Optimisation of Electromagnetic Components of a Parametrical Voltage Stabilizer with Magnetic Communications between the Nonlinear Coil and a Ballast Element

Optimisation of electromagnetic components of a parametrical voltage stabilizer with magnetic connections between the nonlinear coil and a ballast element on the minimum volume of an electromagnetic element Is resulted. Suitability for optimisation of criterion of equality of losses in core and device windings is considered. Analytical expressions for restrictions in the form of density of a current and an admissible overheat are received. The comparative estimation of use of active materials in the given device and the optimum transformer is made. KEYWORDS: a ferromagnetic element, approximation, core volume, current density, a magnetic induction, an overheat, losses in core, losses in the windings, full electromagnetic power, criterion function, restrictions, thermal balance.

Flux Reflection Model of the Ferroresonant Circuit

The paper presents a linear model of ferroresonant circuit with flux reflection. The proposed model—flux reflection model—derives from observations of typical flux waveforms of nonlinear coil during ferroresonant steady states. Simulation results of the flux reflection model are compared with simulation results of the usual nonlinear model as well as with measurements carried out on the physical model of the ferroresonant circuit. The flux reflection model enables a novel comprehension of the ferroresonant circuit behavior and simplifies the modeling of the nonlinear coil in the ferroresonant circuit.

Study on a Variable Stiffness Mechanism Using Wire Spring

In this paper, we propose a variable stiffness mechanism using wire springs. We have proposed such kind of mechanism using nonlinear coil springs. We intend to apply it to continuous passive motion (CPM) machine. It can change the spring characteristic continuously. Its disadvantages are need for wide space and powerful motor to change stiffness. And, it is difficult to design such nonlinear spring. To solve these problems, we propose a mechanism with wire springs. It is easy to obtain the wire spring, because it is material of coil spring. We explain how the design and evaluate it in experiments.