˆ์—๋Š” ์‹ฌ๊ฐํ•œ ์•ˆ์ „์‚ฌ๊ณ ๋ฅผ ๋ฐฉ์ง€ํ•˜๊ธฐ ์œ„ํ•ด ๋ฐฉ์–ด๋ฒฝ, ๋‚ด๊ฒฐํ•จ์„ฑ (Fault-tolerance), ๋‹ค์ค‘ํ™” ์š”์†Œ๋ฅผ ๊ตฌ๋น„ํ•œ ๊ฒฝ์šฐ๊ฐ€ ๋งŽ์Šต๋‹ˆ๋‹ค. ์•ˆ์ „์‚ฌ๊ณ ์˜ ๋ฐœ์ƒ ํ™•๋ฅ ์„ ๊ณ„์‚ฐํ•˜๋ ค๋ฉด ํ•˜์œ„ ์‚ฌ๊ณ  ์กฐํ•ฉ์„ ๊ณ ๋ คํ•ด์•ผ ํ•ฉ๋‹ˆ๋‹ค.

BQR์˜ Fault Tree Analysis ์†Œํ”„ํŠธ์›จ์–ด๋Š” ๋ณต์žกํ•œ ์‹œ๋‚˜๋ฆฌ์˜ค๋ฅผ ๋น ๋ฅด๊ณ  ์ •ํ™•ํ•˜๊ฒŒ ๋ถ„์„ํ•˜์—ฌ ์•ˆ์ „ ์ด๋ฒคํŠธ์˜ ๋™์ธ์— ๋Œ€ํ•œ ๊นŠ์€ ํ†ต์ฐฐ๋ ฅ์„ ์ œ๊ณตํ•ฉ๋‹ˆ๋‹ค.

 

ํšจ๊ณผ

  • ์‹ฌ๊ฐํ•œ ์ œํ’ˆ ๊ณ ์žฅ์‚ฌ๊ฑด ์ €๊ฐ ๋ฐ ์ž„๋ฌด ์‹ ๋ขฐ์„ฑ ํ–ฅ์ƒ
  • ์ •ํ™•ํ•˜๊ณ  ๋น ๋ฅธ ๊ณ„์‚ฐ

  • ์ดˆ๊ธฐ ๋ชจ๋ธ์— FMECA ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค ์‚ฌ์šฉ

BQR์˜ ๊ฒฐํ•จ ํŠธ๋ฆฌ ๋ถ„์„ ์†Œํ”„ํŠธ์›จ์–ด๋Š” IEC 61025 ํ‘œ์ค€์„ ์ค€์ˆ˜ํ•ฉ๋‹ˆ๋‹ค.

FTA traditional view
์ผ๋ฐ˜์ ์ธ FTA ๊ตฌ์กฐ

๋™์ž‘ ์›๋ฆฌ

BQR์˜ FTA ์†Œํ”„ํŠธ์›จ์–ด๋ฅผ ์‚ฌ์šฉํ•œ ๋ถ„์„ ์ ˆ์ฐจ

1) ๊ฐ€์ ธ์˜ค๊ธฐ

  • BQR์˜ ํ•ต์‹ฌ ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ BQR์˜ FMECA ๋ชจ๋“ˆ์—์„œ ๊ณ ์žฅ์œ ํ˜•, ์˜ํ–ฅ ๋ฐ ๋น„์œจ ๊ฐ€์ ธ์˜ด

