Process Control Systems Episode 7 ppsx

... its control systems ought never to interfere with this aspiration. Multivariable Process Control I 1 97 FIG 7. 7. The effect of m2 on cl de- pends on the ratio of their periods. Equation (7. 20) ... expanded in Chap. 7, Multivariable Process Control. But the deepest penetration into the 194 1 Multiple-loop Systems component blending system be as follows: am -I- bm (7....

Ngày tải lên: 12/08/2014, 16:21

... Feedback Control Since 72 = 2, n2 + n 4+2 3 zz-= 2 2 and 3: = (2.618)(0.382) = 1.00 With three capacities of time constant 7, Tl - = 5.0503 7 72 - = 0.6403 i- 73 . - = 0.3090 7 G.0000 and ... con- tribution of 71 is 45”. This occurs where 70 = 2 ~7~ . Here 135” of phase FIG 1.25. Zntegral control of dead time (aboue) is the same as propor- tional control of a dea...

Ngày tải lên: 12/08/2014, 16:21

... 0 125 -36 P 127r&, 158 220 361 llOTd/T, 1 27 196 22%,/T, 254 540 Process 70 Gain 4.OOsd 0.64rd/r, 4.80 0 .76 6.00 0.95 8.00 1. 27 -__ 3.197d 0.5 17& amp;1 4.00 0.64 5. 37 0.86 2.867d 0.45rJn 4.00 ... by Process I 1 ml -7- 7gg+ Controller , FIG 4.10. The complementary controller has a model of the process in its positive feedback loop. L l Linear Controllers 99 I loop. For...

Ngày tải lên: 12/08/2014, 16:21

... than one control loop. CASCADE CONTROL The output of one controller may be used to manipulate the set point of another. The two controllers are then said to be cascaded, one upon the other. Each controller ... prime variable. Secondary Controller Primary controller FIG 6.1. Cascade control resolves the process into two parts, each within a closed loop. 156 1 Multiple-loop Systems Th...

Ngày tải lên: 12/08/2014, 16:21

... Manipulated variable - c * Process Controlled variable * I I FIG 8.1. The control system embodies a for- ward flow of information. Feedforward Control I 223 MzY FIG 8. 17. The complete control system for ... given in Eq. (7. 16). Feedforward Control I PO7 feedforward system to force the process to respond as it was designed- to follow the set points as directed without regard to...

Ngày tải lên: 12/08/2014, 16:21

... The control system for once-through boiler must be as closely knit as the process itself. Control of Energy Transfer h P a Set boint to combustion- :ontrol system Set point to feedwater flow controller match ... the significance of the design procedures that follow will be lost. Alany processes can tolerate poorly designed control systems, particularly if they are protected from a...

Ngày tải lên: 12/08/2014, 16:21

... 206.2”F. lo.2 TT = -3 min; 70 = 4.8 min; P = 71 %. The loop is marginally stable. 10.3 71 9 = -7. 8 min; 70 = 4.3 min; P = 72 %. For the second calculation, TT = +lO min; 70 = 3.9 min; P = 65%. 342 ... similarity to the control equation for distillation-but in this 350 [ Appendix Chapter P 9.1 Noninteracting: 7, = 2 47, G, = 0.60. Interacting: 7, = 3 37, G...

Ngày tải lên: 12/08/2014, 16:21

... decoupling systems, 199 in feedforward systems, 219 Acids, ionization of, 275 - 277 Adaptation in feedforward-feedback systems, 223, 224 Adaptive control, 170 - 179 dividers in, 176 , 177 dynamic, 171 - 174 , ... 171 - 174 , 223 feedforward, 175 , 223-2 27 programmed, 172 self-adaptive, 173 , 176 - 179 steady-state, 174 - 179 , 225-2 27 Adiabatic drying, 344, 345 ex Adjusting contr...

Ngày tải lên: 12/08/2014, 16:21

... members of the review panel being independent. Design control 2 57 auto204.qxd 10/04/00 21:33 Page 2 57 Design procedures (4.4.1) Procedures to control the design (4.4.1) The standard requires the ... a process of choosing solutions from avail- able technologies. You may require two types of design control procedures, standards, and guides: those for controlling all designs and thos...

Ngày tải lên: 13/08/2014, 15:21