Abstract: A resonant power converter includes a resonance tank formed by a capacitance component and an inductance component, at least two switches connected to the resonance tank and a voltages source in a bridge configuration, a number of snubber capacitors connected in parallel to each of the switches, a controller configured to control ON and OFF timings of the at least two switches so as to excite the resonance tank, and a voltage sensor configured to sense a voltage drop across at least one of the switches. The controller is configured to switch the at least one of the switches to the ON state when the absolute value of the sensed voltage drop reaches a minimum.

Abstract: A battery charger for electric vehicles includes at least three identical current controlled AC-DC converter modules having reverse current protected outputs connected in parallel to a charge terminal of the battery.

Abstract: An LED driver circuit includes at least one string (10) of LEDs (12) connected in series, and a power supply for converting a mains voltage (AC) into an output voltage (Uout) to be applied to the at least one string (10) of LEDs, in which the power supply includes a single-stage boost converter (14) adapted to directly convert the mains voltage (AC) into the output voltage (Uout).

Abstract: A power supply circuit includes a number N, N?2, of parallel connected, cyclically switched electronic converters having outputs connected to a common output terminal; and a controller providing switching pulse signals switching the converters with a switching frequency that is the same for all converters; load circuits connected to the output terminal; a PLC transmitter modulating an output current from the output terminal; and a PLC receiver in each load circuit, the controller switching the converters with interleaved switching pulse signals; the PLC transmitter modulating the output current by switching the controller between at least two modes of operation that differ in phase relations and/or pulse shapes of the switching pulse signals, changing a ripple frequency spectrum of the output current such that a suppression amount of a predetermined frequency component is changed depending upon the mode of operation; and the PLC receiver detects the predetermined frequency component.

Abstract: A power supply circuit includes a number N, N?2, of parallel connected, cyclically switched electronic converters having outputs connected to a common output terminal; and a controller providing switching pulse signals switching the converters with a switching frequency that is the same for all converters; load circuits connected to the output terminal; a PLC transmitter modulating an output current from the output terminal; and a PLC receiver in each load circuit, the controller switching the converters with interleaved switching pulse signals; the PLC transmitter modulating the output current by switching the controller between at least two modes of operation that differ in phase relations and/or pulse shapes of the switching pulse signals, changing a ripple frequency spectrum of the output current such that a suppression amount of a predetermined frequency component is changed depending upon the mode of operation; and the PLC receiver detects the predetermined frequency component.

Abstract: An LED driver circuit includes at least one string (10) of LEDs (12) connected in series, and a power supply for converting a mains voltage (AC) into an output voltage (Uout) to be applied to said the at least one string (10) of LEDs, in which the power supply includes a single-stage boost converter (14) adapted to directly convert the mains voltage (AC) into the output voltage (Uout).

Abstract: A battery charger for electric vehicles includes at least three identical current controlled AC-DC converter modules having reverse current protected outputs connected in parallel to a charge terminal of the battery.

Abstract: A resonant power converter includes a resonance tank formed by a capacitance component and an inductance component, at least two switches connected to the resonance tank and a voltages source in a bridge configuration, a number of snubber capacitors connected in parallel to each of the switches, a controller configured to control ON and OFF timings of the at least two switches so as to excite the resonance tank, and a voltage sensor configured to sense a voltage drop across at least one of the switches. The controller is configured to switch the at least one of the switches to the ON state when the absolute value of the sensed voltage drop reaches a minimum.

Abstract: A boost converter comprising an optional RFI-filter, a boost inductor (LB), two switch transistors connected in series (t2, T3) and at least one diode (D6, D7). The boost inductor is connected in series with the switch transistors directly to the AC mains voltage for producing a boosted AC voltage. The boosted AC voltage is rectified by a voltage doubling circuit, or alternatively with a full bridge rectifier. A control circuit controls the switch transistors. By arranging the boost inductor in the AC part, the inductor can be made considerably smaller. Moreover, several diodes can be excluded, resulting in a high efficiency, especially at low mains voltages below 3 times the output DC voltage. The boost converter is suitable for a mains AC voltage of 80 to 140 V for a supply of 410 V DC.

Abstract: The invention relates to a DC/AC converter for supplying two gas discharge lamps, comprising a double bridge configuration of four switch elements, a third series circuit interconnecting the input terminals comprising a first capacitor and a second capacitor with substantially equal capacitance, a first and a second gas discharge lamp connected to the bridge configuration, wherein an inductor is connected in series with each of the lamps and a control circuit for controlling the switch elements and which is adapted to control the conducting periods of the switches with a duty cycle which is variable. By control of the conducting periods of the switch elements a proper control of the energy supplied to the lamps is obtained. Of course care should be taken to avoid the simultaneous closure of the first and second switch elements and of the third and fourth switch elements to avoid short circuits.