2) ์‚ฌ์šฉ์ž ์ž…๋ ฅ

  • ์ž„๋ฌด ์‹œ๊ฐ„ ์ •์˜
  • ๊ณ ์žฅ์œ ํ˜•, ๊ณ ์žฅ๋ฅ  ๋ฐ ์˜ํ–ฅ ์ถ”๊ฐ€ (์ดˆ๊ธฐ ๋ฐ์ดํ„ฐ๋ฅผ ๊ฐ€์ ธ์˜จ ๊ฒฝ์šฐ ์ด ๋‹จ๊ณ„ ์ƒ๋žต)
  • ์•…์ฒœํ›„ ๋˜๋Š” ์ธ์  ์˜ค๋ฅ˜์™€ ๊ฐ™์€ ์ถ”๊ฐ€ ์™ธ๋ถ€ ์‚ฌ๊ฑด ์ถ”๊ฐ€
  • ๊ฒŒ์ดํŠธ ์œ ํ˜• ์ •์˜ (ํ•˜์œ„ ์ด๋ฒคํŠธ ๊ฐ„์˜ ๋…ผ๋ฆฌ์  ๊ด€๊ณ„)
  • ํŠน์ • ์ž„๋ฌด์‹œ๊ฐ„ ๋ฐ ๊ณตํ†ต์›์ธ ์ •์˜
Fault Tree Analysis software - screenshot
๋…ผ๋ฆฌ ๊ฒŒ์ดํŠธ ๋ฐ ์ด๋ฒคํŠธ ์œ ํ˜•

3) ๋ถ„์„

  • ์ •์ƒ์‚ฌ๊ฑด ํ™•๋ฅ  ๋ถ„์„
  • ์ตœ์†Œ๋‹จ์ ˆ์ง‘ํ•ฉ(Minimal Cut Set) โ€“ ์ •์ƒ์‚ฌ๊ฑด(Top Event)๋ฅผ ์œ ๋ฐœํ•˜๋Š” ์ตœ์†Œํ•œ์˜ ์‚ฌ๊ฑด๋“ค ์กฐํ•ฉ
  • ๋ฏผ๊ฐ๋„๋ถ„์„(Sensitivity Analysis): ๋ฏผ์ฃผ์š” ๊ณ ์žฅ์›์ธ ํŒŒ์•…

4) ๋ณด๊ณ ์„œ

  • ์ •์ƒ์‚ฌ๊ฑด ํ™•๋ฅ  ๋ถ„์„
  • ์ตœ์†Œ๋‹จ์ ˆ์ง‘ํ•ฉ(Minimal Cut Sets) ๋ชฉ๋ก
  • ๋ฏผ๊ฐ๋„๋ถ„์„(Sensitivity Analysis) ์ œ๊ณต
  • Excel, HTML ๋˜๋Š” Word ํŒŒ์ผ ํ˜•ํƒœ๋กœ ์ €์žฅ
Fault Tree Analysis software - screenshot 2
๊ณ„์ธต๊ตฌ์กฐ ํ‘œ์‹œ ์˜ˆ

๊ฒฐํ•จ ์ˆ˜๋ชฉ ๋ถ„์„ ์†Œํ”„ํŠธ์›จ์–ด ๊ธฐ๋Šฅ

  • ๋‹ค์–‘ํ•œ ๊ฒŒ์ดํŠธ ์œ ํ˜• ์ œ๊ณต : OR, AND, K out of N, Standby, AND Priority, NOT ๋ฐ XOR
  • ๋ณต์žกํ•œ ์‚ฌ๋ก€ ๋ถ„์„์— ์‚ฌ์šฉ๋˜๋Š” ์ด์ง„ ๊ฒฐ์ • ๋‹ค์ด์–ด๊ทธ๋žจ (BDD, Binary Decision Diagram) ์ œ๊ณต
  • ์ตœ์†Œ๋‹จ์ ˆ์ง‘ํ•ฉ ๋ถ„์„ ์ œ๊ณต
  • ๋ฏผ๊ฐ๋„๋ถ„์„(Sensitivity Analysis) ์ œ๊ณต
  • ๋‹ค์–‘ํ•œ ๋ณต๊ตฌ ์œ ํ˜• ๋ฐ ๊ฒ€์‚ฌ ๋ชจ๋ธ๋ง ๊ฐ€๋Šฅ