Output characteristics

Eig. 11. (a) Common emitter circuit and (b) output characteristics for the n—p—n transistor, where is the operating (quiescent) point as determined by Rg. 

Figure 24.9 shows a typical output characteristic or reactive capability curve of a generator, illustrating the stability levels of the machine under different conditions of operation. The machine must operate within these levels and the voltage profile within the specified voltage limits, as noted in Table 24.3. 

The control-to-output characteristic curves for a current-mode controlled flyback-mode converter, even though it is operating in variable frequency, are of a single-pole nature. So a single pole-zero method of compensation should be used. The placement of the filter pole, ESR zero, and dc gain are... 

The form of compensation is the 2-pole-2-zero method of compensation. This is to compensate for the effect of the double pole caused by the output filter inductor and capacitor. One starts by determining the control-to-output characteristic of the open-loop system. 

B.2 Defining the Open Loop Response of the Switching Power Supply—The Control-to-Output Characteristics... 

This causes the control-to-output characteristic to add gain and phase above the location of this zero. This can be a problem with respect to the stability of the supply. Unfortunately, many capacitor manufacturers do not present the value of the ESR for their capacitors. Typically, the zero caused by the output filter capacitor falls in the following range ... 

As one can see, the choice of the type of output filter capacitor can influence the control-to-output characteristic, sometimes detrimentally. 

The operation of a discontinuous-mode, flyback converter is quite different from that of a forward-mode converter, and likewise their control-to-output characteristics are very different. The topologies that fall into this category of control-to-output characteristics are the boost, buck/boost, and the flyback. The forward and flyback-mode converters operating under current-mode control also fall into this category. Only their dc value is determined differently. Their representative circuit diagram is given in Figure B-12. 

The zero attributed to the output filter capacitor is still present in the control-to-output characteristics. Its location is found in Section B.2.1 and Equation B.9. 

The resulting control-to-output characteristics are shown in Figure B-13. As one can see, both the input voltage and the equivalent load resistance have an influence on the gain and phase functions. 

The current-mode controlled forward converter has one additional consideration there is a double pole at one-half the operating switching frequency. The compensation bandwidth normally does not go this high, but it may cause problems if the closed-loop gain is not sufficiently low enough to attenuate its effects. Its influence on the control-to-output characteristic can be seen in Figure B-14. 

Figure B-13 The control-to-output characteristics for a voltage-mode controlled flyback converter.

The schematic and Bode plot for the single-pole method of compensation are given in Figure B-16. At dc it exhibits the full open-loop gain of the op amp, and its gain drops at -20dB/decade from dc. It also has a constant -270 degree phase shift. Any phase shift contributed by the control-to-output characteristic... 

The commercial units have a very low thermal capacity and very high response speeds. Some are available with several independent channels and a common cold junction. Each channel is scanned in turn by the instrument, and the readings either displayed or stored for future recovery. Accuracies of better than 0.2 per cent are possible. Thermocouples are available to cover a very wide range of temperatures, their cost is low and they have a small mass, so minimizing the intrusive effect on the surface at the point where the temperature is being measured. The output characteristics (output voltage versus temperature) are reasonably linear but the measurement accuracy is not particularly high. 

For low-temperature heating systems using natural convective or radiant appliances the normal design water flow temperature to the system is 83°C (see also Table 27.8). Boost temperatures may be used on modulated-temperature systems because of the changes in heat output characteristics with varying temperatures. Additionally, comfort aspects must be borne in mind, as forced convective emitters operating on modulated temperature systems can deliver air streams at unacceptably low temperatures. 

A comparison of typical properties of cathodic protection materials is given in Table 10.23, but is by no means comprehensive. It is obvious that the modification of an alloy, environment or other important factors will be reflected in the life and output characteristics. In some cases the maximum voltages and current densities recommended can be vastly exceeded. In others, particularly where abnormal levels of environmental dissolved solids are met, factors of safety should be applied to modify the proposed figures. Acceptance of a much reduced or uncertain life, weighed against a possible economy, may also influence the chosen working limits. For example, the life of ferrous alloy anodes may, in practice, be only two-thirds of that expected because of preferential attack eventually leading to disconnection of all or part of the anode from the source of e.m.f. 

Output Characteristics. The characteristics of an expl component which determine the form and magnitude of the energy released. See under Output Tests in Vol 4, D1084ff... 