Abstract: A driver assembly (10) for driving a high-power gas discharge lamp (L) comprises a plurality of at least two low-power lamp drivers (1A, 1B, 1C) having their respective output terminals coupled in parallel, each individual driver (1A, 1B, 1C) being designed for generating a commutating DC-current at its respective output terminal, the assembly (10) comprising synchronisation means for synchronising the output currents of the individual drivers (1A, 1B, 1C).

Abstract: In a bridge circuit for operating a high pressure discharge lamp an additional switching element, a control circuit for driving the additional switching element, a resonant inductor and a resonant capacitor are incorporated. The additional components together form a comparatively simple resonant igniter. The resonant inductor can be formed by part of a filter comprised in the bridge.

Abstract: Circuit for driving a load, comprising: two input terminals for connection to a source of a supply voltage; a first and a second output terminal for connection to the load; at least one inductor coupled between one of the output terminals and a corresponding connection node; at least one arrangement comprising a switch coupled between one of said input terminals and one of said connection nodes, a diode being connected between said one connection node and the other input terminal; a control unit for controlling said one or more switches; wherein each arrangement and corresponding diode are designed to allow the voltage over the opened switch of said arrangement to return to substantially zero before said switch is closed, the control unit being designed to provide a signal for closing the switch when a substantially zero voltage over said opened switch is detected. Turning the switch on at a substantially zero voltage means that switching losses are greatly reduced, and this without complicating the circuit.

Abstract: A DC-AC converter in a half bridge configuration is used for operation with high pressure discharge lamps as well as low pressure discharge lamps. The converter consists in two switches (T1-T2) serially connected through a first series of diodes (D1, D2) and a second series of diodes (D3,D4) to which at their middle points (N1, N2) a first and a second lamp load (L1,L2,LA1,LA2) are connected. Furthermore, the second terminals of the lamp loads are connected to the middle point of a series of capacitors (C3,C4) which are also connected to the terminals (Ki,K2) of the supply voltage source. The converter includes also four diodes (D5,D6,D7,D8) which shunt the switches (T1,T2) and their respective series of diodes (D1,D2,D3,D4). The switches (T1,T2) are controlled by a controller (CC) which renders alternatively conductive at low frequency the two switches (Ti,T2).

Abstract: Driver (150) for a gas discharge lamp (9) comprises: an arrangement of two MOSFET switches (61, 62) connected in series between two input terminals (51a, 52b); an inductor (73) connected in series with said lamp (9), this series arrangement being coupled to a node (P) between said two switches; a control unit (180) providing control signals (S1, S2) to said two switches. During a first commutation interval (41), a lamp circuit current (ILC) has only a first direction while during a second commutation interval (42) said lamp circuit current has only an opposite direction. In each commutation interval (41, 42), during a first operational phase (43) said lamp circuit current has a continuously increasing level while during a second operational phase (44) said lamp circuit current has a continuously decreasing level. The control unit (180) is designed to generate its control signals (S1, S2) such that said two switches are always, switched substantially simultaneously in counter-phase.

Abstract: In a ballast circuit for supplying a high pressure discharge lamp and comprising an up-converter and a bridge circuit, the output voltage of the up-converter is controlled at a higher level immediately after the ignition of the lamp and at a lower level during stationary operation. Stabilization of the discharge immediately after ignition of the lamp and a relatively small power dissipation are both realized in this ballast circuit.

Abstract: The invention relates to a circuit for a discharge lamp, comprising: a first sub-circuit for connecting to mains voltage of a predetermined frequency for rectifying the mains voltage; a second sub-circuit connected to the first sub-circuit for providing an alternating current, preferably a square-wave current, required for the lamp; and a control circuit which is connected to the first and the second sub-circuit and which controls the frequency of the alternating current subject to a varying component of the mains voltage rectified by the first sub-circuit.

Abstract: The present invention relates to a switch mode power supply for igniting and operating a high-pressure gas discharge lamp (2), comprising an ignition sub-circuit (20) which is coupled via a transformer (14) to the circuit, wherein the ignition sub-circuit comprises: -at least an ignition capacitor (22); -a switching element (30) for discharging the capacitor at a desired moment in time having a control electrode; wherein the control electrode of the switching element is connected to the commutator (6, 7, 10, 16, 18) of the lamp circuit via a control sub-circuit (32, 34, 36, 38) which comprises substantially passive elements.

Abstract: The invention relates to a device for operating a high-pressure discharge lamp, comprising: a switched-mode power supply circuit for supplying power to the high-pressure discharge lamp from a supply voltage, the power supply circuit comprising at least one power switching element, and control means for controlling the at least one power switching element in its switched-on and switched-off states for controlling the power or current supplied to the high-pressure discharge lamp. According to the invention the control means are adapted to control the power consumed by the lamp during its steady phase or the current consumed by the lamp during its run-up phase by controlling the on-time (Ton) of the switched-on state of the at least one power switching element.