Autoconverter with improved charging switch system

Claim 2

An autoconverter, comprising: a charging capacitor connected to a d.c. source via a charging diode and a charging inductor; a charging switch periodically closed by a signal from a control means with a given pulse-duty factor; the charging switch periodically connecting the charging inductor to the d.c. source; two series connected alternately driven first and second switches connected parallel to the charging capacitor; means for synchronizing the control means for the charging switch by a square wave voltage at the first switch such that the charging switch is closed as a result of a voltage across said first switch when it is inhibited and is opened after a time defined by charging of a delay means to a response valve; a discharge circuit of the delay means being conducted through the first switch; the charging switch comprising a power MOS transistor having a control lead connected to a controllable switch and also to a series capacitor; the series capacitor and controllable switch forming a series connection connected parallel to the first switch; and said controllable switch being driven into a closed position via a threshold element means as a function of a voltage at said delay means.

Claim 3

The autoconverter according to claim 1 wherein the delay means comprises a storage capacitor.

Claim 4

An autoconverter according to claim 1 wherein the capacitor connected to the control lead of the MOS power transistor is dimensioned such that a sufficiently fast charging of a capacitance associated with the control lead of the MOS transistor is assured.

Claim 5

An autoconverter, comprising: a charging capacitor connected to a d.c. source via a charging diode and a charging inductor; a charging switch periodically closed by a signal from a control means with a given pulse-duty factor; the charging switch periodically connecting the charging inductor to the d.c. source, two series connected alternately driven first and second switches connected parallel to the charging capacitor; means for synchronizing the control means for the charging switch by a square wave voltage at the first switch such that the charging switch is closed when said first switch opens and is opened after a time defined by charging of a delay means to a response value; a discharge circuit of the delay means being conducted through the first switch; the charging switch comprising a power MOS transistor having a control lead connected to a controllable switch and also to a series capacitor; the series capacitor and controllable switch forming a series connection connected parallel to the first switch; said controllable switch being driven into a closed position via a threshold element means as a function of a voltage at said delay means; the d.c. source being a rectifier means supplied from an a.c. line which supplies an unsmoothed half-wave voltage, a pulse-duty factor depending on the voltage at the charging capacitor; and for generating a sinusoidal line current dependent on a correction quatity derived from the half-wave voltage of the rectifier means, the delay means being connected in parallel over a resistor to a first capacitor which together with a second capacitor forms a voltage divider that is connected parallel to the rectifier and is dimensioned such that it is substantially active at twice a frequency of an a.c. voltage feeding the rectifier means and represents a shortcircuit for higher frequency noise voltages.

Claim 6

An autoconverter, comprising: a charging capacitor connected to a d.c. source via a charging diode and a charging inductor; a charging switch periodically closed by a signal from a control means with a given pulse-duty factor; the charging switch periodically connecting the charging inductor to the d.c. source, two series connected alternately driven first and second switches connected parallel to the charging capacitor; means for synchronizing the control means for the charging switch by a square wave voltage at the first switch such that the charging switch is closed when said first switch opens and is opened after a time defined by charging of a delay means to a response value; a discharge circuit of the delay means being conducted through the first switch; the charging switch comprising a power MOS transistor having a control lead connected to a controllable switch and also to a series capacitor; the series capacitor and controllable switch forming a series connection connected parallel to the first switch; said controllable switch being driven into a closed position via a threshold element means as a function of a voltage at said delay means; the d.c. source being a rectifier means supplied from an a.c. line which supplies an unsmoothed half-wave voltage, a pulse-duty factor depending on the voltage at the charging capacitor; and for generating a sinusoidal line current dependent on a correction quatity derived from the half-wave voltage of the rectifier means, the delay means being connected in parallel over a resistor to a first capacitor which together with a second capacitor forms a voltage divider that is connected parallel to the rectifier and is dimensioned such that it is substantially active at twice a frequency of an a.c. voltage feeding the rectifier means and represents a shortcircuit for higher frequency noise voltages.

Claim 7

An autoconverter according to claim 4 wherein the charging capacitor is part of the voltage divider.