第一篇:西工大自動化專業英語三下重點短文
1、p94The transfer function can be obtained in several ways.One method is purely mathematical and consists of taking the Laplace transform of the differential equations describing the components or system and then solving for the transfer function;nonzero initial conditions, when they occur, are treated as additional inputs.A second method is experimental.A known input(sinusoids and steps are commonly used)is apply to the system, the output is measured, and the transfer function is constructed from operating data and combination of the known transfer functions of the individual elements.This combination or reduction process is termed block diagram algebra.2、p93 In Eq.(2-1B-2)the denominator D(s)of the transfer function is called the characteristic function since it contains all the physical characteristics of the system.The characteristic equation is formed by setting D(s)equal to zero.The roots of the characteristic equation determine the stability of the system and the general nature of the transient response to any input.The numerator polynomial N(s)is a function of how the input enters the system.Consequently, N(s)does,however, along with the specific input, determine the magnitude and sign of each transient mode and thus establishes the shape of the transient response as well as the steady-state value of the output.3、p94 The Laplace transformation comes from the area of operational mathematics and is extremely useful in the analysis and design of linear systems.Ordinary differential equations with constant coefficients transform into algebraic equations that can be used to implement the transfer function concept.Furthermore, the Laplace domain is a nice place in which to work, and transfer functions may be easily manipulated, modified, and analyzed.The designer quickly becomes adept in relating changes in the Laplace domain to behavior in the time domain without actually having to solve the system equations.When time domain solutions are required, the Laplace transform method is straightforward.The solution is complete, including both the homogeneous(transient)and particular(steady-state)solutions, and initial conditions are automatically included.Finally, it is easy to move from the Laplace domain into the frequency domain.4、p96 Analytical techniques require mathematical models.The transfer function is a convenient model form for the analysis and design of stationary linear systems with a limited number of differential equations and by block diagram algebra.From the deferential or intergro-differential equations describing the behavior of a particular plant, process, or component, using the Laplace transformation and its properties can develop the transfer functions.5、p97 The stability of a continuous or discrete-time system is determined by its response to inputs or disturbance.Intuitively, a stable system is one that remains at rest(or in equilibrium)unless excited by an external source and returns to rest if all excitation are removed.The output will pass through a transient phase and settle down to a steady-state response that will be of the same form as, or bounded by, the input.If we apply the same input to an unstable system, the output will never settle down to a steady-state phase;it will increase in an unbounded manner, usually exponentially or with oscillations of increasing amplitude.6、p97 Stability can be precisely defined in terms of the impulse responsey?(t)of a continuous system, or Kronecker delta responsey?(k)of a discrete-time system, as follows:
A continuous(discrete-time)system is stable if its impulse responsey?(t)(Kronecker delta responsey?(k))approaches zero as time approaches infinity.An acceptable system must at minimum satisfy the three basic criteria of stability, accuracy, and a satisfactory transient response.These three criteria are implied in the statement that an acceptable system must have a satisfactory time response to specified inputs and disturbances.So, although we work in the Laplace and frequency domains for convenience, we must be able to relate these two domains, at least qualitatively, to the time domain.7、p99 The Routh Criterion: All the roots of the characteristic equation have real parts if and only if the elements of the first column of the Routh table have the same sign.Otherwise, the number of roots with positive real parts is equal to the number of changes of sign.The Hurwitz criterion is another method for determining whether all the roots
of the characteristic equation of a continuous system have negative real parts.It has the same principle with the Routh criterion in substantial although their forms or patterns are different, so they are commonly called Routh-Hurwitz criterion.8、The three basic performance criteria for a control system are stability, acceptable steady-state accuracy, and an acceptable transient response.With the system transfer function known, the Routh-Hurwitz criterion will tell us whether or not a system is stable.If it is stable, the steady-state accuracy can be determined for various types of inputs.To determine the nature of the transient response, we need to know the location in the s plane of the roots of the characteristic equation.Unfortunately, the characteristic equation is normally unfactored and of high order.9、The root locus