ECE 456556 System Modeling Mo Yuen Chow North Carolina State University All

# Ece 456556 system modeling mo yuen chow north

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ECE 456/556 - System Modeling© Mo-Yuen Chow, North Carolina State University, All Rights Reserved11Different Damping ConditionsUn-damped condition= 0Over-damped condition> 1Critically Damped condition= 1Under-damped condition< 1
Typical form of the response of an under-damped second-order system to a step inputRise time, trPeak time, tpOvershoot, MpSettling time, tsECE 456/556 - System Modeling© Mo-Yuen Chow, North Carolina State University, All Rights Reserved13Performance Measures for Second-Order SystemsLink:
Performance Measures for Second-Order Systems – cont’ECE 456/556 - Control© Mo-Yuen Chow, North Carolina State University, All Rights Reserved14Step ResponseTime (sec)Amplitude024681012141600.20.40.60.811.21.4tsMptrtd0.9 0.5 0.1 Allowabletolerance 2% or 5%
ECE 456/556 - Control© Mo-Yuen Chow, North Carolina State University, All Rights Reserved15Control modes1 The bang-bang(two-step)mode 2 The proportional mode (P) 3 The derivative mode (D) 4 The integral mode (I)   Pu tK e t  PU sK E s  Dde tu tKdt  DU sK sE s  Iu tKe t dt  IE sUsKs
ECE 456/556 - Control© Mo-Yuen Chow, North Carolina State University, All Rights Reserved16Combinations of modesProportional plus derivative modes (PD), Proportional plus integral modes (PI), Proportional plus integral plus derivative modes (PID). The term three-term controller is used for PID control. U1PGainKP1sIGainKIdu/dtDGainKDE1