US 4,896,091 A · Electric power converter

Abstract

The power converter (10) serves for conditioning an electricity supply for a load (12), whereby the supply is derived from a power source (11) and is adapted to the requirements of the load (12) in respect of the electrical values. The converter (10) comprises in its simplest version exclusively a transformer (13) and an inductive resistor connected in series with the latter and designated as an actuator (14). This actuator (14) is constructed from two coaxially-arranged, identical and annularly closed variety cores (111, 112), which are individually surrounded by partial windings of an induction winding (150) and jointly by a control winding (117). The latter (117) is joined to a control system (30), which by means of a control current (I) sets an inductivity value (L) of the actuator (14), which can be varied within wide ranges (1.100). The actuator (14) acts with its appropriate inductivity value (L) on the alternating current (i) passing through its induction winding (150) in the same way as a conventional choke of an equivalent inductivity value (L), in other words, without any distortion. The in-series arrangement of the actuator (14) and transformer (13) thus has, on the alternating current (i), the action of a pure, electrically adjustable voltage divider.

Claims13

Dependent claims

An electrical power converter,

comprising a power transformer which separates galvanically a power source at its primary side from a load at its secondary side,
and comprising a final control element, the regulating actuator unit of which is a variable linear inductor and which regulating actuator operates linearly relative to an electrical voltage applied or relative to an electrical current applied to the regulating actuator, which regulating actuator has a finite inductance value which value can be measured at the input of the regulating actuator where the reactance of the regulating actuator is controllable by varying the value of the inductance;
where the ratio of the minimum of said inductance and the maximum of said inductance is settable relative to said electrical voltage applied or relative to said electrical current applied to the regulating actuator over values having a ratio of at least 1:100 by varying a control current.

An electrical power converter comprising

a power transformer;
a final control element;
a single control;
wherein the power transformer transforms the electrical power from its primary winding to its secondary winding and it separates galvanically its two sides;
the final control element influences the value of the electrical power fed from the input side of the converter to the output side of the converter;
wherein the function of the control element is that of a variable linear inductor, which means that the DC resistance of the element is zero (R.sub.DC =0), the AC resistance of the element is R.sub.AC =w.L, wherein w=angular frequency, w=2 pi f;
f measured in Hertz, L=inductance, measured in Henry;
which means the variable linear inductor has no electrical losses and it is a non-dissipative element;
wherein the control element operates as a variable linear inductor and does not distort the individual harmonics of the waveforms of the electrical parameter values;
wherein the control element comprises two identical ferromagnetic cores which are independent from each other and co-axially disposed, and each of said cores is annularly closed, a control winding which winds around the two identical ferromagnetic cores jointly, and an induction winding which winds around the two cores individually in a configuration of two partial windings connected in series, in such a way that magnetic fluxes, created by currents running through the windings in the cores are uni-directional in one of the cores and inverse-directional in the other one of the cores, wherein a functional dependence of the magnetic flux density B on the magnetic field strength H for a soft magnetic core material exhibits a curvature that has a progressively varying incremental permeability over its full region and thus substantially identical in its flux versus field strength curve for increasing and for decreasing field strength, and whose slope varies at least over values having a ratio of 1:100;
wherein the single control is controlling the final control element via a control current fed into the control winding of the element.

8 more elements

Dependencies are inferred from the claim text.

Electric power converter

Life of this patent

Electric power converter

Life of this patent

Abstract

Claims13