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222116610_2 Assiment.pptx

  1. Professor Dr. M.D Taufik Sir Rahul Das Vairagi
  2. Instructional Objectives In this presentation, the students shall be able to understand the principle of Signal Conditioning focusing mainly on the following topics: 1. Signal Conditioning 2. Data Acquisition 3. Microprocessor 4. Microcontroller 5. Electric Drive •
  3. Signal conditioning:  Signal conditioning is a process of data acquisition, and an instrument called a signal conditioner is used to perform this process. This instrument converts one type of electrical or mechanical signal (input- signal) into another (output-signal).  The purpose is to amplify and convert this signal into an easy to read and compatible form for data-acquisition or machine-control.  A signal conditioner helps to provide precise measurements, which are essential for accurate data acquisition and machine-control. These instruments can perform an additional number of different functions.
  4. Signal conditioning process:  Many applications require environment or structural measurements, such as temperature and vibration, from sensors. These sensors, in turn, require signal conditioning before a data acquisition device can effectively and accurately measure the signal.  Key signal conditioning technologies provide distinct enhancements to both the performance and accuracy of data acquisition systems.
  5. General structure of measurement system: The first component of a measurement system is the sensor that converts the physical variable to be measured into an electrical quantity. However, the signal is usually in a format that cannot be directly used: it requires ‘conditioning’.
  6. Contd..  The second part of any measurement system is the signal conditioning component that converts the electrical signal from an unsuitable format to a suitable format. Signal processing further modifies the signal to prepare it for transmission.  Signal conditioning element takes the output of the sensing element and converts it into a form more suitable for further processing, usually a d.c. voltage, d.c. current or frequency signal.
  7. Data Acquisition .1 Methodology 1.1 Source 1.2 Signals .2DAQ hardware .3 DAQ software
  8. Data Acquisition  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.
  9. Data Acquisition System The collection of hardware and software components that enable a computer to receive physical signals.
  10. 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.
  11. Microprocessors in Metrology 1
  12. The microprocessor is a multipurpose, programmable device that accepts digital data as input, processes it according to instructions stored in its memory, and provides results as output. What is Microprocessor? 2
  13. Let us Know: Micro-processors Vs. Micro-controller 3
  14. □ The application of microprocessor to metrology field has resulted in an extensive range of digital measuring instruments combining accuracy and ease of use □ A micro-processor can remove the tedious work and risk of error. □ Microprocessors can handle very complex measurements with no reduction in accuracy □ It provides process dimensional gauging with adaptive feedback Why Micro-processor is necessary? 1 5
  15. □ The processor improves set up procedures. For example, minimize misalignment of the measuring system. □ A microprocessor can log errors at high speed onthefly, and then remove setup errors using mathematical techniques. □ Automatic correction of systematic errors can be performed within a measuring system in realtime. □ The microprocessor also makes it possible to operate in realtime within a machining process, providing inprocess dimensional gauging 1 6 Contd..
  16. Hardware Required •A processing system composed of a microprocessor, with a readonly memory containing the operating system, and a memory containing the application program and variables. •An interface with the operator composed of a keyboard, screen display signal lamps, etc. •An interface to measure the lengths, etc. •Interface with different peripherals such as a printer, another computer, mass memory etc. 1 7
  17. Softwares used Basic software (operating software). It allows access to different resources of the system by means of simple and well defined orders. These orders constitute the part accessible to the programmer who can also work in high levellanguages. Eg- PolyWorks - The Universal 3D Metrology Software TM 1 8
  18. Signals from transducers Compare measurement with nominal values Display on a screen Input 19 Processing Output Flowchart
  20. Advantages: □ High accuracy □ Low measuring time □ On-line monitoring □ In-line monitoring □ Error logging is possible Disadvantages: □ High initial investment □ Skilled person is required Advantages and Disadvantages 21
  21. □ Rapid prototyping in plastic and metal for function, fitment and visualization. □ 3D surface modeling class A and class B. □ CMM part programming. □ Conversion of 2D drawing into 3D CAD model. □ CMM retrofit and calibration services. □ Product designing. □ 3D Solid Modeling □ Tool and die designing Applications 22
  22. Лектор: Розробники: Для студентів напрямів підготовки: Доступне для завантаження на сайті кафедри: Fundamentals of electric drive Electrotechnic faculty Electric drive department
  23. Basic concepts and determinations 1. Electric drive and its basic elements 2. Classification of electric drives 3. Basic directions of electric drive development
  24. Basic concepts and determinations Electric drive and its basic elements
  25. Electric drive and its basic elements Feedback signals Motor Three-phase transmission line Controller Convertor Gear box Transducer Transducer Transducer Reference signals Reference signals Feedback signals Feedback signals
  26. Types of electric motors ac motor dc motor Synchronous motor Function: transformation of electric energy into mechanical
  27. Types of Servo Motors  Servo motors are classified into different types based on their application, such as AC servo motor, DC servo motor, brushless DC servo motor, positional rotation, continuous rotation and linear servo motor etc.  Typical servo motors comprise of three wires namely, power control and ground.  The shape and size of these motors depend on their applications.  Servo motor is the most common type which is used in hobby applications, robotics due to their simplicity, affordability and reliability of control by microprocessors.
