1 / 13

제어설계기법 실습 #6

제어설계기법 실습 #6. Frequency-domain properties. 실험실습 #6 안내서. 실험실습 번호 : #6 실험실습 일시 : 2011. . . 담당교수 :  담당조교 : , . 제목 : frequency-domain properties 목적 : bode plot 을 이용하여 control gain 으로 인한 system bandwidth 의 변화를 살펴본다 . 실습에 필요한 기초지식 : 슬라이드 유인물 참조

larya
Télécharger la présentation

제어설계기법 실습 #6

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 제어설계기법 실습 #6 Frequency-domain properties

  2. 실험실습 #6 안내서 • 실험실습 번호 : #6 • 실험실습 일시: 2011. . . • 담당교수 :  • 담당조교 : ,  제목 : frequency-domain properties 목적 : bode plot을 이용하여 control gain으로 인한 system bandwidth의 변화를 살펴본다. 실습에 필요한 기초지식 : 슬라이드 유인물 참조 실습절차 : 슬라이드 유인물 참조

  3. Frequency-domain properties • Specifications of frequency-domain • Resonant peak • Maximum value of • Indication on the relative stability of a stable closed-loop system • Large corresponds to a large maximum overshoot of the step response. • Resonant frequency • Frequency at which the peak resonance occurs. • Bandwidth BW • Frequency at which drops to 70.7 percent of, or 3dB down from, its zero-frequency value. • Indication on the transient-response properties in the time domain.

  4. Bandwidth properties • Bandwidth properties • Larger BW makes higher-frequency signals are more easily passed through the system. • Smaller BW makes only signals of relatively low frequencies are passed, and the time response will be slow and sluggish. • BW and rise time are inversely proportional. • larger the bandwidth, faster the system will respond. • Rising time , increasing increases BW and decreases • Increasing decreases BW and increases

  5. Control gain & BW • example) relationship of control gain and BW

  6. Control gain & BW • Find the BW in magnitude graph(gain=1) BW=7.63

  7. Control gain & BW • decreased gain is applied (gain=0.1) BW=1.36 • increased gain is applied (gain=10) BW=24.9

  8. System stability margin • Phase margin & gain margin • Phase margin • Gain margin

  9. Check the stability margin in bode plot Bode plot example in MATLAB Bode plot result Gain margin 14.82 dB Phase margin 31.72°

  10. Computing the stability margin Stability margin (gain and phase margins) *gm have to be changed by dB unit. Example

  11. Computing the stability margin Gain margin 35.98 dB Phase margin 74.19°

  12. 1) 다음 G(s)는 unity feedback system의 forward-path transfer function 이다. k=1일 때의 bode plot을 수행하여 margin 값을 확인하고 시스템이 안정한지 확인하시오. 그리고 BW 값을 구하시오 2) 1번의 시스템이 안정하지 않다면, root-locus를 이용하여 적절한 damping ratio(0.707)값을 갖는 k값을 구하시오. Matlab 실험·실습과제6

  13. 3) 1, 2번의 결과를 이용하여 다시 bode plot을 그려 gain margin, phase margin, 그리고 각각의 crossover point를 구하시오. 그리고 BW를 구하여 1번과 비교한 후 추정할 수 있는 시스템 특성 변화를 설명하시오. Matlab 실험·실습과제6

More Related