Abstract: The present invention relates to multi-phase parallel-interleaved converter circuits with each phase having two or more transformers and two or more rectifiers electrically coupled to the two or more transformers, and layouts of the transformers and the rectifiers of the multi-phase parallel-interleaved converter circuits. In the layouts, the multiple transformers and the multiple rectifiers of the multi-phase converters are interleavingly arranged to be symmetrical to common output polarized capacitor(s) so as to ensure the rectifier outputs of each phase relative to the common output polarized capacitors is symmetrical, thereby reducing the output ripples of the current of the output capacitors.

Abstract: Disclosed are a hybrid heat sink and a hybrid heat sink assembly for a power module. The hybrid heat sink comprises a base provided with at least one power module on one side thereof, a first heat dissipation unit being a first heat dissipation fin group which is composed of a plurality of heat dissipation fins intervally arranged and is located on the other side of the base, and a second heat dissipation unit comprising a plurality of heat pipes and a second heat dissipation fin group. Each of the heat pipes comprises an evaporating section provided in the base and close to the power module, a condensing section, and an adiabatic section located between the evaporating section and the condensing section and comprises an extension portion and a folding portion, the second heat dissipation fin group is provided on the condensing sections.

Abstract: Provided is a lamp ballast having a filament heating apparatus for gas discharge lamp, including a PFC converter for receiving an AC input voltage and converting the AC input voltage into a DC bus voltage; an inverter connected to an output end of the PFC converter for converting the DC bus voltage into an AC output voltage for driving gas discharge lamps; and a filament heating apparatus connected to the output end of the PFC converter. The filament heating apparatus includes an auxiliary heating circuit for converting the DC bus voltage into a heating power for pre-heating the filaments of the gas discharge lamps; and a control circuit connected to the inverter and the auxiliary heating circuit for generating an auxiliary voltage according to the heating power to activate the PFC converter.

Abstract: A method of controlling an ignition circuit to output an excitation voltage is disclosed. The ignition circuit is used to excite a discharge lamp and includes a transformer and a switch element which is connected to a primary winding of the transformer. The method of controlling the ignition circuit comprises steps of: (a) receiving a control signal which is set in accordance with a waveform characteristic of a predetermined excitation voltage to control an impedance of the switch element; (b) controlling a primary current in the primary winding or a primary voltage across the primary winding of the transformer by controlling the impedance of the switch element; and (c) generating the excitation voltage by the secondary winding of the transformer in accordance with the primary current or the primary voltage so as to excite the discharge lamp.

Abstract: A high intensity discharge lamp (HID) control circuit and method are provided in the present invention. The circuit includes a first winding and a second winding, both of which are coupled with a series-connected inductor of an HID lamp circuit; a current zero point detector for detecting an inductor current zero crossing signal in the HID lamp circuit; an inductor current signal generator for generating an inductor current signal in the circuit to indicate a current value of the HID lamp; a modulator having input terminals connected to the current zero point detector and the inductor current signal generator, respectively, and an output terminal connected to a driving circuit for the HID lamp; and the driving circuit for driving switches in the HID lamp control circuit.

Abstract: A capacitor discharging circuit and a power converter having the capacitor discharging circuit are disclosed. The capacitor discharging circuit comprises a conversion module connected with the two terminals of the capacitor, an AC power-off detecting unit used to detect on-off state of AC power, and a control unit. The conversion module comprises an energy consumption unit. When AC power is disconnected, the AC power-off signal generated by the AC power-off detecting unit intervenes the control unit to control the energy consumption unit to consume the energy stored in the capacitor.