  28. AC motor Rotor Stator C1 B1 A1 A1 C2 B2 C1 A1 A1 B2 E= − 𝒅 𝒅𝒕 =kr
  29. Servo Motor:  The servo motor is most commonly used for high technology devices in the industrial application like automation technology.  It is a self contained electrical device, that rotate parts of a machine with high efficiency and great precision.  The output shaft of this motor can be moved to a particular angle.  Servo motors are mainly used in home electronics, toys, cars, airplanes, etc.
  30. AC Servo Motor AC servo motor is an AC motor that includes encoder is used with controllers for giving closed loop control and feedback. This motor can be placed to high accuracy and also controlled precisely as compulsory for the applications. Frequently these motors have higher designs of tolerance or better bearings and some simple designs also use higher voltages in order to accomplish greater torque. Applications of an AC motor mainly involve in automation, robotics, CNC machinery, and other applications a high level of precision and needful versatility.
  31. DC motor Stator Armature S N Br 2 Br 1 C1 C2 F2 F1 S N T 𝑭 = 𝑩𝑰𝑳 𝑩 - induction 𝑰 - current 𝑳 – length of the conductor T= 𝑭𝑫 T - torque 𝑭 - force 𝑫 - diamete
  32. DC Servo Motor  The motor which is used as a DC servo motor generally have a separate DC source in the field of winding & armature winding.  The control can be archived either by controlling the armature current or field current.  Field control includes some particular advantages over armature control.  In the same way armature control includes some advantages over field control.  Based on the applications the control should be applied to the DC servo motor.  DC servo motor provides very accurate and also fast respond to start or stop command signals due to the low armature inductive reactance.  DC servo motors are used in similar equipment's and computerized numerically controlled machines.
  33. Synchronous motor with permanent magnets Synchronous motor Synchronous motor with exiting winding
  34. Stepper Motor:  A stepper motor is an electromechanical device it converts electrical power into mechanical power.  Also it is a brushless, synchronous electric motor that can divide a full rotation into an expansive number of steps.  The motor’s position can be controlled accurately without any feedback mechanism, as long as the motor is carefully sized to the application.  Stepper motors are similar to switched reluctance motors.
  35.  The stepper motor uses the theory of operation for magnets to make the motor shaft turn a precise distance when a pulse of electricity is provided.  The stator has eight poles, and the rotor has six poles. The rotor will require 24 pulses of electricity to move the 24 steps to make one complete revolution.  Another way to say this is that the rotor will move precisely 15° for each pulse of electricity that the motor receives.
  36. Working Principle:  Stepper motors operate differently from DC brush motors, which rotate when voltage is applied to their terminals.  Stepper motors, on the other hand, effectively have multiple toothed electromagnets arranged around a central gear-shaped piece of iron.  The electromagnets are energized by an external control circuit, for example a microcontroller.  To make the motor shaft turn, first one electromagnet is given power, which makes the gear’s teeth magnetically attracted to the electromagnet’s teeth.  The point when the gear’s teeth are thus aligned to the first electromagnet, they are slightly offset from the next electromagnet.  So when the next electromagnet is turned ON and the first is turned OFF, the gear rotates slightly to align with the next one and from there the process is repeated.