technique is a graphical method of dertermining the location of the roots of the characteristic equation as any single parameter, such as a gain or time constant, is varied from zero to infinity.The root locus, therefore, provides information not only as to the absolute stability of a system but also as to its degree of stability, which is another way of describing the nature of the transient response.If the system is unstable or has an unacceptable transient response, the root locus indicates possible ways to improve the response and is a convenient method of depicting qualitatively the effects of any such changes.10、If the part of the real axis between two o.l.poles(o.l.zeros)belongs to the loci, there must be a point of breakaway from, or arrival at, the real axis.If no other poles and zeros are close by, the breakaway point will be halfway.In Fig.2-3A-2d, adding the polep3pushes the breakaway point away;a zero at the position ofp3would similarly attract the breakaway point.11、The frequency transfer function of a system or of its KZ?j?P?j??function can be represented either by the single Nyquist diagram(a polar plot)or by plots of the amplitude ratio and the phase angle against the input(forcing)frequency.It is customary to plot the amplitude ratio in decibels and the phase angle in degrees against the common logarithm of the input frequency.In this form, the
two plots are known as Bode plots(after H.W.Bode).12、In Bode plots, the magnitude M in dB and the phase angle ? in degrees are plotted against ? on semilog paper.The development has shown the following:Bode magnitude and phase-angle plots of KZ?j?P?j?? are obtained by summing those of its elementary factors.These plot are much easier to make than polar plots or Nyquist diagrams, and can readily be interpreted in terms of different aspects of system performance.13、the plots are the mirror images of the corresponding integrator relative to the 0dB and 0?axes.This is also true for the leads corresponding to the simple and quadratic lag below.The asymptotes meet at the break frequency or corner frequency given by???1(or)on the normalized plot.14、Gain factor compensation: It is possible in some cases to satisfy all system specification by simple adjusting the open-loop gain factor K.Adjusting of the gain factor K does not affect the phase angle plot.It only shifts the magnitude plot up or down to correspond to the increase or decrease in K.15、Lead compensation: The addition of a cascade lead compensator to a system lowers the overall phase angle curve in the low-to-mid-frequency region.Lead compensation is normally used to increase the gain and/or phase margins of a system or increase its bandwidth.An additional modification of the Bode gain KB is usually required with lead networks.16、Lag compensation: The lag compensation is employed in some cases to decrease the bandwidth of the system, and it is also used to improve the relative stability for a given value of error constant, or to reject the noise of high-frequency.17、Lag-lead compensation: It is sometimes desirable to simultaneously employ both lead and lag compensation.Although one each of these two networks can be connected in series to achieve the desired effect, it is usually more
convenient to mechanize the combined lag-lead compensator.18、The transfer function can be obtained in several ways.One method is purely mathematical and consists of taking the Laplace transform of the differential equations describing the components or system and then solving for the transfer function;nonzero initial conditions, when they occur, are treated as additional inputs.A second method is experimental.A known input(sinusoids and steps are commonly used)is applied to the system, the output is measured, and the transfer function is constructed from operating data and curves.The transfer function for a subsystem or complete system is often obtained by proper combination of the known transfer functions of the individual elements.This combination or reduction process is termed block diagram algebra.19、Design of a feedback control system using Bode techniques entails shaping and reshaping the Bode magnitude and phase angle plots until the system specifications are satisfied.These specifications are most convenient expressed in terms of frequency-domain figures of merit such as gain and phase margin for the transient performance and the error constants for the steady-state time-domain response.And shaping the asymptotic Bode plots of continuous-time systems by cascade or feedback compensation is a relatively simple procedure.
第二篇:自動化專業英語重點
歐姆定律
Ohm’s law states that the voltage across the resistor is equal to the current through the resistor multiplied by the value of the resistance.法拉第定律
Faraday’s states that the voltage across the inductor is proportional to the rate of change with time of the current through the inductor.基爾霍夫第一定律
Kirchhoff’s first law states that the algebraic sum of the voltages around a closed loop is 0,or,in any closed loop, sum of the voltage rises must equal the sum of voltage drops.運放
The first law states that in normal op-amp circuits we may assume that the voltage difference between the input terminals is zero, that is, U+=U-.The second law states that in normal op-amp circuits both of the input currents may be assumed to be zero: I+=I-電路理論 theory of circuit
