Journal of Korean Society on Water Environment (한국물환경학회지)

Korean Society on Water Environment (한국물환경학회)
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Comparison of Proportional, Integral, and P-I Control Systems in Biological Wastewater Treatment Plants

생물학적 하수처리시스템에 적용된 Proportional, Integral 및 P-I 조절 시스템에 대한 비교

  • Kim, Sungpyo (Department of Civil, Structural, and Environmental Engineering, State University of New York at Buffalo)
  • 김성표 (뉴욕 주립 대 버펄로 대학 토목, 구조, 환경공학과)
  • Received : 2005.04.28
  • Accepted : 2005.06.03
  • Published : 2005.07.30
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Abstract

The main purpose of this study is to evaluate the characteristics of three sets of traditional control methods (proportional, integral, and proportional - integral controls) through lab-scale biological reactor experiments. An increase in proportional gain ($K_c$) resulted in reduced dissolved oxygen (DO) offset under proportional control. An increase in integral time ($T_i$) resulted in a slower response in DO concentration with less oscillation, but took longer to get to the set point. P-I control showed more stable and efficient control of DO and airflow rates compared to either proportional control or integral control. Developed P-I control system was successfully applied to lab-scale Sequencing Batch Reactor (SBR) for treating industrial wastewater with high organic strength.

Keywords

References

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