Showing papers on "Electrical network published in 1982"

Energy coupling between regions 1 and 2 Birkeland current systems

Abstract: The principle of ring current shieldding and the concept that in an electrical circuit analogy the ring current can be treated as a pseudo-Hall current flowing in parallel with the ionospheric Hall current are used here to develop a simple model for the electrical coupling between the applied potential Φ associated with the Region 1 currents, and the ring current, associated with the Region 2 currents. The approach yields a formula for the radial position of the inner edge of the ring current as a function of Φ, which agrees with similar formulas derived previously on the basis of different approaches. The model can be expressed in the language of electrical circuit theory as an applied potential Φ driving a nonlinear RL circuit, in which the resistance R results from dissipation in the ionosphere and the inductance L from the energy of compression stored in the ring current. The formulation lends itself to a determination of the relative amounts of energy that are dissipated in the ionosphere and stored in the ring current, according to the applied potential model. If the shielding time scale L/R and the energization (i.e., substorm) time scale are comparable, as observations indicate, roughly equal amounts of energy are expended on both elements. The analysis shows that AE type geomagnetic indexes and the Dst index should bear different functional relationships to that combination of solar wind parameters that is primarily responsible for geomagnetic activity.

Interfacial blister bonding for microinterconnections

Abstract: A method for producing microinterconnections including the steps of providing a first support member bearing electrical circuit elements including first electrical contacts and first electrical traces, providing a second support member bearing electrical circuit elements including second electrical contacts and second electrical traces, placing the second support member in face-to-face spaced and aligned relationship with respect to the first support member, and applying energy to the first support member for moving portions thereof underlying ones of the first contacts toward and into intimacy with aligned ones of the second contacts.

Symmetrical Components, As Applied to the Analysis of Unbalanced Electrical Circuits

Abstract: IT was in 1918 that Prof. C. L. Forteseue published his now classic paper on “The Method of Symmetrical Coordinates Applied to the Solution of Polyphase Networks”, A considerable literature dealing with the solution of unbalanced polyphase circuits by his method has resulted; and indeed the present authors claim that it is the only practicable method of solving unbalanced electric circuits. The method has also been applied to all manner of problems in power distribution, particularly to the investigation of unsymmetrical transient disturbances. The present volume claims to be the first which gathers together the fundamental theory on which the method is based and discusses the principal applications.Symmetrical Components: as Applied to the Analysis of Unbalanced Electrical Circuits.By C. F. Wagner R. D. Evans. Pp. xvi + 437. (New York: McGraw-Hill Book Co., Inc.; London: McGraw-Hill Publishing Co., Ltd., 1933.) 30s. net.

Network Analysis Approach to Multidimensional Modeling of Transistors Including Thermal Effects

Abstract: A comprehensive numerical model for simulating the electrical and thermal behavior of a bipolar transistor is developed. The proposed model is in the form of an electrical network for its easy implementation using a circuit analysis program. One of the suggested solution techniques enables us to simulate a fairly large problem with a reasonable amount of computer time. The effect of temperature dependence of thermal conductivity of the device material upon thermal instability is shown. It is described how the model can be used to find the appropriate values of ballasting resistors desired for the improvement of thermal stability. Prediction of a safe operating area using the proposed model is also reported.

The calculation of temperature distribution in punch-through structures during pulsed operation using the transmission line modelling (TLM) method

Abstract: Finite difference methods are frequently used to model heat flow in semiconductors. However space and time discretisation of the heat equation introduces errors. The transmission line modelling technique (TLM) is a useful alternative in that it solves an equivalent electrical network exactly. The extent of error depends only on how well an equivalent electrical network matches a physical problem. The TLM method has been used to model the behaviour of punch-through diodes during pulsed operation. The results indicate that the mechanism of heat dissipation within the active region of this type of device will have to be described more accurately if agreement between theory and experiment is to be obtained.

Method for displaying physical measurement quantities on an analogue scale and electrical circuit arrangement for carrying out the method

Abstract: To be able to combine the advantages of an analogue display with the advantages of a digital display in an electrical measuring and control unit, a method for displaying physical measurement quantities which can be converted into electrical quantities or are electrical quantities themselves on an analogue scale is proposed in which the measurement quantities are displayed directly as digital electrical quantities or indirectly after conversion of analogue into digital electrical quantities on a liquid crystal display (LCD) constructed as a scale and the upper and lower scale limit value is set in such a manner that the setpoint of the measurement quantity to be displayed appears at a predeterminable point on the scale, particularly at the centre of the scale.

