• Study Resource
  • Explore
    • Arts & Humanities
    • Business
    • Engineering & Technology
    • Foreign Language
    • History
    • Math
    • Science
    • Social Science

    Top subcategories

    • Advanced Math
    • Algebra
    • Basic Math
    • Calculus
    • Geometry
    • Linear Algebra
    • Pre-Algebra
    • Pre-Calculus
    • Statistics And Probability
    • Trigonometry
    • other →

    Top subcategories

    • Astronomy
    • Astrophysics
    • Biology
    • Chemistry
    • Earth Science
    • Environmental Science
    • Health Science
    • Physics
    • other →

    Top subcategories

    • Anthropology
    • Law
    • Political Science
    • Psychology
    • Sociology
    • other →

    Top subcategories

    • Accounting
    • Economics
    • Finance
    • Management
    • other →

    Top subcategories

    • Aerospace Engineering
    • Bioengineering
    • Chemical Engineering
    • Civil Engineering
    • Computer Science
    • Electrical Engineering
    • Industrial Engineering
    • Mechanical Engineering
    • Web Design
    • other →

    Top subcategories

    • Architecture
    • Communications
    • English
    • Gender Studies
    • Music
    • Performing Arts
    • Philosophy
    • Religious Studies
    • Writing
    • other →

    Top subcategories

    • Ancient History
    • European History
    • US History
    • World History
    • other →

    Top subcategories

    • Croatian
    • Czech
    • Finnish
    • Greek
    • Hindi
    • Japanese
    • Korean
    • Persian
    • Swedish
    • Turkish
    • other →
 
Profile Documents Logout
Upload
3-Terminal Positive Regulators
3-Terminal Positive Regulators

Power Semiconductor Devices
Power Semiconductor Devices

... Turn on and off require a small pulse ...
Regulated Power Supply.doc
Regulated Power Supply.doc

... regulation, eliminating the distribution problems associated with single point regulation. The voltages available allow these regulators to be used in logic systems, instrumentation, HiFi, and other solid state electronic equipment. Although designed primarily as fixed voltage regulators these devi ...
Energy Control and Observation System Energy Control and
Energy Control and Observation System Energy Control and

English  - Circuit Test Electronics
English - Circuit Test Electronics

MSU_Ginn_MVDC
MSU_Ginn_MVDC

... • VSCs can operate in voltage regulation mode or in power dispatch mode. • Optimal settings of converters ensure desired power management and also avoid excessive voltage build up under failure of one of the converters. ...
Stepper Motors - WordPress.com
Stepper Motors - WordPress.com

...  big forces without gears  actuators are simple  in mobile machines ...
UCI Power Electronics Lab
UCI Power Electronics Lab

Model WP1P Pulse Repeater
Model WP1P Pulse Repeater

... <> <> ...
Introduction to the Oscilloscope
Introduction to the Oscilloscope

... worth 5 seconds, what time is represented by this point? ...
KB ELECTRONICS, INC. 12095 NW 39th Street, Coral Springs
KB ELECTRONICS, INC. 12095 NW 39th Street, Coral Springs

... used, the shield must be securely grounded at the AC and DC Drive end only. However, there may be times when grounding the shield is not necessary. This may only be determined by trial and error. ...
NTE6410 Unijunction Transistor UJT
NTE6410 Unijunction Transistor UJT

... Note 3. Intrinsic standoff ratio, is defined in terms of peak–point voltage, VP, by means of the equation: VP = η VB2B1 VF, where VF is approximately 0.49 volts at +25°C @ IF = 10µA and decreases with temperature at approximately 2.5mV/°C. Components R1, C1, and the UJT form a relaxation oscillator, ...
U26130135
U26130135

ON DELAY | INLINE (SERIES CONNECTION)
ON DELAY | INLINE (SERIES CONNECTION)

... to select any time delay. The THL-8 Series is a compact 2” x 2” encapsulated enclosure with a universal input voltage. It is connected in series with the load requiring only 2 terminals/connections. ...
Unit 4i - WordPress.com
Unit 4i - WordPress.com