模擬電子技術analog electronics technology
數字電子技術digital electronics technology
電力電子技術power electronics technology
電磁場electromagnetic field
電機與拖動electric motor and electric drive
電力拖動自動控制系統electric drive automatic control system 自動控制理論automatic control theory
現代控制理論modern control theory
智能控制intelligent control
微機原理principle of microcomputer
計算機接口技術computer interface technology
計算機控制技術computer control technology
自動調節裝置automatic regulators
過程控制系統process control system
過程檢測及儀表process measurement and instrument
單片機原理與應用principle and application of single-chip computer 可編程序控制器系統programmable logical controller system 現場總線技術fieldbus technology
嵌入式系統embedded system
供電技術power supplying technology
計算機仿真computer simulation
信號分析與處理signal analyzing and processing
集散控制系統distributed control system
樓宇自動化building automation
機器人學robotics
GTOgate turn-off thyristor門極可關斷晶閘管 GJTbipolar junction transistor雙極結型晶體管 SCR
第三篇:自動化專業英語 考試 重點單詞
(一)單詞英譯漢
circuit components電路元件root mean square values 均方根值 Conductor導體effective value有效值
Wire導線sinusoidal time function正弦時間函數 Circuit diagram電路圖circuit parameters:電路參數 Voltage drop電壓降Time-invariant: 時不變的 Non-linear characteristic非線性特性Storage battery:蓄電池 ideal source理想電源Load characteristic:負載特性 ideal voltage source理想電壓源Terminal voltage:端電壓
ideal current source理想電流源Active circuit elements有源電路元件 potential電位
series and parallel equivalent circuit 串并聯等值電路
internal resistance 內阻
complex number 復數
vector 向量
absolute value 絕對值
complex peak value 復數幅值
rotating vector旋轉變量
logic circuit 邏輯電路
digital circuit 數字電路
chance variable 隨機變量
decimal number 十進制數
logic condition 邏輯狀態
output lead 輸出端
logic OR function 邏輯或函數
logic AND function 邏輯與電路
logic NOT function 邏輯非電路
logic NOR function 邏輯或非電路
an assembled circuit 集成電路
the processing, the storage and the transmission of information 信息處理、存儲和傳送
assembly cost 裝配成本
single chip microcomputer 單片機
process control過程控制
Microprocessor 微處理器
modular design 模塊化設計
interface 接口
manual supervision 手動操作
general-purpose elements 通用元件
the large scale integrated circuit — the silicon chip
大規模集成電路-硅片
software engineering 軟件工程
civilian use 民用
biometric security 生物識別安全系統
security alarm system 防盜報警系統
structured cabling 結構化布線
router 路由器
gateway 網關
ventilation 通風
air conditioning units 空調設備
illumination 照明
electron 電子
heating, ventilating, air conditioningand refrigeration 暖通空調制冷
protocol(數據傳遞的)協議
performance map性能圖
compressor 壓縮機
Micro-electromechanical Systems 微型機電系統 automated diagnostics 自動診斷
Intelligent Building智能建筑
smart home智能家居
Centralized management, decentralized control集中管理、分散控制
registers寄存器
analog circuit模擬電路
feedback 反饋
amplifier 放大器
actuator執行機構
regulate調節
Artificial intelligence人工智能
word recognition 文字識別
Adaptive Control自適應控制
telecommunication 電信
terminal 終端
water supply and discharge給排水
weak electricity弱電
architecture建筑學
manipulate 操作
office automation 辦公自動化
運算放大器 operational amplifier
addition加
subtraction減
multiplication乘
integration積分
single phase circuit 單相電路
transducer 傳感器HVAC&R
第四篇:自動化專業英語
1)the parameterization of the0controller0isC=X+MQ/Y-NQ。where N,M are right coprime factors of P,X,Y satisfy NX+MY=1,Q∈RH∞
2)According to the right coprime factorization of P, N=,M=,X=,Y=By the performance of the closed-loop system
N(0)[X(0)+M(0)Q(0)]=1 N(10j)[Y(10j)-N(10j)Q(10j)]=0,So take Q in the form Q(s)=x1+x2·1/s+1+x3·1/(x+
1)2
we can get the solution of Q。x1=,x2=,x3=,Q=Finally,the controller is C=
步驟:S=1-λ/λ代人 P(λ)=λ2/6λ2-5λ+1
X=-q2/r2 ,y=1+q1q2/r2 λ=1/s﹢1
N(S)=1/(s+1)2
M(s)=(s-1)(s-2)/(s+1)2 X(s)=19s-11/s+1Y(s)=s+6/s+1
C=X+MQ/Y-NQ
N(0)[X(0)+M(0)Q(0)]=1 N(10j)[Y(10j)-N(10j)Q(10j)]=0
Q(0)=6,Q(10j)=-94+70j Q(s)=x1+x2·1/s+1+x3·1/(x+
1)2
x1=-79 x2=-723 x3=808 Q(s)=(-79s2-881s+6)/(s+1)2C(s)=[-60s4-598s32
2+2515s-1794s+1]/[s(s+100)(s+9)]
A control system is stable if the number of encirclements of the(-1,0)point by the GH plot is equal to the number of poles of GH with positive real parts.The direction of encirclement must be in a direction opposite to τs.GH is on open loop transfer function.τs is open right half of s-plane.一個控制系統是穩定的數量是否包圍的(1,0)點的GH圖的數量相等的兩極與積極的真實部分GH。被包圍的方向都必須在一個τs的相反方向。
“GH”是在開環傳遞函數上。τs在s-plane的右半平面開放。
二.The process of designing a control system generally involves many steps.A typical scenario is as follows:
1.Study the system to be controlled and decide what types of sensors and actuators will be used and where they will be placed.2.Model the resulting system to be controlled.3.Simplify the model if necessary so that it is tractable.4.Analyze the resulting model;determine its properties.5.Decide on performance specifications.6.Decide on the type of controller to be used.7.Design a controller to meet the specs, if possible;if not, modify the specs or generalize the type of controller sought.8.Simulate the resulting controlled system, either on a computer or in a pilot plant.9.Repeat from step 1 if necessary.10.Choose hardware and software and implement the controller.11.Tune the controller on-line if necessary.r.reference or command inputvsensor outputuactuating signal, plant inputdexternal disturbanceyplant output and measured signaln.sensor noise
第五篇:西工大重點實驗室
凝固技術國家重點實驗室 材料學院 黃衛東
航空學院翼型、葉柵空氣動力學國家級重點實驗室
動力與能源學院 高正紅魚雷制導技術國家級重點實驗室 航海學院 宋保維
固體火箭發動機燃燒熱結構與內流場國家
級重點實驗室 航天學院 何國強無人機特種技術國家級重點實驗室 國防研究院 周洲 6 超高溫結構復合材料國家級重點實驗室 材料學院 成來飛 7
航天飛行動力學技術國家級重點實驗室 航天學院 袁建平