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A novel two-objective optimization design model of the solenoid coil SMES system is described. The algorithm has generated Pareto solutions and the results have suggested an adaptive constraint handling method can be integrated into NSGA-II seamlessly.

A novel two-objective optimization model of the solenoid coil design is described. The results have shown that the algorithm has provided a set o feasible Pareto solutions, among which the best one is extracted according to the designer's experience.

In this paper, a physical model is presented to predict the frequency-dependent characteristics of solenoid-type inductors on standard silicon substrates. The model considers the skin-depth effect in the conductor, interwinding capacitance, parasitic capacitance between the conductor and substrate, substrate resistance, and substrate capacitance of a solenoid inductor on the silicon substrate, which are all computed based on the inductor's geometric dimensions and related material properties. Surface-micromachined inductors of various geometries have been tested to validate the physical model and found a satisfactory consistency between the measured results and the theoretical predictions in the multigigahertz frequency range. It is also suggested that the increase of the solenoid aspect ratio is beneficial in enhancing quality factors of solenoid inductors on the silicon substrate at a high frequency. Index Terms--Inductor model, quality factor, self-resonance, silicon, solenoid inductor, substrate loss, surface micromachining.

Instrumentation in the vacuum chamber in the Central Solenoid Model Coil and the CS Insert coil operation is investigated.

Preload structure and variations in preload of the Central Solenoid Model Coil operation are examined.

The International Thermonuclear Experimental Reactor central solenoid model coil conductors were studied to determine predicted thermohydraulic performance.

Legendre polynomials have been used in studying the stray field outside a solenoid. The stray field outside a thin solenoid coil can be expanded in a series of Legendre polynomials in cylindrical coordinate where an observation point is designated as R(sub p).Results indicate that the term of a stray field decreasing as r(sub p) raised to the negative third power can be cancelled out as long as the summation of magnetic moments from all coils is zero. The higher order of the stray field can vanish if the coil arrangement is optimized.

A magnetostatic integral equation for the current induced by a solenoidal inductor in the conducting wall of a closed, perfectly conducting cylindrical shield was solved by the method of moments and point matching. The induced current was then used to determine the self inductance of the solenoid. A chart of the ratio of the shielded inductance to that in free space was produced to aid in the design of practical air-core inductors. In addition, Wheeler's well-known formula for the free-space inductance of a single-layer solenoid was shown to be sufficiently accurate to serve as a basis for the design of practical coils if the effect of the shield, available from the chart, is included. Index Terms - Conducting shield, inductance, solenoid, very low frequency.

The ITER shear key system is designed to interconnect neighboring toroidal field coils at their inner portions. Due to these keys the coils inner portions resist the torque as a whole structure. On the other hand, the ITER magnet system design provides supporting of the centering load on the TFC by a bucking cylinder. Hence, the keys should not produce any significant wedging during the radial movement of the coils. Numerical modeling of the so called scissors' action keys that satisfy above requirements has been performed with assembly gaps being taking into account. Cooldown, TFC energizing and poloidal fields coils pulse regimes have been studied. Since the TFC torsion produces high cyclic compression on the key ground insulation, the electrical insulation testing is required. Two mock-up systems for this testing have been proposed and modeled. One system models an effect of the TFC radial movement resulting in higher peak compression on the insulation.

The 'GLOBUS-M' is a compact resistive tokamak with a central solenoid (CS) wound around the inner portion of the toroidal field coils. The magnetic field at the solenoid axis amounts to 8.3 T. The CS incorporates two layers of conductor (CuCr copper alloy) baked into insulation. The solenoid is designed to sustain 80.000 energizing. During each loading cycle the solenoid is subjected to the radial forces accompanied with the vertical compression. The most loaded region has been considered and modeled with the use of 2D axisymmetric finite element (FE) model. The model includes two conductor turns baked into insulation compound, copper cooling tubes and solder. The stress analysis shows that there is some plastic deformation in the copper tube and solder during loading and there is some back plastic deformation in the solder during unloading. The reloading does not cause any change in the solenoid stress-strain state in comparison with the case of loading. The number of cycles to failure has been simulated for all metallic components of the solenoid.

Dynamic modeling of solenoids is difficult because of the coupling of a nonlinear magnetic system, which includes eddy currents. The finite-element method has been successfully implemented to solve this complex problem. However, the large computer time requirements associated with numerical solutions make this approach cumbersome to use, especially during the design stage, where repeated design trials are necessary. Also, few papers refer to the deenergizing state of solenoids. By introducing appropriate assumptions, the author developed a set of equations which requires small amount of computer time to execute. These equations describe the deenergizing state of solenoids and perform test results satisfactorily. Index Terms - Solenoid, Eddy Current, Dynamic Model, Magnetics

This paper presents a lumped parameter equivalent circuit model for cylindrical, induction-type, electromagnetic coil-launchers based on an electromagnetic field transmission-line approach. Basic closed-form formulas for performance analysis are derived from the model. System parameters and performance indices are obtained from the circuit model and related to the dimensions of the launcher. Currents in the linear array of barrel and projectile (sleeve) conductors are represented by two voltage-controlled current sources. If the barrel and sleeve are approximated by two equivalent cylindrical current sheets, then the circuit model becomes simplified, the Bessel function arguments become real, and the barrel may be modeled by a single constant voltage source. A modified planar model is also considered. Limitations of each level of approximation are presented. Formulas for determining the electrical time constants of the launcher are included. Data from experiments with a small model are compared with calculated results.

PWM (Pulse width modulated) solenoid valves posses the advantages of low cost, high flow rate gain, and simple structure. However, the use of a PWM solenoid valve causes both discontinuity and nonlinearity of the flow rate; this results in difficulties of modeling and of control. This paper presents our work on modelling a pneumatic PWM solenoid valve for engineering applications. Two models are presented: one is the instantaneous mass flow rate model which can be used in the simulation to study the dynamic behavior of pneumatic PWM control systems; another model is the equivalent mass flow rate model which is developed for facilitating the synthesis of pneumatic PWM servomechanisms. An equation for determining the maximum operating modulation ratio of the PWM solenoid valve is also presented. Simulated results using the established models are compared with the experimental results for both the static characteristics of a PWM solenoid valve and the dynamic behavior of a system composed of a PWM solenoid valve and a constant volume chamber.