... These are sometimes known as continuous wave modulation methods to distinguish them from pulse code modulation (PCM), which is used to encode both digital and analog information in a binary way. Radio and television broadcast stations typically use AM or FM. Most two-way radios use FM, although some ...
Design Overview of Luminious Audio Technology
Design Overview of Luminious Audio Technology

... The input gain stage utilizes cascoded/paralleled JFET topology for extremely low noise and outstanding low-level resolving capabilities. ...
Microwave Oscillators
Microwave Oscillators

... The stable reference source is usually a crystal controlled oscillator, Can be be housed in a temperature controlled environment for even greater stability. Eliminates the need for many independent crystal oscillators in a multichannl system (ex. GSM system) Can be easily implemented using a variety ...
PDF
PDF

... its duty cycle. It’s very important to select the proper dc-dc converter which plays vital role for maximum power point tracking operation. There are many factors such as cost, efficiency, flexibility and energy flow which are considered for selection of proper PV converter. The SEPIC, conventional ...
The Circuit The circuit of the Wobbulator W11 appears in Fig. 2
The Circuit The circuit of the Wobbulator W11 appears in Fig. 2

From washing machine motor to micro hydro generator
From washing machine motor to micro hydro generator

... Michael Lawley found one of these washing machines on a rubbish dump a few years ago and took it home. He found that the unique characteristics of its motor made it ideal for generating electricity over the wide range of conditions that can be expected in the micro hydro and small windpower field. H ...
Test - Yu Chun Keung Memorial College No. 2
Test - Yu Chun Keung Memorial College No. 2

... (c) Returning to the initial conditions of operation of the circuit prior to (a) and considering that the long solenoid acts purely as an inductance (i.e., of negligible resistance), determine the effect on the waveform of reducing the frequency by half, if the source voltage is kept constant . Draw ...
Detailed Specifications
Detailed Specifications

PowerGUARD
PowerGUARD

EE595_Team4_P2_Fall07
EE595_Team4_P2_Fall07

Tap 416-5: Transformers - Teaching Advanced Physics
Tap 416-5: Transformers - Teaching Advanced Physics

... would you expect between VpIp and VsIs? What would this predict for the ratio Ip/Is? Comment on how closely your values match these ‘ideal’ predictions, and explain any discrepancies. ...
< 1 ... 1101 1102 1103 1104 1105 1106 1107 1108 1109 ... 1202 >

Pulse-width modulation



Pulse-width modulation (PWM), or pulse-duration modulation (PDM), is a modulation technique used to encode a message into a pulsing signal. Although this modulation technique can be used to encode information for transmission, its main use is to allow the control of the power supplied to electrical devices, especially to inertial loads such as motors. In addition, PWM is one of the two principal algorithms used in photovoltaic solar battery chargers, the other being MPPT.The average value of voltage (and current) fed to the load is controlled by turning the switch between supply and load on and off at a fast rate. The longer the switch is on compared to the off periods, the higher the total power supplied to the load.The PWM switching frequency has to be much higher than what would affect the load (the device that uses the power), which is to say that the resultant waveform perceived by the load must be as smooth as possible. Typically switching has to be done several times a minute in an electric stove, 120 Hz in a lamp dimmer, from few kilohertz (kHz) to tens of kHz for a motor drive and well into the tens or hundreds of kHz in audio amplifiers and computer power supplies.The term duty cycle describes the proportion of 'on' time to the regular interval or 'period' of time; a low duty cycle corresponds to low power, because the power is off for most of the time. Duty cycle is expressed in percent, 100% being fully on.The main advantage of PWM is that power loss in the switching devices is very low. When a switch is off there is practically no current, and when it is on and power is being transferred to the load, there is almost no voltage drop across the switch. Power loss, being the product of voltage and current, is thus in both cases close to zero. PWM also works well with digital controls, which, because of their on/off nature, can easily set the needed duty cycle.PWM has also been used in certain communication systems where its duty cycle has been used to convey information over a communications channel.
  • studyres.com © 2025
  • DMCA
  • Privacy
  • Terms
  • Report