Output Characteristics for a p-n-p Transistor in Common-Emitter Mode... 

The OPMBS used a custom-written spreadsheet application, i.e., a workbook, in conjunction with laboratory automation systems to standardize data recording, calculations, and presentation of results. Devising this approach required careful differentiation between (a) the workbook used to calculate and report the results and (b) the data acquisition systems used in each laboratory. The laboratory systems were used to collect the raw chromatographic data, but the calculation modules in the laboratory systems were not used. Instead, all calculations were done in the workbook. Use of the laboratory systems to collate and output the final results was considered but was rejected for two reasons. First, different laboratories used different systems, and some laboratories used more than one system. The output characteristics of the various systems differed considerably and would have required extensive modification... 

On-line SFE-SFC modes present several distinct advantages that are beyond reach of either technique when used separately (Table 7.13). An obvious advantage of SFE is that it is an ideal way to introduce a sample into an SFC system. Because the injection-solvent is the same as the mobile phase, in this respect the criteria for a successful coupling of different techniques are fulfilled [94], i.e. the output characteristics from the first instrument and the input characteristics of the second instrument are compatible. Supercritical fluid techniques can separate high-MW compounds are significantly faster than classical Soxhlet extractions and require less heat and solvent. SFE-SFC techniques are versatile,... 

Figure 12 shows the input to output, characteristic waveform for a two position controller that switches from its "OFF" state to its "ON" state when the measured variable increases above the setpoint. Conversely, it switches from its "ON" state to its "OFF" state when the measured variable decreases below the setpoint. This device provides an output determined by whether the error signal is above or below the setpoint. The magnitude of the error signal is above or below the setpoint. The magnitude of the error signal past that point is of no concern to the controller. 

The combination of the two control modes is called the proportional plus reset (PI) control mode. It combines the immediate output characteristics of a proportional control mode with the zero residual offset characteristics of the integral mode. 

Figure L Cell (lower left), cell energetics at maximum power point (upper left), and output characteristics (right) for an n-type WS2-based photoelectrochemical cell, The electrolyte is 12 M LiBr and Eredox = +0,64 V vs, SCE for current density multiply current shown times 32 cm 2...

Figure 5. Output characteristics and photocurrent density at maximum power point against time (inset) for an intrinsic a-Si H photoanode-based cell. (Reproduced from Ref. 5.)...

Figure 5.7. The output characteristics of the TFT formed using a spin-coated silicon film and whose transfer properties are shown in Figure 5.6. [Reproduced with permission from Ref. 10. Copyright 2006 Nature Publishing Group.]...

TABLE 6.5. AMO Output Characteristics of Solar Cells Fabricated With AACVD-Deposited CuInS2 Films... 

Figure 10.13. (a) SEM image of ZnO nanorods coated with octylamine. Scale bar, 200 nm. (b) Uniform nanorod film fabricated by spin coating of ZnO nanorods. Scale bar, 500 nm. The nanorods assemble into domains with nematic ordering, (c) Saturated transfer characteristics for a thin-film transistor fabricated by spin coating of ZnO nanorods with different ligands octylamine (solid line), butylamine (dashed line). Vi = 60V. (d) Output characteristics of a spin-coated device made from octylamine-stabilized ZnO nanorods.The device structure is shown in the inset in (c). Reproduced from Ref. 83, Copyright 2006, with permission from the American Chemical Society. 

Fig. 2.1 Basic microring resonator structures and their output characteristics, (a) One ring resona tor and one bus waveguide and (b) the corresponding resonance spectrum at the through port, (c) One ring resonator and two bus waveguides and (d) the corresponding resonance spectrum at the through port and drop port. Reprinted from Ref. 15 with permission. 2008 Institute of Electrical and Electronics Engineers...

Dyeing applications, tetrahydrofurfuryl alcohol in, 12 279 Dyeing theory, 26 394-395 Dyeing transition temperature, 9 159 Dye intermediates, 9 265-298 chemistry, 9 266-291 classification, 9 265-266 economic aspects, 9 293-295 equipment and manufacture, 9 291-293 health and safety factors, 9 295-298 obtained by nitration, 9 2 7 It obtained by sulfonation, 23 525 unit processes, 9 269-283 Dye lasers, 74 702-705 23 144 output characteristics of, 74 705 Dye-ligand affinity chromatography, 6 402 Dye liquor, 9 163 Dye manufacturing... 

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