Abstract: Resonant DC-DC converters use a switching network to step a single DC voltage up to a working DC level using a resonant tank. However, high voltage DC power supply systems, for example, those used to power X-ray sources, are increasingly being integrated into smaller form factors, and it is becoming attractive to be able to make use of multiple DC-DC power supplies to power such X-ray sources. The present invention provides a topology for a resonant DC-DC converter, a DC electrical supply system, and method of operating a DC-DC resonant converter. The proposed topology uses a switching network to connect multiple DC power supplies to the resonant tank, to enable a more flexible provision of input power.

Abstract: The present invention relates to a converter circuit (1) for reducing a nominal capacitor voltage, the converter circuit (1) comprising: an input node (TI1), which is configured to receive an input voltage (VG); an output node (TO1; TO2), which is configured to supply an output voltage (VO) to a load (RL1; RL2); and a capacitor (C1; C2), which is coupled to the load so that the input voltage is divided between the capacitor (C1; C2) and the load (RL1; RL2) and which is configured to be charged up to a voltage corresponding to a differential voltage between the input voltage (VG) and the output voltage (VO).

Abstract: A high voltage transformer (50) includes a magnetic core (5); a low voltage winding (10); a high voltage winding (20); at least one inner sleeve (30); and a coil bobbin (24) for carrying the high voltage winding (20). The coil bobbin (24) is configured to be arranged inside the at least one inner sleeve (30) and configured to be attached to the at least one inner sleeve (30) at an outer perimeter of the at least one inner sleeve (30). The coil bobbin (24) includes at least one field-control electrode (22), which is adapted to shape an electric field generated by the high voltage winding (20).

Abstract: The present invention relates to a converter circuit (1) for reducing a nominal capacitor voltage, the converter circuit (1) comprising: an input node (TI1), which is configured to receive an input voltage (VG); an output node (TO1; TO2), which is configured to supply an output voltage (VO) to a load (RL1; RL2); and a capacitor (C1; C2), which is coupled to the load so that the input voltage is divided between the capacitor (C1; C2) and the load (RL1; RL2) and which is configured to be charged up to a voltage corresponding to a differential voltage between the input voltage (VG) and the output voltage (VO).

Abstract: The present invention relates to a control device (1) for a multiple-input multiple-output converter (100) comprising: a first transformation block controller (21), which is configured to split outputs of the multiple-input multiple-output converter (100) into independent sets of outputs representing at least two independent virtual converters (100-1, 100-2, . . . , 100-n); a first converter controller (10), which is configured to control a first virtual converter (100-1) of the at least two independent virtual converters (100-1, 100-2, . . . , 100-n) by providing a first controlling signal based on the independent sets of outputs; a second converter controller (30), which is configured to control a second virtual converter (100-2) of the at least two independent virtual converters (100-1, 100-2, . . .

Abstract: The present invention relates to a bobbin assembly (1000-3) comprising: a plurality of winding slots (1000-4), each of which comprises a winding (10) with one turn per layer; and a plurality of isolation slots (1000-5), each of which comprises one single loop of the winding (10), and each of the isolation slots (1000-5) is adjacent to at least one winding slot (1000-4) of the plurality of winding slots (1000-4), and each of the winding slots (1000-4) is adjacent to at least one isolation slot (1000-5) of the plurality of isolation slots (1000-5).

Abstract: The invention relates to a high voltage transformer (50) comprising: a magnetic core (5); a low voltage winding (10); a high voltage winding (20); at least one inner sleeve (30); and a coil bobbin (24) for carrying the high voltage winding (20), wherein the coil bobbin (24) is configured to be arranged inside the at least one inner sleeve (30) and configured to be attached to the at least one inner sleeve (30) at an outer perimeter of the at least one inner sleeve (30); and wherein the coil bobbin (24) comprises at least one field-control electrode (22), which is adapted to shape an electric field generated by the high voltage winding (20).

Abstract: A lighting device for generating colored and white light. According to the invention the lighting device comprises at least one light source (1, 4) emitting blue or ultraviolet light and a color conversion unit (2, 5) for converting said blue or ultraviolet light into visible light comprising at least two sections (2a, 2b, 2c, 6a, 6b, 6c, 6d), at least one section (2c, 6d) of which being a transparent or translucent color converting section, said color conversion unit (2, 5) being arranged for alternately illuminating said at least two sections (2a, 2b, 2c, 6a, 6b, 6c, 6d) with said blue or ultraviolet light, said at least one color converting section containing luminescent material, wherein said luminescent material is a luminescent organic dye in a polymer matrix or a crystalline inorganic luminescent material.

Abstract: Current switching point determination devices use two comparators with fixed threshold values. A power inverter control device for switching point determination is provided which includes a filter circuit and a subsequent single comparator. By this arrangement, the time event is independent of the amplitude and for sufficiently small frequencies also of the frequency.

