WO2003019584A1

WO2003019584A1 - The method to obtain energy from ferromagnetic material

Info

Publication number: WO2003019584A1
Application number: PCT/PL2002/000063
Authority: WO
Inventors: Jerzy Brzozowski; Dariusz Brylinski
Original assignee: Jerzy Brzozowski; Dariusz Brylinski
Priority date: 2001-08-27
Filing date: 2002-08-23
Publication date: 2003-03-06
Also published as: KR20040036728A; PL349299A1; HUP0401628A2; CN1547751A

Abstract

In accordance with the method of obtaining effective energy from the ferromagnetic material which is the core of electromagnet, its winding is supplied with electric current with such intensity that it causes magnetic saturation of the core, and after the work of attracting the armature is done, the supply is disconnected without loss of passive energy accumulated in the electromagnet inductance. A resonant impulse power supply is used to supply the electromagnet.

Description

The Method to Obtain Energy from Ferromagnetic Material

The subject of this invention is the method to obtain energy from ferromagnetic material constituting the material of the magnetic core of electromagnet.

The manner of operation of the electromagnet is known, it is the simplest electric machine transforming electric energy into mechanic energy that is the movement of the electromagnet armature towards electromagnet poles. At the time of closure of the current circuit with electromagnet, current starts to increase gradually to the value limited by the resistance of the electromagnet winding and the voltage forcing current in electric circuit. The rate of current increase depends on the inductance of electromagnet winding: higher inductance causes slower current increase and lower inductance - faster increase. Long time necessary for the current to become steady in the induction receiver - electromagnet is the result of activity of the electromotive force of self- induction. It is voltage induced in electromagnet winding under the influence of magnetic flux in its magnetic core. This voltage is directed opposite to the voltage feeding the circuit with electromagnet in the case of increase of the magnetic flux in electromagnet magnetic core and consistent with the direction of the supply voltage in the case of decrease of that flux. In practice, the effect is the following: when the power supply is switched on, the current in electromagnet slowly increases and when the power supply is switched off, on the terminals of electromagnet coil high voltage appears which causes spark-over on the element breaking current in electric circuit. During increase of the current in electromagnet coil, in its magnetic core energy is accumulated which is directly proportional to inductance in magnetic core, cross-section area of magnetic core, number of turns in electromagnet coil and the current in the coil. When the current circuit with electromagnet is switched off, the energy dissipates resulting in spark-over on the terminals of current breaker or is dissipated in the form of heat generated on the electromagnet winding resistance. For this purpose, electromagnet winding leads are short-circuited simultaneously with the break of electric current circuit containing the electromagnet. It is energy lost and it impairs the energetic balance of the electromagnet. After the current becomes steady with fixed value of the electromagnet winding, between its poles there is fixed magnetic field. If within the area of this magnetic field there is electromagnet armature, the electromagnet will attract it to its magnetic poles. The electromagnet armature will assume such final position so as the largest part of the magnetic flux would pass through the ferromagnetic material of the electromagnet armature. The magnetic force acts so as to close the way of the magnetic flux in the magnetic core material composed of the electromagnet core and the electromagnet armature because they have higher magnetic permeability than the air. Motion of electromagnet armature towards electromagnet poles results in decrease of magnetic reluctance and increase of the magnetic flux in magnetic core, and this, in turn, results in induction of electromotive force in the electromagnet winding which decreases current in the electric circuit. Lower current in the electromagnet winding means lower magnetic energy in the magnetic core material. Electromagnet operation, attraction of the electromagnet armature, was made at the cost of magnetic energy contained in magnetic core. After the electromagnet armature is attracted by electromagnet the electromagnet armature motion ceases and the electromotive force o^'f self- induction ceases to act. At this moment, current in the electric circuit is lower than it should be in steady state and increases to the value determined by the supply voltage and the resistance of the electromagnet winding. The rate of current increase depends on inductance of the electromagnet winding. The magnetic energy in the magnetic core increases to the initial state. Transformation of electric energy into mechanic energy is made through the mediation of magnetic energy contained in the magnetic core material and this transformation is conditioned by the induction of electromotive force of self-induction in the electromagnet winding.

