过程控制试卷

南京工业大学过程控制工程试题（ B ）卷（闭）2006—2007 学年第1学期使用班级自03 A方向

班级学号姓名

一、选择题：（1-6题为单选题每题3分，7-9题为多选题每题4分）[ ]1.T he behavior of the controlled variable, CV, is important because...

A It was selected to achieve one or more of the 7 control objectives.

B The sensor measures this value

C Large fluctuations create messy trend plots.

[ ]2.T he PID controller...

A is non-linear.

B is linear (obeys proportionality and superposition)

C obeys proportionality only.

D obeys superposition only.

[ ]3.W hich of the following statement(s) does NOT appear in the cascade control design criteria?

A The secondary variable must indicate the occurrence of an important disturbance.

B Only one valve can influence the secondary and primary variables.

C The secondary variable dynamics must be faster than the primary variable

dynamics

D There must be a causal relationship between the manipulated and secondary

variables.

[ ]4.W hich of the following statements are true for a valve positioner?

A It is a secondary in a cascade control system.

B It uses no measured variable.

C It can improve the control performance for a slow feedback control loop.

[ ]5.C ascade control involves two controlled variables, but only one valve.

A The description is not correct; cascade involves two controlled variables and two

valves.

B The description is not correct; cascade involves one controlled variable and one

valve.

C Cascade control involves two controlled variables, but only the primary variable is

controlled independently by the valve.

D The degrees of freedom principle does not apply to a system with two controllers. [ ]6.T he non-isothermal stirred tank chemical reactor is shown in the figure below.

We want to control AC-1. What

is the best cascade design for the

disturbances shown in the figure?

A AC-1 -> TC-1 -> vc

B AC-1 -> AC-2 -> vc

C AC-1 -> AC-2 -> va

[ ]7.T he three modes of the most common feedback controller are called the...

A Persistent

B Integral

C Proportional

D Derivative

E Interacting

F Disturbance

[ ]8.W hich of these control loop elements are typically very fast and very accurate

A Electrical Transmission

B Signal Conversion

C Process

D Final

Element, Valve

[ ]9.F or the cascade controller in the figure

the temperature controller can be referred

to as:

A Primary

B Top level

C secondary

D Outer