SU920248A1 - Semiconductor voltage converter for ignition system - Google Patents

Description

(54) SEMICONDUCTOR VOLTAGE CONVERTER FOR IGNITION SYSTEM

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The invention relates to converter technology and can be used, for example, for the ignition system of internal combustion engines.

Semiconductor converters are known that contain a power transformer, the midpoint of the primary winding of which is connected to one of the poles of the energy source, and the extreme clips to the same electrodes of controlled semiconductor devices, the other electrodes of the same name connected to the other pole of the energy source 1.

However, these converters are characterized by the presence of unacceptable overvoltages on semiconductor elements.

The closest to the technical essence of the invention is a semiconductor n () generator for an engine combustion system for internal combustion engines containing a multivibrator and an amplifier, as well as a step-up power transformer, the midpoint of the primary winding of which is connected to one of the poles is. energy point, and the extreme clips of the primary winding - to the collectors of transistors.

whose emitters are connected to another pole of the energy source.

One of the features of the known converter is that the extreme terminals of the primary winding of the transformer are connected to the anodes of the diodes, and the common connection point of their cathodes is connected both to the midpoint of the primary winding of the power transformer and to the positive terminal of the power source. Such a connection of the diodes to the primary winding of the power transformer avoids unacceptable overvoltages of the power transistors connected to this winding when they are locked due to the magnetic field energy released by the stored half of the primary winding of the transformer. In the circuit of the known converter, conditions are created for the further passage of current through this half of the winding and the diode inducing it under the influence of the stored energy of the magnetic field in the inductance of the seeding.

However, the further passage of the winding half unchanged in the direction of the current to the current to the power transistor

A power transformer of a known converter creates in its core a magnetic flux directed oppositely to the main magnetic flux created by the source voltage, applied in this case to the other half of the primary winding through its power transistor. This leads to a relative increase in the current in the half of the transformer winding connected to the source, which leads to an increase in losses in the power transformer and deterioration of the energy performance of the converter, i.e. Efficiency, as well as to the relative overestimation of the typical power, the deterioration of the weight and dimensions of the power transformer and power transistors.

The purpose of the invention is to improve the energy performance, i.e. efficiency increase.

The goal is achieved by the fact that in a semiconductor voltage converter for the ignition system of an internal combustion engine, there is a multivibrator with an amplifier and a power amplifier, with a power transformer, the midpoint of the primary winding of which is connected to one of the poles of the energy source, and extreme leads to collectors of transistors, the emitters of which are connected to the other pole of the energy source, with the secondary winding of the power transformer connected to distribute The ignition switch, to the extreme terminals of the primary winding of the step-up power transformer, is connected to the primary winding of an additional transformer, the secondary winding of which is connected in series with the secondary winding of the power transformer.

The drawing shows a schematic diagram of the proposed Converter.

The semiconductor converter contains a power transformer 1, the primary winding of which is divided into parts 2 and 3, the middle point of the primary winding is connected to the positive pole of energy source 4, its extreme leads are to the collectors of power transistors 5 and 6, the KQTopbix emitters are connected to the negative pole of energy source 4 . The extreme terminals of the primary winding of the step-up power transformer 1, divided into parts 2 and 3, are also connected to the primary winding 7 of an additional transformer 8, the secondary winding 9 of which, together with the secondary winding 10 of the power step-up transformer 1 connected in series with it, is connected to the spark plugs 12 The control inputs of the power transistors 5, the power amplifier are connected to the multivibrator with the amplifier 13.

The Converter operates as follows.

Unlocking the transistor 5 leads to the formation of a current circuit, the positive pole of the power source 4 - the middle point of the primary winding of the power transformer 1 extreme end of part 2 of this primary winding - an open transistor 5 - the negative pole of the power source 4; the knowledge of the EMF on the secondary winding 10 of the power transformer 1; to induction of EMF and voltage as a series connection of parts of the primary winding

2 and 3 of the power transformer and in parallel with the connected primary winding 7 of the additional transformer 8, and the secondary winding 9 of this transformer. Next, the previously open transistor 5 is locked. In the next time interval, the current continues to flow through the circuit; the positive pole of source 4 is the middle point of parts 2 and 3 of the primary winding of the power transformer - part 2 - primary winding 7 of the additional transformer 8 - other part 3 of the primary winding of power transformer 1; the previously stored energy in the inductance of the primary winding of the power transformer 1 through the primary winding 7 of the additional transformer 8 and its magnetic system is transmitted to the secondary winding 9, which increases the resulting voltage of the secondary circuit of the windings 9 and 10, i.e. Ani 12. Next is the unlocking of the power transistor 6, which leads to: the formation of a current circuit through the positive pole of the source 4, the middle terminal of the primary winding of the power transformer 1, the extreme terminal of its part 3, open 6th transistor, negative pole of power source 4; to induction of the EMF of the opposite polarity as compared with the previous time interval both in parts 2 and 3 of the primary winding of the transformer 1 and in its secondary winding

10 and the secondary winding 9 of the additional transformer 8, since its primary winding 7 is connected to the extreme terminals of the primary winding of the power transformer 1.

However, the highest voltage on the series connection of the secondary windings 10 and 9 of transformers 1 and 8 is observed in the subsequent time interval after locking the previously opened transistor 6, prior to unlocking the power transistor 5. During this time interval, the current continues to flow through the primary windings of both transformers connected to each other I and 8, which leads to the utilization of previously stored energy in the magnetic field of transformer 1, due to its transfer to the secondary circuit through an additional transformer or 8 to achieve the maximum voltage across the series connection of the secondary windings 9 and 10 of transformers 1 and 8. Next, transistor 5 opens and the processes are repeated.

The peculiarity of this semiconductor converter allows to utilize the energy of the magnetic field previously stored in the magnetic field of individual parts of the primary winding of the power transformer, to improve the use of the power transformer and power transistors. The possibilities of improving the weight and size parameters of a power transformer, which open up due to this, allow us to hope that even the introduction of an additional transformer in the device does not impair its weight and size parameters as compared to the known ones.

Claims (2)

1.Japanese patent number 53-39570, cl. 56 C 61, 1978. 0 2. Author's certificate of NRB (Brlgari) No. 19507, cl. F 02 p 3/00, 1978. 12