We know impulse power supplies of electric circuits with inductive character -resonant power supplies. Such power supply forces fast current increase in the induction receiver by an high-voltage impulse, and then supports current in the receiver by low voltage. At the moment of disconnecting the sup- plied circuit, the energy contained in the magnetic core of the induction receiver is accumulated on the condenser under a high voltage. High voltage on the condenser is used with reconnection of the induction receiver until fast current increase is reached.

The essence of the manner of generation of effective energy from the ferromagnetic material of the electromagnet core is as follows: before starting work by electromagnet the current in its winding reached the value at which the magnetic field strength in the magnetic core is higher or equal to the field strength causing magnetic saturation of the magnetic core material, performance of work by electromagnet, i.e. attraction of the electromagnet armature with deepening magnetic saturation of the magnetic core material and disconnection of the electric circuit with the electromagnet without loss of energy accumulated in it.

The solution according to the invention is. characterized by the fact that during performance of work by the electromagnet in the magnetic core, no essential changes appear of the magnetic flux, and what follows, in the winding of the electromagnet the electromotive force is not induced. With the magnetic saturation of the magnetic core material the magnetic flux in it is the maximum and remains on a steady level with decrease of the air-gap between the core and the electromagnet armature. Decrease of the air-gap is caused by the movement of the electromagnet armature towards the electromagnet poles under¹ the influence of magnetic attraction. Thus, there are no conditions necessary for the transformation of electric energy into mechanic energy in spite of the fact that under these conditions electromagnet affects the electromagnet armature with the highest possible force. The entire electric energy consumed by electromagnet is dissipated on the resistance of the electromagnet winding, and the passive energy introduced at the first work cycle of electromagnet, in the next cycles oscillates between the electromagnet and the condenser in which it is accumulated at the time of completion of the work cycle .

The unavoidable losses of passive energy are supplemented by the supply source with each electromagnet disconnection.

The method according to this invention is explained in more detail on the drawing - where fig. 1 presents the diagram of the impulse resonant power supply of the electromagnet, and fig.2 - a diagram of the electromagnet work cycle.

Electromagnet supply according to fig.l is implemented as follows: electromagnet L is supplied from the electric energy source Uz through diode Dl. The keying element is transistor V. The leading edge led to the gate of transistor v also releases thyristor Ty_ through the differentiating circuit R2 ,C2, transformer Tr and diode D3. Diode D4 enables discharge of the energy accumulated in the primary winding of transformer Tr and resistor Rl decreases the thyristor' s Tr sensitivity to disturbances. Simultaneous connection of transistor V and thyristor Ty_ allows to discharge the condenser CI in the circuit: +C1, Ty_, L, V, -CI. With the first control impulse the condenser ci is not charged and the closure of this circuit will not result in the passage of current in the above-mentioned electric circuit. Simultaneously to control of transistor v, current starts to pass from +τjz through Di, and V to -Uz . The current increases from zero to the value limited by the resistance of winding of L and voltage Uz, under the condition that the control impulse is sufficiently long and remains on the fixed value until this electric circuit is broken by the trailing edge of the control impulse. During increase of the current in electromagnet L, magnetic energy accumulates in it. The trailing edge of the control impulse breaks the circuit of the current passing through transistor v, but the electromotive force induced in the winding of electromagnet L and the supply voltage source connected in series with it force the passage of current in the circuit: +Uz, L, D2, Cl, -Uz charging the condenser c to the voltage higher many times than the voltage of the supply source Uz. Passage of current in this circuit ceases upon complete discharge of the energy contained in the inductance of L. At this moment the voltage on the condenser has the maximum value and the entire system is ready to be reconnected. Passive energy stored in the electromagnet magnetic core was recovered and is accumulated on the condenser C under a very high voltage. The leading edge of the next control impulse at the same time connects transistor V and transistor Tv but current passes only in the circuit +C1, Ty, L, v, ^≤ because the high voltage of the condenser Cl causes back bias of diode Di and the supply source Uz is cut off from the electric circuit until the voltage on condenser Cl drops below the supply voltage Uz reduced by the voltage decrease o diode Dl. Now, diode Di is polarized towards passage and the source of the supply voltage Uz supports the earlier forced current value in the circuit:

+Uz, Dl, L, V, Uz.