Abstract: Disclosed is an end-of-life detector for gas discharge lamp and the ballast incorporating the same. The end-of-life detector includes a lamp state signal detecting circuit for detecting the lamp state signal of at least one first gas discharge lamp and generating a positive voltage signal and a negative voltage signal accordingly; a comparing circuit for comparing the positive voltage signal with a positive selecting voltage and comparing the negative voltage signal with a negative selecting voltage, and in response thereto generating a positive control signal and a negative control signal; and a positive/negative duty time interval detecting circuit for generating a lamp life state signal which is generated by a difference between a positive duty time interval and a negative duty time interval. The lamp life state signal is varied along with the difference between the positive duty time interval and the negative duty time interval.

Abstract: The present application discloses an open circuit protecting circuit, an open circuit protecting method and an illuminating apparatus. The open circuit protecting circuit is configured in an apparatus with a LED load being supplied with power by a current source, and comprises: a switch circuit, a timer circuit and a detecting circuit. When the LED load malfunctions, the open circuit protecting circuit carries out the following operations: the detecting circuit sends an enabling signal to the timer circuit, the timer circuit sends a driving signal with a set time to the switch circuit and the switch circuit is in the on-state during the set time, so as to make the LED load be short circuited to protect the circuit from being damaged. The open circuit protecting circuit can also resume to normal work automatically after the open circuited malfunction is cleared, and thus a hot-plugging function can be realized.

Abstract: The present invention provides an illumination device, an illumination system, and a lamp. The illumination system includes the illumination device and a light modulation module. The illumination device includes a light emitting diode (LED) array, an alternating current (AC) current source, and an output power control module. The AC current source is electrically coupled to the LED array. The output power control module is electrically coupled to the LED array and the AC current source. The LED array, the AC current source, and the output power control module together form a closed-loop control loop. The light modulation module is electrically coupled to the closed-loop control loop for modulating illumination brightness of the LED.

Abstract: The present application discloses a light emitting diode lighting device and a light emitting diode lamp, the light emitting diode lighting device includes: a fluorescent lamp ballast outputting an alternating current; and at least one first light emitting diode lamp coupled with the fluorescent lamp ballast, and comprising a rectifying and filtering circuit and at least one light emitting diode string coupled with the rectifying and filtering circuit. The present application directly replaces a conventional fluorescent lamp tube with a properly designed LED lamp without any other modifications when reinstallation a conventional fluorescent lamp lighting device into a light emitting diode lighting device, which may reduce the cost of reinstallation, and greatly facilitate the user.

Abstract: An electronic ballast for driving a light-emitting device, includes a square wave generator having a plurality of switch elements for converting a DC input voltage into a square-wave AC voltage. A transformer has a driving winding and a plurality of inductive windings mutually connected with each other, in which at least a portion of the inductive windings are respectively connected to a control terminal of the switch element. A resonant circuit connects the driving winding and a light-emitting device and converts the square-wave voltage into an AC output voltage to drive the light-emitting device. An auxiliary control unit connected to the transformer regulates a voltage waveform of the driving winding or a voltage waveform of the inductive winding according to a control signal, thereby changing the voltage waveform of the inductive winding connected to the switch element to adjust the switching frequencies of the switch elements.

Abstract: The configurations of a parallel-connected resonant converter circuit and a controlling method thereof are provided in the present invention. The proposed circuit includes a plurality of resonant converters, each of which has two input terminals and two output terminals, wherein all the two input terminals of the plurality of resonant converters are electrically series-connected, and all the two output terminals of the plurality of resonant converters are electrically parallel-connected.

Abstract: A method and circuit for improving the crest factor of the gas discharge lamp. The method includes: the signal of the gas discharge lamp can be sampled to get a status signal; whether the present stage of the gas discharge lamp is at warm up stage or constant power stage can be judged based on the result of comparison between the status signal and a preset value; preset parameters can be selected based on the stage of the gas discharge lamp, the first parameter can be selected when the gas discharge lamp is at a warm up stage, and the second parameter can be selected when the gas discharge lamp is at a constant power stage; a control signal can be outputted during the lamp current commutation based on the selected first or second parameter to improve the crest factor of the gas discharge lamp.

