Abstract: Disclosed is an auxiliary battery circuit for an LED driver for driving at least one LED group. The LED driver is adapted to be powered by a main energy source. The auxiliary battery circuit comprises: a battery, a conversion circuit adapted to be connected to the LED driver and to the battery. The conversion circuit has: a first mode wherein the battery is adapted to receive energy from the LED driver, and a second mode wherein the battery is adapted to provide energy to the LED driver. A control unit of the auxiliary battery circuit is adapted to detect when the main energy source is in a failure mode, and control the conversion circuit. The control unit is adapted to arrange the conversion circuit in the second mode when the main energy source is in the failure mode.

Abstract: An LED driver is described, the LED driver comprising: a back end module BE comprising a switch mode power converter SMPS configured to operate in a self-oscillating current control mode, the back end module BE further comprising: an input terminal configured to receive a DC bus voltage; an output terminal configured to output a supply current for powering an LED fixture; a control unit configured to control the back end module to operate the SMPS in a voltage control mode by: determining a switching frequency of the SMPS when operating in the self-oscillating current control mode; determining a minimal switching frequency of the SMPS and receiving an input signal representative of the supply current for powering the LED fixture; wherein the control unit is further configured to control the switch of the SMPS in the voltage control mode by: operating the switch of the SMPS at a substantially constant frequency based on the determined minimal switching frequency and modulating a duty cycle of the switc

Abstract: A power converter powers an LED fixture from a power supply, and comprises a primary circuit a primary winding; and a switch in series connection with the primary winding to in a conductive state of the switch connect the primary winding to the power supply; a secondary circuit comprising a secondary winding that is magnetically coupled with the primary winding for providing power to the LED fixture in response to a switching of the switch; the power converter further comprising: the power converter further comprising: a sensing circuit configured to generate a signal representative of the output voltage of the secondary winding, an edge of the signal representing an edge of the output voltage of the secondary winding in response to the switching of the switch; and a detecting circuit configured to derive timing data from the edges of the signal, to estimate a load of the power converter from at least one output parameter of the power converter, and to determine a momentary value of a voltage of the

Abstract: An LED driver comprises a current source and a power supply configured to provide a power supply output voltage to the current source. The LED driver further comprises a controller configured to measure a voltage drop over the current source and to generate a feedback signal in response to the measured voltage drop. The power supply comprises a power supply regulator configured to regulate the power supply output voltage of the power supply between a minimum power supply output voltage and a maximum power supply output voltage, the power supply regulator comprising a power supply regulator input. The feedback signal is provided to the power supply regulator input, in a range from a first feedback signal value representing a minimum power supply output voltage to a second feedback signal value representing a maximum power supply output voltage.

Abstract: An LED driver is described, the LED driver comprising: a back end module BE comprising a switch mode power converter SMPS configured to operate in a self-oscillating current control mode, the back end module BE further comprising: an input terminal configured to receive a DC bus voltage; an output terminal configured to output a supply current for powering an LED fixture; a control unit configured to control the back end module to operate the SMPS in a voltage control mode by: determining a switching frequency of the SMPS when operating in the self-oscillating current control mode; determining a minimal switching frequency of the SMPS and receiving an input signal representative of the supply current for powering the LED fixture; wherein the control unit is further configured to control the switch of the SMPS in the voltage control mode by: operating the switch of the SMPS at a substantially constant frequency based on the determined minimal switching frequency and modulating a duty cycle of the switc

Abstract: A power converter powers an LED fixture from a power supply, and comprises a primary circuit a primary winding; and a switch in series connection with the primary winding to in a conductive state of the switch connect the primary winding to the power supply; a secondary circuit comprising a secondary winding that is magnetically coupled with the primary winding for providing power to the LED fixture in response to a switching of the switch; the power converter further comprising: the power converter further comprising: a sensing circuit configured to generate a signal representative of the output voltage of the secondary winding, an edge of the signal representing an edge of the output voltage of the secondary winding in response to the switching of the switch; and a detecting circuit configured to derive timing data from the edges of the signal, to estimate a load of the power converter from at least one output parameter of the power converter, and to determine a momentary value of a voltage of the

Abstract: An LED driver comprises a current source and a power supply configured to provide a power supply output voltage to the current source. The LED driver further comprises a controller configured to measure a voltage drop over the current source and to generate a feedback signal in response to the measured voltage drop. The power supply comprises a power supply regulator configured to regulate the power supply output voltage of the power supply between a minimum power supply output voltage and a maximum power supply output voltage, the power supply regulator comprising a power supply regulator input. The feedback signal is provided to the power supply regulator input, in a range from a first feedback signal value representing a minimum power supply output voltage to a second feedback signal value representing a maximum power supply output voltage.

Abstract: Some embodiments are directed to a three-phase power converter for converting power between a power grid network and a battery that includes a three-phase grid transformer, a three-phase switching converter for coupling to a positive terminal of the battery, a first, second and third series inductors coupled between the three-phase grid transformer and the three-phase switching converter, a control circuit configured for controlling a first, second and third phase differences between first, second and third time-periodical power grid voltage signals provided by the grid transformer and first, second and third converter time-periodical voltage signals provided to the switching converter such that the first, second and third time-periodical power grid voltage signals and first, second and third converter time-periodical currents are in phase. The three-phase grid transformer provides electrical isolation between the power grid network and the battery.

Abstract: Some embodiments are directed to a three-phase power converter for converting power between a power grid network and a battery that includes a three-phase grid transformer, a three-phase switching converter for coupling to a positive terminal of the battery, a first, second and third series inductors coupled between the three-phase grid transformer and the three-phase switching converter, a control circuit configured for controlling a first, second and third phase differences between first, second and third time-periodical power grid voltage signals provided by the grid transformer and first, second and third converter time-periodical voltage signals provided to the switching converter such that the first, second and third time-periodical power grid voltage signals and first, second and third converter time-periodical currents are in phase. The three-phase grid transformer provides electrical isolation between the power grid network and the battery.

Abstract: The present invention relates to a multiple output flyback converter having a switch regulated output circuit (5). To avoid a second communication interval, due an output voltage in this secondary controlled output that is lower what is implied by its number of winding turns, the inductance of this circuit is increased. This can preferably be done by increasing the leakage inductance of the winding (6) in the regulated circuit.

Abstract: The present invention relates to a class-D amplifier having a pre-processing unit (13). The pre-processing unit is arranged to limit the signal inputted to the amplifier when the amplifier switching frequency drops in order to avoid disturbances occurring when the switching frequency cuts through the amplifier output filter. To this end the amplifier has a comparator (14) that is arranged to compare the signal from the pre-processing unit with the amplifier supply voltage, and means for limiting the gain or increasing the attenuation of the pre-processing unit when the pre-processed signal amplitude exceeds a certain fraction of the supply voltage.

Abstract: A method for measuring a common mode current (Icm) in an outer conductor of a shielded electrical connector comprising also at least one inner conductor which includes the steps of interconnecting the one inner conductor and the outer conductor at a junction point to a power source and supplying a current (Icm) to the junction point draining substantially all common mode current (Icm) from the outer conductor at the opposite side of the connector by means of a low impedance drain; and sensing the drained common mode current (Icm) with a current sensing device.

Abstract: A method for measuring a common mode current (Icm) in an outer conductor of a device comprising also at least one inner conductor which includes the steps of interconnecting the one inner conductor and the outer conductor at a junction point to a power source and supplying a current (Icm) to the junction point draining substantially all common mode current (Icm) from the outer conductor at the opposite side of the device by means of a low impedance drain; and sensing the drained common mode current (Icm) with a current sensor.