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Motor Control
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Electrical motors operate on
the principle that two magnetic fields within certain prescribed
areas react upon each other.
- cncKITS.com
Tutorial & FAQ - information on comuter control
- Control.com
- an automation and control site with a large discussion area,
and motors/motion are popular topics
- DSPs
excel in motor-control applications - motor control is a new
application for DSPs that can help to lower motor costs, give
better reliability and make them consume less energy
- How
Electric Motors Work - Electric motors are everywhere! In
your house, almost every mechanical movement that you see around
you is caused by an AC or DC electric motor. By understanding
how a motor works you can learn a lot about magnets,
electromagnets and electricity in general. In this edition of
HowStuffWorks you will learn what makes electric motors tick.
- Electric
Motor Terminology
- How
Electric Motors Work - Electric motors are everywhere! In
your house, almost every mechanical movement that you see around
you is caused by an AC or DC electric motor. By understanding
how a motor works you can learn a lot about magnets,
electromagnets and electricity in general.
- Information
about different surge suppression devices - motors are
inductive and can cause voltage surges
- Inside
an Electric Motor
- Introduction
To Linear Motors - A Linear Induction Motor (LIM) is
basically a rotating squirrel cage induction motor opened out
flat. Instead of producing rotary torque from a cylindrical
machine it produces linear force from a flat one. Applications
are many and varied, ranging from simple sliding doors to full
control of a ten tonne vehicle.
- Motioncontrol.com
- This Motor and Motion Control Portal has a direct path for the
engineers to find motion control manufacturers and their
products.
- Noise
in audio/video & R/C systems - noise can be caused by a
number of things including poor power ground schemes and poor
power distribution
- Questions
and aswers on electric motors and magnetics
- The
difference between Stepper Motors, Servos, and RC Servos
- The
rise of VSR motors - Once obscure,
variable-switched-reluctance motors are now entering mainstream
use from jet fighters to washing machines.
- 3
phase A.C. Motor Windings and Connection
- AC
Induction Motor Designs, Types - Worldwide popularity of ac
induction motors in numerous applications has led to some
standardized motor designs. The National Electrical Manufacturers
Association, (NEMA, Washington, D.C.) has developed specifications
for so-called NEMA design A, B, C, and D motor types. These
designs are based on standardizing certain motor characteristics
such as starting current, slip, and specified torque points. This
article is a brief rundown on NEMA motor types.
- Alex's
Electronic Resource on motors and accessories - This site had
many useful documents on electric motors.
- Anatomy
of an ac induction motor
- Basic
Motor Control Schematics
- Control
by a triack for an inductive load - application note AN308
from SGS-Thomson
- Controller
provides multimode phase control - inexpensive 16C508
multichip controller can implement a phase controller that
provides a two-key, indexed processor for ac power or other
discrete, digital-signal applications
- Dimmer
with AC motor? - Normal light dimmers may have some problems
with an inductive load, such as a motor. Essentially, the dimmer
works by chopping bits out of the AC waveform. Inductors, like the
coils in a motor, dislike having the current through them changed
abruptly, and produce large voltage spikes which can cause the
triac to self-trigger or burn if not properly taken care of. This
article tells how to do this.
- Generate
advanced PWM signals using 8-bit ตCs - hot to generate
waveforms needed for variable speed three phase motor controlling
- Identifying
Motor Defects Through Fault Zone Analysis - This article has
information on three phase AC motor troubleshooting and measuring.
- Motor
Controlling Application Notes from LSI Computer Systems
- Motor
Formulas - check also other useful
formulas
- Motor
Starter Basics - The first purpose of a motor controller is to
start and stop the equipment. A magnetic contactor provides the
traditional and still most common start-stop control. Protection
must be provided to prevent motor thermal damage due to high
currents caused by mechanical overloads. Overload relays in motor
controllers are connected in the motor current circuit between the
contactor and the motor. They are provided with three
current-sensing elements, one per phase, and a control contact,
which is wired to open the contactor. Relay operation includes an
inverse time characteristic; the higher the magnitude of an
overload, the shorter the time delay before opening the contactor.
For most applications, the level above which the relay senses an
overload is 115% of FLA, and the relay will hold LRA for at least
10 sec to accommodate starting of high-inertia loads.
- Motor
Starter Basics: Motor and motor branch circuit short circuit and
ground fault protection - Short circuits and ground faults
occur when conductors unintentionally contact one another, or a
grounded surface due to insulation failure, equipment damage, or
human error. Protection is provided by fuses, molded-case circuit
breakers (MCCBs), or motor circuit protectors (MCPs) installed on
the line side of the motor controller, either as part of a
combination starter or separately-mounted.
- Power
Factor Correction - Power factor is the ration between the KW
and the KVA drawn by an electrical load where the KW is the actual
load power and the KVA is the apparent load power. It is a measure
of how effectively the current is being converted into useful work
output and more particularly is a good indicator of the effect of
the load current on the efficiency of the supply system. A poor
power factor due to an inductive load can be improved by the
addition of power factor correction, but, a poor power factor due
to a distorted current waveform requires an change in equipment
design or expensive harmonic filters to gain an appreciable
improvement.