If with such power supply of the electromagnet the appearance of the electromotive force in the electromagnet winding is made impossible during attraction of the electromagnet armature by electromagnet, the conditions will be created under which performance of effective work by electromagnet is not connected with transformation of electric energy into mechanic energy. With small losses of the oscillating passive energy nearly entire power supplied from the supply source is transformed into heat on the resistance of the winding and electronic switching elements .

The first method of limiting or eliminating the electromotive force in the electromagnet winding performing mechanic work is based on the selection of the passage of cur- rent, that is the product of the number of coils in the electromagnet winding multiplied by the current supplying the winding, in such a way that the core material becomes saturated magnetically with the largest foreseen air-gap between the core and the electromagnet armature.

It is explained by fig.2 presenting the electromagnet, consisting of the core 3 and winding 6 and the electromagnet armature 1 in the position in the time tO before the start of movement towards the electromagnet poles and the same electromagnet armature 2 in the position in the time tl after completion of the work by electromagnet. Flux F passing through core 3, air-gap of 1 and the electromagnet armature 1 in time tO is equal to flux F in time tl after the electromagnet armature 2 is attracted to the core 3. Decrease of gap of 1 to zero cannot cause change of the magnetic flux F because in time tO the flux F already achieved the maximum value and cannot be any higher. The value of the induced electromotive force is directly proportional to flux changes in time unit. If the change of flux F is close to zero then also the electromotive force induced is close to zero.

Fig.3 presents the second method of decreasing or eliminating the electromotive force in the winding 6 of the electromagnet moving the electromagnet armature 1 by the force of its magnetic field of F - fig.3A to the final position 2 - fig 3B. In this case the steadiness of flux F at the time of movement of the electromagnet armature is ensured by the constant length of gap lo. The electromagnet armature movement is simultaneous to the plane of the magnetic poles of electromagnet. In this case also changes of the magnetic flux close to zero do not cause induction of the electromotive force in the winding 6 of electromagnet.

Claims

1. The method to obtain energy from soft ferromagnetic material, which is the material of the core and the armature of the electromagnet magnetic core, consisting of performance of effective work by the electromagnet attracting the armature to the magnetic poles of the core while supplying its winding with the electric current characterized by the fact that the electromagnet winding is supplied with electric current higher than or equal to - with a specific number of coils in the electromagnet winding - the current of magnetic saturation of the ferromagnetic material of the core and the electromagnet armature, and after the current value becomes steady and the core and electromagnet armature are saturated magnetically the work of attracting the armature in perpendicular direction to the plane of the magnetic poles of electromagnet core is done, and after that work the current circuit with electromagnet is broken and the energy contained in electromagnet inductance is accumulated in the form of high voltage electric charge on the condenser; the high voltage forces fast current increase in the electromagnet winding with its re-connection to the electric current circuit.

2. The method of obtaining energy from soft ferromagnetic material, which is the material of the core and the magnetic core armature of the electromagnet, consisting of the performance of effective work by the electromagnet attracting the armature to the magnetic poles of the core during supplying its winding with electric current characterized by the fact that the electromagnet winding is supplied with electric current the work of attracting the armature to magnetic poles of the electromagnet core in the direction parallel to the plane of the poles is done, and after this work is done, the current circuit with electromagnet is broken and the energy contained in the electromagnet inductance is accumulated in the form of high voltage electric charge on the condenser; the high voltage forces fast current increase in the electromagnet winding with its reconnection to the electric current circuit.

3. The method according to reservations 1 and 2 characterized by the fact during performance of work of attracting the armature by electromagnet, steady value of the magnetic flux is maintained in the electromagnet magnetic core composed of the core, the armature and the air-gap between the core and the armature .