Abstract: A controller is described, which is particularly suited for a power supply with switching elements (S1, S2), such as a switching mode power supply. The controller comprises a logical unit (18) which calculates a binary state value Zk by a first logical operation from a binary input value I and a prior binary state value Zk?1. The logical unit further calculates a binary output value Y by a second logical operation from the binary input value I and the binary state value Zk. In this way, fast and efficient fully digital control may be realized especially for a switching mode power supply, where the binary input value I is a comparator value and the binary output value Y is used to drive the switch elements (S1, S2). An adaptation unit (20), which may be a signal processor, determines the logical operations and delivers them to the logical unit (18) during operation of the controller unit (16).

Abstract: An apparatus and method for determining an output voltage or output current in an SMPS circuit 10 are described. The SMPS circuit comprises a switching element 18 which in operation is switched according to consecutive switching cycles. An electrical value IL within the SMPS circuit 10 is compared to a reference value Iref. The electrical value IL varies within the switching cycle such that is equal to the reference value at least once during each cycle. The comparator signal comp is evaluated to determine timing information t of an instant of change in the signal. The timing information t is used for determining the output voltage Vout,Av or output current Iout,Av.

Abstract: The invention relates to a resonant power LED control circuit for the independent, simultaneous brightness and color or color temperature control of two LEDs (41, 42) or two groups of LEDs, comprising a single resonant converter which is essentially formed from a half or full bridge DC/AC converter (2) with a control unit (21), a resonant capacitor, and a transformer (3).

Abstract: A lighting device for generating colored and white light. According to the invention the lighting device comprises at least one light source (1, 4) emitting blue or ultraviolet light and a color conversion unit (2, 5) for converting said blue or ultraviolet light into visible light comprising at least two sections (2a, 2b, 2c, 6a, 6b, 6c, 6d), at least one section (2c, 6d) of which being a transparent or translucent color converting section, said color conversion unit (2, 5) being arranged for alternately illuminating said at least two sections (2a, 2b, 2c, 6a, 6b, 6c, 6d) with said blue or ultraviolet light, said at least one color converting section containing luminescent material, wherein said luminescent material is a luminescent organic dye in a polymer matrix or a crystalline inorganic luminescent material.

Abstract: Current switching point determination devices use two comparators with fixed threshold values. According to an exemplary embodiment of the present invention, a power inverter control device for switching point determination is provided which comprises a filter circuit and a subsequent single comparator. By this arrangement, the time event is independent of the amplitude and for sufficiently small frequencies also of the frequency.

Abstract: The invention relates to a DC/DC converter for use in a decentralized power generation system. If a DC/DC converter is physically separated from a power receiving component and connected to such a power receiving component via a DC bus, a short-circuit on the DC bus may endanger the system and service personnel. In order to minimize such a risk, it is proposed that the DC/DC converter comprises a converting component for DC/DC converting a direct current supplied by a power generating unit and for supplying a resulting converted direct current to a DC bus, and that the DC/DC converter comprises in addition a control component arranged to monitor a voltage at the outputs of the DC/DC converter and to cause the converting component to enter a short-circuit protection mode if the monitored voltage lies below a predetermined voltage threshold. The invention relates equally to a corresponding system and to a corresponding method.

Abstract: A method of determining a zero point of a current sensor in a circuit arrangement for operating a gas discharge lamp includes switching off the current through the sensor for a short period during a first half wave and determining a first test value. Then the current through the sensor is switched off for a short period during a second half wave having a different polarity and a second test value is determined. The average value of the two test values is formed and the zero point is determined using the average value. It is prevented thereby that the zero point drifts during lamp operation, and that amplitudes of the positive and negative half waves of the lamp current are formed differently.

Abstract: A circuit and a method for operation of a gas discharge lamp includes a switching transformer having a switch, a converter, inductor and a controller in a control loop for measuring a lamp voltage and setting a desired power. The switching transformer further includes a second control loop used for adjusting the switching transformer to individual lamp conditions.

Abstract: A projection system for image reproduction includes at least one lamp and sensor for generating a sensor signal for monitoring changes in the luminous flux generated by the lamp and for compensating these changes through a suitable control of the image reproduction. The projection system further includes a device for eliminating substantially periodic interference components from the sensor signal generated by the sensor. These interference components may be generated by an optical component such as a color modulator of the projection system. The projection system provides substantially interference-free compensation of fluctuations in the luminous flux generated by the lamp, for example, owing to an unstable arc discharge. Further, the positioning of the sensor in the projection system may not be critical.

Abstract: The invention relates to a method for operating a discharge lamp 11 including two electrodes 12,13. The method comprises applying to the electrodes an alternating current ILamp. In order to improve the performance of the lamp and to increase the life time of the lamp, it is proposed that the alternating current has a direct current component DC for compensating a temperature difference between the two electrodes. The direct current component is selected more specifically such that a first electrode, which is expected to have a lower temperature than the second electrode, functions as anode for the direct current component, while the second electrode functions as cathode for the direct current component. The invention relates equally to an electronic circuit and to a software program for operating a discharge lamp correspondingly, as well as to a lighting system comprising a discharge lamp and means for operating this discharge lamp correspondingly.

Abstract: A circuit includes a converter for converting an a.c. voltage into a d.c. voltage. The converter has a diode half-bridge, a switch half-bridge, and two d.c. rails. Further, the converter has a second converter for converting the a.c. voltage into a second d.c. voltage.