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Transformers and Alternating Current
Transformers and Alternating Current

... Irregular Ideally what comes out of a wall socket is sinewave. Square or sawtooth waves may be produced by some low-end uninterruptible power supplies when operating from the battery. Some AC waveforms are irregular, particularly those carrying information AC waves are produced by audio amplifiers ...
Motor start-up
Motor start-up

... Autotransformer start-up This method is often used for starting up large motor loads. The autotransformer has a main winding designed for the rated voltage with a terminal which is connected to the motor. Noratel supplies both single and threephase transformers. The combination of large electric mot ...
catelog and detailed specifications
catelog and detailed specifications

... Our 4kVA SRNDTI Series UPS & UPR’s are Power Factor Corrected (PFC) on the input to near unity. Therefore, when non-linear loads requiring apparent power are present, only real power is reflected on the input utility line, ensuring efficient use of electricity and preventing harmful load harmonics f ...
LDD-1 AC-3/RF Demodulator User Guide
LDD-1 AC-3/RF Demodulator User Guide

BPL - uidaho.edu
BPL - uidaho.edu

... Modulation schemes (such as Orthogonal Frequency Division Multiplexing - OFDM) have been developed for these very complex channels. These schemes spread the signal among numerous carriers over a wide bandwidth. They are designed so that carriers can either be “turned off” or not available due to att ...
Atmel LED Driver-MSL3162 Datasheet Brief Power Control and 1MHz I
Atmel LED Driver-MSL3162 Datasheet Brief Power Control and 1MHz I

... The MSL3162 drives 16 strings of series-connected LEDs. The maximum number of LEDs per string is limited to 10 white LEDs by the 40V maximum string voltage rating. More series LEDs can be driven if their forward voltage (VF) is lower. When an LED string is turned off, the voltage across the LEDs doe ...
Analog-to-Digital Conversion
Analog-to-Digital Conversion

Load Flow Study using Tellegen`s Theorem
Load Flow Study using Tellegen`s Theorem

Graphic Equalizer Design
Graphic Equalizer Design

... experimentation the gain at the lower frequencies/bands was more than 6 dB higher than that for the bands 6 th and 7th, this problem was encountered as well during simulation and it was fixed by decreasing the resistors in the simulated inductor op amp feedback network so that the voltage attenuatio ...
L6374
L6374

... switching when the inductor can discharge; while the switching looks "delayed" if the output transition tends to initiate a charging phase (see Figure 9). With a load almost free from parasitic elements, the waveforms resemble the ones of the purely resistive cases. With a real, more composite load, ...
Audio amplifier for portable applications NXP 3-W Class AB, BTL audio amplifier SA58631
Audio amplifier for portable applications NXP 3-W Class AB, BTL audio amplifier SA58631

... The NXP 3-W Class AB, BTL audio amplifier SA58631 increases increases dissipation capability, so it is an excellent choice for a broad range of portable applications, including mobile radios, 9- and 12-V speakers, toys, games, and PC sound cards. It also supports operating systems that run between 2 ...
Technical Article
Technical Article

... the feedback loop is a fundamental component of the converter system, so it cannot be turned off completely. The trick, then, is to design the converter in such a way that internal blocks can be shut down when not needed, but turned on and made ready extremely fast when required. In fact, this mode ...
Typical Conson Specification
Typical Conson Specification

... Provide override switches as detailed on the drawings, which shall incorporate the following: Switches shall function so as to operate the local controllers in case of a bus failure to other areas under control. There shall be the facility to switch directly onto local modules or via the bus from re ...
DATASHEET SEARCH SITE | WWW.ALLDATASHEET.COM
DATASHEET SEARCH SITE | WWW.ALLDATASHEET.COM

... frequency shaping the feedback path. This is done with a series RC from pin 1 to 5 (paralleling the internal 15 kΩ resistor). For 6 dB effective bass boost: R=15 kΩ, the lowest value for good stable operation is R=10 kΩ, if pin 8 is open, If pins 1 and 8 are bypassed then R as low as 2 kΩ can be use ...
Department of Electrical and Computer Engineering Power Systems Name:__________________________________
Department of Electrical and Computer Engineering Power Systems Name:__________________________________

... d) In the power system shown in Fig. 4, two 30 kV generators are connected to a 400 kV transmission line through a 30/400 kV transformer. Impedances of the generators and the transformer are given in pu based on their own ratings. Find the fault level (short circuit ...
lab proceedures (word format) - Rose
lab proceedures (word format) - Rose

Disconnect Switches
Disconnect Switches

... available fault current. • Distribution lines connected to substations that have several transmission lines or are near a generation plant might have extremely high short-circuit fault current available if something were to happen out on the distribution line. • By inserting a series reactor on each ...
stepper motor
stepper motor

... width of the pulse,the pulse duration, based on modulator signal information. 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. ...
Follow this link to Class 6 Spring 2003
Follow this link to Class 6 Spring 2003

... synchronization. Thus the design of AMI requires that a certain ONES DENSITY be maintained, that a certain minimum of the bits over a certain period of time be guaranteed to be a ONE (pulse). This is why AMI circuits require DENSITY enforcement ...
Current in a transformer
Current in a transformer

FAN8060 1.2 MHz, 1 A Synchronous Step-Down DC/DC Regulator F
FAN8060 1.2 MHz, 1 A Synchronous Step-Down DC/DC Regulator F

... FAN8060 employs cycle-by-cycle current limiting, which limits current by reducing duty cycle during overload. As the load increases beyond the limit, the output voltage starts to reduce, thereby reducing the FB voltage. When the FB node is half the reference voltage and the COMP node has reached max ...


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english - KEK Concept GmbH
english - KEK Concept GmbH

... Class-leading low voltage drive contributes to greater energy efficiency and performance in compact battery-driven industrial equipment Willich-Münchheide, August 25, 2016 LAPIS Semiconductor, a member of the ROHM group, has announced the development of the ML620130 family of 16bit low power MCUs, o ...
Multilevel Power Converter Based on a Three Single
Multilevel Power Converter Based on a Three Single

... multilevel inverters, in medium and high-power applications features like safety and robustness are also important. For this purpose isolated systems in low frequency are used, being multilevel converters associated with line-frequency power transformers proposed. Three single-phase or one three-pha ...
Motor Basic – Key terms for motor control
Motor Basic – Key terms for motor control

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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.
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