Network Analogs of Maxwell's Field Equations in One and Two Dimensions

Abstract: Network analogs are developed representing Maxwell's equations in the time domain for one and two spatial dimensions. Maxwell's equations are first cast into matrix form. Then the connection between these matrices and the branch node incidence matrix of the equivalent network is made. Next, the relationship between the field variables (electric and magnetic fields) and the across and through variables (currents and voltages) of the network is demonstrated, resulting in Ohm's law for electromagnetic fields in the time domain. Although not required for the derivation, the connected graphs (electrical circuits) of the network analogs are shown. Finally, the appropriate network analog is applied to the practical problem of determining the transient response of a dipole antenna to an incident electromagnetic field.

Electrical circuit and method of controlling such

Abstract: An electrical circuit for an automotive type air conditioning system. The circuit has a pair of switch elements sequentially operable to place a resistor in circuit relation with a relay to effect its actuation, and the relay controls the energization of a coil of a clutch device for coupling it in driving relation with a refrigerant compressor operable in the system. A method of controlling an electrical circuit is also disclosed.

Variability reduction: statistically based algorithms for reduction of performance variability of electrical circuits

Abstract: A number of algorithms are presented for the reduction of circuit-response variability arising from component tolerances. A Monte Carlo analysis is carried out in the tolerance region and the responses F and differential response sensitivities ∂F/∂pi with respect to circuit parameters p calculated at each sample point. This enables both the variance of the responses and the circuit yield over the tolerance region to be estimated. At a given iteration, a descent direction for variance is determined by one of a number of different methods, and a suitable step length for the movement of the nominal point calculated. These two operations make extensive use of linear approximations to the response for the estimation of variance and yield for known displacements in the circuit parameters. As a consequence, the method is very efficient (∂F/∂pi are inexpensive to compute), since the number of fresh circuit analyses is kept to a minimum.

Circuit Analysis and Simulation Programs -An Overview-

Abstract: The paper is intended to be a tutorial-like description of the development of electrical circuit analysis programs used for analyzing digital and analog circuits. The anatomy of circuit simulator programs, analysis formulation techniques, and solution procedures will be addressed. A few of the features, capabilities, and limitations of several of the more widely used current programs will also be covered.

Analysis for the electrical circuit of tokamak discharge and computation of its current form

Abstract: By assuming an infinite iron core and its uniform magnetization, the vector potential and fields produced by a pair of current rings and a pair of cylindrical current shells are computed The total magnetic flux through each loop and the change rate of this magnetic flux are also computed The equations which combine the loop equations and the energy balance equations are presented The discharge current of HL-I device is computed with these equations

Electrical circuit and method of operating such

Abstract: An electrical circuit adapted to control the operation of a refrigerant compressor in an automotive type air conditioning system. The electrical circuit has a pair of branch circuits, an impedance for connection in the branch circuits so as to be respectively energized and shunted therein, and condition responsive devices for enabling and disenabling one of the branch circuits. Switching means is operable for sequentially energizing and then shunting the impedance in the branch circuits to control the energization thereof subject to the enablement and disenablement of the one circuit branch by the condition responsive device. A method of operating an electrical circuit to control the operation of a refrigerant compressor in an automotive type air conditioning system is also disclosed.

Solid-state load protection system having electronic simulation of motor heating

Abstract: A solid-state load protection system having electronic simulation of motor heating characteristics. A current sensing function is utilizes so as to produce an output signal which is related to the current in an electrical circuit. Attached to the current sensing function is an inverse time delay circuit and has a signal path for charging and discharging a capacitor. The voltage across the capacitor is related to the thermal state of the load. Depending upon the voltage across the capacitor, the inverse time delay circuit which is essentially an overcurrent and timing function which is monitoring the voltage will initiate either a time-out or trip sequence or a reset sequence. The time before time-out or reset is proportional to the voltage across the capacitor. An output function which is connected to the overcurrent and timing function upon receiving a trip signal causes a light emitting diode to conduct and also deenergizes a contactor through which a current source is connected to the load. Upon receiving a reset signal the output function prohibits the light-emitting diode from conducting and energizes a contactor thereby connecting the current source with the load.

Analysis of power takeoff in diagonal conducting wall channels

Abstract: An analysis of diagonal-conducting-wall MHD channels leads to design principles for the power takeoff and good quantitative agreement with experimental data. The effect of power takeoff schemes on the output power level is investigated analytically. It is found that it is possible to design the electrical circuit of the channel with passive elements in the takeoff region, and, achieve a fairly even load current distribution under changing load conditions without loss of power output.