Tridonic Gmbh Co. Kg

Hans Auer

Frank Lochmann

Christoph Vonach

Andre Mitterbacher

Günter Marent

Patrick Marte

Harald Netzer

Peter Lampert

Stefan Stark

Lukas Saccavini

Martin Mohr

Clemens Kucera

Joan Ortega

Fabio Romano

Jan Pioske

Philip Rebhandl

Mathias DÜNSER

A converter () for operating an LED load is provided. The converter () comprises an actively switched power factor correction, PFC, circuitry (-), having a control circuitry (-) for controlling a switch () of the PFC circuitry (-). The control circuitry (-) is configured to control a switch-on timing of the switch () such that an output voltage (, V) of the PFC circuitry (-) is feedback-controlled in accordance with a nominal value (). In a discontinuous conduction mode, DCM, the control circuitry (-) is configured to control an actual value (, T) of the switch-on timing of the switch () in one or more switching cycles to be a time of a valley of a voltage across the switch () succeeding a nominal value (, T) of the switch-on timing of a control algorithm implemented by the control circuitry (-). The control circuitry (-) is further configured to control the actual value (, T) of the switch-on timing of the switch () in one or more subsequent switching cycles being subsequent to the one or more switching cycles to be a time of a valley of the voltage across the switch () preceding the nominal value (, T) of the switch-on timing. This reconciles valley switching and avoidance of visible light flicker.

PFC with valley controlled DCM for an LED load

The invention relates to an LED-driver, comprising an actively switched PFC circuitry and a bus interface for a wire-bound bus, wherein a voltage supply for the bus interface for powering the bus is tapped off the output voltage of the active PFC circuitry, further comprising a control circuitry for a feedback control of an output voltage of the actively switched PFC by controlling a switch of the PFC, wherein the time constant of the feedback control of the control circuitry is faster during time periods in which the bus interface is transmitting or receiving signals, compared to time periods without activity.

LED-driver with PFC and wired bus interface

The invention relates to a power factor correction (PFC) circuit (), comprising an inductor () which is configured to provide a discharge current, a capacitor () which is connected to the inductor () via a switch () and which can be charged with said discharge current, a control unit () which is configured to alternately switch the switch () on and off based on a feedback control, wherein the control unit () has an input interface () for receiving a feedback signal (ZXCS) which represents a discharge voltage of the inductor (), wherein the control unit (), in a DCM mode, is further configured to calculate a switch on time (T) of the switch () which is after a first local minimum of the discharge voltage, and wherein, after switching off the switch (), the control unit is configured to: either switch on the switch () at a next or closest local minimum of the inductor voltage after Ton, in case Ton is less than a directly or indirectly set reference time (T), or close the switch () at T, in case Tis equal to or exceeds T.

Power factor correction circuit

For the purpose of power factor correction, an inductance () is supplied with an input voltage (Vin), wherein a controllable switching means () that is coupled to the inductance () is actuated in order to selectively charge and discharge the inductance (). A control device () for actuating the switching means () is designed such that it actuates the switching means () selectively on the basis of one of a plurality of modes of operation. In a first mode of operation, a switch-on time is stipulated for the switching means () on the basis of a minimum waiting time and on the basis of a voltage that drops across the switching means ().

Method for controlling a power factor correction circuit, power factor correction circuit and operating device for an illuminant

A power factor correction circuit () comprises an input for receiving an input voltage (U), an inductance () coupled to the input, a switching means () that is coupled to the inductance () and that is controllable in order to either charge or discharge the inductance (), and a control device (). The control device () is set up in order to produce a control signal (Ctrl) for controlling the switching means () on the basis of a parameter value. The control device () is set up in order to ascertain the parameter value on the basis of an arithmetic sign of a time derivation for the input voltage (U).

Power factor correction circuit, operating device for a light-emitting means and method for controlling a power factor correction circuit

The invention proposes a method for operating an actively clocked PFC circuit () having a directly or indirectly connected load circuit () at the output of the PFC circuit (), wherein the load circuit () has at least one luminous means, in particular one or more LEDs (), wherein the PFC circuit () is controlled by a PFC controller () in such a manner that the PFC controller () determines a control parameter, in particular a switched-on time period (ton), for the clocking of the PFC circuit () on the basis of at least one first controller setting (RE_fast) and one second controller setting (RE_slow), wherein the time of a change from the first controller setting (RE_fast) to the second controller setting (RE_slow) is dependent on the directly or indirectly determined average value of the control parameter, in particular the switched-on time period (ton).

Control loop with a variable time constant for power factor correction for a load circuit comprising light-emitting means

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Dornbirn, Austria

Hans Auer