  37.  Each of those slight rotations is called a step, with an integer number of steps making a full rotation.  In that way, the motor can be turned by a precise. Stepper motor doesn’t rotate continuously, they rotate in steps.  There are 4 coils with 90o angle between each other fixed on the stator. The stepper motor connections are determined by the way the coils are interconnected.  In stepper motor, the coils are not connected together. The motor has 90o rotation step with the coils being energized in a cyclic order, determining the shaft rotation direction.  The working of this motor is shown by operating the switch. The coils are activated in series in 1 sec intervals. The shaft rotates 90o each time the next coil is activated. Its low speed torque will vary directly with current.
  38. Rectifier Converters Inverter Function: conversion of electrical energy of one type into electrical energy of another type
  39. Transducers Function: conversion of signals of various nature into standard electrical signals
  40. Controllers Function: equipping machine-tools with control and automation functions • industrial PC (IPC), • programmable logic controller (PLC), • programmable automation controller (PAC)
  41. Basic concepts and determinations Classification of electric drives
  42. Classification of electric drives By the sort of current of drive engine:  direct current (DC)  alternating current (AC)
  43. Classification of electric drives By the sort of mechanical transmission:  geared electric drive in which an electric motor is connected with a working machine by means of one of types of transmission devices  gearless electric drive (direct drive), when an electric motor is connected directly with a machine tool Gear box Motor
  44. Forcer Permanent Magnet Classification of electric drives  By the type of motion:  unidirectional and reversing rotating  unidirectional and reversing linear motion Linear motion
  45. Classification of electric drives  By the level of automation: a) uncontrolled electric drive b) automated electric drive in which a part of control operations is executed without operator participation; c) automatic electric drive, in which full control operations are executed without operator participation. TRANSDUC ERS TRANSDU ERS a) b) c)
  46. Classification of electric drives  By the type of control system: a) open-loop control. It is an electric drive control system in which a feed-back of output coordinate absents; b) closed-loop control. It is an electric drive control system in which a feed-back of output coordinate presents; c) electric shaft  it is an interconnected electric drive which provides synchronous motion two or more machine tools, not having a mechanical connection. TRANSDUC ERS a) b) c)
  47. Classification of electric drives a) b) d)  By principles of output coordinates control: a) controllable electric drive which provides a guided change of machine tool motion coordinates in accordance with requirements of a technological process; b) positional electric drive which provides a machine tool transferring to a set position; c) follow-up electric drive which provides a machine tool moving in accordance with an arbitrarily changing reference signal; d) software programmable electric drive which provides a machine tool moving in accordance with a set program; e) adaptive electric drive which automatically adapts to parameters changing and disturbance influences, by a structure and parameters changing of a control system. ED MT  r ED MT  r ED MT (t) r(t) ED MT r,r c) ED MT (t) r TL(t) e)
  48. Classification of electric drives a) b) d) ED MT  r ED M1 M2 M3 MT  r c)  By a method of passing to mechanical energy: a) individual electric drive  only one machine tool is operated by one engine; b) group electric drive  a few machine tools are operated by one engine; c) multimotor electric drive  one machine tool is operated by a few electric motors; d) interconnected electric drive  an electric drive contains two or a few electric or mechanically connected electric drives, during working of which a set correlation of their speeds, loadings or positions of machine tools is supported. ED  r MT1 MT2 MT3 MT  r ED1 ED2 ED3
  49. Basic concepts and determinations Basic directions of electric drive development
  50. Basic directions of electric drive development  Expansion of automated drives, mainly frequency controlled drives of alternating current with a usage of the fully controlled semiconductor devices  Increase of requirements to accuracy indexes of dynamic and static modes of operations  Expansion and complication of electric drives functions  Standardization of an element base and creation of a complete electric drive for requirements satisfying of a wide class of production mechanisms  Expansion of power ratings to ten of thousands of kilowatts and considerable variety of their design  Creation of powerful gearless drives of ball and autogenous mills, mine winder, basic mechanisms of excavators and other mechanisms  Increase efficiency and power factor of all electric drive types  Usage of grouped electric drive systems with a common suppaly for flexible control of electric power streams, energy storage, reactive power compensation etc.
  51. Thank you 52