- Rules
Of Thumb
- Squirrel
cage motors - Squirrel cage motors get their name from the
appearance of early rotors. They are the most common type of
industrial AC electric motor, being rugged and requiring neither a
separate DC power source nor slip-rings. They are essentially
constant speed devices when energised by a constant frequency AC
supply, however electronic speed control is available.
- Synchronous
Motor Operation
- The
Selection, Connection, Reversing and Repair of Electric Motors
- Selecting a motor and connecting the electricals are the first
challenges encountered after purchasing that long coveted machine
tool. There are several types of single phase AC motors in current
production in the U.S., but only two types are commonly used in
powering home shop machninist equipment.
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Circuits
General information
Articles
- Answers
to FAQs on Battery Motors & Controllers
- Beakman's
Electric Motor - This article describes the worlds
simplest and cheapest 'home-made' electric motor, suitable for
demonstrations, or just plain fun.
- Battery
Motors & Controllers FAQ
- Driving
DC Motors - application note in pdf format
- Inductive
flyback catching diodes - All inductive devices, operating
in d.c. circuitry, which are switched on and off (whether by a
contact or by electronic circuitry) should have a diode
connected across their coils to catch the inductive fly back.
- Motion
Control Primer: Sizing an Industrial Motor for the Job and
selecting motor type - What kind of DC moto should be
selected for industrial application.
- Motor
Charasteristics: Measurement of Lumped Parameters -
Laporatory exercise documentation in pdf format.
- Procedure
for Identifying Permanent Magnet DC Motors - DC Motor
Overview, Permanent Magnet DC Motor Equations and Transfer
Functions, and Identification of DC Motor Parameters: Kb, Kt,
R, Jo, L, D, and Kf
- Weigh
the benefits of fuzzy-logic vs classical control in a
disk-drive spindle - you can apply fuzzy- and
classical-control techniques to any servo-control loop,
example on driving dc 3-phase, 12-pole spindle motor along
with the driver electronics
Circuits
- 12V
or 24V DC Pulse Width Modulator - This circuit can be used
as a light dimmer or DC motor speed controller.
- A
Microcontroller Based Motor Speed Control - article with
theory and circuit
- A
Microcontroller Based Motor Speed Control, Part 3 - This
article describes a two DC motor controller using 89C2051.
- Audio
amp makes efficient fan controller - with a simple
modification, you can use an audio-amplifier IC to control a
fan module
- Boost
converter controls 12V fan from 5V supply -
temperature-controlled PWM boost converter allows operation of
a 12V brushless dc fan from a 5V supply
- Circuit
generates fan-speed control - Fan noise is becoming a
significant issue as electronic equipment increasingly enters
the office and the home. Noise is proportional to fan speed.
Consider this low-cost, self-contained analog circuit for
fan-speed control. You can easily adjust the circuit for any
desired linear relationship between the fan voltage and
temperature.
- Circuit
forms dc-motor switch with brake - Controlling a small dc
motor without speed control sounds like a trivial task; a
switch or a relay should suffice. However, several problems
accompany this approach. Thic circuit can be useful for
designs that don't need precise control of speed and stopping
position but can benefit from enhanced deceleration.
- Circuits
provide 4- to 20-mA PWM control - are useful when you use
4- to 20-mA current-loop signals to control a PWM signal
- Circuit
provides bidirectional, variable-speed motor control -
During the development of systems that include small motors, a
simple, bidirectional motor controller with speed adjustment
may be helpful. This circuit is such a controller. A
transistor-based H-bridge allows two directions of rotation. A
chopper controls the upper arms of the H-bridge, thereby
enabling the speed adjustment. This circuit is designed to
work at voltages up to 15V, but can be adapted to higher
voltages.
- Computer
controller for DC motors - This circuit is easy to build
and use and it can control two DC motors of any current or
voltage rating, depending on the rating of the relays. The
circuit also provides two shaft encoders for positional
feedback to the computer.
- DC
Motor Speed Controller - Control the speed of any common
DC motor rated up to 100V (5A). Operates on 5V to 15V. Uses
NE556 to pulse-width modulate a high current switching power
transistor, TIP122. In this way motor torque is maintained.
Adjustable speed control.
- DC
Motor Controller - controls small 2.5-7V motors, in pdf
format, text in Finnish
- Digital
Speed Control for RC car - DC motor PWM controller that
takes the 1ms to 2ms pulse from the RC receiver and converts
it into a pwm train at 1Khz
- Encoder
and PC make complete motor-control system - This Design
Idea combines a simple ISA-bus-resident interface circuit; a
garden-variety PC; a high-resolution optical shaft encoder;
and a PWM-controlled, 0.05-hp, brushed, permanent-magnet dc
motor to make a high-precision and high-power motion-control
system. This circuit is designed to drive a 48W (24V, 2A)
motor. A different choice of MOSFET in the circuit would allow
the system to handle even heavier loads. The quadrature-output,
incremental optical shaft encoder that this Design Idea uses
is popular in high-performance, bidirectional,
rotation-sensing applications.
