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Disturbance input

It is conventional to refer to the system being controlled as the plant, and this, as with other elements, is represented by a block diagram. Some inputs, the engineer will have direct control over, and can be used to control the plant outputs. These are known as control inputs. There are other inputs over which the engineer has no control, and these will tend to deflect the plant outputs from their desired values. These are called disturbance inputs. [Pg.4]

In the case of the ship shown in Figure 1.3, the rudder and engines are the control inputs, whose values can be adjusted to control certain outputs, for example heading and forward velocity. The wind, waves and current are disturbance inputs and will induce errors in the outputs (called controlled variables) of position, heading and forward velocity. In addition, the disturbances will introduce increased ship motion (roll, pitch and heave) which again is not desirable. [Pg.4]

A generalized closed-loop control system is shown in Figure 4.22. The control problem can be stated as The control action u t) will be such that the controlled output c t) will be equal to the reference input r t) for all values of time, irrespective of the value of the disturbance input riit) . [Pg.81]

Figure 9.18 shows a classical feedback control system D s) is a disturbance input, N s) is measurement noise, and therefore... [Pg.300]

In real life, we expect probable simultaneous reference and disturbance inputs. As far as analysis goes, the mathematics is much simpler if we consider one case at a time. In addition, either case shares the same closed-loop characteristic polynomial. Hence they should also share the same stability and dynamic response characteristics. Later when we talk about integral error criteria in controller design, there are minor differences, but not sufficient to justify analyzing a problem with simultaneous reference and load inputs. [Pg.90]

The controller setting is different depending on which error integral we minimize. Set point and disturbance inputs have different differential equations, and since the optimization calculation depends on the time-domain solution, the result will depend on the type of input. The closed-loop poles are the same, but the zeros, which affect the time-independent coefficients, are not. [Pg.107]

Figure 2.32 describes the responses of the individual control modes, and it also shows the responses of various mode combinations to a number of disturbance inputs. Similarly, Figure 2.33 shows the controller responses to set point step changes. [Pg.184]

The relationship between output, manipulated, and load variables constitutes the process control system of the dryer (see Eigure 57.1). In particular, the purpose of a dryer control system is to produce a desired output by changing the manipulated variables so as to compensate for changes in the main load variables (disturbances). Inputs are in the form of commands, which the output is expected to follow, and disturbances, which the automatic control is expected to minimize. [Pg.1155]

The inputs to a manufacturing system include production orders, raw material and labor, disturbance inputs, and ccmtrolled inputs. Production orders specify the quantities of various jobs to be processed and the dates on which these jobs are due. Disturbance inputs include machine failures and labor outages, over which the scheduler has little influence. Controlled inputs include scheduling, maintenance, and overtime decisirms, which the scheduler can regulate within bounds. The state of a manufacturing system defines the levels for all completed and partially completed jobs, the status of all machines, the availability of labor, and the inventories for aU materials. Outputs of the manufacturing system may be defined as any portion of the state - for example, the inventory levels of all jobs ready for shipment on a specified date as shown in Fig. 1 (Chryssolouris 2006). [Pg.996]

While one of the most critical factors that determines the performance of a servo system is the closed-loop bandwidth (Skogestad and Postlethwaite 2005) (i.e., active frequency range, within which disturbance inputs are successfully rejected and reference inputs are accurately followed), there are also important limitations that determine the achievable bandwidth in a servo system arising typically from the dynamics of the plant and controller such as unstable zeros and delays, umnodeled dynamics, vibration modes, actuator saturations, and... [Pg.1114]

From this equation, the respcmse H2(s) to ie disturbance input a (s) can be obtained. Fear the unit-st disturbance ii >ut < (s), se obtain... [Pg.29]

The cOosed-loop tremsfer function for the disturbance input... [Pg.156]

Tbe regulrenent on the response to the step disturbance input is that the reiponop ehould attenuate rapidly. Let us interpret this requizeemt to be the settling. tine of 2 sec. By a sinple MSTIAB trial-and-error approaA on the value o K,... [Pg.156]

Figure 5.11 shows a typical process, where the input is divided into two types manipulated variables and input disturbances. Input disturbances can be divided further, into measured and unmeasured disturbances. The output variables to be controlled are also divided into measured and unmeasured variables. [Pg.364]

Because A(t), B(t), and F(t) can have arbitrary time dependence, the fundamental matrix solution is usually obtained by numerical methods. Nevertheless, once (t, to) is determined, the solution x(t) may be readily calculated for a variety of control and disturbance inputs u(t) and d(t) using Eq. (A.52). [Pg.608]

Transfer functions G (s), G s) and their response functions from the setpoint input w and disturbance input z are clearly different. [Pg.138]

The simulation which is used to analyse the transient behaviour of the model can be divided in two types driver related inputs and external disturbances inputs. Driver s inputs will be in the propulsion system, either in acceleration or deceleration manoeuvres, and in the steering system, in cornering manoeuvre. External disturbances will consist of road vertical input. [Pg.206]


See other pages where Disturbance input is mentioned: [Pg.295]    [Pg.173]    [Pg.997]    [Pg.1114]    [Pg.1114]    [Pg.36]    [Pg.156]    [Pg.157]    [Pg.161]   
See also in sourсe #XX -- [ Pg.4 , Pg.5 ]




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Disturbance

First-Order Response to an Input Step-Change Disturbance

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