week 17 digital control sytem
TRANSCRIPT
Professor Charlton S. Inao Control System Engineering-PE -3032
Defence University College of Engineering
Bishoftu, Ethiopia
Week 17
Digital Control System
Instructional Objectives To explain and understand the following
concept:
Digital Control System Sampling Process Intro to Z transform
Introduction to Digital
Control System
Digital Control System
Number System Decimal Binary BCD Octal Hexadecimal0 0000 0000 0000 0 01 0001 0000 0001 1 12 0010 0000 0010 2 23 0011 0000 0011 3 34 0100 0000 0100 4 45 0101 0000 0101 5 56 0110 0000 0110 6 67 0111 0000 0111 7 78 1000 0000 1000 10 89 1001 0000 1001 11 910 1010 0001 0000 12 A11 1011 0001 0001 13 B12 1100 0001 0010 14 C13 1101 0001 0011 15 D14 1110 0001 0100 16 E15 1111 0001 0101 17 F
Digital Signal
A digital signal is a physical signal that is a representation of a sequence of discrete values (a quantified discrete-time signal), for example of arbitrary bit stream, or of a digitized (sampled and analog-to-digital converted) analog signal. The term digital signal can refer to a continuous-time waveform signal used in any form of digital communication.
A pulse train signal that switches between a discrete number of voltage levels or levels of light intensity, also known as a a line coded signal, for example a signal found in digital electronics or in serial communications using digital baseband transmissionin, or a pulse code modulation (PCM) representation of a digitized analog signal.
A signal that is generated by means of a digital modulation method (digital passband transmission), produced by a modem, is in the first case considered as a digital signal, and in the second case as converted to an analog signal.
Analog/Continuous Signals
Example of analog and digital
Exercise
Advantages of Digital Signals• The main advantage of digital signals over analog
signals is that the precise signal level of the digital signal is not vital.
• This means that digital signals are fairly immune to the imperfections of real electronic systems which tend to spoil analog signals.
• Reduced cost• Flexibility in response to design changes• Noise immunity• Easy to control and manipulate
Digital Control System
Data Acquisition/Sampling
• Data acquisition is the process of sampling signals that measure real world physical conditions and converting the resulting samples into digital numeric values that can be manipulated by a computer.
• Data acquisition systems (abbreviated with the acronym DAS or DAQ) typically convert analog waveforms into digital values for processing.
The components of data acquisition systems include:
• Sensors that convert physical parameters to electrical signals.
• Signal conditioning circuitry to convert sensor signals into a form that can be converted to digital values.
• Analog-to-digital converters, which convert conditioned sensor signals to digital values.
Analog to Digital Conversion
Analog to digital
Analog to digital- digital to analog
Sampling Process
Sampling Process Theory
The Z Transform
Example Long Division Method
Solution
Sample problem
Solution
Sample Problem
Solution
Matlab samples for continuous and discrete
The EndThank You Very Much