Abstract: The configurations of a resonant converter system and a controlling method thereof are provided. The proposed resonant converter system includes a resonant converter and a hybrid control apparatus coupled to the resonant converter for generating a driving signal to adjust a phase angle and a frequency of the resonant converter such that the resonant converter would reach a relatively lower voltage gain and have a relatively lower loss during an abnormal operation.

Abstract: A ballast which controls the open-circuit voltage of the ballast. The ballast includes a power factor corrector (PFC) for receiving an AC input voltage and converting the AC input voltage into a power factor corrected DC voltage; a DC/DC converter connected to the PFC and having a switch placed at a low-voltage side of the DC/DC converter for converting the DC voltage of the PFC into a DC output voltage according to the switching operation of the switch; a controller connected to a control terminal of the switch of the DC/DC converter for sending a switching control signal to control the switch; and an open-circuit voltage controller for detecting a voltage associated with the open-circuit voltage of the ballast and regulating the duty ratio or pulse density or switching frequency of the switching control signal in response to the results of the detection, thereby controlling the open-circuit voltage.

Abstract: The electronic ballast includes: a square wave generator that includes a plurality of switching elements to convert a DC input voltage to an AC square wave output voltage; a transformer that includes a driving winding, a plurality of control windings, at least one inductive winding and at least one control driving circuit. The control windings controls the plurality of switching elements to turn on alternately; a resonant circuit that constitutes a resonant loop together with the driving winding is electrically connected with an output terminal of the square wave generator to drive the light emitting element. The control driving circuit is connected with two terminals of the inductive winding in parallel and receives a control signal to control a voltage across the inductive winding so as to control conducting time of at least one of the switching elements.

Abstract: The configurations of a three-phase buck-boost power factor correction (PFC) circuit and a controlling method thereof are provided in the present invention. The proposed circuit includes a first single-phase buck-boost PFC circuit receiving a first phase voltage and having a first and a second output terminals and a neutral-point for outputting a first and a second output voltages, a second single-phase buck-boost PFC circuit receiving a second phase voltage and coupled to the first and the second output terminals and the neutral-point, a third single-phase buck-boost PFC circuit receiving a third phase voltage and coupled to the first and the second output terminals and the neutral-point, a first and a second output capacitors coupled to the first and the second output terminals respectively, and to the neutral-point also and a neutral line coupled to the neutral-point.

Abstract: The present application discloses a laminated busbar arrangement for use in a three-level power converter and a power converter. The laminated busbar arrangement comprises a first layer of busbar comprising a neutral-point sub busbar congfigured to make electrical connections between respective components in the three-level power converter and a neutral-point potential; a second layer of busbar comprising a plurality of sub busbars congfigured to make electrical connections between the respective components in the three-level power converter and a positive direct current (DC) input, a negative DC input and an alternating current (AC) input/output in the three-level power converter, and between respective semiconductor switching components. The present application may effectively reduce stray inductance.

Abstract: The configurations of a single-phase dual buck-boost/buck power factor correction (PFC) circuit and a controlling method thereof are provided in the present invention. The proposed circuit includes a single-phase three-level buck-boost PFC circuit receiving an input voltage and having a first output terminal, a neutral-point and a second output terminal for outputting a first and a second output voltages, a single-phase three-level buck PFC circuit receiving the input voltage and coupled to the first output terminal, the neutral-point and the second output terminal, a first output capacitor coupled to the first output terminal and the neutral-point, a second output capacitor coupled to the neutral-point and the second output terminal, and a neutral line coupled to the neutral-point.

Abstract: The invention provides a current balancing circuit, which includes a plurality of light-emitting diode assemblies; an AC power generator for providing currents required by the light-emitting diode assemblies; and a plurality of current-equaling elements connected to the AC power generator, each of which is connected to a common mode connecting two light-emitting diode assemblies for balancing currents of the light-emitting diode assemblies.