Resistor, nonlinear

Temperature detectors embedded in the motor winding give close, accurate indication of motor temperature. Both conventional resistance temperature detec tors (RTD) and special thermistors (highly temperature-sensitive nonlinear resistors) are used. With appropriate auxiliaries these devices can indicate or record motor temperature, alarm, and/or shut down the motor. 

It was observed that with a linear circuit and in the absence of any source of energy (except probably the residual charges in condensers) the circuit becomes self-excited and builds up the voltage indefinitely until the insulation is punctured, which is in accordance with (6-138). In the second experiment these physicists inserted a nonlinear resistor in series with the circuit and obtained a stable oscillation with fixed amplitude and phase, as follows from the analysis of the differential equation (6-127). 

Barium titanate (BaTiOj), a perovskite-type electro-ceramic material, has been extensively studied and utilized due to its dielectric and ferroelectric properties. The wide applications of barium titanates include multiplayer capacitors in electronic circuits, nonlinear resistors, thermal switches, passive memory storage devices, and transducers. In addition, barium titanate can be used for chemical sensors due to its surface sensivity to gas adsorption. 

A nonlinear resistor) Suppose the resistor in Example 2.2,2 is replaced by a nonlinear resistor. In other words, this resistor does not have a linear... 

If a semiconductor element with negative differential conductance is operated in a reactive circuit, oscillatory instabilities may be induced by these reactive components, even if the relaxation time of the semiconductor is much smaller than that of the external circuit so that the semiconductor can be described by its stationary I U) characteristic and simply acts as a nonlinear resistor. Self-sustained semiconductor oscillations, where the semiconductor itself introduces an internal unstable temporal degree of freedom, must be distinguished from those circuit-induced oscillations. The self-sustained oscillations under time-independent external bias will be discussed in the following. Examples for internal degrees of freedom are the charge carrier density, or the electron temperature, or a junction capacitance within the device. Eq.(5.3) is then supplemented by a dynamic equation for this internal variable. It should be noted that the same class of models is also applicable to describe neural dynamics in the framework of the Hodgkin-Huxley equations [16]. 

Thus, the memristor can be treated as a nonlinear resistor. The nonlinearity lies in the fact that the memristance is a function both of time and an internal state variable x, that is M(x,t). This state variable is often (but not always) proportional to the electric charge Q. 

Equation 9.7 might be represented by means of a C element in derivative causality and a nonlinear resistor (Fig. 9.2). 

Nonlinear resistors, which have been specially designed to depend strongly on a parameter such... 

Nonlinear resistors have a resistance that depends strongly on some external parameter. For any resistor the resistance depends on many parameters, but nonlinear resistors are specially made to show such a dependence. Usually the parameters are voltage or temperature. The major kinds are... 

Nonlinear resistors consist of a piece of ceramic material with two metal connections at opposing sides. Usually the device is insulated with some kind of organic coating. The shape and dimensions may vary widely depending on type, manufacturer, and specification. Within each kind of nonlinear resistor special types are available for many specific applications. 

There is a growing demand for SMD types of nonlinear resistors. 

Nonlinear resistor A resistor with a value that depends strongly on some external parameter such as temperature (thermistor) or voltage (varistor). 

Another type of nonlinear resistor is the ordinary tungsten incandescent light bulb, with a characteristic curve as shown at the right-hand side of the figure. The resistance is very low when the wire is cold, but it rises as current heats the wire more, because there is more "scattering" of the electrons. 

Silicon carbide is manufactured in many complex bonded shapes, which are utilized for super-refractory purposes such as setter tile and kiln furniture, muffles, retorts and condensers, skid rails, hot cyclone liners, rocket nozzles and combustion chambers, and mechanical shaft seals. It is also used for erosion- and corrosion-resistant uses, such as check valves, orifices, slag blocks, aluminum die-casting machine parts and sludge burner orifices. Electrical uses of SiC include lightning arrestors, heating elements and nonlinear resistors. 

The base-emitter characteristic can be expressed by a nonlinear resistor model installed in the EMTP. Although both TYPE-92 and TYPE-99 models accept point-by-point data expressing its current-voltage characteristic, only the true nonlinear resistor model (TYPE-92) is suitable for the simulation from the viewpoint of stability. This characteristic is easily obtained from the data sheet of the transistor. 

The nonlinear characteristic between the base and emitter of the transistor is expressed by a nonlinear resistor R eq- This characteristic can be expressed by a TYPE-92 ZnO arrester model installed in the EMTP (Lines 42-58). The current-voltage characteristic is almost identical to that of a diode, and is given by point-by-point data. 

The nonlinear characteristic between the collector and emitter cannot be expressed by any conventional nonlinear resistor model, such as the TYPE-92 resistor, because its characteristic depends not only on its terminal voltage Vce but also on the base current Jg. The resistor is expressed by the TYPE-91 TACS-controlled resistor. Its resistance is calculated in the TAGS according to the collector-emitter voltage CE> base current and transient characteristic of a transistor. This modeling technique is explained in Section 4.2.3. 

List 4.9 and Figure 4.20 show input data for the switching circuit using the nonlinear resistor model. In these data, the dynamic on-resistance (Equation 4.23) and the saturation characteristic (Equation 4.24) are neglected because they might have minor effects on the result. The data also include a thermal model, described in Section 4.2.4. 

The train operation is modeled by the current sources and nonlinear resistors illustrated in Figure 4.25. Train position is obtained from train velocity v(t) using an integrator (1/s) illustrated in Figure 4.26 ... 

The nonlinear characteristic between the base and emitter of fhe transistor is expressed by a nonlinear resistor This characteristic can be expressed... 

The movement of a train is modeled by current sources 4(f) with the aforementioned nonlinear resistors. A current source in the section, where the train is running, is activated, and the other sources are inactivated ... 

---