- Fan
controller adapts to system temperature
- H
Bridge Motor control - general introduction to H bridges
- H
bridge switch for small motors - simple switch circuit for
reversing and stopping a motor without any control of speed
- H-Bridge
Motor Driver - drives small DC motors up to about 100
watts or 5 amps or 40 volts
- MOSFET
switch provides efficient ac/dc conversion - suitable
circuit for DC motor powering from AC from transformer
- Motor
controller operates without tachometer feedback - used
back-EMF for motor speed controlling to make a voltage
controlled motor speed controller
- Motor-control
scheme yields four positions with two outputs - This
article shows how to position a mechanical device into four
discrete positions but with only two free outputs and one free
input from the control system. This circuit is designed for
24V-dc up to 2.5A motor that comes with a worm gear.
- Nopeudensไไdin
tuulettimelle - simle speed controller for PC fan, based
on LM317, text in Finnish
- PCB
Drill Controller - uses a Pulse-Width-Modulation technique
with current feedback to keep the speed of cheap 12V PCB
drills more constant
- PIC
Based Speed Controller - This a a controller which
controls a small DC motor to two directions at variable speed.
The control signal for this circuit are normal RC servo
control pulses.
- Position
detectors provide motor-control logic - Optical sensors
determine end of travel, and an SPDT switch selects to which
end to send the load.
- Programmable
source powers dc micromotors - a simple, economic,
compact, and tricky way of using the LM723 as a programmable
voltage source to drive dc micromotors which can can set the
output to a value of 200 mV to 6V
- Pulse
Width Modulation DC Motor Control - controls the motor
speed by driving the motor with short pulses
- PWM
Motor/Light Controller - 12 or 24V pulse width modulator
for light dimming or DC motor controlling
- PWM
Motor/Light Controller by G. Forrest Cook
- PWM
Motor/Light Controller Variations - diagrams are for 12V
operation and there are high side (common ground) and low side
(common +12V) versions
Tutorials
Technical information
- The
Stepper Motor Archive - The Stepper Motor Archive is an
online database of stepper motor data including coil winding
diagrams and electrical and mechanical data. The motivation
for such an archive is simple: There are a many surplus
stepper motors on market for which data sheets are often hard
to come by.
Stepper controllers
- First
Stepper Circuit - PIC based simple stepper controller
- Remote
two wire positioner - Send power to a remote stepper motor
and also control its rotation and speed over only two wires,
pdf file
- Rotary
controller positions stepping motor - uses a servo
potentiometer to provide the necessary drive pulses for a
stepping motor
- Stepper
Motor Controller - very simple and inexpensive circuit
built from standard components and can easily be adapted to be
controlled by a computer
- Unipolar
Stepper Motor Driver kit - Drives any 5, 6 or 8 lead
unipolar stepper motor. Based on the UCN5804 IC. All features
of this IC (direction, on/off, phase control & half step)
are brought out to SPDT PCB-mounted switches.Three run modes
supported.
Computer interface for
steppers
- A
Worked Stepping Motor Example - running stepper motors
using PC parallel port and some electronics
- Dual
Stepper Motor Controller - Connects to the PC printer port
& will drive two stepper motors up to max. 3A each. All
contained in an extended D-shell case. Will also accept 4
inputs from external switches. DOS
based software (including source) supplied to control
motors and monitor inputs. Software will run interactively or
process a text file of commands. Software even allows manual
single stepping of motors.
- PC's
BIOS interrupt drives twin stepper motors - design idea
for computer controlled stepper motor system
- Slot
machine sheet stepper motor controls - Stepper motor
driver stage for two stepper motors using two L297 driver ICs.
This circuit take control bits from computer parallel port or
other I/O port with TTL signals.
- Software
for Stepper Motor Control - Simple stepper motor
controlling software examples using C, C++, Turbo Pascal,
Basic and MswLogo programming languages. This page has also
link the the simple motor driver hardware suitable for the
software.
- Stepper
Motor Control program Step - Step is a little utility that
allows you to drive up to two 4-phase unipolar stepper motors
connected to the parallel port. It can do absolute (to a
certain angular position) or relative (clockwise or counter-
clockwise by a certain angle) movement at every speed. Angles
may be measured in steps, degrees or revolutions, and
movements can be in wave, two-phase, or half-step mode. This
program is made for POSIX / Linux systems. The program
documentation includes also the driver hardware circuit
diagram and circuit board design.
- Stepper
motors - how to connect to pc and useful link collection
- Tonytronic
Soft Robot - circuit and software for controlling 16
steppermotors
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