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unit-2: dc motor
unit-2: dc motor

... 1. Explain Swinburne’s test for finding the efficiency of a D.C. machine. Can this method Applicable to d.c. series motors. 2. Describe Hopkinson’s test in detail with its advantages disadvantages. 3. How the efficiency of each machine on full load is obtained from the regenerative test ? ...
eautioll Warllillg - technicalaudio.com
eautioll Warllillg - technicalaudio.com

... Having set up the PTA 3 , amplifier with the basic recorder unit as indicated above, a number of steps should be followed. 1. To make a recording, a suitable input must be connected to the recording amplifier. This may be done by use of anyone, or all, of the bridging or microphone inputs. The micro ...
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... ground-reference point. Some examples of floating signal sources are outputs of transformers, thermocouples, battery-powered devices, optical isolators, and isolation amplifiers. An instrument or device that has an isolated output is a floating signal source. Refer to Field Wiring and Noise Consider ...
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Photodiode Technical Information
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... region at the junction between the P- and N-layers is known as the depletion layer. By controlling the thickness of the outer P-layer, substrate N-layer and bottom N+layer as well as the doping concentration, the spectral response and frequency response can be controlled. When light strikes a photod ...
AN092 -- Measuring Bluetooth Low Energy
AN092 -- Measuring Bluetooth Low Energy

... You will also need to have a central device in order to form a connection with the Keyfob. The simplest way to do this is to use the USB Dongle in the CC2540DK-MINI kit running the standard HostTestRelease application, with BTool used to control the dongle. With dongle connected to the PC and the Ke ...
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Principles of Electronic Communication Systems

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2.0 EMC Requirements Analysis

... may require additional EMC performance requirements, which will necessitate additional verification testing of the product. I certify that the product samples submitted for EMC testing are of a production representative design. I agree to submit a summary report directly to the JLR EMC department no ...
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... MOSFETs and Schottky diode in synchronous DC:DC power supplies that provide various peripheral voltages for notebook computers and other battery powered electronic devices. FDS6994S contains two unique 30V, N-channel, logic level, PowerTrench MOSFETs designed to maximize power conversion efficiency. ...
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... Since the power capacity per generating unit is relative low but the cost of energy is relative high, there are always strong demands for high efficiency in order to reduce the cost of PV energy. In respect to efficiency, the power electronics system (including passive components) counts for the mos ...
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... synchronous machines, the interconnection customer may inform the ISO that it elects to comply with the revised requirement. The reactive power sources needed to comply with this design requirement can be provided by: (1) the inverters associated with the asynchronous generation, (2) switched or fix ...
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... With its high variety of I/O interfaces, small form factor, low power dissipation, and standard MIL-STD-1553B avionics bus interface (RT), the A175 handily meets these requirements. It can be used to expand the I/O capabilities of any avionics computer with a standard MIL-STD-1553B interface. For se ...
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... complete power-supply system. The main DC-DC converter is a high-frequency (500kHz/1MHz), current-mode step-up regulator with an integrated N-channel power MOSFET that allows the use of ultra-small inductors and ceramic capacitors. With its high closed-loop bandwidth performance, the MAX1889 provide ...
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2.0 EMC Requirements Analysis

... may require additional EMC performance requirements, which will necessitate additional verification testing of the product. I certify that the product samples submitted for EMC testing are of a production representative design. I agree to submit a summary report directly to the JLR EMC department no ...
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... [email protected], [email protected] , [3][email protected] Abstract- Comparator is one of the basic building blocks of analog to digital converter. The need for ultra-low-power, area efficient and high speed analog-to-digital converters is pushing toward the use of dynamic regenerat ...
Asynchronous generator
Asynchronous generator

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Novel Three-Phase CM/DM Conducted Emission Separator

... DM emissions. Other methods that apply mathematical analysis through fast Fourier transformation [14] have also been proposed. There, it is important that sampling rates are high enough and phase information is computed correctly, which usually leads to expensive or inaccurate measurements. A three- ...
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Presentazione di PowerPoint

Fault Analysis on Distribution Feeders With Distributed Generators
Fault Analysis on Distribution Feeders With Distributed Generators

... output of the IIDG, the controller adjusts the amplitude and the phase of this synthesized inverter voltage ( ) with respect to its terminal voltage ( ). Therefore, the voltage controlled equivalent circuit, shown in Fig. 2(a), can be used to represent the IIDG during the transient period for this c ...
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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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